Oclaro Japan, Inc.

Hitachi, Ltd.

Opnext Japan, Inc.

Lumentum Japan, Inc.

Nec Corporation

Other

Kouji Nakahara

Koichiro Adachi

Kazunori Shinoda

Tomonobu Tsuchiya

Shigehisa Tanaka

Takeshi Kitatani

Etsuko Nomoto

Shigetaka Hamada

Yuki Wakayama

Tetsuichirou Yamamoto

Yasushi Sakuma

Hiroya Ooki

Kazuki Suga

Atsushi Nakamura

Akira Nakanishi

Hitoshi Nakamura

Toshiki Sugawara

Masataka Shirai

Ryoji Takeyari

Shinji Tsuji

Hiroaki Inoue

Akihisa Terano

Tetsuichiro Yamamoto

Ryu Washino

Takeshi Kikawa

Akira Taike

Kaoru Okamoto

Makoto Shimaoka

Takashi Shiota

Makoto Kudo

Ryosuke Nakajima

Shoko Yokokawa

Tsurugi Sudo

An optical semiconductor device includes a multi-quantum well layer including well layers and barrier layers alternately overlapping with each other, an optical confinement layer, and a guide layer interposed between the multi-quantum well layer and the optical confinement layer. Each barrier layer is an undoped layer and an outermost layer is one of the barrier layers. The optical confinement layer has a refractive index that is greater than that of the outermost layer and a band gap that is smaller than that of the outermost layer. The guide layer includes a first adjacent layer in contact with the outermost layer and the guide layer is thinner than the optical confinement layer. Each of the optical confinement layer and the guide layer is an n-type semiconductor layer. The first adjacent layer of the guide layer has a band gap that is larger than that of the optical confinement layer.

Optical semiconductor device

An optical semiconductor device includes a substrate, a semiconductor multilayer which is formed on the substrate, and includes an optical functional layer, an insulating film formed on the semiconductor multilayer, and an electrode formed on a part of the insulating film. The insulating film covers the semiconductor multilayer except for a region in which the semiconductor multilayer and the electrode are electrically connected to each other. At least a part of a region of the insulating film that is overlapped with the electrode is thinner than a region of the insulating film that is not overlapped with the electrode.

A semiconductor optical device may include a semiconductor substrate; a mesa stripe structure that extends in a stripe shape in a first direction on the semiconductor substrate and includes a contact layer on a top layer; an adjacent layer on the semiconductor substrate and adjacent to the mesa stripe structure in a second direction orthogonal to the first direction; a passivation film that covers at least a part of the adjacent layer; a resin layer on the passivation film; an electrode that is electrically connected to the contact layer and extends continuously from the contact layer to the resin layer; and an inorganic insulating film that extends continuously from the resin layer to the passivation film under the electrode, is spaced apart from the mesa stripe structure, and is completely interposed between the electrode and the resin layer.

Semiconductor optical device

A semiconductor optical element is configured to emit or absorb light and includes a lower structure that includes a multiple quantum well layer; an upper mesa structure that is disposed on the lower structure; a current injection structure that is disposed on the upper mesa structure, when seen from an optical axis of the emitted or absorbed light, a width of a portion of the current injection structure in contact with the upper mesa structure is smaller than a width of the upper mesa structure, the portion of the current injection structure in contact with the upper mesa structure consisting of InP, and an average refractive index of the upper mesa structure is higher than a refractive index of the InP forming the current injection structure; and an insulating film covering both side surfaces of the upper mesa structure and a part of an upper surface of the upper mesa structure.

Semiconductor optical element and semiconductor optical device comprising the same

Provided is an optical semiconductor device which has long-term reliability since a threshold current is small, and a relaxation oscillation frequency is high. An optical semiconductor device includes an InP semiconductor substrate, a lower mesa structure that is disposed above the InP semiconductor substrate, and includes a multiple quantum well layer, an upper mesa structure that is disposed on the lower mesa structure, and includes a cladding layer, a buried semiconductor layer that buries both side surfaces of the lower mesa structure, and an insulating film that covers both side surfaces of the upper mesa structure by being in contact with both side surfaces of the upper mesa structure, in which the lower mesa structure includes a first semiconductor layer, above the multiple quantum well layer, and the upper mesa structure includes a second semiconductor layer which is different from the cladding layer in composition, below the cladding layer.

Optical semiconductor device, optical module, and method for manufacturing optical semiconductor device

An optical semiconductor device includes an InP substrate; an active layer disposed above the InP substrate; a n-type semiconductor layer disposed below the active layer; and a p-type clad layer disposed above the active layer, wherein the p-type clad layer includes one or more p-type InAlP layers, the Al composition x of each of the one or more p-type InAlP layers is equal to or greater than a value corresponding to the doping concentration of a p-type dopant, and the absolute value of the average strain amount of the whole of the p-type clad layer is equal to or less than the absolute value of a critical strain amount obtained by Matthews' relational expression, using the entire layer thickness of the whole of the p-type clad layer as a critical layer thickness.

Optical semiconductor device, optical subassembly, and optical module

In an optical transmitter module for combining three or more optical signals different in intensity with an optical multiplexer to generate a PAM signal, the influence of the beat noise and the chromatic dispersion due to the difference in wavelength is reduced. The optical transmitter module includes first through third optical signal sources adapted to output respective optical signals binary intensity modulated with different amplitude from each other, and a combining section. The combining section has a wavelength multiplexer adapted to wavelength-multiplex a plurality of input optical signals having different wavelengths from each other while keeping the respective polarization states, and a polarization multiplexer adapted to polarization-multiplex a pair of input optical signals having respective polarization states perpendicular to each other, and the combining section combines the input optical signals from the first through third optical signal sources with each other to generate a PAM8 signal.

Optical transmitter module

To provide an optical transmitter module with simplified control of a voltage to be applied to an optical modulator. An optical transmitter module includes a semiconductor laser for irradiating a laser beam; a demultiplexer for branching the laser beam to output branched light beams; optical modulators for modulating an optical amplitude of each of the branched light beams into a first optical amplitude or a second optical amplitude, depending on an input level at two levels; and a multiplexer for multiplexing output light beams from the optical modulators. The optical transmitter module may include optical waveguides for connecting the optical modulators and the multiplexer, and the optical waveguides may include a first optical waveguide for causing a first phase difference and a second optical waveguide for causing a second phase difference different from the first phase difference.

A semiconductor optical device includes: a first conductive type semiconductor layer; an active layer; a second conductive type semiconductor layer including a ridge portion; a pair of first grooves, formed on bottom surfaces of both sides of the ridge portion and dividing the active layer; an optical functioning part including the first and second conductive type semiconductor layers, converting a state of light, and having a height higher than a height of the bottom surface of the ridge portion; and a second groove, at least a part thereof being formed on the optical functioning part, an end portion thereof being connected to the first groove, the second conductive type semiconductor layer being divided, and the maximum height of an inner wall surface thereof being higher than the maximum height of an inner wall surface of the first groove.

Semiconductor optical device, optical module, and method for manufacturing semiconductor optical device

Provided is a semiconductor optical device, an arrayed semiconductor optical device, an optical module having a structure to reduce the parasitic capacitance as well as a high design degree of freedom and having a multilayer structure in which a semi-insulating substrate, a first semiconductor layer having one conductive type, an active layer having light emission function, a second semiconductor layer having the other conductive type, an insulating layer, and a conductive layer are stacked in order from the bottom. The multilayer structure includes a light emitting structure, a first electrode structure, and a second electrode structure. In the semi-insulating substrate and the first semiconductor layer, a first grove which separates the second electrode structure from a remaining portion and approaches the second electrode structure with a non-linear shape rather than a linear shape in its entirety is formed.

Semiconductor optical device, arrayed semiconductor optical device, and optical module

In the semiconductor laser including a diffraction grating in which a first diffraction grating region with a first pitch, a second diffraction grating region with a second pitch and a third diffraction grating region with the first pitch, an anti-reflection film coated on an end facet to the light-emitting side, and a reflection film coated on an opposite end facet, the first diffraction grating region is greater than the third diffraction grating region, and the second diffraction grating region is formed, in such a manner that phases of the first and third diffraction grating regions are shifted in a range of equal to or more than 0.6 &#x3c0; to equal to or less than 0.9 &#x3c0;, phases are successive on a boundary between the first and second diffraction grating regions and the phases are successive on a boundary between the second and third diffraction grating regions.

Semiconductor laser and optical semiconductor device

In a BH laser which uses InGaAlAs-MQW in an active layer, Al-based semiconductor multi-layer films including an InP buffer layer and an InGaAlAs-MQW layer, and an InGaAsP etching stop layer are formed in a mesa shape, and a p type InP burial layer is buried in side walls of the mesa shape. An air ridge mesa-stripe of a lateral center that is substantially the same as that of the mesa shape is formed on the mesa shape. According to the present structure, a leakage current can be considerably reduced, the light confinement coefficient can be made to be larger than in a BH laser in the related art, and thereby it is possible to implement a semiconductor laser with a low leakage current and a high relaxation oscillation frequency.

The object of the invention included in the present application is to automatically prevent the deterioration of the image even when the image quality of the projected image is deteriorated due to the replacement of the light source or the like. The following light beam scanning image projection apparatus is one means for achieving the object. In the light beam scanning image projection apparatus including a plurality of light sources which emit the light beams of respectively different wavelengths, a driving section which modulates the intensity of each light beam in accordance with the image signal, the light axis alignment means which aligns the light axes of each light beam, and scanning means which scans the light beams, the light axis alignment means includes: a plurality of optical elements; and an adjusting section which adjusts at least one of a position and a gradient of at least one of the optical elements, and the light beam scanning image projection apparatus further includes: detecting means which detects a shift between a spot center of each light beam and a center reference point; and position correction means which controls the adjusting section based on a detection result in the detecting means to adjust at least one of the position and the gradient of at least one of the optical elements of the light axis alignment means, thereby aligning the light axes of each light beam.

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Tokyo, Japan

Kouji Nakahara