Photonics Electronics Technology Research Association

Nec Corporation

Aio Core Co., Ltd.

Kenichiro Yashiki

Kazuhiko Kurata

Takeshi Akagawa

Naofumi Suzuki

Masayoshi Tsuji

Hiroshi Hatakeyama

Kimiyoshi Fukatsu

Takayoshi Anan

Yasuyuki Suzuki

Masatoshi Tokushima

Jun Ushida

Provided is a light receiving element with high light receiving sensitivity. The light receiving element comprises: a light absorbing layer that absorbs light to generate a carrier; and a diffraction element that converts the optical path of first polarized light, which is obliquely incident on a plane formed by the light absorbing layer, so that the first polarized light propagates in a first direction along the light absorbing layer, and that converts the optical path of second polarized light incident from the same direction as the first polarized light so that the second polarized light propagates in a second direction, opposite the first direction, along the light absorbing layer.

Photodetector having one-dimensional grating structure

The purpose of the present invention is to allow a silicon photonics modulator to be operated at high speed with high frequency by providing an electrode structure for the small multichannel high-density silicon photonics modulator. This electrode structure for a silicon photonics modulator includes, on the planar surface of a silicon substrate, a first layer for forming a plurality of bias electrical wirings, and a second layer formed by aligning each of a plurality of ground electrode portions and each electrical wiring in the first layer.

Electrode structure for silicon photonics modulator

A pad-array arrangement structure on a substrate for mounting an IC chip on the substrate, wherein a structure with which it is possible to maximally avoid an increase in the number of wiring layers on the substrate is obtained by devising the pad arrangement in an IC pad-array region. A embodiment of the present invention provides a pad-array structure on a substrate for mounting an IC chip on the substrate. The present invention is characterized in that: a plurality of ground pads arrayed equidistantly in a first row, and a plurality of signal pads arrayed equidistantly in a second row on the inside of and parallel to the first row, are provided on a first circumferential edge in the pad-array region; each of the signal pads passes between two adjacent ground pads in the first row and is connected to an external circuit on the substrate; and electrical signals are input to and output from the external circuit.

Pad-array structure on substrate for mounting IC chip on substrate, and optical module having said pad-array structure

A semiconductor integrated circuit that reduces a loss in an electrical signal and a method for manufacturing the semiconductor integrated circuit are provided. The semiconductor integrated circuit comprises a first region on which an optical circuit is to be formed and a second region on which an electrical signal wiring is to be formed. The first region comprises an Si substrate (), a BOX layer () formed on the Si substrate (), a first SOI layer () formed as an optical circuit on the BOX layer (), and a first SiOlayer () formed on the first SOI layer (). The second region comprises the Si substrate (), the BOX layer (), a second SiOlayer () formed on the BOX layer (), and an electrical signal wiring () formed on the second SiOlayer ().

Semiconductor integrated circuit and method for manufacturing the same

This present invention is provided with: a semiconductor laser for emitting laser light in a plurality of channels; optical waveguides optically coupled in a corresponding manner to the semiconductor lasers, the optical waveguides propagating laser light as input light for each channel; optical modulators for modulating the input light and generating an optical signal; and an optical signal output unit coupled to the optical modulators, the optical signal output unit outputting the optical signal propagated from the optical modulators to the exterior. The present invention is characterized in that the semiconductor laser is arranged on the opposite side from an optical branching unit and the optical modulators, with the optical signal output unit interposed therebetween, in the plane of an opto-electric hybrid board.

Optical transmitter or transmission unit in optical transmitter/receiver provided on opto-electric hybrid board

An optical circuit, wherein the effects of reflected light generated by an optical component are reduced. The optical circuit () is provided with an optical branching () for branching light, an optical coupler () for coupling a first portion of branched light to an optical waveguide () for transmission, and an optical reflecting unit () for reflecting a second portion of the branched light, the phase difference between the reflected light from the optical coupler () and the reflected light from the optical reflecting unit () being (2m&#x2212;1)&#x3c0; (where m is an integer) on an input side of the optical branching ().

Optical circuit

The present invention provides a surface-emission type semiconductor laser wherein an effective length of a cavity is reduced, thereby enabling to realize a higher-speed direct modulation. In the surface-emission type semiconductor laser according to the present invention, when supposing the optical path length (L) of a resonator part relative to a lasing wavelength &#x3bb;to be given as 0.9&#xd7;&#x3bb;&#x2266;L&#x2266;1.1&#xd7;&#x3bb;, and denoting the refractive indexes of a high refractive index layer and a low refractive index layer of a dielectric DBR by nand n; the average refractive index within an optical path length &#x3bb;/4 in the semiconductor in contact with the dielectric DBR by n; and the refractive indexes of the high refractive index layer and the low refractive index layer of a semiconductor DBR by nand n, respective materials to be used are selected so as to satisfy the following conditions (1) and (2):()()(),&#x2003;&#x2003;(1)

Surface-emission type semiconductor laser

An optical communication system for performing data transmission with optical signals comprises a first optical transmitter and a first optical receiver. The first optical transmitter has a first surface-emitting laser including an active layer of a multiple quantum well structure having a quantum well layer of InGaAs (0.15&#x2266;x&#x2266;0.35), the first surface-emitting laser having an oscillation wavelength ranging from 1000 nm to 1100 nm inclusive. The first optical transmitter transmits an optical signal generated by the first surface-emitting laser. The first optical receiver is connected to the first optical transmitter by a first optical transfer path, and receives the optical signal transmitted from the first optical transmitter through the first optical transfer path.

Optical communication system and optical transmitter

A surface emitting laser is provided with a first multilayer Bragg reflecting mirror including a first layer, a second multilayer Bragg reflecting mirror including a second layer, and an optical resonator unit that is held between these multilayer Bragg reflecting mirrors and includes an active layer. Further, the optical resonator unit contacts with the first layer and second layer respectively. The effective refraction index nof the resonator unit is larger than either the first layer or the second layer, and an optical length nL of the optical resonator unit has a relationship with an oscillating wavelength &#x3bb; of the surface emitting laser to satisfy the following relationship: 0.5&#x3bb;&#x3c;nL&#x2266;0.7&#x3bb;.

Growing community of inventors

Tokyo, Japan

Kenichiro Yashiki