Fujitsu Corporation

Photonics Electronics Technology Research Association

Sumitomo Electric Device Innovations, Inc.

Akinori Hayakawa

Ken Morito

Kazumasa Takabayashi

Shinji Tadaki

Takuya Fujii

Nobuhiro Imaizumi

Toshiya Akamatsu

Yoshihiro Sato

Shigeaki Sekiguchi

Takeshi Matsumoto

Norihiko Sekine

An optical circuit module comprises a substrate with a first optical coupler connected to a first optical waveguide and a second optical coupler connected to a second optical waveguide on a substrate surface side; and a semiconductor photonic device mounted on the substrate, wherein the semiconductor photonic device has a third optical waveguide and a fourth optical waveguide extending to a first end face that faces the substrate surface, and wherein the third optical waveguide is optically connected to the first optical coupler and the fourth optical waveguide is optically connected to the second optical coupler.

Optical circuit module, optical transceiver using the same, and semiconductor photonic device

An optical modulation apparatus includes an optical modulation unit that includes a plurality of ring optical modulators which are coupled in cascade to each other and the ring optical waveguides of which have round-trip lengths different from each other, and a controller that performs, for at least one of the ring optical modulators, first resonance wavelength adjustment control to adjust the resonance wavelength of the ring optical modulator to one input light wavelength, performs second resonance wavelength adjustment control to specify the ring optical modulator that exhibits a minimum current amount required for the adjustment of the resonance wavelength of the ring optical waveguide to the one input light wavelength from among the ring optical modulators and adjust the resonance wavelength of the specified ring optical modulator to the one input light wavelength, and performs modulation driving control for the specified ring optical modulator.

Optical modulation apparatus, optical transmitter and controlling method for optical modulator

An optical functional device includes: a photodetector; a first optical waveguide which is connected to one end face of the photodetector; and a second optical waveguide which is connected to the other end face of the photodetector. The photodetector is formed in a multi-mode interferometer and has electrodes. Light input from the first optical waveguide to the photodetector focuses image at a position physically away from the second optical waveguide, and light input from the second optical waveguide to the photodetector focuses image at a position physically away from the first optical waveguide.

Optical functional device, optical receiving apparatus and optical transmission apparatus

An optical resonator apparatus includes an optical resonator unit wherein ring optical resonators each including a first optical waveguide and a resonance wavelength adjustment electrode are coupled in cascade connection and round-trip lengths of the ring optical waveguides are different from each other and vary in order from an input side to an output side, and a controller that adjusts a resonance wavelength of each ring optical resonator in order beginning with the ring optical resonator provided at the most input side so as to match with an input light wavelength and, when an inter-channel occurs, adjusts the resonance wavelength of the first ring optical resonator from the input side so as to match with a second-matching input light wavelength and adjusts the resonance wavelengths of the second and succeeding ring optical resonators from the input side so as to match with the first-matching input light wavelength.

Optical resonator apparatus, optical transmitter and controlling method for optical resonator

An optical device includes: an optical integrated circuit chip that comprises an optical integrated circuit and an optical interface connected thereto; an electronic circuit chip that comprises an electronic circuit connected to the optical integrated circuit; a through wiring board that comprises a through wiring connected to the electronic circuit chip; a first bump that connects the optical integrated circuit and the electronic circuit between the optical integrated circuit chip and the electronic circuit chip; a second bump that connects the electronic circuit and the through wiring between the electronic circuit chip and the through wiring board; and a third bump connected to an end portion on an opposite side to the second bump of the through wiring. The optical integrated circuit chip and the through wiring board are disposed on a side of a first main surface of the electronic circuit chip. A first distance between the first main surface and a second main surface of the optical integrated circuit chip, the second main surface being on an opposite side to the electronic circuit chip, is equal to or smaller than a second distance between the first main surface and a vertex of the third bump, the vertex being on an opposite side to the electronic circuit chip.

Optical device and optical module

An optical semiconductor device includes a semiconductor substrate; a lower cladding layer formed over the semiconductor substrate; a quantum well active layer formed on the lower cladding layer; a diffraction grating layer formed over the quantum well active layer and having diffraction gratings formed in a surface thereof; and an upper cladding layer formed on the diffraction gratings of the diffraction grating layer. Further, a band gap in outer regions of the quantum well active layer that are adjacent to outer end surfaces of the optical semiconductor device is greater than the band gap in an inner region of the quantum well active layer that is located between the outer regions, and a thickness of one or more layers, which include the lower cladding layer and positioned between the semiconductor substrate and the quantum well active layer, is greater than or equal to 2.3 &#x3bc;m.

Optical semiconductor device and method of manufacturing the same

An optical semiconductor element includes: a grating base layer including a projection-recess structure disposed over a substrate; and a grating cover layer including a group III-V semiconductor having three or more elements, wherein the grating cover layer includes a first region which is disposed over recessed portions of the grating base layer and which has a compositional ratio of a group III-V semiconductor having a first refractive index, and a second region which is disposed over projecting portions of the grating base layer and which has a compositional ratio of a group III-V semiconductor having a second refractive index that is smaller than the first refractive index, wherein the grating base layer includes a group III-V semiconductor having a third refractive index that is smaller than the first refractive index.

Optical semiconductor element, semiconductor laser, and method of manufacturing optical semiconductor element

An optical demultiplexer has first and second input ports and first and second output ports. When optical signal is introduced into the first input port, intensity of optical signal output from the first output port is equal to that from the second output port. When optical signal is introduced into the second input port, intensity of optical signal output from the first output port is larger than that from the second output port. An optical multiplexer has third and fourth input ports and third and fourth output ports. A first optical waveguide connects between the first output port and the third input port, while a second optical waveguide connects between the second output port and the fourth input port. Voltages applied to a first modulation electrode and a second modulation electrode work to cause changes in the optical path lengths of the first optical waveguide and the second optical waveguide.

Optical semiconductor device

When phases of lights passing through arms are adjusted, a first DC bias and a first modulation signal are applied to one arm from one modulating electrode, and a second DC bias and a second modulation signal are applied to the other arm from the other modulating electrode. The first and second DC biases are applied to the modulating electrodes such that a rate of a product of a length of one modulating electrode and the first DC bias and a product of a length of the other modulating electrode and the second DC bias is kept at a constant value. According to this constitution, it is possible to enable an optimum control of a phase difference between the arms and a precise control of wavelength chirp characteristics with a simple element constitution, and an optical modulation of which device size is small and having fine characteristics is enabled.

Optical modulation device, driving method of optical modulation device, and manufacturing method of optical modulation device

A light emitting device includes a semiconductor laser, which oscillates in a single longitudinal mode, formed above a semiconductor substrate, a first heater, which controls a temperature of the semiconductor laser, provided near the semiconductor laser, a gain unit, which amplifies a beam outputted from the semiconductor laser and outputs an amplified beam, formed above the semiconductor substrate, a second heater, which controls a temperature of the gain unit, provided near the gain unit, and a second harmonic generation element, which converts the amplified beam outputted from the gain unit to a second harmonic light and outputs the second harmonic light.

Light emitting device and method of controlling light emitting device

A first optical waveguide of a convex shape is formed over a substrate. A second optical waveguide of a convex shape is formed over the substrate. A multimode interference waveguide of a convex shape is formed over the substrate for optically coupling the first optical waveguide to the second optical waveguide. Either side of the first optical waveguide is filled with a filling material, but either side of the second optical waveguide is not filled with the filling material.

Optical waveguide device, its manufacture method, laser module and optical transmission system

Objects are achieved by an optical semiconductor device comprising: a structureincluding a substrate, a diffraction grating, an active layerand a refractive index control layer; and an laser elementincluding an electrodefor the active layer, an electrodefor the refractive index control layer and an electrodefor switching, wherein a pre-bias current is previously supplied from the electrodefor the active layer to the active layerin a state where a switching current is not supplied from the electrodefor switching to the active layer, and then while a current Ifor activation is supplied from the electrodefor the active layer to the active layer, the laser elementis turned on by supplying the switching current Ifrom the electrodefor switching to a part of the active layer, as well as turning off the laser elementby halting the supply of the switching current I.

Optical semiconductor device and driving method thereof

An optical semiconductor device includes a semiconductor laser, a first optical waveguide, an optical coupler for branching light guided from the semiconductor laser through the first optical waveguide into two lights, two second optical waveguides, diffraction gratings provided individually on the two second optical waveguides, and an optical detector for detecting light guided through one of the two diffraction gratings, and the components are provided on the same substrate. The optical semiconductor device is configured such that reflection returning lights from the diffraction gratings side to the semiconductor laser side interfere with each other and thereby extinguish each other at the optical coupler and the phases of the reflection returning lights from the diffraction gratings side are displaced from each other by &#x3c0; at the optical coupler portion.

Growing community of inventors

Sagamihara, Japan

Akinori Hayakawa