Patent application number | Description | Published |
20080198888 | Semiconductor laser apparatus and optical amplifier apparatus - A method of bonding a compound semiconductor on a silicon waveguide is used for attaining a laser above a silicon substrate. While it is essential to attain laser oscillation by injection of a current, since amorphous is formed at the bonding surface of a silicon compound semiconductor, it is difficult to directly inject the current through the silicon waveguide to the compound semiconductor. Further, even when an electrode is formed near the waveguide and the current is injected, since the current is not injected near the silicon waveguide, laser oscillation through the silicon waveguide can not be attained. The problem is solved by forming a structure of laterally injecting a current to the silicon waveguide and concentrating the current near the silicon waveguide in a compound semiconductor. Specific methods includes the following two methods, that is, a method of forming a tunneling junction structure in the compound semiconductor and another method of laterally forming a P-I-N junction to the compound semiconductor. | 08-21-2008 |
20080266638 | SEMICONDUCTOR LASER AND OPTICAL MODULE - In a horizontal cavity surface emitted laser, there is provided a device structure that is capable of obtaining a circular narrow-divergence emitted beam that is high in the optical coupling efficiency with a fiber. As a first means, there is provided a horizontal cavity surface emitting laser having a structure in which the plane mirror that is inclined by 45° and the bottom lens of the oval configuration are integrally structured. As a second means, there is provided a horizontal cavity surface emitting laser in which the mirror having the columnar front surface configuration inclined by 45° and the bottom lens of the columnar front surface configuration are integrally structured. Since the horizontal component and the vertical component of the laser beam can be shaped, independently, through the above means. As a result, it is possible to obtain the circular narrow-divergence emitted beam. | 10-30-2008 |
20080291957 | WAVELENGTH TUNABLE LASER APPARATUS AND WAVELENGTH CONTROL METHOD - Included are: a gain chip having a gain unit and a phase control region; a current supply for causing a positive current to flow to the phase control region; a voltage supply for applying a bias voltage to the phase control region; and a control unit for selectively driving the current supply or the voltage supply depending on a direction of the wavelength shift. The control unit drives the current supply when a laser wavelength is to be shifted to a shorter wavelength side from a wavelength with the current supply and the voltage supply being turned off, and drives the voltage supply when the laser wavelength is to be shifted to a longer wavelength side from a wavelength with the current supply and the voltage supply being turned off. | 11-27-2008 |
20090090925 | SEMICONDUCTOR DEVICE - There are a silicon laser device having a IV-group semiconductor such as silicon or germanium equivalent to the silicon as a basic constituent element on a substrate made of the silicon, and the like by a method capable of easily forming the silicon laser device by using a general silicon process, and a manufacturing method thereof. The silicon laser device is an ultrathin silicon laser that includes a first electrode unit injecting electrons, a second electrode unit injecting holes, a light emitting unit electrically connected to the first electrode unit and the second electrode unit, wherein the light emitting unit is made of single-crystal silicon and has a first surface (top surface) and a second surface (bottom surface) opposed to the first surface, a waveguide made of a first dielectric, which is disposed in the vicinity of the light emitting unit, by setting surface directions of the first and second surfaces as a surface (100) and thinning a thickness of the light emitting unit in a direction perpendicular to the first and second surfaces, and a mirror formed by alternately adjoining the first dielectric and a second dielectric. | 04-09-2009 |
20090262762 | Laser Device and Controlling Method Therefor - A laser device capable of preventing deterioration of a light signal and a controlling method therefor are provided. A wavelength tunable laser module provided with a resonator including the wavelength tunable filter and a semiconductor light amplifier having a phase adjustment region and a light amplifying region, in which a wavelength margin between a peak transmission wavelength of a wavelength tunable filter and a mode hop occurring wavelength on a short wave side is smaller than that on a long wave side includes: a wavelength tunable laser module controller including an optical output sampling portion for detecting light intensity of light emitted from the resonator, a dither signal source for generating a dither signal for varying a phase adjustment signal to be applied to the phase adjustment region so that the detected light intensity becomes the maximum, and an FM signal source for generating an FM signal for oscillating the phase adjustment signal to be applied to the phase adjustment region with a period shorter than a variation period of the dither signal. The optical output sampling portion detects the light intensity in synchronization with oscillation of the phase adjustment signal by the FM signal. | 10-22-2009 |
20090263078 | Optical device - Plural p-n junctions are formed in a waveguide such that they have junction interfaces in a normal direction to a surface of a substrate (to an extending direction of the substrate). Accordingly, a doping concentration changes in only a horizontal direction in the substrate, and it is possible to fabricate using the same processes as those for silicon electronic devices and to perform device fabricating at a low cost. Moreover, two or more junction interfaces are formed in the waveguide and thus an occupied area of the waveguide in a refractive index modulation region expands. Therefore, the efficiency of the refractive index modulation can be improved and a low-voltage operation is possible. | 10-22-2009 |
20090268772 | Semiconductor laser apparatus - A wavelength variable laser smaller in size than the conventional one can be achieved by arranging a gain chip, an etalon filter and a fifth reflective mirror on an AlN submount and longitudinally integrating the gain chip in which a 45° mirror and a lens are integrated and the etalon filter. A laser cavity has a structure in which light passes through an active layer from a first reflective mirror realized by an end surface of the gain chip, is reflected by the 45° mirror at an angle of 90° and then passes through the lens. The light having passed through the lens is converted into parallel light, passes through the etalon filter and reaches the fifth reflective mirror and is then reflected. The reflected light returns through the same optical path and reaches the first reflective mirror realized by the end surface of the gain chip. | 10-29-2009 |
20100142568 | WAVELENGTH TUNABLE FILTER AND WAVELENGTH TUNABLE LASER MODULE - Disclosed are a wavelength tunable filter and a wavelength tunable laser module that are of a codirectional coupler type whose characteristics do not significantly vary with a process error. They are structured so as to include a semiconductor substrate which has a first optical waveguide and a second optical waveguide. The first and the second optical waveguide are extended from a first side of the semiconductor substrate to an opposing second side thereof. The first optical waveguide includes a first core layer, which has a planar layout having periodic convexes and concaves, and a pair of electrodes, which vertically sandwich the first core layer. The second optical waveguide includes a second core layer, which has a lower refractive index than the first core layer. Further, a layer having the same composition and film thickness as the second core layer is placed under the first core layer. | 06-10-2010 |
20100142885 | OPTICAL MODULE - The first and second optical waveguide device portions are optically coupled by 45-degree total reflection mirrors integrally formed in the respective device portions. The light generated by the first optical waveguide device portion is bent upward by the total reflection mirror of the first optical waveguide device portion. The light is totally reflected by the 45-degree total reflection mirror of the second optical waveguide device portion, and coupled to the second optical waveguide device portion. The first optical waveguide device portion has a lens device for focusing the emitted light onto a light emitting portion. The second optical waveguide device portion has a lens device for focusing the incident light onto a light receiving portion. | 06-10-2010 |
20130322478 | Semiconductor Laser Device - Beams of light having wavelengths different from each other are generated in a plurality of light generation portions, the beams of light each generated in the plurality of light generation portions are reflected by a monolithic integrated mirror and are incident to a condenser lens, and emission positions on the condenser lens of the beams of light each generated in the plurality of light generation portions deviate from a central position of the condenser lens by a predetermined amount. | 12-05-2013 |