IMRA AMERICA, INC. Patent applications |
Patent application number | Title | Published |
20160099541 | OPTICAL PULSE SOURCE WITH INCREASED PEAK POWER - In at least one embodiment time separated pulse pairs are generated, followed by amplification to increase the available peak and/or average power. The pulses are characterized by a time separation that exceeds the input pulse width and with distinct polarization states. The time and polarization discrimination allows easy extraction of the pulses after amplification. In some embodiments polarization maintaining (PM) fibers and/or amplifiers are utilized which provides a compact arrangement. At least one implementation provides for seeding of a solid state amplifier or large core fiber amplifier with time delayed, polarization split pulses, with capability for recombining the time separated pulses at an amplifier output. In various implementations suitable combinations of bulk optics and fibers may be utilized. In some implementations wavelength converted pulse trains are generated. A method and system of the present invention can be used in time domain applications utilizing multiple beam paths, for example spectroscopy. | 04-07-2016 |
20160099537 | COMPACT, COHERENT, HIGH BRIGHTNESS LIGHT SOURCES FOR THE MID AND FAR IR - Compact high brightness light sources for the mid and far IR spectral region, and exemplary applications are disclosed based on passively mode locked Tm fiber comb lasers. In at least one embodiment the coherence of the comb sources is increased in a system utilizing an amplified single-frequency laser to pump the Tm fiber comb laser. The optical bandwidth generated by the passively mode locked Tm fiber comb laser is further decreased by using simultaneous 2 | 04-07-2016 |
20160097963 | FREQUENCY COMB SOURCE WITH LARGE COMB SPACING - A frequency comb laser providing large comb spacing is disclosed. At least one embodiment includes a mode locked waveguide laser system. The mode locked waveguide laser includes a laser cavity having a waveguide, and a dispersion control unit (DCU) in the cavity. The DCU imparts an angular dispersion, group-velocity dispersion (GVD) and a spatial chirp to a beam propagating in the cavity. The DCU is capable of producing net GVD in a range from a positive value to a negative value. In some embodiments a tunable fiber frequency comb system configured as an optical frequency synthesizer is provided. In at least one embodiment a low phase noise micro-wave source may be implemented with a fiber comb laser having a comb spacing greater than about 1 GHz. The laser system is suitable for mass-producible fiber comb sources with large comb spacing and low noise. Applications include high-resolution spectroscopy. | 04-07-2016 |
20160094010 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 03-31-2016 |
20160094008 | OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δf | 03-31-2016 |
20160067822 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER - Methods, devices, and systems for ultrashort pulse laser processing of optically transparent materials are disclosed, with example applications in scribing, marking, welding, and joining. For example, ultrashort laser pulses create scribe features with one pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with correctly aligned illumination. Reflective marks may also be formed with control of laser parameters. A transparent material other than glass may be utilized. A method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating. In some embodiments of transparent material processing, a multifocus beam generator simultaneously forms multiple beam waists spaced depthwise relative to the transparent material, thereby increasing processing speed. | 03-10-2016 |
20160006208 | MODE-LOCKED MULTI-MODE FIBER LASER PULSE SOURCE - A laser utilizes a cavity design which allows the stable generation of high peak power pulses from mode-locked multi-mode fiber lasers, greatly extending the peak power limits of conventional mode-locked single-mode fiber lasers. Mode-locking may be induced by insertion of a saturable absorber into the cavity and by inserting one or more mode-filters to ensure the oscillation of the fundamental mode in the multi-mode fiber. The probability of damage of the absorber may be minimized by the insertion of an additional semiconductor optical power limiter into the cavity. | 01-07-2016 |
20150380892 | OPTICAL SIGNAL PROCESSING WITH MODELOCKED LASERS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. In some embodiments an effective CDSL is constructed with only one laser. At least one embodiment includes a coherent scanning laser system (CSL) for generating pulse pairs with a time varying time delay. A CDSL, effective CDSL, or CSL may be arranged in an imaging system for one or more of optical imaging, microscopy, micro-spectroscopy and/or THz imaging. | 12-31-2015 |
20150372445 | FEMTOSECOND LASER PROCESSING SYSTEM WITH PROCESS PARAMETERS CONTROLS AND FEEDBACK - A femtosecond laser based laser processing system having a femtosecond laser, frequency conversion optics, beam manipulation optics, target motion control, processing chamber, diagnostic systems and system control modules. The femtosecond laser based laser processing system allows for the utilization of the unique heat control in micromachining, and the system has greater output beam stability, continuously variable repetition rate and unique temporal beam shaping capabilities. | 12-24-2015 |
20150311666 | COMPACT ULTRA-SHORT PULSE SOURCE AMPLIFIERS - The present invention relates to compact, low noise, ultra-short pulse sources based on fiber amplifiers, and various applications thereof. At least one implementation includes an optical amplification system having a fiber laser seed source producing seed pulses at a repetition rate corresponding to the fiber laser cavity round trip time. A nonlinear pulse transformer, comprising a fiber length greater than about 10 m, receives a seed pulse at its input and produces a spectrally broadened output pulse at its output, the output pulse having a spectral bandwidth which is more than 1.5 times a spectral bandwidth of a seed pulse. A fiber power amplifier receives and amplifies spectrally broadened output pulses. A pulse compressor is configured to temporally compress spectrally broadened pulses amplified by said power amplifier. Applications include micro-machining, ophthalmology, molecular desorption or ionization, mass-spectroscopy, and/or laser-based, biological tissue processing. | 10-29-2015 |
20150280227 | PREDOPING METHOD FOR AN ELECTRODE ACTIVE MATERIAL IN AN ENERGY STORAGE DEVICE, AND ENERGY STORAGE DEVICES - A predoping method for a negative electrode active material of an energy storage device, comprising at least one predoping material that can provide an ion that is different from a primary ionic charge carrier for a charging and discharging process of the energy storage device, called non-primary predoping material. The predoping material may be first included in a predoping electrode and later discharged to the negative electrode active material. The predoping material may be first mixed with the negative electrode active material in an electrode fabrication process, and later made to directly contact the negative electrode active material by adding an electrolyte and removing the protective shells of the predoping material. An ion exchanging method is used to exchange a first ion coming from the predoping material for a second ion in an electrode stack. | 10-01-2015 |
20150255942 | ALL-FIBER CHIRPED PULSE AMPLIFICATION SYSTEMS - By compensating polarization mode-dispersion as well chromatic dispersion in photonic crystal fiber pulse compressors, high pulse energies can be obtained from all-fiber chirped pulse amplification systems. By inducing third-order dispersion in fiber amplifiers via self-phase modulation, the third-order chromatic dispersion from bulk grating pulse compressors can be compensated and the pulse quality of hybrid fiber/bulk chirped pulse amplification systems can be improved. Finally, by amplifying positively chirped pulses in negative dispersion fiber amplifiers, a low noise wavelength tunable seed source via anti-Stokes frequency shifting can be obtained. | 09-10-2015 |
20150249317 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 09-03-2015 |
20150207289 | HIGH POWER PARALLEL FIBER ARRAYS - High power parallel fiber arrays for the amplification of high peak power pulses are described. Fiber arrays based on individual fiber amplifiers as well as fiber arrays based on multi-core fibers can be implemented. The optical phase between the individual fiber amplifier elements of the fiber array is measured and controlled using a variety of phase detection and compensation techniques. High power fiber array amplifiers can be used for EUV and X-ray generation as well as pumping of parametric amplifiers. | 07-23-2015 |
20150187558 | PULSE-BURST ASSISTED ELECTROSPRAY IONIZATION MASS SPECTROMETER - The present invention relates to a mass spectrometer system, which combines laser desorption with pulse bursts comprising a train of ultrashort pulses and electrospray ionization. The pulse separation between individual pulses within the pulse burst is selected such that transient phenomena on an irradiated sample do not fully relax between individual pulses. Pulses with pulse widths ranging from fs to sub ns are conveniently implemented. The pulse widths can be selected to allow for multi-photon excitation of a sample while at the same time minimizing heat accumulation in a sample. Low cost laser systems such as fiber lasers can be configured to generate appropriate pulse bursts. The technique is suitable for mass spectrometry imaging with high spatial resolution. The laser system can serve as an electronic clock to which the whole mass spectrometry system or mass spectrometry imaging system is synchronized. | 07-02-2015 |
20150180194 | CONTROLLABLE MULTI-WAVELENGTH LASER SOURCE - In at least one embodiment a laser system includes a fiber laser source, a polarization controller and a wavelength converter. The relative power distribution between a pump wavelength and a signal wavelength is controllable using the polarization controller. An optional phase compensator is used to control polarization state of the output laser beam. In various embodiments the relative power distribution among multiple wavelengths may be controlled over a range of at least about 100:1. | 06-25-2015 |
20150160532 | BROADBAND GENERATION OF MID IR, COHERENT CONTINUA WITH OPTICAL FIBERS - Coherent and compact supercontinuum light sources for the mid IR spectral regime are disclosed and exemplary applications thereof. The supercontinuum generation is based on the use of highly nonlinear fibers or waveguides. In at least one embodiment the coherence of the supercontinuum sources is increased using low noise mode locked short pulse sources. Compact supercontinuum light sources can be constructed with the use of passively mode locked fiber or diode lasers. Wavelength tunable sources can be constructed using appropriate optical filters or frequency conversion sections. Highly coherent supercontinuum sources further facilitate coherent detection schemes and can improve the signal/noise ratio in lock in detection schemes. | 06-11-2015 |
20150110882 | MULTIFUNCTIONAL METALLIC NANOSTRUCTURE AND METHOD FOR MANUFACTURING THE SAME - It is intended to provide a stable metallic nanostructure that causes no aggregation when surface-modified with biomolecule-reactive functional molecules. 30 to 90% of the surface of a metallic nanostructure is covered with at least one or more types of colloid-stabilizing functional molecules. The remaining portions on the surface of the metallic nanostructure are further covered with one or more types of biologically functional molecules. | 04-23-2015 |
20150085885 | HIGH POWER SHORT PULSE FIBER LASER - A pulsed laser comprises an oscillator and amplifier. An attenuator and/or pre-compressor may be disposed between the oscillator and amplifier to improve performance and possibly the quality of pulses output from the laser. Such pre-compression may be implemented with spectral filters and/or dispersive elements between the oscillator and amplifier. The pulsed laser may have a modular design comprising modular devices that may have Telcordia-graded quality and reliability. Fiber pigtails extending from the device modules can be spliced together to form laser system. In one embodiment, a laser system operating at approximately 1050 nm comprises an oscillator having a spectral bandwidth of approximately 19 nm. This oscillator signal can be manipulated to generate a pulse having a width below approximately 90 fs. A modelocked linear fiber laser cavity with enhanced pulse-width control includes concatenated sections of both polarization-maintaining and non-polarization-maintaining fibers. Apodized fiber Bragg gratings and integrated fiber polarizers are included in the cavity to assist in linearly polarizing the output of the cavity. Very short pulses with a large optical bandwidth are obtained by matching the dispersion value of the fiber Bragg grating to the inverse of the dispersion of the intra-cavity fiber. | 03-26-2015 |
20150036702 | MODE-LOCKED MULTI-MODE FIBER LASER PULSE SOURCE - A laser utilizes a cavity design which allows the stable generation of high peak power pulses from mode-locked multi-mode fiber lasers, greatly extending the peak power limits of conventional mode-locked single-mode fiber lasers. Mode-locking may be induced by insertion of a saturable absorber into the cavity and by inserting one or more mode-filters to ensure the oscillation of the fundamental mode in the multi-mode fiber. The probability of damage of the absorber may be minimized by the insertion of an additional semiconductor optical power limiter into the cavity. | 02-05-2015 |
20150030045 | NOISE DETECTION, DIAGNOSTICS, AND CONTROL OF MODELOCKED LASERS - The present invention features a laser based system configured with a noise detection unit. The system includes a mode-locked oscillator. A noise detection unit includes at least one optical detector that monitors optical pulses generated by the mode-locked oscillator and produces an electrical signal in response to the optical pulses. The noise detection unit includes a first filter to transmit signal power over a signal bandwidth which includes the mode-locked laser repetition frequency, frep. The noise detection unit may include one or more filters to transmit power over a noise bandwidth that substantially excludes repetition frequency, frep. Non-linear signal processing equipment is utilized to generate one or more signals representative of the power in the signal bandwidth relative to the power in the noise bandwidth. The system includes a controller operable to generate a signal for controlling the laser based system based on the relative power. | 01-29-2015 |
20150023628 | COMPACT COHERENT HIGH BRIGHTNESS LIGHT SOURCE FOR THE MID-IR AND FAR IR - Compact laser systems are disclosed which include ultrafast laser sources in combination with nonlinear crystals or waveguides. In some implementations fiber based mid-IR sources producing very short pulses and/or mid-IR sources based on a mode locked fiber lasers are utilized. A difference frequency generator receives outputs from the ultrafast sources, and generates an output including a difference frequency. The output power from the difference frequency generator can further be enhanced via the implementation of large core dispersion shifted fibers. Exemplary applications of the compact, high brightness mid-IR light sources include medical applications, spectroscopy, ranging, sensing and metrology. | 01-22-2015 |
20140376084 | YB: AND ND: MODE-LOCKED OSCILLATORS AND FIBER SYSTEMS INCORPORATED IN SOLID-STATE SHORT PULSE LASER SYSTEMS - The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier. | 12-25-2014 |
20140328358 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 11-06-2014 |
20140321483 | COMPACT OPTICAL FREQUENCY COMB SYSTEMS - Compact optical frequency sources are described. The comb source may include an intra-cavity optical element having a multi-material integrated structure with an electrically controllable active region. The active region may comprise a thin film. By way of example, the thin film and an insulating dielectric material disposed between two electrodes can provide for rapid loss modulation. In some embodiments the thin film may comprise graphene. In various embodiments of a frequency comb laser, rapid modulation of the CEO frequency can be implemented via electric modulation of the transmission or reflection loss of an additional optical element, which can be the saturable absorber itself. In another embodiment, the thin film can also be used as a saturable absorber in order to facilitate passive modelocking. In some implementations the optical element may be formed on a cleaved or polished end of an optical fiber. | 10-30-2014 |
20140314995 | PULSED LASER PROCESSING METHOD FOR PRODUCING SUPERHYDROPHOBIC SURFACES - A method of pulsed laser processing of solid surface for enhancing surface hydrophobicity is disclosed wherein the solid surface is covered with a transparent medium during laser processing and the laser beam incidents through the covering medium and irradiates the solid surface. Two effects are obtained simultaneously. One is the laser-induced texture formation directly under the laser irradiation. The other is the deposition of the laser-removed materials along the laser scan lines. Both effects introduce surface roughness on nanometer scales, and both enhance surface hydrophobicity, rendering superhydrophobicity on the surfaces of both the laser-irradiated solid and the covering medium. Because the beam scan line spacing can be larger than a single scan line width by multiple times, this method provides a high processing speed of square inch per minute and enables large area processing. | 10-23-2014 |
20140264031 | TRACE GAS DETECTION SYSTEM - The present invention relates to a trace gas detection system. At least one embodiment includes a frequency spectrum comprising a 1st comb and an enhancement cavity characterized by having a 2 | 09-18-2014 |
20140248531 | NEGATIVE ELECTRODE ACTIVE MATERIAL FOR ENERGY STORAGE DEVICES AND METHOD FOR MAKING THE SAME - The described embodiments provide an energy storage device that includes a positive electrode including a material that stores and releases ion, a negative electrode including Nb-doped TiO | 09-04-2014 |
20140233089 | PULSED LASER SOURCES - Modelocked fiber laser resonators may be coupled with optical amplifiers. An isolator optionally may separate the resonator from the amplifier. A reflective optical element on one end of the resonator having a relatively low reflectivity may be employed to couple light from the resonator to the amplifier. Enhanced pulse-width control may be provided with concatenated sections of both polarization-maintaining and non-polarization-maintaining fibers. Apodized fiber Bragg gratings and integrated fiber polarizers may also be included in the laser cavity to assist in linearly polarizing the output of the cavity. Very short pulses with a large optical bandwidth may be obtained by matching the dispersion value of the grating to the inverse of the dispersion of the intra-cavity fiber. Frequency comb sources may be constructed from such modelocked fiber oscillators. Low dispersion and an in-line interferometer that provides feedback may assist in controlling the frequency components output from the comb source. | 08-21-2014 |
20140219298 | OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δf | 08-07-2014 |
20140219296 | COMPACT COHERENT HIGH BRIGHTNESS LIGHT SOURCE FOR THE MID-IR AND FAR IR - Compact laser systems are disclosed which include ultrafast laser sources in combination with nonlinear crystals or waveguides. In some implementations fiber based mid-IR sources producing very short pulses and/or mid-IR sources based on a mode locked fiber lasers are utilized. A difference frequency generator receives outputs from the ultrafast sources, and generates an output including a difference frequency. The output power from the difference frequency generator can further be enhanced via the implementation of large core dispersion shifted fibers. Exemplary applications of the compact, high brightness mid-IR light sources include medical applications, spectroscopy, ranging, sensing and metrology. | 08-07-2014 |
20140202994 | COMPACT, COHERENT, HIGH BRIGHTNESS LIGHT SOURCES FOR THE MID AND FAR IR - Compact high brightness light sources for the mid and far IR spectral region, and exemplary applications are disclosed based on passively mode locked Tm fiber comb lasers. In at least one embodiment the coherence of the comb sources is increased in a system utilizing an amplified single-frequency laser to pump the Tm fiber comb laser. The optical bandwidth generated by the passively mode locked Tm fiber comb laser is further decreased by using simultaneous 2 | 07-24-2014 |
20140192403 | MULTI-MODE FIBER AMPLIFIER - A laser utilizes a cavity design which allows the stable generation of high peak power pulses from mode-locked multi-mode fiber lasers, greatly extending the peak power limits of conventional mode-locked single-mode fiber lasers. Mode-locking may be induced by insertion of a saturable absorber into the cavity and by inserting one or more mode-filters to ensure the oscillation of the fundamental mode in the multi-mode fiber. The probability of damage of the absorber may be minimized by the insertion of an additional semiconductor optical power limiter into the cavity. | 07-10-2014 |
20140185065 | ULTRASHORT LASER MICRO-TEXTURE PRINTING - Systems and methods for providing laser texturing of solid substrates are disclosed. The texturing may be used to provide grayscale images obtainable from substrates, which may include steel, aluminum, glass, and silicon. In some embodiments, images may be obtainable from the substrate by modifying the reflective, diffractive, and/or absorptive features of the substrate or the substrate surface by forming random, periodic, and/or semi-periodic micro-structure features on the substrate (or substrate surface) by an ultrafast laser pulse train. The ultrafast pulse train may be modulated in order to vary, for example, optical exposure time, pulse train intensity, laser polarization, laser wavelength, or a combination of the aforementioned. The ultrafast pulse train and the substrate may be scanned with respect to each other to provide different optical energies to different regions of the substrate (or substrate surface). In some embodiments, the image is provided by making one or more passes of the ultrafast laser pulse train relative to the substrate. | 07-03-2014 |
20140170476 | NEGATIVE ELECTRODE ACTIVE MATERIAL FOR ENERGY STORAGE DEVICES AND METHOD FOR MAKING THE SAME - The described embodiments provide an energy storage device that includes a positive electrode including an active material that can store and release ions, a negative electrode including an active material that is a lithiated nano-architectured active material including tin and at least one stress-buffer component, and a non-aqueous electrolyte including lithium. The negative electrode active material is nano-architectured before lithiation. | 06-19-2014 |
20140161998 | PULSED LASER MICRO-DEPOSITION PATTERN FORMATION - A method of forming patterns on transparent substrates using a pulsed laser is disclosed. Various embodiments include an ultrashort pulsed laser, a substrate that is transparent to the laser wavelength, and a target plate. The laser beam is guided through the transparent substrate and focused on the target surface. The target material is ablated by the laser and is deposited on the opposite substrate surface. A pattern, for example a gray scale image, is formed by scanning the laser beam relative to the target. Variations of the laser beam scan speed and scan line density control the material deposition and change the optical properties of the deposited patterns, creating a visual effect of gray scale. In some embodiments patterns may be formed on a portion of a microelectronic device during a fabrication process. In some embodiments high repetition rate picoseconds and nanosecond sources are configured to produce the patterns. | 06-12-2014 |
20140093744 | METHOD FOR DEPOSITING CRYSTALLINE TITANIA NANOPARTICLES AND FILMS - A one-step and room-temperature process for depositing nanoparticles or nanocomposite (nanoparticle-assembled) films of metal oxides such as crystalline titanium dioxide (TiO | 04-03-2014 |
20140092927 | FEMTOSECOND LASER PROCESSING SYSTEM WITH PROCESS PARAMETERS CONTROLS AND FEEDBACK - A femtosecond laser based laser processing system having a femtosecond laser, frequency conversion optics, beam manipulation optics, target motion control, processing chamber, diagnostic systems and system control modules. The femtosecond laser based laser processing system allows for the utilization of the unique heat control in micromachining, and the system has greater output beam stability, continuously variable repetition rate and unique temporal beam shaping capabilities. | 04-03-2014 |
20140044139 | SINGLE MODE PROPAGATION IN FIBERS AND RODS WITH LARGE LEAKAGE CHANNELS - Various embodiments include large cores fibers that can propagate few modes or a single mode while introducing loss to higher order modes. Some of these fibers are holey fibers that comprising cladding features such as air-holes. Additional embodiments described herein include holey rods. The rods and fibers may be used in many optical systems including optical amplification systems, lasers, short pulse generators, Q-switched lasers, etc. and may be used for example for micromachining. | 02-13-2014 |
20140036939 | MODULAR, HIGH ENERGY, WIDELY-TUNABLE ULTRAFAST FIBER SOURCE - A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Peak power handling capability of fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses. Dispersive pulse stretching in the presence of self-phase modulation and gain results in the formation of high-power parabolic pulses. To ensure a wide tunability of the whole system, Raman-shifting of the compact sources of ultrashort pulses in conjunction with frequency-conversion in nonlinear optical crystals can be implemented, or an Anti-Stokes fiber in conjunction with fiber amplifiers and Raman-shifters are used. Positive dispersion optical amplifiers are used to improve transmission characteristics. An optical communication system utilizes a Raman amplifier fiber pumped by a train of Raman-shifted, wavelength-tunable pump pulses, to thereby amplify an optical signal which counterpropagates within the Raman amplifier fiber with respect to the pump pulses. | 02-06-2014 |
20140036350 | HIGH POWER PARALLEL FIBER ARRAYS - High power parallel fiber arrays for the amplification of high peak power pulses are described. Fiber arrays based on individual fiber amplifiers as well as fiber arrays based on multi-core fibers can be implemented. The optical phase between the individual fiber amplifier elements of the fiber array is measured and controlled using a variety of phase detection and compensation techniques. High power fiber array amplifiers can be used for EUV and X-ray generation as well as pumping of parametric amplifiers. | 02-06-2014 |
20140022533 | FREQUENCY COMB SOURCE WITH LARGE COMB SPACING - A frequency comb laser providing large comb spacing is disclosed. At least one embodiment includes a mode locked waveguide laser system. The mode locked waveguide laser includes a laser cavity having a waveguide, and a dispersion control unit (DCU) in the cavity. The DCU imparts an angular dispersion, group-velocity dispersion (GVD) and a spatial chirp to a beam propagating in the cavity. The DCU is capable of producing net GVD in a range from a positive value to a negative value. In some embodiments a tunable fiber frequency comb system configured as an optical frequency synthesizer is provided. In at least one embodiment a low phase noise micro-wave source may be implemented with a fiber comb laser having a comb spacing greater than about 1 GHz. The laser system is suitable for mass-producible fiber comb sources with large comb spacing and low noise. Applications include high-resolution spectroscopy. | 01-23-2014 |
20140017416 | P-TYPE SEMICONDUCTOR ZINC OXIDE FILMS PROCESS FOR PREPARATION THEREOF, AND PULSED LASER DEPOSITION METHOD USING TRANSPARENT SUBSTRATES - A p-type semiconductor zinc oxide (ZnO) film and a process for preparing the film are disclosed. The film is co-doped with phosphorous (P) and lithium (Li). A pulsed laser deposition scheme is described for use in growing the film. Further described is a process of pulsed laser deposition using transparent substrates which includes a pulsed laser source, a substrate that is transparent at the wavelength of the pulsed laser, and a multi-target system. The optical path of the pulsed laser is arranged in such a way that the pulsed laser is incident from the back of the substrate, passes through the substrate, and then focuses on the target. By translating the substrate towards the target, this geometric arrangement enables deposition of small features utilizing the root of the ablation plume, which can exist in a one-dimensional transition stage along the target surface normal, before the angular width of the plume is broadened by three-dimensional adiabatic expansion. This can provide small deposition feature sizes, which can be similar in size to the laser focal spot, and provides a novel method for direct deposition of patterned materials. | 01-16-2014 |
20140004318 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER | 01-02-2014 |
20130329279 | METHOD AND APPARATUS FOR CONTROLLING AND PROTECTING PULSED HIGH POWER FIBER AMPLIFIER SYSTEMS - An electronic circuit for controlling a laser system consisting of a pulse source and high power fiber amplifier is disclosed. The circuit is used to control the gain of the high power fiber amplifier system so that the amplified output pulses have predetermined pulse energy as the pulse width and repetition rate of the oscillator are varied. This includes keeping the pulse energy constant when the pulse train is turned on. The circuitry is also used to control the temperature of the high power fiber amplifier pump diode such that the wavelength of the pump diode is held at the optimum absorption wavelength of the fiber amplifier as the diode current is varied. The circuitry also provides a means of protecting the high power fiber amplifier from damage due to a loss of signal from the pulse source or from a pulse-source signal of insufficient injection energy. | 12-12-2013 |
20130327987 | Production Of Fine Particles Of Functional Ceramic By Using Pulsed Laser - A method of forming nanometer sized fine particles of functional ceramic from a bulk functional ceramic, particularly fine particles of phosphorous ceramics from a bulk phosphor material is disclosed. The method relies on irradiation of a bulk phosphorous ceramic in a liquid with an ultrashort-pulsed-laser-fragmentation beam to thereby form nanometer sized particles of the phosphorous ceramic. The method is unique in that the generated particles retain the chemical and crystalline properties of the bulk phosphorous ceramic. The generated solutions are stable colloids from which the particles can be isolated or used as is. | 12-12-2013 |
20130293946 | OPTICAL FREQUENCY RULER - The present invention relates to frequency rulers. At least one embodiment includes a mode locked pump source operated at pulse repetition rate, and a pump output having a pump carrier envelope offset frequency. A nonlinear optical system outputs a frequency ruler spectrum comprising individual frequency modes. The frequency modes may be characterized by a frequency spacing which is an integer multiple of the repetition rate and by distinct ruler carrier envelope offset frequencies which exhibit at least one discontinuity across the frequency output. The ruler carrier envelope offset frequencies are substantially locked to the carrier envelope offset frequency of the pump laser. One preferred embodiment includes a frequency doubled, doubly resonant, non-degenerate OPO (DNOPO), a supercontinuum generation (SC) stage and at least one reference laser arranged downstream from a Tm fiber-based pump source. A plurality of beat signals generated therefrom provide for stabilization of the system. | 11-07-2013 |
20130250978 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 09-26-2013 |
20130244100 | IRON PHOSPHATES: NEGATIVE ELECTRODE MATERIALS FOR AQUEOUS RECHARGEABLE SODIUM ION ENERGY STORAGE DEVICES - Various embodiments of the present invention relate to electrode materials based on iron phosphates that can be used as the negative electrode materials for aqueous sodium ion batteries and electrochemical capacitors. At least one embodiment includes a negative electrode material for an aqueous sodium ion based energy storage device. The negative electrode material with a non-olivine crystal structure includes at least one phosphate selected from iron hydroxyl phosphate, Na | 09-19-2013 |
20130194592 | ULTRASHORT LASER MICRO-TEXTURE PRINTING - Systems and methods for providing laser texturing of solid substrates are disclosed. The texturing may be used to provide grayscale images obtainable from substrates, which may include steel, aluminum, glass, and silicon. In some embodiments, images may be obtainable from the substrate by modifying the reflective, diffractive, and/or absorptive features of the substrate or the substrate surface by forming random, periodic, and/or semi-periodic micro-structure features on the substrate (or substrate surface) by an ultrafast laser pulse train. The ultrafast pulse train may be modulated in order to vary, for example, optical exposure time, pulse train intensity, laser polarization, laser wavelength, or a combination of the aforementioned. The ultrafast pulse train and the substrate may be scanned with respect to each other to provide different optical energies to different regions of the substrate (or substrate surface). In some embodiments, the image is provided by making one or more passes of the ultrafast laser pulse train relative to the substrate. | 08-01-2013 |
20130183837 | METHODS AND SYSTEMS FOR LASER PROCESSING OF COATED SUBSTRATES - Examples of methods and systems for laser processing of materials are disclosed. Methods and systems for singulation of a wafer comprising a coated substrate can utilize a laser outputting light that has a wavelength that is transparent to the wafer substrate but which may not be transparent to the coating layer(s). Using techniques for managing fluence and focal condition of the laser beam, the coating layer(s) and the substrate material can be processed through ablation and internal modification, respectively. The internal modification can result in die separation. | 07-18-2013 |
20130183474 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER - A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. This enables clean breaking of transparent materials at a higher speed than conventional techniques. | 07-18-2013 |
20130182724 | OPTICAL PARAMETRIC AMPLIFICATION, OPTICAL PARAMETRIC GENERATION, AND OPTICAL PUMPING IN OPTICAL FIBERS SYSTEMS - Embodiments described herein include a system for producing ultrashort tunable pulses based on ultra broadband OPA or OPG in nonlinear materials. The system parameters such as the nonlinear material, pump wavelengths, quasi-phase matching periods, and temperatures can be selected to utilize the intrinsic dispersion relations for such material to produce bandwidth limited or nearly bandwidth limited pulse compression. Compact high average power sources of short optical pulses tunable in the wavelength range of 1800 to 2100 nm and after frequency doubling in the wavelength range of 900 to 1050 nm can be used as a pump for the ultra broadband OPA or OPG. In certain embodiments, these short pump pulses are obtained from an Er fiber oscillator at about 1550 nm, amplified in Er fiber, Raman-shifted to 1800 to 2100 nm, stretched in a fiber stretcher, and amplified in Tm-doped fiber. | 07-18-2013 |
20130150231 | METHOD OF MANUFACTURING ORDERED INTERMETALLIC CATALYSTS - At least one embodiment includes a method for fabricating a catalyst comprising a colloidal suspension of nanoparticles, the nanoparticles comprising intermetallics of two or more metals exhibiting long range superlattice crystal ordering. The method comprising the steps of: producing a bulk target of the intermetallics of two or more metals exhibiting long range crystal ordering and submerging the target in a solvent. A pulsed laser is used to ablate bulk target material and to produce nanoparticle of the intermetallics of two or more metals exhibiting long range crystal ordering. At least one embodiment includes a catalyst made with the method. The catalyst can exhibit some desirable properties. For example, the catalyst may remain suspended in solution, essentially without surface modification by ionic compounds. Furthermore, the concentration of elements other than those which comprise the solvent or the intermetallic compound may be less than about 1 ppm. | 06-13-2013 |
20130148128 | OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δf | 06-13-2013 |
20130114936 | WIDE BANDWIDTH, LOW LOSS PHOTONIC BANDGAP FIBERS - Various embodiments include photonic bandgap fibers (PBGF). Some PBGF embodiments have a hollow core (HC) and may have a square lattice (SQL). In various embodiments, SQL PBGF can have a cladding region including 2-10 layers of air-holes. In various embodiments, an HC SQL PBGF can be configured to provide a relative wavelength transmission window Δλ/λc larger than about 0.35 and a minimum transmission loss in a range from about 70 dB/km to about 0.1 dB/km. In some embodiments, the HC SQL PBGF can be a polarization maintaining fiber. Methods of fabricating PBGF are also disclosed along with some examples of fabricated fibers. Various applications of PBGF are also described. | 05-09-2013 |
20130114933 | ULTRA HIGH NUMERICAL APERTURE OPTICAL FIBERS - Various embodiments described include optical fiber designs and fabrication processes for ultra high numerical aperture optical fibers (UHNAF) having a numerical aperture (NA) of about 1. Various embodiments of UHNAF may have an NA greater than about 0.7, greater than about 0.8, greater than about 0.9, or greater than about 0.95. Embodiments of UHNAF may have a small core diameter and may have low transmission loss. Embodiments of UHNAF having a sufficiently small core diameter provide single mode operation. Some embodiments have a low V number, for example, less than 2.4 and large dispersion. Some embodiments of UHNAF have extremely large negative dispersion, for example, less than about −300 ps/nm/km in some embodiments. Systems and apparatus using UHNAF are also disclosed. | 05-09-2013 |
20130095260 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER - Methods for ultrashort pulse laser processing of optically transparent materials. A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with side-illumination and not clearly visible without side-illumination. In addition, a method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating. The ultrashort pulse duration causes nonlinear absorption of the laser radiation, and the high repetition rate of the laser causes pulse-to-pulse accumulation of heat within the materials. | 04-18-2013 |
20130093581 | APPARATUS FOR HIGH CONTRAST OPTICAL SIGNALING, AND EXEMPLARY APPLICATIONS - A display apparatus generates a high visibility optical signal, such as an ICON, the ICON comprising a symbol, shape, or other image-like representation. The ICON becomes visible at an observation point during an illumination ON-state. The ICON may be formed as a portion of display medium, for example as a machined portion of a mirror capable of forming images of a scene by reflection in normal operation. The visibility of the ICON in the illumination OFF-state from an observation point is sufficiently low such that the normal operation of the display medium is maintained. The display apparatus may be used in a blind spot warning system for a vehicle. Visible wavelength LEDs, RGB LEDs and/or diode lasers may be utilized as an illumination source. Ultrashort laser processing or other methods for material modification may be utilized to form microscopic features which distribute incident light, increasing the visibility of the optical signal at an observation point in an ON-state, with very low visibility in the OFF-state and minimal effect on the image in the display medium in the OFF state. | 04-18-2013 |
20130089113 | SINGLE MODE PROPAGATION IN FIBERS AND RODS WITH LARGE LEAKAGE CHANNELS - Various embodiments include large cores fibers that can propagate few modes or a single mode while introducing loss to higher order modes. Some of these fibers are holey fibers that comprising cladding features such as air-holes. Additional embodiments described herein include holey rods. The rods and fibers may be used in many optical systems including optical amplification systems, lasers, short pulse generators, Q-switched lasers, etc. and may be used for example for micromachining. | 04-11-2013 |
20130089112 | LARGE CORE HOLEY FIBERS - Holey fibers provide optical propagation. In various embodiments, a large core holey fiber comprises a cladding region formed by large holes arranged in few layers. The number of layers or rows of holes about the large core can be used to coarse tune the leakage losses of the fundamental and higher modes of a signal, thereby allowing the non-fundamental modes to be substantially eliminated by leakage over a given length of fiber. Fine tuning of leakage losses can be performed by adjusting the hole dimension and/or spacing to yield a desired operation with a desired leakage loss of the fundamental mode. Resulting holey fibers have a large hole dimension and spacing, and thus a large core, when compared to traditional fibers and conventional fibers that propagate a single mode. Other loss mechanisms, such as bend loss and modal spacing can be utilized for selected modes of operation of holey fibers. | 04-11-2013 |
20130064256 | CONTROLLABLE MULTI-WAVELENGTH LASER SOURCE - In at least one embodiment a laser system includes a fiber laser source, a polarization controller and a wavelength converter. The relative power distribution between a pump wavelength and a signal wavelength is controllable using the polarization controller. An optional phase compensator is used to control polarization state of the output laser beam. In various embodiments the relative power distribution among multiple wavelengths may be controlled over a range of at least about 100:1. | 03-14-2013 |
20130010818 | SCANNING TEMPORAL ULTRAFAST DELAY AND METHODS AND APPARATUSES THEREFOR - Methods and apparatuses for performing temporal scanning using ultra-short pulse width lasers in which only minimal (micro-scale) mechanical movement is required, and related methods for obtaining high-accuracy timing calibration, on the order of femtoseconds, are disclosed. A dual laser system is disclosed in which the cavity of one or more of the lasers is dithered using a piezoelectric element. A Fabry-Perot etalon generates a sequence of timing pulses used in conjunction with a laser beam produced by the laser having the dithered laser cavity. A correlator correlates a laser pulse from one of the lasers with the sequence of timing pulses to produce a calibrated time scale. The invention is applicable to applications requiring rapid scanning and time calibration, including metrology, characterization of charge dynamics in semiconductors, electro-optic testing of ultrafast electronic and optoelectronic devices, optical time domain reflectometry, and electro-optic sampling oscilloscopes. | 01-10-2013 |
20130003065 | FEMTOSECOND LASER PROCESSING SYSTEM WITH PROCESS PARAMETERS CONTROLS AND FEEDBACK - A femtosecond laser based laser processing system having a femtosecond laser, frequency conversion optics, beam manipulation optics, target motion control, processing chamber, diagnostic systems and system control modules. The femtosecond laser based laser processing system allows for the utilization of the unique heat control in micromachining, and the system has greater output beam stability, continuously variable repetition rate and unique temporal beam shaping capabilities. | 01-03-2013 |
20120327959 | COMPACT OPTICAL FREQUENCY COMB SYSTEMS - Compact optical frequency sources are described. The comb source may include an intra-cavity optical element having a multi-material integrated structure with an electrically controllable active region. The active region may comprise a thin film. By way of example, the thin film and an insulating dielectric material disposed between two electrodes can provide for rapid loss modulation. In some embodiments the thin film may comprise graphene. In various embodiments of a frequency comb laser, rapid modulation of the CEO frequency can be implemented via electric modulation of the transmission or reflection loss of an additional optical element, which can be the saturable absorber itself. In another embodiment, the thin film can also be used as a saturable absorber in order to facilitate passive modelocking. In some implementations the optical element may be formed on a cleaved or polished end of an optical fiber. | 12-27-2012 |
20120314995 | ULTRA SMALL CORE FIBER WITH DISPERSION TAILORING - Various embodiments of optical fiber designs and fabrication processes for ultra small core fibers (USCF) are disclosed. In some embodiments, the USCF includes a core that is at least partially surrounded by a region comprising first features. The USCF further includes a second region at least partially surrounding the first region. The second region includes second features. In an embodiment, the first features are smaller than the second features, and the second features have a filling fraction greater than about 90 percent. The first features and/or the second features may include air holes. Embodiments of the USCF may provide dispersion tailoring. Embodiments of the USCF may be used with nonlinear optical devices configured to provide, for example, a frequency comb or a supercontinuum. | 12-13-2012 |
20120300798 | INEXPENSIVE VARIABLE REP-RATE SOURCE FOR HIGH-ENERGY, ULTRAFAST LASERS - System for converting relatively long pulses from rep-rate variable ultrafast optical sources to shorter, high-energy pulses suitable for sources in high-energy ultrafast lasers. Fibers with positive group velocity dispersion (GVD) and self phase modulation are advantageously employed with the optical sources. These systems take advantage of the need for higher pulse energies at lower repetition rates so that such sources can be cost effective. | 11-29-2012 |
20120282134 | PRODUCTION OF METAL AND METAL-ALLOY NANOPARTICLES WITH HIGH REPETITION RATE ULTRAFAST PULSED LASER ABLATION IN LIQUIDS - Various embodiments include a method of producing chemically pure and stably dispersed metal and metal-alloy nanoparticle colloids with ultrafast pulsed laser ablation. A method comprises irradiating a metal or metal alloy target submerged in a liquid with ultrashort laser pulses at a high repetition rate, cooling a portion of the liquid that includes an irradiated region, and collecting nanoparticles produced with the laser irradiation and liquid cooling. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beams, a metal or metal alloy target submerged in a liquid, and a liquid circulating system to cool the laser focal volume and collect the nanoparticle products. By controlling various laser parameters, and with optional liquid flow movement, the method provides stable colloids of dispersed metal and metal-alloy nanoparticles. In various embodiments additional stabilizing chemical agents are not required. | 11-08-2012 |
20120281720 | BROADBAND GENERATION OF COHERENT CONTINUA WITH OPTICAL FIBERS - Coherent and compact supercontinuum light sources for the mid IR spectral regime and exemplary applications are disclosed based on the use highly nonlinear fibers or waveguides. In at least one embodiment the coherence of the supercontinuum sources is increased using nonlinear material with an elevated vibrational contribution to the nonlinear response function. Compact supercontinuum light sources can be constructed with the use of passively mode locked fiber or diode lasers. Wavelength tunable sources can be constructed using appropriate optical filters or frequency conversion sections. | 11-08-2012 |
20120269212 | INEXPENSIVE VARIABLE REP-RATE SOURCE FOR HIGH-ENERGY, ULTRAFAST LASERS - System for converting relatively long pulses from rep-rate variable ultrafast optical sources to shorter, high-energy pulses suitable for sources in high-energy ultrafast lasers. Fibers with positive group velocity dispersion (GVD) and self phase modulation are advantageously employed with the optical sources. These systems take advantage of the need for higher pulse energies at lower repetition rates so that such sources can be cost effective. | 10-25-2012 |
20120269211 | PULSED LASER SOURCES - Modelocked fiber laser resonators may be coupled with optical amplifiers. An isolator optionally may separate the resonator from the amplifier. A reflective optical element on one end of the resonator having a relatively low reflectivity may be employed to couple light from the resonator to the amplifier. Enhanced pulse-width control may be provided with concatenated sections of both polarization-maintaining and non-polarization-maintaining fibers. Apodized fiber Bragg gratings and integrated fiber polarizers may also be included in the laser cavity to assist in linearly polarizing the output of the cavity. Very short pulses with a large optical bandwidth may be obtained by matching the dispersion value of the grating to the inverse of the dispersion of the intra-cavity fiber. Frequency comb sources may be constructed from such modelocked fiber oscillators. Low dispersion and an in-line interferometer that provides feedback may assist in controlling the frequency components output from the comb source. | 10-25-2012 |
20120257271 | MULTI-CLAD OPTICAL FIBERS - Multi-clad optical fibers and fiber amplifiers are disclosed. Various embodiments include multi-clad, large core fiber amplifiers. In various implementations mixing of pump modes is enhanced relative to that obtainable with conventional double-clad fibers. In some embodiments end terminations are provided with increased length of end-cap fiber. In at least one embodiment a multi-clad fiber is provided, with a pump cladding formed by stacking a layer of low index rods in the preform. Various embodiments include a multi-clad fiber amplifier system. The system includes a pump source to pump said fiber amplifier. The system also includes an optical fiber having a core and a cladding, wherein the cladding includes a pump cladding having a corrugated boundary. In various embodiments the pump cladding is formed by rods in a preform, which are disposed to mix the pump modes and/or scatter or reflect pump energy into the core. | 10-11-2012 |
20120250143 | RARE EARTH DOPED AND LARGE EFFECTIVE AREA OPTICAL FIBERS FOR FIBER LASERS AND AMPLIFIERS - Various embodiments described herein include rare earth doped glass compositions that may be used in optical fiber and rods having large core sizes. Such optical fibers and rods may be employed in fiber lasers and amplifiers. The index of refraction of the glass may be substantially uniform and may be close to that of silica in some embodiments. Possible advantages to such features include reduction of formation of additional waveguides within the core, which becomes increasingly a problem with larger core sizes. | 10-04-2012 |
20120242987 | SURFACE-ENHANCED RAMAN SCATTERING APPARATUS AND METHODS - An apparatus for performing surface-enhanced Raman scattering (SERS) is disclosed wherein an inner surface of a container is coated with SERS active materials such as nanoparticles of noble metals. Such a container can provide a partially enclosed, optical diffuse cavity whose inner surfaces serve for dual purposes of enhancing Raman scattering of the contained analyte and optical integration, therefore improving the efficiency of optical excitation and signal collection. The container may be configured to isolate the SERS active material from the external environment. The container, which may be a cylindrical tube, may be referred to as a SERS tube. Methods of coating the inner wall of a container with pulsed laser ablation and with nanoparticle colloids, respectively, are disclosed. | 09-27-2012 |
20120230353 | OPTICAL PULSE SOURCE WITH INCREASED PEAK POWER - In at least one embodiment time separated pulse pairs are generated, followed by amplification to increase the available peak and/or average power. The pulses are characterized by a time separation that exceeds the input pulse width and with distinct polarization states. The time and polarization discrimination allows easy extraction of the pulses after amplification. In some embodiments polarization maintaining (PM) fibers and/or amplifiers are utilized which provides a compact arrangement. At least one implementation provides for seeding of a solid state amplifier or large core fiber amplifier with time delayed, polarization split pulses, with capability for recombining the time separated pulses at an amplifier output. In various implementations suitable combinations of bulk optics and fibers may be utilized. In some implementations wavelength converted pulse trains are generated. A method and system of the present invention can be used in time domain applications utilizing multiple beam paths, for example spectroscopy. | 09-13-2012 |
20120219020 | ENVIRONMENTALLY STABLE PASSIVELY MODELOCKED FIBER LASER PULSE SOURCE - The present invention is directed to providing an environmentally stable, ultra-short pulse source. Exemplary embodiments relate to passively modelocked ultra-short fiber lasers which are insensitive to temperature variations and which possess only negligible sensitivity to pressure variations. Further, exemplary embodiments can be implemented in a cost-effective manner which render them commercially practical in unlimited applications. Arbitrary fiber lengths (e.g., on the order of 1 millimeter to 1 kilometer, or greater) can be used to provide an ultra-short pulse with a cost-effective architecture which is commercially practical. | 08-30-2012 |
20120212803 | METHOD AND APPARATUS FOR CONTROLLING AND PROTECTING PULSED HIGH POWER FIBER AMPLIFIER SYSTEMS - An electronic circuit for controlling a laser system consisting of a pulse source and high power fiber amplifier is disclosed. The circuit is used to control the gain of the high power fiber amplifier system so that the amplified output pulses have predetermined pulse energy as the pulse width and repetition rate of the oscillator are varied. This includes keeping the pulse energy constant when the pulse train is turned on. The circuitry is also used to control the temperature of the high power fiber amplifier pump diode such that the wavelength of the pump diode is held at the optimum absorption wavelength of the fiber amplifier as the diode current is varied. The circuitry also provides a means of protecting the high power fiber amplifier from damage due to a loss of signal from the pulse source or from a pulse-source signal of insufficient injection energy. | 08-23-2012 |
20120206794 | HIGH POWER PARALLEL FIBER ARRAYS - High power parallel fiber arrays for the amplification of high peak power pulses are described. Fiber arrays based on individual fiber amplifiers as well as fiber arrays based on multi-core fibers can be implemented. The optical phase between the individual fiber amplifier elements of the fiber array is measured and controlled using a variety of phase detection and compensation techniques. High power fiber array amplifiers can be used for EUV and X-ray generation as well as pumping of parametric amplifiers. | 08-16-2012 |
20120205352 | COMPACT, COHERENT, HIGH BRIGHTNESS LIGHT SOURCES FOR THE MID AND FAR IR - Compact high brightness light sources for the mid and far IR spectral region, and exemplary applications are disclosed based on passively mode locked Tm fiber comb lasers. In at least one embodiment the coherence of the comb sources is increased in a system utilizing an amplified single-frequency laser to pump the Tm fiber comb laser. The optical bandwidth generated by the passively mode locked Tm fiber comb laser is further decreased by using simultaneous 2 | 08-16-2012 |
20120200439 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 08-09-2012 |
20120196454 | LASER-BASED MATERIAL PROCESSING METHODS AND SYSTEMS - Various embodiments may be used for laser-based modification of target material of a workpiece while advantageously achieving improvements in processing throughput and/or quality. Embodiments of a method of processing may include focusing and directing laser pulses to a region of the workpiece at a pulse repetition rate sufficiently high so that material is efficiently removed from the region and a quantity of unwanted material within the region, proximate to the region, or both is reduced relative to a quantity obtainable at a lower repetition rate. Embodiments of an ultrashort pulse laser system may include a fiber amplifier or fiber laser. Various embodiments are suitable for at least one of dicing, cutting, scribing, and forming features on or within a semiconductor substrate. Workpiece materials may include metals, inorganic or organic dielectrics, or any material to be micromachined with femtosecond, picosecond, and/or nanosecond pulses. | 08-02-2012 |
20120195330 | METHODS AND SYSTEMS FOR FIBER DELIVERY OF HIGH PEAK POWER OPTICAL PULSES - Methods and systems for delivery of high peak power optical pulses through optical fiber are disclosed. Raman soliton generation is utilized to maintain the properties of the pulses in the delivery fiber. The apparatus can comprise any high peak power pulse source and delivery fiber supporting Raman soliton generation. | 08-02-2012 |
20120188632 | GLASS LARGE-CORE OPTICAL FIBERS - Embodiments of optical fiber may include cladding features that include a material (e.g., fluorine-doped silica glass) that may produce a very low relative refractive index difference with respect to cladding material in which the cladding features are disposed. This relative refractive index difference may be characterized by (n | 07-26-2012 |
20120168669 | COMPOSITE NANOPARTICLES AND METHODS FOR MAKING THE SAME - A composite nanoparticle, for example a nanoparticle containing one or a plurality of cores embedded in another material. A composite nanoparticle can be formed by a one step process that includes: ejecting material from a bulk target material using physical energy source, with the bulk target material disposed in a liquid. Composite nanoparticles are formed by cooling at least a portion of the ejected material in the liquid. The composite fine particles may then be collected from the liquid. A product that includes composite fine particles may be formed with laser ablation, and ultrashort laser ablation may be utilized so as to preserve composite nanoparticle stoichiometry. For applications of the composite fine particles, optical properties and/or magnetic properties may be exploited for various applications. | 07-05-2012 |
20120162748 | COMPACT, HIGH BRIGHTNESS LIGHT SOURCES FOR THE MID AND FAR IR - Compact laser systems are disclosed which include ultrafast laser sources in combination with nonlinear crystals or waveguides. In some implementations fiber based mid-IR sources producing very short pulses and/or mid-IR sources based on a mode locked fiber lasers are utilized. Some embodiments may include an infrared source with an amplifier system comprising, in combination, a Tm fiber amplifier and an Er fiber amplifier. A difference frequency generator receives outputs from the Er and/or Tm amplifier system, and generates an output comprising a difference frequency. Exemplary applications of the compact, high brightness mid-IR light sources include medical applications, spectroscopy, ranging, sensing and metrology. | 06-28-2012 |
20120148756 | METHOD OF PRODUCING COMPOUND NANORODS AND THIN FILMS - A method of producing compound nanorods and thin films under a controlled growth mode is described. The method involves ablating compound targets using an ultrafast pulsed laser and depositing the ablated materials onto a substrate. When producing compound nanorods, external catalysts such as pre-deposited metal nanoparticles are not involved. Instead, at the beginning of deposition, simply by varying the fluence at the focal spot on the target, a self-formed seed layer can be introduced for nanorods growth. This provides a simple method of producing high purity nanorods and controlling the growth mode. Three growth modes are covered by the present invention, including nanorod growth, thin film growth, and nano-porous film growth. | 06-14-2012 |
20120145902 | OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δf | 06-14-2012 |
20120140378 | RECHARGEABLE ELECTROCHEMICAL ENERGY STORAGE DEVICE - A rechargeable energy storage device is disclosed. In at least one embodiment the energy storage device includes an air electrode providing an electrochemical process comprising reduction and evolution of oxygen and a capacitive electrode enables an electrode process consisting of non-faradic reactions based on ion absorption/desorption and/or faradic reactions. This rechargeable energy storage device is a hybrid system of fuel cells and ultracapacitors, pseudocapacitors, and/or secondary batteries. | 06-07-2012 |
20120133931 | FREQUENCY COMB SOURCE WITH LARGE COMB SPACING - A frequency comb laser providing large comb spacing is disclosed. At least one embodiment includes a mode locked waveguide laser system. The mode locked waveguide laser includes a laser cavity having a waveguide, and a dispersion control unit (DCU) in the cavity. The DCU imparts an angular dispersion, group-velocity dispersion (GVD) and a spatial chirp to a beam propagating in the cavity. The DCU is capable of producing net GVD in a range from a positive value to a negative value. In some embodiments a tunable fiber frequency comb system configured as an optical frequency synthesizer is provided. In at least one embodiment a low phase noise micro-wave source may be implemented with a fiber comb laser having a comb spacing greater than about 1 GHz. The laser system is suitable for mass-producible fiber comb sources with large comb spacing and low noise. Applications include high-resolution spectroscopy. | 05-31-2012 |
20120120971 | YB: AND ND: MODE-LOCKED OSCILLATORS AND FIBER SYSTEMS INCORPORATED IN SOLID-STATE SHORT PULSE LASER SYSTEMS - The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier. | 05-17-2012 |
20120099609 | SINGLE MODE PROPAGATION IN FIBERS AND RODS WITH LARGE LEAKAGE CHANNELS - Various embodiments include large cores fibers that can propagate few modes or a single mode while introducing loss to higher order modes. Some of these fibers are holey fibers that comprising cladding features such as air-holes. Additional embodiments described herein include holey rods. The rods and fibers may be used in many optical systems including optical amplification systems, lasers, short pulse generators, Q-switched lasers, etc. and may be used for example for micromachining. | 04-26-2012 |
20120093469 | ULTRA HIGH NUMERICAL APERTURE OPTICAL FIBERS - Various embodiments described include optical fiber designs and fabrication processes for ultra high numerical aperture optical fibers (UHNAF) having a numerical aperture (NA) of about 1. Various embodiments of UHNAF may have an NA greater than about 0.7, greater than about 0.8, greater than about 0.9, or greater than about 0.95. Embodiments of UHNAF may have a small core diameter and may have low transmission loss. Embodiments of UHNAF having a sufficiently small core diameter provide single mode operation. Some embodiments have a low V number, for example, less than 2.4 and large dispersion. Some embodiments of UHNAF have extremely large negative dispersion, for example, less than about −300 ps/nm/km in some embodiments. Systems and apparatus using UHNAF are also disclosed. | 04-19-2012 |
20120081694 | OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δf | 04-05-2012 |
20120062983 | OPTICAL PARAMETRIC AMPLIFICATION, OPTICAL PARAMETRIC GENERATION, AND OPTICAL PUMPING IN OPTICAL FIBERS SYSTEMS - Embodiments described herein include a system for producing ultrashort tunable pulses based on ultra broadband OPA or OPG in nonlinear materials. The system parameters such as the nonlinear material, pump wavelengths, quasi-phase matching periods, and temperatures can be selected to utilize the intrinsic dispersion relations for such material to produce bandwidth limited or nearly bandwidth limited pulse compression. Compact high average power sources of short optical pulses tunable in the wavelength range of 1800-2100 nm and after frequency doubling in the wavelength range of 900-1050 nm can be used as a pump for the ultra broadband OPA or OPG. In certain embodiments, these short pump pulses are obtained from an Er fiber oscillator at about 1550 nm, amplified in Er fiber, Raman-shifted to 1800-2100 nm, stretched in a fiber stretcher, and amplified in Tm-doped fiber. | 03-15-2012 |
20120008649 | HIGH POWER SHORT PULSE FIBER LASER - A pulsed laser comprises an oscillator and amplifier. An attenuator and/or pre-compressor may be disposed between the oscillator and amplifier to improve performance and possibly the quality of pulses output from the laser. Such pre-compression may be implemented with spectral filters and/or dispersive elements between the oscillator and amplifier. The pulsed laser may have a modular design comprising modular devices that may have Telcordia-graded quality and reliability. Fiber pigtails extending from the device modules can be spliced together to form laser system. In one embodiment, a laser system operating at approximately 1050 nm comprises an oscillator having a spectral bandwidth of approximately 19 nm. This oscillator signal can be manipulated to generate a pulse having a width below approximately 90 fs. | 01-12-2012 |
20120003395 | METHOD OF FABRICATING AN ELECTROCHEMICAL DEVICE USING ULTRAFAST PULSED LASER DEPOSITION - A method of fabricating a multi-layered thin film electrochemical device is provided. The method comprises: providing a first target material in a chamber; providing a substrate in the chamber; emitting a first intermittent laser beam directed at the first target material to generate a first plasma, wherein each pulse of the first intermittent laser beam has a pulse duration of about 20 fs to about 500 ps; depositing the first plasma on the substrate to form a first thin film; providing a second target material in the chamber; emitting a second intermittent laser beam directed at the second target material to generate a second plasma, wherein each pulse of the second intermittent laser beam has a pulse duration of about 20 fs to about 500 ps; and depositing the second plasma on or above the first thin film to form a second thin film. | 01-05-2012 |
20110280262 | MODULAR, HIGH ENERGY, WIDELY-TUNABLE ULTRAFAST FIBER SOURCE - A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Modularity is ensured by the implementation of interchangeable amplifier components. System compactness is ensured by employing efficient fiber amplifiers, directly or indirectly pumped by diode lasers. Peak power handling capability of the fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses. Dispersive broadening is introduced by dispersive pulse stretching in the presence of self-phase modulation and gain, resulting in the formation of high-power parabolic pulses. In addition, dispersive broadening is also introduced by simple fiber delay lines or chirped fiber gratings, resulting in a further increase of the energy handling ability of the fiber amplifiers. The phase of the pulses in the dispersive delay line is controlled to quartic order by the use of fibers with varying amounts of waveguide dispersion or by controlling the chirp of the fiber gratings. After amplification, the dispersively stretched pulses can be re-compressed to nearly their bandwidth limit by the implementation of another set of dispersive delay lines. To ensure a wide tunability of the whole system, Raman-shifting of the compact sources of ultrashort pulses in conjunction with frequency-conversion in nonlinear optical crystals can be implemented, or an Anti-Stokes fiber in conjunction with fiber amplifiers and Raman-shifters are used. A particularly compact implementation of the whole system uses fiber oscillators in conjunction with fiber amplifiers. Additionally, long, distributed, positive dispersion optical amplifiers are used to improve transmission characteristics of an optical communication system. Finally, an optical communication system utilizes a Raman amplifier fiber pumped by a train of Raman-shifted, wavelength-tunable pump pulses, to thereby amplify an optical signal which counterpropogates within the Raman amplifier fiber with respect to the pump pulses. | 11-17-2011 |
20110240617 | LASER-BASED MATERIAL PROCESSING APPARATUS AND METHODS - Various embodiments may be used for laser-based modification of target material of a workpiece while advantageously achieving improvements in processing throughput and/or quality. Embodiments of a method of processing may include focusing and directing laser pulses to a region of the workpiece at a pulse width sufficiently short so that material is efficiently removed by nonlinear optical absorption from the region and a quantity of heat affected zone and thermal stress on the material within the region, proximate to the region, or both is reduced relative to a quantity obtainable using a laser with longer pulses. In at least one embodiment, an ultrashort pulse laser system may include at least one of a fiber amplifier or fiber laser. Various embodiments are suitable for at least one of dicing, cutting, scribing, and forming features on or within a composite material. | 10-06-2011 |
20110200061 | UTILIZATION OF YB: AND ND: MODE-LOCKED OSCILLATORS IN SOLID-STATE SHORT PULSE LASER SYSTEMS - An optimized Yb: doped fiber mode-locked oscillator and fiber amplifier system for seeding Nd: or Yb: doped regenerative amplifiers. The pulses are generated in the Yb: or Nd: doped fiber mode-locked oscillator, and may undergo spectral narrowing or broadening, wavelength converting, temporal pulse compression or stretching, pulse attenuation and/or lowering the repetition rate of the pulse train. The conditioned pulses are subsequently coupled into an Yb: or Nd: fiber amplifier. The amplified pulses are stretched before amplification in the regenerative amplifier that is based on an Nd: or Yb: doped solid-state laser material, and then recompressed for output. | 08-18-2011 |
20110170565 | RESONANT FABRY-PEROT SEMICONDUCTOR SATURABLE ABSORBERS AND TWO PHOTON ABSORPTION POWER LIMITERS - An intracavity resonant Fabry-Perot saturable absorber (R-FPSA) induces modelocking in a laser such as a fiber laser. An optical limiter such as a two photon absorber (TPA) can be used in conjunction with the R-FPSA, so that Q-switching is inhibited, resulting in laser output that is cw modelocked. By using both an R-FPSA and a TPA, the Q-switched modelocked behavior of a fiber laser is observed to evolve into cw modelocking. | 07-14-2011 |
20110147620 | LASER PATTERNING USING A STRUCTURED OPTICAL ELEMENT AND FOCUSED BEAM - Various embodiments provide for laser patterning using a structured optical element and a focused beam. In some embodiments a structured optical element may be integrally formed on a single substrate. In some embodiments, multiple optical components may be combined in an optical path to provide a desired pattern. In at least one embodiment, a projection mask is utilized to control exposure of an object to a laser output, in combination with the controlled motion of the projection mask, the controlled motion of the object and the controlled motion of the laser beam. In some embodiments, a projection mask is utilized to control exposure of an object, and the projection mask may absorb, scatter, reflect, or attenuate a laser output. In some embodiments, the projection mask may include optical elements that vary the optical power and polarization of the transmitted laser beam over regions of the projection mask. In various embodiments, the laser system may modify material of the object. In various embodiments, the laser system may be used to probe a physical property of an object. | 06-23-2011 |
20110141555 | AUTO-CLADDED LARGE-CORE OPTICAL FIBERS - Embodiments of auto-cladded optical fibers are described. The fibers may have a refractive index profile having a small relative refractive index change. For example, the fiber may include an auto-cladded structure having, e.g., a trough or gradient in the refractive index profile. A beam of light propagating in the fiber may be guided, at least in part, with the auto-cladded structure. In some embodiments, the optical fiber may be all glass. In some embodiments, the optical fiber may include a large-core or an ultra large-core. | 06-16-2011 |
20110139760 | FEMTOSECOND LASER PROCESSING SYSTEM WITH PROCESS PARAMETERS CONTROLS AND FEEDBACK - A femtosecond laser based laser processing system having a femtosecond laser, frequency conversion optics, beam manipulation optics, target motion control, processing chamber, diagnostic systems and system control modules. The femtosecond laser based laser processing system allows for the utilization of the unique heat control in micromachining, and the system has greater output beam stability, continuously variable repetition rate and unique temporal beam shaping capabilities. | 06-16-2011 |
20110134943 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 06-09-2011 |
20110133129 | METHOD OF TUNING PROPERTIES OF THIN FILMS - A method of tuning thin film properties using pulsed laser deposition (PLD) by tuning laser parameters is provided. Various embodiments may be utilized to tune magnetic properties, conductivity or other physical properties. Some embodiments may improve performance of electrochemical devices, for example a thin film electrode may be fabricated resulting in improved reaction speed of a Li ion battery. By way of example, a material property of thin film is tuned by setting a pulse duration. In some embodiments the numbers of laser pulses and laser pulse energy are other laser parameters which may be utilized to tune the film properties. The materials that can be synthesized using various embodiments of the invention include, but are not limited to, metals and metal oxides. | 06-09-2011 |
20110103408 | BEAM STABILIZED FIBER LASER - A laser head generating ultrashort pulses is integrated with an active beam steering device in the head. Direct linkage with an application system by means of an adequate interface protocol enables the active device to be controlled directly by the application system. | 05-05-2011 |
20110085769 | WIDE BANDWIDTH, LOW LOSS PHOTONIC BANDGAP FIBERS - Various embodiments include photonic bandgap fibers (PBGF). Some PBGF embodiments have a hollow core (HC) and may have a square lattice (SQL). In various embodiments, SQL PBGF can have a cladding region including 2-10 layers of air-holes. In various embodiments, an HC SQL PBGF can be configured to provide a relative wavelength transmission window Δλ/λc larger than about 0.35 and a minimum transmission loss in a range from about 70 dB/km to about 0.1 dB/km. In some embodiments, the HC SQL PBGF can be a polarization maintaining fiber. Methods of fabricating PBGF are also disclosed along with some examples of fabricated fibers. Various applications of PBGF are also described. | 04-14-2011 |
20110080580 | OPTICAL SIGNAL PROCESSING WITH MODELOCKED LASERS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. In some embodiments an effective CDSL is constructed with only one laser. At least one embodiment includes a coherent scanning laser system (CSL) for generating pulse pairs with a time varying time delay. A CDSL, effective CDSL, or CSL may be arranged in an imaging system for one or more of optical imaging, microscopy, micro-spectroscopy and/or THz imaging. | 04-07-2011 |
20110069723 | HIGHLY RARE-EARTH-DOPED OPTICAL FIBERS FOR FIBER LASERS AND AMPLIFIERS - Various embodiments described herein comprise a laser and/or an amplifier system including a doped gain fiber having ytterbium ions in a phosphosilicate glass. Various embodiments described herein increase pump absorption to at least about 1000 dB/m-9000 dB/m. The use of these gain fibers provide for increased peak-powers and/or pulse energies. The various embodiments of the doped gain fiber having ytterbium ions in a phosphosilicate glass exhibit reduced photo-darkening levels compared to photo-darkening levels obtainable with equivalent doping levels of an ytterbium doped silica fiber. | 03-24-2011 |
20110020008 | PHOTONIC BANDGAP FIBERS - Included among the many structures described herein are photonic bandgap fibers designed to provide a desired dispersion spectrum. Additionally, designs for achieving wide transmission bands and lower transmission loss are also discussed. For example, in some fiber designs, smaller dimensions of high index material in the cladding and large core size provide small flat dispersion over a wide spectral range. In other examples, the thickness of the high index ring-shaped region closest to the core has sufficiently large dimensions to provide negative dispersion or zero dispersion at a desired wavelength. Additionally, low index cladding features distributed along concentric rings or circles may be used for achieving wide bandgaps. | 01-27-2011 |
20100329618 | RARE EARTH DOPED AND LARGE EFFECTIVE AREA OPTICAL FIBERS FOR FIBER LASERS AND AMPLIFIERS - Various embodiments described herein include rare earth doped glass compositions that may be used in optical fiber and rods having large core sizes. Such optical fibers and rods may be employed in fiber lasers and amplifiers. The index of refraction of the glass may be substantially uniform and may be close to that of silica in some embodiments. Possible advantages to such features include reduction of formation of additional waveguides within the core, which becomes increasingly a problem with larger core sizes. | 12-30-2010 |
20100322575 | SINGLE MODE PROPAGATION IN FIBERS AND RODS WITH LARGE LEAKAGE CHANNELS - Various embodiments include large cores fibers that can propagate few modes or a single mode while introducing loss to higher order modes. Some of these fibers are holey fibers that comprising cladding features such as air-holes. Additional embodiments described herein include holey rods. The rods and fibers may be used in many optical systems including optical amplification systems, lasers, short pulse generators, Q-switched lasers, etc. and may be used for example for micromachining. | 12-23-2010 |
20100272129 | YB: AND ND: MODE-LOCKED OSCILLATORS AND FIBER SYSTEMS INCORPORATED IN SOLID-STATE SHORT PULSE LASER SYSTEMS - The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier. | 10-28-2010 |
20100265972 | LASER BASED FREQUENCY STANDARDS AND THEIR APPLICATIONS - Frequency standards based on mode-locked fiber lasers, fiber amplifiers and fiber-based ultra-broad bandwidth light sources, and applications of the same. | 10-21-2010 |
20100260214 | SINGLE-POLARIZATION HIGH POWER FIBER LASERS AND AMPLIFIERS - A novel polarization maintaining optical fiber, which can be used as a high-power polarization maintaining fiber laser or amplifier, is described. Insensitivity of the polarization state to external fiber bending and temperature changes is accomplished by minimizing polarization mode-coupling via reducing stresses inside the fiber core via increasing the fiber diameter. Alternatively, polarization mode-coupling can be minimized by an optimization of the fiber coating to minimize stresses at the interface between the fiber and the coating. As a result insensitivity to polarization mode-coupling is obtained at greatly reduced values of birefringence compared to small-diameter fibers. The fiber is of significant use in any application where polarization stability is important, and will be useful in telecommunications applications in particular for reducing polarization mode dispersion. An implementation in a parabolic pulse-producing fiber laser is also described as one specific high power example. | 10-14-2010 |
20100247046 | WIDE BANDWIDTH, LOW LOSS PHOTONIC BANDGAP FIBERS - Various embodiments described herein comprise hollow core (HC) photonic bandgap fibers (PBGF) with a square lattice (SQL). In various embodiments the, HC SQL PBGF includes a cladding region comprising 2-10 layers of air-holes. In various embodiments, the HC SQL PBGF can be configured to provide a relative wavelength transmission window Δλ/λc larger than about 0.35 and minimum transmission loss in a range from about 70 dB/km to about 0.1 dB/km. In some embodiments, the HC SQL PBGF fiber can be a polarization maintaining fiber. Methods of fabricating such fibers are also disclosed herein along with some examples of fabricated fibers. Various applications of such fibers are also described herein. | 09-30-2010 |
20100227133 | PULSED LASER MICRO-DEPOSITION PATTERN FORMATION - A method of forming patterns on transparent substrates using a pulsed laser is disclosed. Various embodiments include an ultrashort pulsed laser, a substrate that is transparent to the laser wavelength, and a target plate. The laser beam is guided through the transparent substrate and focused on the target surface. The target material is ablated by the laser and is deposited on the opposite substrate surface. A pattern, for example a gray scale image, is formed by scanning the laser beam relative to the target. Variations of the laser beam scan speed and scan line density control the material deposition and change the optical properties of the deposited patterns, creating a visual effect of gray scale. In some embodiments patterns may be formed on a portion of a microelectronic device during a fabrication process. In some embodiments high repetition rate picoseconds and nanosecond sources are configured to produce the patterns. | 09-09-2010 |
20100225897 | OPTICAL SCANNING AND IMAGING SYSTEMS BASED ON DUAL PULSED LASER SYSTEMS - The invention relates to scanning pulsed laser systems for optical imaging. Coherent dual scanning laser systems (CDSL) are disclosed and some applications thereof. Various alternatives for implementation are illustrated, including highly integrated configurations. In at least one embodiment a coherent dual scanning laser system (CDSL) includes two passively modelocked fiber oscillators. The oscillators are configured to operate at slightly different repetition rates, such that a difference δf | 09-09-2010 |
20100209700 | METHOD OF PRODUCING COMPOUND NANORODS AND THIN FILMS - A method of producing compound nanorods and thin films under a controlled growth mode is described. The method involves ablating compound targets using an ultrafast pulsed laser and depositing the ablated materials onto a substrate. When producing compound nanorods, external catalysts such as pre-deposited metal nanoparticles are not involved. Instead, at the beginning of deposition, simply by varying the fluence at the focal spot on the target, a self-formed seed layer can be introduced for nanorods growth. This provides a simple method of producing high purity nanorods and controlling the growth mode. Three growth modes are covered by the present invention, including nanorod growth, thin film growth, and nano-porous film growth. | 08-19-2010 |
20100197116 | LASER-BASED MATERIAL PROCESSING METHODS AND SYSTEMS - Various embodiments may be used for laser-based modification of target material of a workpiece while advantageously achieving improvements in processing throughput and/or quality. Embodiments of a method of processing may include focusing and directing laser pulses to a region of the workpiece at a pulse repetition rate sufficiently high so that material is efficiently removed from the region and a quantity of unwanted material within the region, proximate to the region, or both is reduced relative to a quantity obtainable at a lower repetition rate. In at least one embodiment, an ultrashort pulse laser system may include at least one of a fiber amplifier or fiber laser. Various embodiments are suitable for at least one of dicing, cutting, scribing, and forming features on or within a semiconductor substrate. Workpiece materials may also include metals, inorganic or organic dielectrics, or any material to be micromachined with femtosecond and/or picosecond pulses, and in some embodiments with pulse widths up to a few nanoseconds. | 08-05-2010 |
20100196192 | Production of metal and metal-alloy nanoparticles with high repetition rate ultrafast pulsed laser ablation in liquids - Various embodiments include a method of producing chemically pure and stably dispersed metal and metal-alloy nanoparticle colloids with ultrafast pulsed laser ablation. A method comprises irradiating a metal or metal alloy target submerged in a liquid with ultrashort laser pulses at a high repetition rate, cooling a portion of the liquid that includes an irradiated region, and collecting nanoparticles produced with the laser irradiation and liquid cooling. The method may be implemented with a high repetition rate ultrafast pulsed laser source, an optical system for focusing and moving the pulsed laser beams, a metal or metal alloy target submerged in a liquid, and a liquid circulating system to cool the laser focal volume and collect the nanoparticle products. By controlling various laser parameters, and with optional liquid flow movement, the method provides stable colloids of dispersed metal and metal-alloy nanoparticles. In various embodiments additional stabilizing chemical agents are not required. | 08-05-2010 |
20100195677 | PULSED LASER SOURCES - Various embodiments include modelocked fiber laser resonators that may be coupled with optical amplifiers. An isolator may separate the laser resonator from the amplifier, although certain embodiments exclude such an isolator. A reflective optical element on one end of the resonator having a relatively low reflectivity may be employed to couple light from the laser resonator to the amplifier. Enhanced pulse-width control may be provided with concatenated sections of both polarization-maintaining and non-polarization-maintaining fibers. Apodized fiber Bragg gratings and integrated fiber polarizers may be also be included in the laser cavity to assist in linearly polarizing the output of the cavity. Very short pulses with a large optical bandwidth may be obtained by matching the dispersion value of the fiber Bragg grating to the inverse of the dispersion of the intra-cavity fiber. Frequency comb sources may be constructed from such modelocked fiber oscillators. In various exemplary embodiments, low dispersion and an in-line interferometer that provides feedback, assist in controlling the frequency components output from the comb source. | 08-05-2010 |
20100189390 | ULTRA HIGH NUMERICAL APERTURE OPTICAL FIBERS - Various embodiments described include optical fiber designs and fabrication processes for ultra high numerical aperture optical fibers (UHNAF) having a numerical aperture (NA) of about 1. Various embodiments of UHNAF may have an NA greater than about 0.7, greater than about 0.8, greater than about 0.9, or greater than about 0.95. Embodiments of UHNAF may have a small core diameter and may have low transmission loss. Embodiments of UHNAF having a sufficiently small core diameter provide single mode operation. Some embodiments have a low V number, for example, less than 2.4 and large dispersion. Some embodiments of UHNAF have extremely large negative dispersion, for example, less than about −300 ps/nm/km in some embodiments. Systems and apparatus using UHNAF are also disclosed. | 07-29-2010 |
20100188736 | MODULAR FIBER-BASED CHIRPED PULSE AMPLIFICATION SYSTEM - A modular ultrafast pulse laser system is constructed of individually pre-tested components manufactured as modules. The individual modules include an oscillator, pre-amplifier and power amplifier stages, a non-linear amplifier, and a stretcher and compressor. The individual modules can typically be connected by means of simple fiber splices. | 07-29-2010 |
20100157418 | GLASS LARGE-CORE OPTICAL FIBERS - Embodiments of optical fiber may include cladding features that include a material (e.g., fluorine-doped silica glass) that may produce a very low relative refractive index difference with respect to cladding material in which the cladding features are disposed. This relative refractive index difference may be characterized by (n | 06-24-2010 |
20100111120 | PULSED LASER SOURCE WITH ADJUSTABLE GRATING COMPRESSOR - Various embodiments described herein relate to a laser source for producing a pulsed laser beam comprising a plurality of ultrashort optical pulses having a variable repetition rate. In one embodiment, the laser source comprises a fiber oscillator, which outputs optical pulses and a pulse stretcher disposed to receive the optical pulses. The optical pulses have an optical pulse width. The pulse stretcher has dispersion that increases the optical pulse width yielding stretched optical pulses. The laser source further comprises a fiber amplifier disposed to receive the stretched optical pulses. The fiber optical amplifier has gain so as to amplify the stretched optical pulses. The laser source includes an automatically adjustable grating compressor having dispersion that reduces the optical pulse width. The grating compressor automatically adjusts this dispersion for different repetition rates. | 05-06-2010 |
20100110537 | MICROCHIP-Yb FIBER HYBRID OPTICAL AMPLIFIER FOR MICRO-MACHINING AND MARKING - The invention describes techniques for the control of the spatial as well as spectral beam quality of multi-mode fiber amplification of high peak power pulses as well as using such a configuration to replace the present diode-pumped, Neodynium based sources. Perfect spatial beam-quality can be ensured by exciting the fundamental mode in the multi-mode fibers with appropriate mode-matching optics and techniques. The loss of spatial beam-quality in the multi-mode fibers along the fiber length can be minimized by using multi-mode fibers with large cladding diameters. Near diffraction-limited coherent multi-mode amplifiers can be conveniently cladding pumped, allowing for the generation of high average power. Moreover, the polarization state in the multi-mode fiber amplifiers can be preserved by implementing multi-mode fibers with stress producing regions or elliptical fiber cores These lasers find application as a general replacement of Nd: based lasers, especially Nd:YAG lasers. Particularly utility is disclosed for applications in the marking, micro-machining and drilling areas. | 05-06-2010 |
20100086741 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER - Methods for ultrashort pulse laser processing of optically transparent materials. A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. This enables clean breaking of transparent materials at a higher speed than conventional techniques. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with side-illumination and not clearly visible without side-illumination. In addition, a method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating. The ultrashort pulse duration causes nonlinear absorption of the laser radiation, and the high repetition rate of the laser causes pulse-to-pulse accumulation of heat within the materials. The laser is focused near the interface of the materials, generating a high energy fluence at the region to be welded. This minimizes damage to the rest of the material and enables fine weld lines. | 04-08-2010 |
20100084384 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER - Methods for ultrashort pulse laser processing of optically transparent materials. A method for scribing transparent materials uses ultrashort laser pulses to create multiple scribe features with a single pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. This enables clean breaking of transparent materials at a higher speed than conventional techniques. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with side-illumination and not clearly visible without side-illumination. In addition, a method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating. The ultrashort pulse duration causes nonlinear absorption of the laser radiation, and the high repetition rate of the laser causes pulse-to-pulse accumulation of heat within the materials. The laser is focused near the interface of the materials, generating a high energy fluence at the region to be welded. This minimizes damage to the rest of the material and enables fine weld lines. | 04-08-2010 |
20100074279 | ENVIRONMENTALLY STABLE PASSIVELY MODELOCKED FIBER LASER PULSE SOURCE - The present invention is directed to providing an environmentally stable, ultra-short pulse source. Exemplary embodiments relate to passively modelocked ultra-short fiber lasers which are insensitive to temperature variations and which possess only negligible sensitivity to pressure variations. Further, exemplary embodiments can be implemented in a cost-effective manner which render them commercially practical in unlimited applications. Arbitrary fiber lengths (e.g., on the order of 1 millimeter to 1 kilometer, or greater) can be used to provide an ultra-short pulse with a cost-effective architecture which is commercially practical. | 03-25-2010 |
20100060978 | METHOD AND APPARATUS FOR CONTROLLING AND PROTECTING PULSED HIGH POWER FIBER AMPLIFIER SYSTEMS - An electronic circuit for controlling a laser system consisting of a pulse source and high power fiber amplifier is disclosed. The circuit is used to control the gain of the high power fiber amplifier system so that the amplified output pulses have predetermined pulse energy as the pulse width and repetition rate of the oscillator are varied. This includes keeping the pulse energy constant when the pulse train is turned on. The circuitry is also used to control the temperature of the high power fiber amplifier pump diode such that the wavelength of the pump diode is held at the optimum absorption wavelength of the fiber amplifier as the diode current is varied. The circuitry also provides a means of protecting the high power fiber amplifier from damage due to a loss of signal from the pulse source or from a pulse-source signal of insufficient injection energy. | 03-11-2010 |
20100046067 | MODULAR, HIGH ENERGY, WIDELY-TUNABLE ULTRAFAST FIBER SOURCE - A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Modularity is ensured by the implementation of interchangeable amplifier components. System compactness is ensured by employing efficient fiber amplifiers, directly or indirectly pumped by diode lasers. Peak power handling capability of the fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses. Dispersive broadening is introduced by dispersive pulse stretching in the presence of self-phase modulation and gain, resulting in the formation of high-power parabolic pulses. In addition, dispersive broadening is also introduced by simple fiber delay lines or chirped fiber gratings, resulting in a further increase of the energy handling ability of the fiber amplifiers. The phase of the pulses in the dispersive delay line is controlled to quartic order by the use of fibers with varying amounts of waveguide dispersion or by controlling the chirp of the fiber gratings. After amplification, the dispersively stretched pulses can be re-compressed to nearly their bandwidth limit by the implementation of another set of dispersive delay lines. To ensure a wide tunability of the whole system, Raman-shifting of the compact sources of ultrashort pulses in conjunction with frequency-conversion in nonlinear optical crystals can be implemented, or an Anti-Stokes fiber in conjunction with fiber amplifiers and Raman-shifters are used. A particularly compact implementation of the whole system uses fiber oscillators in conjunction with fiber amplifiers. Additionally, long, distributed, positive dispersion optical amplifiers are used to improve transmission characteristics of an optical communication system. Finally, an optical communication system utilizes a Raman amplifier fiber pumped by a train of Raman-shifted, wavelength-tunable pump pulses, to thereby amplify an optical signal which counterpropogates within the Raman amplifier fiber with respect to the pump pulses. | 02-25-2010 |
20100046066 | MODULAR, HIGH ENERGY, WIDELY-TUNABLE ULTRAFAST FIBER SOURCE - A modular, compact and widely tunable laser system for the efficient generation of high peak and high average power ultrashort pulses. Modularity is ensured by the implementation of interchangeable amplifier components. System compactness is ensured by employing efficient fiber amplifiers, directly or indirectly pumped by diode lasers. Peak power handling capability of the fiber amplifiers is expanded by using optimized pulse shapes, as well as dispersively broadened pulses. Dispersive broadening is introduced by dispersive pulse stretching in the presence of self-phase modulation and gain, resulting in the formation of high-power parabolic pulses. In addition, dispersive broadening is also introduced by simple fiber delay lines or chirped fiber gratings, resulting in a further increase of the energy handling ability of the fiber amplifiers. The phase of the pulses in the dispersive delay line is controlled to quartic order by the use of fibers with varying amounts of waveguide dispersion or by controlling the chirp of the fiber gratings. After amplification, the dispersively stretched pulses can be re-compressed to nearly their bandwidth limit by the implementation of another set of dispersive delay lines. To ensure a wide tunability of the whole system, Raman-shifting of the compact sources of ultrashort pulses in conjunction with frequency-conversion in nonlinear optical crystals can be implemented, or an Anti-Stokes fiber in conjunction with fiber amplifiers and Raman-shifters are used. A particularly compact implementation of the whole system uses fiber oscillators in conjunction with fiber amplifiers. Additionally, long, distributed, positive dispersion optical amplifiers are used to improve transmission characteristics of an optical communication system. Finally, an optical communication system utilizes a Raman amplifier fiber pumped by a train of Raman-shifted, wavelength-tunable pump pulses, to thereby amplify an optical signal which counterpropogates within the Raman amplifier fiber with respect to the pump pulses. | 02-25-2010 |
20100025387 | TRANSPARENT MATERIAL PROCESSING WITH AN ULTRASHORT PULSE LASER - Methods, devices, and systems for ultrashort pulse laser processing of optically transparent materials are disclosed, with example applications in scribing, marking, welding, and joining. For example, ultrashort laser pulses create scribe features with one pass of the laser beam across the material, with at least one of the scribe features being formed below the surface of the material. Slightly modifying the ultrashort pulse laser processing conditions produces sub-surface marks. When properly arranged, these marks are clearly visible with correctly aligned illumination. Reflective marks may also be formed with control of laser parameters. A transparent material other than glass may be utilized. A method for welding transparent materials uses ultrashort laser pulses to create a bond through localized heating. In some embodiments of transparent material processing, a multifocus beam generator simultaneously forms multiple beam waists spaced depthwise relative to the transparent material, thereby increasing processing speed. | 02-04-2010 |
20090311513 | METHOD FOR DEPOSITING CRYSTALLINE TITANIA NANOPARTICLES AND FILMS - A one-step and room-temperature process for depositing nanoparticles or nanocomposite (nanoparticle-assembled) films of metal oxides such as crystalline titanium dioxide (TiO | 12-17-2009 |
20090268265 | ULTRASHORT LASER MICRO-TEXTURE PRINTING - Systems and methods for providing laser texturing of solid substrates are disclosed. The texturing may be used to provide grayscale images obtainable from substrates, which may include steel, aluminum, glass, and silicon. In some embodiments, images may be obtainable from the substrate by modifying the reflective, diffractive, and/or absorptive features of the substrate or the substrate surface by forming random, periodic, and/or semi-periodic micro-structure features on the substrate (or substrate surface) by an ultrafast laser pulse train. The ultrafast pulse train may be modulated in order to vary, for example, optical exposure time, pulse train intensity, laser polarization, laser wavelength, or a combination of the aforementioned. The ultrafast pulse train and the substrate may be scanned with respect to each other to provide different optical energies to different regions of the substrate (or substrate surface). In some embodiments, the image is provided by making one or more passes of the ultrafast laser pulse train relative to the substrate. | 10-29-2009 |
20090246530 | Method For Fabricating Thin Films - A method of pulsed laser deposition (PLD) capable of continuously tuning formed-film morphology from that of a nanoparticle aggregate to a smooth thin film free of particles and droplets. The materials that can be synthesized using various embodiments of the invention include, but are not limited to, metals, alloys, metal oxides, and semiconductors. In various embodiments a ‘burst’ mode of ultrashort pulsed laser ablation and deposition is provided. Tuning of the film morphology is achieved by controlling the burst-mode parameters such as the number of pulses and the time-spacing between the pulses within each burst, the burst repetition rate, and the laser fluence. The system includes an ultrashort pulsed laser, an optical system for delivering a focused onto the target surface with an appropriate energy density, and a vacuum chamber in which the target and the substrate are installed and background gases and their pressures are appropriately adjusted. | 10-01-2009 |
20090246413 | METHOD FOR FABRICATING THIN FILMS - A method of ultrashort pulsed laser deposition (PLD) capable of continuously tuning formed-film morphology from that of a nanoparticle aggregate to a smooth thin film completely free of particles and droplets. The materials that can be synthesized using various embodiments of the invention include, but are not limited to, metals, alloys, metal oxides, and semiconductors. A ‘burst’ mode of ultrashort pulsed laser ablation and deposition is provided, where each ‘burst’ contains a train of laser pulses. Tuning of the film morphology is achieved by controlling the burst-mode parameters such as the number of pulses and the time-spacing between the pulses within each burst, the burst repetition rate, and the laser fluence. The system includes an ultrashort pulsed laser, an optical setup for delivering the laser beam such that the beam is focused onto the target surface with an appropriate average energy density (fluence), and a vacuum chamber in which the target and the substrate are installed and background gases and their pressures are appropriately adjusted. | 10-01-2009 |
20090245729 | ULTRA SMALL CORE FIBER WITH DISPERSION TAILORING - Various embodiments of optical fiber designs and fabrication processes for ultra small core fibers (USCF) are disclosed. In some embodiments, the USCF includes a core that is at least partially surrounded by a region comprising first features. The USCF further includes a second region at least partially surrounding the first region. The second region includes second features. In an embodiment, the first features are smaller than the second features, and the second features have a filling fraction greater than about 90 percent. The first features and/or the second features may include air holes. Embodiments of the USCF may provide dispersion tailoring. Embodiments of the USCF may be used with nonlinear optical devices configured to provide, for example, a frequency comb or a supercontinuum. | 10-01-2009 |
20090201575 | HIGH POWER PARALLEL FIBER ARRAYS - High power parallel fiber arrays for the amplification of high peak power pulses are described. Fiber arrays based on individual fiber amplifiers as well as fiber arrays based on multi-core fibers can be implemented. The optical phase between the individual fiber amplifier elements of the fiber array is measured and controlled using a variety of phase detection and compensation techniques. High power fiber array amplifiers can be used for EUV and X-ray generation as well as pumping of parametric amplifiers. | 08-13-2009 |
20090123121 | RARE EARTH DOPED AND LARGE EFFECTIVE AREA OPTICAL FIBERS FOR FIBER LASERS AND AMPLIFIERS - Various embodiments described herein include rare earth doped glass compositions that may be used in optical fiber and rods having large core sizes. Such optical fibers and rods may be employed in fiber lasers and amplifiers. The index of refraction of the glass may be substantially uniform and may be close to that of silica in some embodiments. Possible advantages to such features include reduction of formation of additional waveguides within the core, which becomes increasingly a problem with larger core sizes. | 05-14-2009 |
20090122815 | RESONANT FABRY-PEROT SEMICONDUCTOR SATURABLE ABSORBERS AND TWO PHOTON ABSORPTION POWER LIMITERS - An intracavity resonant Fabry-Perot saturable absorber (R-FPSA) induces modelocking in a laser such as a fiber laser. An optical limiter such as a two photon absorber (TPA) can be used in conjunction with the R-FPSA, so that Q-switching is inhibited, resulting in laser output that is cw modelocked. By using both an R-FPSA and a TPA, the Q-switched modelocked behavior of a fiber laser is observed to evolve into cw modelocking. | 05-14-2009 |
20090097520 | INEXPENSIVE VARIABLE REP-RATE SOURCE FOR HIGH-ENERGY, ULTRAFAST LASERS - System for converting relatively long pulses from rep-rate variable ultrafast optical sources to shorter, high-energy pulses suitable for sources in high-energy ultrafast lasers. Fibers with positive group velocity dispersion (GVD) and self phase modulation are advantageously employed with the optical sources. These systems take advantage of the need for higher pulse energies at lower repetition rates so that such sources can be cost effective. | 04-16-2009 |
20090097515 | YB: AND ND: MODE-LOCKED OSCILLATORS AND FIBER SYSTEMS INCORPORATED IN SOLID-STATE SHORT PULSE LASER SYSTEMS - The invention describes classes of robust fiber laser systems usable as pulse sources for Nd: or Yb: based regenerative amplifiers intended for industrial settings. The invention modifies adapts and incorporates several recent advances in FCPA systems to use as the input source for this new class of regenerative amplifier. | 04-16-2009 |
20090097514 | FEMTOSECOND LASER PROCESSING SYSTEM WITH PROCESS PARAMETERS, CONTROLS AND FEEDBACK - A femtosecond laser based laser processing system having a femtosecond laser, frequency conversion optics, beam manipulation optics, target motion control, processing chamber, diagnostic systems and system control modules. The femtosecond laser based laser processing system allows for the utilization of the unique heat control in micromachining, and the system has greater output beam stability, continuously variable repetition rate and unique temporal beam shaping capabilities. | 04-16-2009 |
20090095023 | ULTRA HIGH NUMERICAL APERTURE OPTICAL FIBERS - Various embodiments described include optical fiber designs and fabrication processes for ultra high numerical aperture optical fibers (UHNAF) having a numerical aperture (NA) of about 1. Various embodiments of UHNAF may have an NA greater than about 0.7, greater than about 0.8, greater than about 0.9, or greater than about 0.95. Embodiments of UHNAF may have a small core diameter and may have low transmission loss. Embodiments of UHNAF having a sufficiently small core diameter provide single mode operation. Some embodiments have a low V number, for example, less than 2.4 and large dispersion. Some embodiments of UHNAF have extremely large negative dispersion, for example, less than about −300 ps/nm/km in some embodiments. Systems and apparatus using UHNAF are also disclosed. | 04-16-2009 |
20080292808 | METHOD OF PRODUCING COMPOUND NANORODS AND THIN FILMS - A method of producing compound nanorods and thin films under a controlled growth mode is described. The method involves ablating compound targets using an ultrafast pulsed laser and depositing the ablated materials onto a substrate. When producing compound nanorods, external catalysts such as pre-deposited metal nanoparticles are not involved. Instead, at the beginning of deposition, simply by varying the fluence at the focal spot on the target, a self-formed seed layer can be introduced for nanorods growth. This provides a simple method of producing high purity nanorods and controlling the growth mode. Three growth modes are covered by the present invention, including nanorod growth, thin film growth, and nano-porous film growth. | 11-27-2008 |
20080251720 | BEAM SCANNING IMAGING METHOD AND APPARATUS - An imaging apparatus uses focusing and collecting optics in combination with steering optics for efficient and speedy imaging of a target using an extended terahertz electro-magnetic range challenged by weak sources and low sensitivity of detection. This invention addresses efficient detection of this wave in combination with a speedy imaging speed. By proper location of optics to utilize angular conversion of the beam to a lateral scan, a rastering imaging apparatus is demonstrated without moving target or entire imaging system. A mirror-lens set is used to steer the terahertz (THz) beam along and (or) to collect the THz beam from each point of the target. The target is imaged with a much higher speed than when moving the target or the entire imaging system. A THz wave image can be taken at video frequency for practical usage of the apparatus in diverse application areas, where it has not been considered to be feasible. | 10-16-2008 |
20080240663 | ULTRA HIGH NUMERICAL APERTURE OPTICAL FIBERS - Various embodiments described include optical fiber designs and fabrication processes for ultra high numerical aperture optical fibers (UHNAF) having a numerical aperture (NA) of about 1. Various embodiments of UHNAF may have an NA greater than about 0.7, greater than about 0.8, greater than about 0.9, or greater than about 0.95. Embodiments of UHNAF may have a small core diameter and may have low transmission loss. Embodiments of UHNAF having a sufficiently small core diameter provide single mode operation. Some embodiments have a low V number, for example, less than 2.4 and large dispersion. Some embodiments of UHNAF have extremely large negative dispersion, for example, less than about −300 ps/nm/km in some embodiments. Systems and apparatus using UHNAF are also disclosed. | 10-02-2008 |