Opnext Japan, Inc.

Kazuhiko Naoe

Noriko Sasada

Osamu Kagaya

Kazuhisa Uomi

Masataka Shirai

Hideo Arimoto

Masanobu Okayasu

Satoshi Tada

Masahiro Aoki

Minoru Fujita

Hiroyuki Kamiyama

Seiji Sumi

Hiroyuki Arima

Tetsuya Kato

Kazuhise Uomi

A wavelength tunable laser module for DWDM is used, in which a single electroabsorption modulator integrated laser is mounted and an oscillation wavelength is made tunable by temperature control. Driving conditions of a laser and a modulator are determined such that they have approximately the same modulation and transmission characteristics in a temperature control range. Such an electroabsorption modulator integrated laser is used and the driving conditions are incorporated, thereby a small, inexpensive wavelength tunable optical transmitter can be provided.

Wavelength tunable optical transmitter and optical transceiver

A chip carrier includes a metal-coated portion formed on a front surface of a substrate and to be mounted a device, and a rear surface of the substrate being coated with a metal, in which a metal-coated portion is formed on a side surface of the substrate and the metal-coated portion on the front surface of substrate is connected with the metal-coated portion on the rear surface by the metal-coated portion formed on the side surface of the substrate, thereby maintaining frequency characteristics of the optical semiconductor device.

Structure of chip carrier for semiconductor optical device, optical module, and optical transmitter and receiver

A semiconductor optical device has a semiconductor laser portion and a modulator portion which have different mesa structures. The mesa structure of the semiconductor laser portion is a ridge waveguide structure which has air around the mesa. The mesa structure of the modulator portion is a planarized ridge waveguide structure which has an organic insulator buried around the mesa.

Semiconductor optical device and optical transmission module

This invention provides an optical transmitter module and an optical module using an EA modulator capable of realizing stable ACER regardless of operating temperature without using a control mechanism for maintaining temperature of the EA modulator constant. In the EA modulator, optical waveguides formed of a multi-layered film are formed on a substrate, an electrical signal is applied to the optical waveguides in a direction vertical to the substrate, and the input light absorption amount is changed to control the amount of output light. Also, a plurality of p-side electrodes electrically separated from each other for applying an electrical signal to the active layer optical waveguides are arranged on optical axes of active layer optical waveguides. The length of optical waveguides to which the electrical signal is applied is changed by controlling the number of p-side electrodes to which the electrical signal is applied in accordance with temperature.

Semiconductor electro-absorption optical modulator, semiconductor electro-absorption optical modulator integrated laser, optical transmitter module and optical module

A high frequency substrate, on which a high frequency substrate transmission line for connecting a chip carrier transmission line and a package substrate transmission line is formed, is mounted while being inclined with respect to a package, so that each distance between the transmission lines can be reduced. Thereby, the lengths of wires for connecting the transmission lines can be reduced so as to improve frequency characteristics of an optical modulator module.

Optical modulator module

Even for a driving impedance of 25 &#x3a9;, high transmission waveform quality of an optical transmission module is maintained using an optical modulator element designed for a driving impedance of 50 &#x3a9;. The above can be achieved by adopting an optical modulethat includes an input electrode for electrical signals, an optical modulator element for modulating laser light using the electrical signals, a termination resistance element, a first bonding wire for connecting the input electrode and the optical modulator element, a second bonding wire for connecting the optical modulator element and the termination resistance element, and a third bonding wire for connecting the input electrode and the termination resistance element.

Optical module

For achieving a transmission light source having different transmission properties or characteristics, i.e., the a parameters, depending upon application thereof, in a light emission element of semiconductor EA modulator integrated type being constructed with a light emission portion for lasing with a single vertical mode and a plurality of EA modulators, wherein an absorption edge wavelength under the condition of applying no bias thereto, in the semiconductor multiple-quantum-well structure owned by the modulator which is near to an emission side of the light emission portion, is to be equal or longer than the absorption edge wavelength owned by the modulator positioned far from the emission side of the light emission portion.

Growing community of inventors

Yokohama, Japan

Kazuhiko Naoe