| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 359341400 | Feedback | 17 |
| 20100245988 | OPTICAL AMPLIFIER - An optical amplifier includes a first excitation light source that outputs a first excitation light; a second excitation light source that outputs a second excitation light; a first amplifying optical fiber doped with a rare-earth element and excited by the first excitation light to amplify light input to the first amplifying optical fiber; and a second amplifying optical fiber doped with a rare-earth element and excited by the second excitation light to amplify the light from the first amplifying optical fiber. A ratio between the intensity of the first excitation light and the intensity of the second excitation light is controlled according to the number of signal lights wavelength-multiplexed in the light input. | 09-30-2010 |
| 20110032604 | PASSIVE ALL-FIBER INTEGRATED HIGH POWER COHERENT BEAM COMBINATION - A fiber laser amplifier system including a beam splitter that splits a feedback beam into a plurality of fiber beams where a separate fiber beam is sent to a fiber amplifier for amplifying the fiber beam. A tapered fiber bundle couples all of the output ends of all of the fiber amplifiers into a combined fiber providing a combined output beam. An end cap is optically coupled to an output end of the tapered fiber bundle to expand the output beam. A beam sampler samples a portion of the output beam from the end cap and provides a sample beam. A single mode fiber receives the sample beam from the beam sampler and provides the feedback beam. | 02-10-2011 |
| 20130148191 | FIBER AMPLIFIER SYSTEM INCLUDING TAPERED FIBER BUNDLE AND POLARIZATION CONTROL - A fiber laser amplifier system including a beam splitter that splits a feedback beam into a plurality of fiber beams where a separate fiber beam is sent to a fiber amplifier for amplifying the fiber beam. A tapered fiber bundle couples all of the output ends of all of the fiber amplifiers into a combined fiber providing a combined output beam. A beam sampler samples a portion of the output beam from the tapered fiber bundle and provides a sample beam. A single mode fiber receives the sample beam from the beam sampler and provides the feedback beam. | 06-13-2013 |
| 20150109661 | REFLECTOR BASED ON A DIRECTIONALLY COUPLED OPTICAL LOOP - An optical device includes an optical reflector based on a coupled-loopback optical waveguide. In particular, an input port, an output port and an optical loop in arms of the optical reflector are optically coupled to a directional coupler. The directional coupler evanescently couples an optical signal between the arms. For example, the directional coupler may include: a multimode interference coupler and/or a Mach-Zehnder Interferometer (MZI). Moreover, destructive interference during the evanescent coupling determines the reflection and transmission power coefficients of the optical reflector. | 04-23-2015 |
| 20160104995 | SYSTEM AND METHOD FOR A DELIVERY FIBER FOR ISOLATION AGAINST BACK REFLECTIONS - An apparatus and method that provide optical isolation by permitting substantially all forward-propagating light into a delivery fiber from an optical amplifier and substantially preventing backward-traveling light from the delivery fiber entering the optical amplifier without the use of a conventional optical isolator. Eliminating the isolator improves efficiency and reduces cost. Some embodiments use a delivery fiber having a non-circular core in order to spread a single-mode signal into multiple modes such that any backward-propagating reflection is inhibited from reentering the single-mode amplifier. Some embodiments amplify an optical signal in a gain fiber having an output end, output the forward-propagating amplified signal as a high-brightness optical beam (having a first Rayleigh range) into a removable delivery fiber having a non-circular waveguide, output the amplified signal from a distal end of the delivery fiber, and, without the use of a non-linear optical isolator, inhibit backward-propagating light from re-entering the gain fiber. | 04-14-2016 |
| 359341410 | Automatic Gain Control (AGC) | 10 |
| 20080212167 | CASCADED OPTICAL AMPLIFIER AND CONTROL METHOD THEREOF - A cascaded optical amplifier including a first optical amplifier and a second optical amplifier in cascaded arrangement is provided. Each of the first optical amplifier and the second optical amplifier has a respective input for receiving an optical signal, an output for outputting an amplified optical signal, and a control input for controlling the gain of the optical amplifier. The cascaded optical amplifier includes a sensor for sensing upstream of the input of the second optical amplier a signal relating to operation of the cascaded optical amplifier. In addition, the cascaded optical amplifier includes a controller for providing control signals to the respective control inputs of the first amplifier and the second amplifier, the controller providing the control signal to the second optical amplifier as a function of the sensed signal. | 09-04-2008 |
| 20090059354 | OPTICAL AMPLIFIER TRANSIENT CONTROL WITH GAIN ERROR LIMITS - Optical amplifier transient control methods and apparatus which limit the extent of cumulative transient gain errors in the rapid control of multiple optical amplifiers in a communication system. In an exemplary embodiment, if the input power to an optical amplifier drops below a predetermined threshold, the gain of the amplifier is set to clamp the output power of the amplifier to its initial level less the threshold, thereby preventing the continuous growth of gain error. This is based on the assumption that once the input power goes below the threshold, it should no longer go above the threshold until the transient condition is corrected. The present invention can operate to handle down- as well as up-transient events and is not amplifier technology dependent. | 03-05-2009 |
| 20100079856 | Optical transmission system - In an optical transmission system, a controller acquires a noise light loss value, which indicates a loss that noise light output from an upstream-side optical amplifier undergoes during propagation to a downstream-side optical amplifier through an optical loss medium, and a signal beam loss value, which indicates a loss that a signal beam output from the upstream-side optical amplifier undergoes during propagation to the downstream-side optical amplifier through the optical loss medium, obtains, as a loss difference, a difference between the noise light loss value and the signal beam loss value and, when setting up the downstream-side optical amplifier, determines the gain of the downstream-side optical amplifier by compensating the loss difference. | 04-01-2010 |
| 20110286085 | OPTICAL AMPLIFIER - An optical amplifier includes an input port, an output port, an amplification medium, a light source, a monitor, and a controller. The amplification medium with which doped an rare-earth element for optical amplification is allocated on an optical path between the input port and the output port. The light source supplies the amplification medium with an excitation light. The monitor monitors a total power of an optical signal of each wavelength according to a monitor period which is longer than a transient response time of the amplification medium. The controller controls the light source so that a power of the excitation light is constant when a monitor value of the monitor is equal to or smaller than a predetermined threshold value and controls the light source so that an optical gain in the amplification medium is constant when the monitor value is larger than the predetermined threshold value. | 11-24-2011 |
| 20120099186 | Optical Amplification Device and Method - It is described an optical amplification device for receiving an optical input signal and transmitting an amplified optical output signal on the basis of the optical input signal comprising an optical amplifier that comprises an input and an output. An optical gain control unit is connected to the output path of the optical amplifier and the optical gain control unit is connected to the input path of the optical amplifier. The optical gain control unit is configured to control the gain of the optical output signal. Additionally, an electrical gain control unit is connected to the output path of the optical amplifier. The electrical gain control unit is also connected to the input path of the optical amplifier. The electrical gain control unit is configured to control the gain of the optical output signal. | 04-26-2012 |
| 20120154904 | METHOD AND APPARATUS FOR GAIN TILT COMPENSATION OVER FIBER OPTIC CABLE - An embodiment of the invention comprises determining a gain tilt based on power measurements from a power measurement block, determining a noise figure penalty based on the gain tilt, determining a gain tilt compensation to compensate for the gain tilt taking into account the noise figure penalty, and communicating the gain tilt compensation to an amplifier block to apply the gain tilt compensation to subsequently received wavelengths. | 06-21-2012 |
| 20130148192 | DIFFERENTIATION OF POWER AND CHANNEL COUNT CHANGES IN OPTICALLY AMPLIFIED LINKS - Exemplary embodiments of the invention are drawn to a method and apparatus for the differentiation of power and channel count changes in optically amplified links. Additionally, configuration of a corresponding optical amplifier can be based on the determination of the power and channel count changes. | 06-13-2013 |
| 20140043675 | CONTROLLER WHICH CONTROLS A VARIABLE OPTICAL ATTENUATOR TO CONTROL THE POWER LEVEL OF A WAVELENGTH-MULTIPLEXED OPTICAL SIGNAL WHEN THE NUMBER OF CHANNELS ARE VARIED - An optical amplifier which amplifies a wavelength division multiplexed optical signal having a variable number of channels associated with different wavelengths and outputs the amplified WDM optical signal. The optical amplifier includes a first optical amplifier which amplifies the wavelength division multiplexed optical signal and outputs the first optical amplifier amplified wavelength division multiplexed optical signal; a variable optical attenuator which controls a level of the first optical amplifier amplified wavelength division multiplexed optical signal and outputs the controlled wavelength division multiplexed optical signal; a second optical amplifier which amplifies the controlled wavelength division multiplexed optical signal and outputs the amplified, controlled wavelength division multiplexed optical signal; and a controller which controls the wavelength division multiplexed optical signal to be amplified with a constant gain. | 02-13-2014 |
| 20140253998 | OPTICAL AMPLIFIER AND METHOD OF CONTROLLING OPTICAL AMPLIFIER - An optical amplifier comprising: a pumping light source supplying a pumping light to an optical fiber as an amplification medium; an ASE light power detector detecting an ASE light power including an external ASE power flowing from an upstream side outside an amplification signal band; and a control unit setting a gain within the amplification signal band by using the ASE light power detected by the ASE light power detector outside the amplification signal band. The control unit controls the pumping light source by compensating for an influence of the external ASE power, obtained by measuring a relationship between the gain within the amplification signal band and the ASE light power outside the amplification signal band, to set initially the gain within the amplification signal band. | 09-11-2014 |
| 20220140913 | Optical Receiver Evaluation Method and Optical Receiver Evaluation Apparatus - There are provided an evaluation method and an evaluation device for an optical receiver capable of evaluating only a phase error between optical 90-degree hybrids with high accuracy even when there is a skew between channels in the optical receiver. In the evaluation method and the evaluation device for the optical receiver including optical 90-degree hybrids, a phase error between the optical 90-degree hybrids is calculated by calculation of decomposing a transfer function of the optical receiver into a product of matrixes to evaluate the optical receiver. | 05-05-2022 |
| 359341430 | Surge protection | 1 |
| 20100245989 | Multi-Stage Erbium-Doped Fiber Amplifier With a Single Programmable Logic Device Control Circuit And Method of Controlling Thereof - A control circuit for a fiber amplifier having a first stage pump and at least one second stage pump and method of controlling thereof is disclosed. The control circuit includes a control gate controlling a current through the first stage pump. A sensor for detecting a voltage across the first stage pump and providing a measured output of the voltage is provided. The control circuit further includes a control loop configured for selectively controlling the current through the control gate in accordance with the measured output and a set reference point is also provided. | 09-30-2010 |
| 359341440 | Fault detection | 1 |
| 20130148193 | FIBER AMPLIFIER SYSTEM INCLUDING TAPERED FIBER BUNDLE AND COMBINED LENS AND SAMPLING GRATING - A fiber laser amplifier system including a beam splitter that splits a feedback beam into a plurality of fiber beams where a separate fiber beam is sent to a fiber amplifier for amplifying the fiber beam. A tapered fiber bundle couples the output ends of all of the fiber amplifiers into a combined fiber providing a combined output beam. A beam sampler samples a portion of the output beam from the tapered fiber bundle and provides a sample beam. A single mode fiber receives the sample beam from the beam sampler and provides the feedback beam. | 06-13-2013 |
