Nippon Telegraph and Telephone Corporation

Shunichi Souma

Shinji Mino

Takashi Goh

Motohaya Ishii

Takashi Yamada

Akira Himeno

Masayuki Okuno

Takeshi Kitagawa

Masao Kato

Hiroshi Takahashi

Takayuki Mizuno

Takashi Kurihara

Kazuo Fujiura

Manabu Oguma

Tsutomu Kitoh

An optical module controls its output characteristics electrically and an optical switch constitutes the optical module. An optical waveguide circuit (PLC) and an electronic circuit (IC) for driving the PLC are mounted on the same substrate. The IC is composed of a bare chip to be molded afterward. Wiring of the IC is grouped and integrated on the PLC substrate to achieve higher density and miniaturization of the optical module.

Optical module and optical switch

The present invention discloses an interferometer optical switch that can carry out switching over a broad band and has a high extinction ratio and large fabrication tolerance. The interferometer optical switch employs a phase generating coupler, the phase difference of the output of which has wavelength dependence, as at least one of the optical multi/demultiplexing device included in the interferometer optical switch. A wavelength insensitive interferometer optical switch is implemented by making the sum 2&#x3c0;{&#x3c6;(&#x3bb;)+&#x3c6;&#x394;(&#x3bb;)+&#x3c6;(&#x3bb;)} constant regardless of the wavelength, where &#x3c6;(&#x3bb;) is the phase produced by the first optical multi/demultiplexing device, 2&#x3c0;&#x3c6;&#x394;(&#x3bb;) is the phase difference of the optical delay line with an optical path length difference of &#x394;L, and 2&#x3c0;&#x3c6;(&#x3bb;) is the phase produced by the second optical multi/demultiplexing device.

Interferometer optical switch and variable optical attenuator

In an optical multiplexing communication system, a frequency conversion of the optical multiplexed signals having different amplitudes for different communication channels into a plurality of optical pulse sequences having different carrier frequencies for different communication channels is carried out, and the plurality of optical pulse sequences obtained by the frequency conversion are demultiplexed into optical pulse sequences for different communication channels.

Optical multiplexing communication system using ultra high speed signal transmission

Optical module and optical switch constituting the same

An optical module controls its output characteristics electrically and an optical switch constitutes an optical module. An optical waveguide circuit (PLC) and an electronic circuit (IC) for driving the PLC are mounted on the same substrate. The IC is composed of a bare chip to be molded afterward. Wiring of the IC is grouped and integrated on the PLC substrate to achieve higher density and miniaturization of the optical module.

Growing community of inventors

Yamato, Japan

Shunichi Souma