Oki Electric Industry Co., Ltd.

Toshimasa Ishida

Hideaki Okayama

Kazuhiro Watanabe

Issei Asabayashi

Katsuzo Kaminishi

Toshio Nonaka

Hiroki Yaegashi

A waveguide-type optical device of the invention has a dielectric substrate, wave-guiding paths formed in the dielectric substrate, and electrodes for forming an operation-controlling electric field for the wave-guiding paths. A carrier capture layer is provided in a region into which carriers are injected from at least one of the electrodes.

Waveguide-type optical device

There is provided an optical wave-length filter which is constituted by a wave-guide route formed on a surface of a substrate; a front stage polarizer disposed in the wave-guide route for transmitting as an input light either TM mode light or TE mode light; a plurality of mode-converters disposed in the wave-guide route for mode converting one TM/TE-mode light transmitted from the front stage polarizer having a conversion wave length corresponding to an output light of the optical wave-length filter into the other TE/TM-mode light; and a rear stage polarizer disposed in the wave-guide route for transmitting as the output light of the optical wave-length filter the other TE/TM-mode light; the mode-converters being constituted by a finger-type electrode for control and a finger-type electrode for earthing interdigitally coupled for each other and disposed along the wave-guide route.

Optical wave-length filter and a driving method thereof

Waveguide-type optical switch comprising a substrate, branched first and second waveguide routes provided thereon, and an electrode(s) provided on the substrate for controlling the propagation-constant difference or refractive index difference between the first and second waveguide routes. The interval between the first and second waveguide routes is extended towards the terminal end sides from the branch point side of the waveguide routes. The first and second waveguide routes are provided with a branched part. The first and second waveguide routes are provided with at least one part of the bending portions (II) connected to the branch part, respectively. The local branch angle between the first and second waveguide routes on the side of starting ends of the bending portions (II) is enlarged while the local branch angle between the first and second waveguide routes on the side of terminal ends at the bending portions (II) is reduced.

Waveguide-type optical switch

An optical switching system has an optical transmission path for propagating signal beams, and a plurality of optical nodes for transmitting and receiving the signal beams. A reference beam source generates reference beams each having a particular wavelength. Each optical node generates a plurality of signal beams which are tuned to the wavelengths associated with the reference beams.

Optical switching system which employs reference beams with different

A semiconductor device and a method of manufacturing the same are disclosed. The device comprises a GaAs semiconductor body, a source and a drain region formed in the semiconductor body, a channel region placed between the source and drain regions, a source and a drain electrodes provided by patterning treatment onto the surfaces of the source and drain regions and making ohmic contact thereto, and a gate electrode provided onto the surface of the channel region and consisting of a W-Al alloy. The method comprises steps of providing a GaAs semiconductor body as a substrate, forming an active layer into the body, forming a pattern of a W-Al alloy as a gate electrode, implanting donor ion with high concentration into a region including a portion of the active layer other than the underlying region of the portion on which the gate electrode is at least provided thereby forming a source and a drain region, subjecting the semiconductor body to an annealing treatment to activate the active layer and the source and drain regions, and providing ohmic contacts onto the source and drain regions.

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Tokyo, Japan

Toshimasa Ishida