Opnext Japan, Inc.

Masanobu Okayasu

Osamu Kagaya

Naoki Matsushima

Hiroyasu Sasaki

Michihide Sasada

Toshiaki Takai

Kazuhiko Naoe

Kenji Yoshimoto

Hiroyuki Arima

Tetsuya Kato

Kazumi Kawamoto

Hiroshi Yamamoto

Takuma Ban

Noriko Sasada

Kazuhise Uomi

A metal pattern for a high frequency signal is patterned on a flexile substrate, and the flexile substrate is bent in such a way as to form a substantially right angle at a spot corresponding to an end of the metal pattern for the signal. And an end of the metal pattern is fixedly attached to a lead pin for signaling, attached to a stem, for electrical continuity, so as to be in a posture horizontal with each other. Meanwhile, a part of the lead pins attached to the stem, being in such a state as penetrated through respective holes provided in the flexible substrate, is fixedly attached to a part of metal patterns provided on the flexible substrate so as to ensure electrical continuity therebetween.

Optical semiconductor device with flexible substrate

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

To provide a small-sized and reliable optical module in which a light emitting element and an optical function element respectively remarkably different in a coefficient of thermal expansion are mounted in the same casing, in the invention, the optical function element is mounted on the casing made of first material substantially equal in a coefficient of thermal expansion to the optical function element, a light emitting element unit including the light emitting element (for example, a thermoelectric module over which the light emitting element is mounted) is mounted on a member (base material) made of second material different from the first material and matched with the light emitting element unit in a coefficient of thermal expansion, and the member is, for example, embedded in the bottom of the casing.

Optical module

The present invention provides a structure that makes high-frequency transmission possible in an optical module and in the optical transmission apparatus using the module. The invention has means that excludes, from the service band of the optical module, frequency of the standing waves occurring at connection between the first high-frequency signal line substrate and second high-frequency signal line substrate in the optical module.

Optical module and optical transmission apparatus

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

The present invention provides an optical modulator module comprising: a chip carrier; a semiconductor optical modulator for modulating light based on an electronic signal; a strip conductor electrically connected to the semiconductor optical modulator; a first resistor electrically connected to the semiconductor optical modulator; and a second resistor electrically connected in series to the first resistor; wherein the semiconductor optical modulator, the strip conductor, and the first and second resistors are disposed on the chip carrier; and wherein the frequency characteristics of the optical modulator module is adjusted by selecting to short or not to short both ends of the first resistor by use of a wire as necessary.

The present invention provides a compact, highly reliable optical module in which a light-emitting element and optical modulator element that differ from each other in thermal expansion coefficient are mounted in one casing. In the optical module having a differential thermal expansion coefficient less than 5&#xd7;10[1/K] between the light-emitting element and the casing, and a differential thermal expansion coefficient of at least 5&#xd7;10[1/K] between the optical modulator element and the casing, a section at which the optical modulator element and the casing are fixed is equal to or less than 10 mm wide in the direction of an optical axis.

Growing community of inventors

Yokohama, Japan

Masanobu Okayasu