Nippon Telegraph and Telephone Corporation

Ricoh Company, Ltd.

Yuta Ueda

Yuki Sato

Shiro Akama

Hiroyuki Ishii

Koji Takeda

Takushi Kazama

Josuke Ozaki

Hitoshi Wakita

Mami Akiyama

Sakie Higuchi

Hiroki Ishimitsu

Shigeru Kanazawa

Yoshihiro Ogiso

Takahiko Shindo

Naoki Fujiwara

Kazuhiko Kobayashi

Kota Shikama

Toshihiro Shimada

Nobuhiro Kikuchi

Tsuyoshi Endo

Shinsuke Nakano

Eiichi Yamada

Meishin Chin

Makoto Yoshioka

Hidehiko Maeda

Tsutomu Osawa

Tomonari Sato

Takushi Saito

An optical semiconductor chip of the present disclosure includes a high frequency line between an electrode pad receiving a modulation signal and a modulation electrode on the optical waveguide having a light absorption layer. The depletion layer capacitance generated in the light absorption layer is canceled by an inductor component of the high frequency line. When a portion directly below the high frequency line is embedded with a low-dielectric-constant material or is made hollow, the parasitic capacitance is further reduced. The high frequency line may have a zigzag shape as well as a linear shape. The electrode pad on the optical semiconductor chip can be connected to other substrates including RF lines for modulation signal input by bumps or wire bonding.

Optical semiconductor chip

An optical waveguide is an optical waveguide including a semiconductor quantum well structure, the optical waveguide including a first region in which the semiconductor quantum well structure is not disordered and a second region in which the semiconductor quantum well structure is disordered. The first region has a first bandgap wavelength, the second region has a second bandgap wavelength, and a region in which the semiconductor quantum well structure is disordered in such a manner that a bandgap wavelength continuously decreases from the first bandgap wavelength to the second bandgap wavelength is provided between the first region and the second region.

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

An optical circuit is provided in which electric circuit parts and optical circuit parts are integrated in a stack on a printed substrate. The optical circuit is provided with a lid having a temperature regulation function that uses a temperature control element and an optical fiber block capable of optical input and output. Temperature control of optical circuit elements can be efficiently performed by mounting electric circuit parts and optical circuit parts on a printed substrate in advance by a reflow step using OBO technology and subsequently attaching a lid that includes a temperature control element.

Optical circuit

A semiconductor device includes an electrode which is arranged on an organic material with an insulation film interposed therebetween and which does not easily peel away from the organic material along with the insulation film. An insulation film in a region including pad portions of a phase shift electrode and a modulation electrode has openings at the centers of the pad portions of the phase shift electrode and the modulation electrode, the edge portions of which are formed on the phase shift electrode and the modulation electrode. In this way, the adjoining edges of the phase shift electrode and modulation electrode and the insulation film are all covered by the insulation film so as not to be exposed to the atmosphere. By covering the cracks that occur in the insulation film in the production process with the insulation film made of SiO, SiN, SiONor the like, an organic solvent such as acetone or ethanol used in the process can be prevented from seeping in between the insulation film and the organic material through the cracks in the insulation film.

Semiconductor device

An optical module includes: a substrate; one or more light sources that produce light that is an optical signal; one or more light reflection units that change the direction of travel of the light to a direction substantially perpendicular to the substrate; one or more optical waveguides that optically connect the one or more light sources and the one or more light reflection units to each other; and a lid that is attached to the substrate to cover the one or more light sources, the one or more light reflection units and the one or more optical waveguides. The lid has one or more lenses that collimate light directed by the one or more light reflection units and transmit the light to the outside of the lid.

Optical module, optical wiring substrate, and method for manufacturing optical module

There is provided an optical element mounted on a substrate and an optical coupling element mounted on the substrate. The optical coupling element includes a guide unit extending in a direction parallel to a plane of the substrate so as to fix an optical fiber. There is provided a mold resin layer formed on the substrate so as to cover the optical element and expose a side surface of the optical coupling element at one end of the guide unit. The optical element includes a light incidence/emission unit on a side surface perpendicular to the plane of the substrate, and the other end of the guide unit and the light incidence/emission unit are disposed to face each other.

Optical component and method for manufacturing same

To provide an optical module, an optical wiring board, and a method for manufacturing an optical module that provide the two-dimensional freedom degree of the joint portion between the optical module and the optical fiber even through the OBO method is applied to an optical module mounted via WLP. The optical module includes a board, a plurality of optical input-output portions that change a travel direction of light traveling substantially orthogonally to the board to a direction substantially parallel to the board and change a travel direction of the light traveling substantially parallel to the board to a direction substantially orthogonal to the board, one or more optical waveguides that optically connect the optical input-output portions to each other, and a lid that is attached to the board so as to include the optical input-output portions and the one or more optical waveguides, in which the lid has one or more reflection mirrors that change a travel direction of the light traveling from an outside of a side surface of the lid to an inside of the side surface so as to be directed to the optical input-output portions and change a travel direction of the light output from the optical input-output portions so as to be directed from the inside of the side surface of the lid to the outside of the side surface.

Optical module, optical wiring board, and production method for optical module

Provided is an optical modulator having an optical modulation high frequency line through which a high frequency electrical signal can be efficiently input to an optical modulation region and which is in a broadband. High frequency lines of an optical modulator, that is, an input high frequency line, an optical modulation high frequency line, and an output high frequency line have a line configuration in which each of the input high frequency line and the output high frequency line is divided into a plurality of segments, and adjacent segments of the plurality of the segments have different characteristic impedances and propagation constants. The input high frequency line and the output high frequency line may be implemented by changing a width or a thickness of a signal electrode formed on a dielectric forming a micro-strip line between adjacent segments. The characteristic impedances and the propagation constants may be changed by changing a dielectric constant of the dielectric instead of changing the width or the thickness of the signal electrode.

Optical modulator

A Mach-Zehnder modulator is enabled to perform high-speed modulation operation by reducing RF loss of a high-frequency wiring formed on an optical waveguide without deteriorating optical characteristics of branching and multiplexing optical circuits. The Mach-Zehnder modulator includes a Mach-Zehnder (MZ) optical waveguide including two arm waveguides, a 1&#xd7;2 multimode interference coupler composed of a semiconductor that splits and distributes input light to the two arm waveguides, a 2&#xd7;1 multimode interference coupler composed of a semiconductor that multiplexes light from the two arm waveguides, and phase modulation means for giving a phase difference to the light that propagates through the two arm waveguides, wherein the 1&#xd7;2 multimode interference coupler and the 2&#xd7;1 multimode interference coupler are formed in a high-mesa structure, and higher mode light radiation means for radiating higher mode light is connected to only the 2&#xd7;1 multimode interference coupler among the two multimode interference couplers.

Semiconductor Mach-Zehnder optical modulator and IQ optical modulator using same

A high-frequency transmission line is provided that improves a high-frequency characteristic. The high-frequency transmission line includes a first conductor line, a termination resistance connected to the first conductor line, a second conductor line connected to the termination resistance, and a ground line that is provided to be opposed to the first conductor line, the termination resistance, and the second conductor line to have a predetermined distance thereto and that is connected to the second conductor line. The first conductor line and the ground line are formed to have a line width decreasing toward the termination resistance, respectively.

High-frequency transmission line and optical circuit

An IQ optical modulator including: a parent Mach-Zehnder type (MZM) optical waveguide; child MZM optical waveguides constituting two arms of the parent MZM; two electrode transmission lines provided along the two arms of the child MZM, respectively, and receiving modulation signal to phase-modulate an optical signal; an RF extension line connected to the two electrode transmission lines, respectively; a first optical splitter branching light into the two arms of the parent MZM; a second optical splitter branching light into the two arms of the child MZM; and a first optical multiplexer multiplexing light from the two arms of the child MZM, wherein stripe direction of the child MZM optical waveguide is same as the RF extension line, the second optical splitter, and the first optical multiplexer, and is orthogonal to the first optical splitter.

IQ optical modulator

According to an embodiment, an electronic device includes a heat source, a discharge path, a wall internal space, and a heat conductor. The discharge path is configured to guide a gas toward the outside of the device. The wall internal space is surrounded by walls, extends vertically, and is open to a space outside the device via an upper opening and a lower opening that are in different vertical positions. The heat conductor includes a heat absorber that is positioned in the discharge path and a heat dissipater that is positioned in the wall internal space.

Electronic and image forming device with gas ventilation

A lock lever structure includes a shaft; a cam attached to the shaft to fit a different-shaped portion of the shaft to prevent rotation of the cam in a circumferential direction of the shaft, the different-shaped portion having a different shape in cross section from a round portion of the shaft; a lever having an inner hollow cylindrical portion larger than an outline of the shaft and attached to the shaft to be rotatable in the circumferential direction of the shaft; a spring attached to the shaft to press the cam and the lever in an axial direction of the shaft; and a retainer attached to the shaft to retain the spring, the cam, and the lever to the shaft. The cam has at least two valley portions. The lever has a contact portion to contact the cam. The contact portion has a base shape.

Lock lever structure, unit, and image forming apparatus

An image forming apparatus includes a first human body detector, a second human body detector, and a controller. The first human body detector has a first detection span to detect a human body to output a signal. The second human body detector has a second detection span to detect a human body to output a signal. The controller changes a state of the image forming apparatus from a standby state to an operation state in accordance with the output signal from each of the first human body detector and the second human body detector. A first center line of the first detection span intersects with a second center line of the second detection span at a portion where the first detection span and the second detection span overlap with each other in a planar view.

Image forming apparatus

A housing structure includes an exterior cover having an opening through which an interior of the exterior cover communicates with an exterior of the exterior cover, an interior cover disposed inside the exterior cover and facing the exterior cover with a clearance secured therebetween, an inward projection projecting from the exterior cover to the interior cover, and an outward projection projecting from the interior cover to the exterior cover. The inward projection and the outward projection define an airflow passage in the clearance between the exterior cover and the interior cover, and the airflow passage includes multiple bent portions. The outward projection is greater in width than the inward projection in an airflow direction toward the opening, and the airflow direction perpendicular to a direction in which the interior cover faces the exterior cover.

Growing community of inventors

Tokyo, Japan

Yuta Ueda