Abstract: An object of the present invention is to provide a temperature-independent optical frequency shifter for generating sub-carriers with a miniaturizable configuration, as well as to provide an all-optical OFDM modulator using the same that is compact, has low temperature dependence, and is even compatible with different frequency grids. Provided is an optical frequency shifter and an optical modulator using the same, the optical frequency shifter comprises one input optical port, a 1-input, 2-output optical coupler optically connected thereto, two Mach-Zehnder modulation units individually optically connected to the two outputs thereof, a 2-input, 2-output optical coupler optically connected to the individual outputs thereof, and two output optical ports optically connected to the outputs thereof, wherein the two Mach-Zehnder modulation units are driven by periodic waveforms at the same frequency whose phases differ from each other by (2p+1)?/2 (p: integer).

Abstract: In an optical component configured to fix to a mount an optical device chip in which waveguide type optical devices having different thermal expansion coefficients are butt-jointed, deterioration in reliability due to thermal stress is suppressed. The optical component (300) comprises an optical device chip (310) including an LN waveguide (311), a first PLC waveguide (312), a second PLC waveguide (313), and a fiber alignment member (314), a mount (320), and optical fibers (330). Each of connection faces between the first PLC waveguide and the fiber alignment member is configured as an tilted structure, and each of connection faces between the LN waveguide, and the first and second PLC waveguides is configured as a right-angled structure. In the right-angled structure, the connection faces are connected by an adhesive having a lower Young's modulus than that of an adhesive used on the connection faces of the tilted structure.

Abstract: An object of the present invention is to provide a temperature-independent optical frequency shifter for generating sub-carriers with a miniaturizable configuration, as well as to provide an all-optical OFDM modulator using the same that is compact, has low temperature dependence, and is even compatible with different frequency grids. Provided is an optical frequency shifter and an optical modulator using the same, the optical frequency shifter comprises one input optical port, a 1-input, 2-output optical coupler optically connected thereto, two Mach-Zehnder modulation units individually optically connected to the two outputs thereof, a 2-input, 2-output optical coupler optically connected to the individual outputs thereof, and two output optical ports optically connected to the outputs thereof, wherein the two Mach-Zehnder modulation units are driven by periodic waveforms at the same frequency whose phases differ from each other by (2p+1) ?/2 (p: integer).

Abstract: In an optical component configured to fix to a mount an optical device chip in which a plurality of waveguide type optical devices having different thermal expansion coefficients are butt-jointed, deterioration in reliability due to thermal stress is suppressed. The optical component (300) comprises an optical device chip (310) including an LN waveguide (311), a first PLC waveguide (312) connected to an end of the LN waveguide (311), a second PLC waveguide (313) connected to the other end of the LN waveguide (311), and a fiber alignment member (314) connected to the first PLC waveguide (312), a mount (320) on which the optical device chip (310) is mounted, and optical fibers (330) aligned to the fiber alignment member (314).

Abstract: A semiconductor optical modulator that includes a first semiconductor optical waveguide having a laminated structure including a core layer, a first clad layer, a second clad layer, and a barrier layer, the first clad layer and the second clad layer being disposed below and above the core layer, the barrier layer being inserted between the second clad layer and the core layer; a second semiconductor optical waveguide having a laminated structure in which the second clad layer has a p-type semiconductor penetrating locally through a n-type semiconductor in a laminated direction in the laminated structure of the first semiconductor optical waveguide; a first electrode connected to the first clad layer of the first semiconductor optical waveguide; and a second electrode electrically connecting the second clad layer of the first semiconductor optical waveguide and the p-type semiconductor of the second clad layer of the second semiconductor optical waveguide.

Abstract: In an optical component, a part of a waveguide type optical device is fixed to a convex portion of a mount. The optical component includes an optical support base, a pressure member and a pressure support base. The optical device support base is interposed between the mount and the presser member enough to be slidable in a direction parallel to surfaces of the mount and the presser member.

Abstract: In a nest MZI modulator in which each arm includes a child MZI, the power consumption is reduced. The hybrid integrated-type nest MZI modulator of the embodiment 1a is configured so that, instead of placing a relative phase adjusting section in a parent MZI, a bias electrode Bias 90° in which an electric field is applied in the same direction to the polarization direction in both of the upper and lower arms is placed in each child MZI (see FIG. 4B). The bias electrode Bias 90° provided in each child MZI constitute the entirety of a relative phase adjusting section. The optical signals are subjected to a phase change after the output from the child MZI (see FIG. 1A), because such relative phase adjusting section can subject the optical signals of the upper and lower arms of the child MZI to a shift change in the same direction, respectively.

Abstract: An optical semiconductor module in which displacement resulting from fixation of lenses is effectively corrected includes a first lens (102), a second lens (103), and a third lens (104) arranged between a semiconductor laser (101) and a semiconductor optical modulator (105). The first lens (102) and the second lens (103) form a collimate lens optical system. The first lens (102) converts light emitted by the semiconductor laser (101) into parallel light rays. The second lens (103) focuses the parallel light rays on the semiconductor optical modulator (105) to couple the light rays to the semiconductor optical modulator (105). The third lens (104) has a longer focal distance than the first and second lenses. Thus, displacement of the lenses resulting from fixation thereof can be corrected by adjusting in position and fixing the first and second lenses (102, 103) and then adjusting in position and fixing the third lens.

Abstract: The present invention can provide an npin-type optical modulator that has a high withstand voltage and is easily fabricated. A semiconductor optical amplifier (10) according to an embodiment of the present invention is an npin-type semiconductor optical modulator in which layers are sequentially stacked, with a cathode layer (12-1) arranged on the substrate side, including at least a first n-type cladding layer (13-1), a p-type cladding layer (14), a core layer (17) and a second n-type cladding layer (13-2). In this semiconductor optical modulator, the p-type cladding layer (14) is electrically connected to an electrode (18-1) of the cathode layer. Accordingly, the accumulation of holes in the p-type cladding layer associated with light absorption in the npin-type optical modulator can be absorbed in the electrode on the negative side.

Abstract: The present invention can provide an npin-type optical modulator that has a high withstand voltage and is easily fabricated. A semiconductor optical amplifier (10) according to an embodiment of the present invention is an npin-type semiconductor optical modulator in which layers are sequentially stacked, with a cathode layer (12-1) arranged on the substrate side, including at least a first n-type cladding layer (13-1), a p-type cladding layer (14), a core layer (17) and a second n-type cladding layer (13-2). In this semiconductor optical modulator, the p-type cladding layer (14) is electrically connected to an electrode (18-1) of the cathode layer. Accordingly, the accumulation of holes in the p-type cladding layer associated with light absorption in the npin-type optical modulator can be absorbed in the electrode on the negative side.

Abstract: A semiconductor optical modulator that includes a first semiconductor optical waveguide having a laminated structure including a core layer, a first clad layer, a second clad layer, and a barrier layer, the first clad layer and the second clad layer being disposed below and above the core layer, the barrier layer being inserted between the second clad layer and the core layer; a second semiconductor optical waveguide having a laminated structure in which the second clad layer has a p-type semiconductor penetrating locally through a n-type semiconductor in a laminated direction in the laminated structure of the first semiconductor optical waveguide; a first electrode connected to the first clad layer of the first semiconductor optical waveguide; and a second electrode electrically connecting the second clad layer of the first semiconductor optical waveguide and the p-type semiconductor of the second clad layer of the second semiconductor optical waveguide.

Abstract: A water-based coated-type vibration damping material uses a styrene-butadiene copolymer emulsion as a resin emulsion and a calcium carbonate as an inorganic filler. The water-based coated-type vibration damping material limits a blending amount of a glycol to 2% by weight or less. In case of making a coated layer by such water-based coated-type vibration damping material, there is no blister generation observed after a hot water immersion of 168 hours (7 days), after a hot water immersion of 336 hours (14 days) and after a hot water immersion of 1000 hours, either.

Abstract: The present invention relates to a semiconductor optoelectronic waveguide having a nin-type hetero structure which is able to stably operate an optical modulator. On the upper and lower surfaces of the core layer determined for the structure so that electro-optical effects are effectively exerted at an operating light wavelength and are provided with intermediate clad layers having a band gap which is greater than that of the core layer 11. Respectively on the upper and the lower surface of the intermediate clad layer are provided the clad layers having the band gap which is greater than those of the intermediate clad layers. On the upper surface of the clad layer are sequentially laminated a p-type layer and an n-type layer. In the applied voltage range used under an operating state, a whole region of the p-type layer and a part or a whole region of the n-type layer are depleted.

Abstract: There is provided a semiconductor optical modulator capable of performing a stable operation and having an excellent voltage-current characteristic to an electric field while exhibiting the characteristic of a semiconductor optical modulator with an n-i-n structure. The semiconductor optical modulator includes a waveguide structure that is formed by sequentially growing an n-type InP clad layer (11), a semiconductor core layer (13) having an electro-optic effect, a p-InAlAs layer (15), and an n-type InP clad layer (16). An electron affinity of the p-InAlAs layer (15) is smaller than an electron affinity of the n-type InP clad layer (16). In the waveguide structure having such a configuration, a non-dope InP clad layer (12) and a non-dope InP clad layer (14) may be respectively provided between the n-type InP clad layer (11) and the semiconductor core layer (13), and between the semiconductor core layer (13) and the p-InAlAs layer (15).

Abstract: The present invention relates to a semiconductor optoelectronic waveguide having a nin-type hetero structure which is able to stably operate an optical modulator. On the upper and lower surfaces of the core layer determined for the structure so that electro-optical effects are effectively exerted at an operating light wavelength and are provided with intermediate clad layers having a band gap which is greater than that of the core layer 11. Respectively on the upper and the lower surface of the intermediate clad layer are provided the clad layers having the band gap which is greater than those of the intermediate clad layers. On the upper surface of the clad layer are sequentially laminated a p-type layer and an n-type layer. In the applied voltage range used under an operating state, a whole region of the p-type layer and a part or a whole region of the n-type layer are depleted.

Abstract: There is provided a semiconductor optical modulator capable of performing a stable operation and having an excellent voltage-current characteristic to an electric field while exhibiting the characteristic of a semiconductor optical modulator with an n-i-n structure. The semiconductor optical modulator includes a waveguide structure that is formed by sequentially growing an n-type InP clad layer (11), a semiconductor core layer (13) having an electro-optic effect, a p-InAlAs layer (15), and an n-type InP clad layer (16). An electron affinity of the p-InAlAs layer (15) is smaller than an electron affinity of the n-type InP clad layer (16). In the waveguide structure having such a configuration, a non-dope InP clad layer (12) and a non-dope InP clad layer (14) may be respectively provided between the n-type InP clad layer (11) and the semiconductor core layer (13), and between the semiconductor core layer (13) and the p-InAlAs layer (15).

Abstract: The present invention relates to a semiconductor optoelectronic waveguide having a nin-type hetero structure which is able to stably operate an optical modulator. On the upper and lower surfaces of the core layer determined for the structure so that electro-optical effects are effectively exerted at an operating light wavelength and are provided with intermediate clad layers having a band gap which is greater than that of the core layer 11. Respectively on the upper and the lower surface of the intermediate clad layer are provided the clad layers having the band gap which is greater than those of the intermediate clad layers. On the upper surface of the clad layer are sequentially laminated a p-type layer and an n-type layer. In the applied voltage range used under an operating state, a whole region of the p-type layer and a part or a whole region of the n-type layer are depleted.

Abstract: A semiconductor optical converter for use principally in an optical communications system or an optical information processing system. The semiconductor optical converter comprises an n-InP clad layer (12), an optical waveguide layer (13), an SI-InP clad layer (14), and an n-InP clad layer (15) formed sequentially on an SI-InP substrate (11), characterized in that a voltage is applied from an electrode (16) connected with the n-InP clad layer (15) and a ground electrode (17) connected with the n-InP clad layer (12). The semiconductor optical converter is especially applicable as a semiconductor phase modulator or a semiconductor Mach-Zehnder phase modulator operating at low voltages and having a low waveguide loss.

Abstract: The present invention relates to a semiconductor optoelectronic waveguide having a nin-type hetero structure which is able to stably operate an optical modulator. On the upper and lower surfaces of the core layer determined for the structure so that electro-optical effects are effectively exerted at an operating light wavelength and are provided with intermediate clad layers having a band gap which is greater than that of the core layer 11. Respectively on the upper and the lower surface of the intermediate clad layer are provided the clad layers having the band gap which is greater than those of the intermediate clad layers. On the upper surface of the clad layer are sequentially laminated a p-type layer and an n-type layer. In the applied voltage range used under an operating state, a whole region of the p-type layer and a part or a whole region of the n-type layer are depleted.

Abstract: A water-based coated-type vibration damping material uses a styrene-butadiene copolymer emulsion as a resin emulsion and a calcium carbonate as an inorganic filler. The water-based coated-type vibration damping material limits a blending amount of a glycol to 2% by weight or less. In case of making a coated layer by such water-based coated-type vibration damping material, there is no blister generation observed after a hot water immersion of 168 hours (7 days), after a hot water immersion of 336 hours (14 days) and after a hot water immersion of 1000 hours, either.