Oki Electric Industry Co., Ltd.

Nippon Telegraph and Telephone Corporation

Other

Ntt Electronics Corporation

Kawasaki Jukogyo Kabushiki Kaisha

Kokusai Denshin Denwa Co., Ltd.

Kitanihon Electric Cable Co., Ltd.

Yasuaki Tamura

Yuichi Suzuki

Hirotsugu Sato

Haruki Kozawaguchi

Yoshito Shuto

Masahiro Yanagisawa

Toshikazu Hashimoto

Kenji Yokoyama

Yasufumi Yamada

Satoru Tomaru

Saburo Imamura

Ikuo Ogawa

Kiyofumi Mochizuki

Akio Sugita

Yoshiyuki Doi

Masayoshi Ohno

Kuniharu Kato

Akimasa Kaneko

Michiyuki Amano

Makoto Hikita

Eiichi Nishimura

Fumio Nakamura

Ryoko Yoshimura

Takaharu Ohyama

Shuichi Yanagi

Shunichi Tohno

Yuji Akahori

Yoshiharu Kubo

Yuto Yamashita

Minoru Tamura

Etsuo Ogino

Keiichi Sasaki

Munenori Ishikawa

Kunihiko Mano

Hiroshi Nakazawa

Shinichiro Ina

Takeo Senuma

Shunichi Tono

The degassing apparatus removes liquid from a vacuum tank () with a suction pump () and supplies that liquid to a storage tank (), sprays storage tank liquid into the vacuum tank through a convergent nozzle (), removes gas from liquid in a state of reduced pressure inside the vacuum tank, and stores the degassed liquid in the storage tank. The storage tank is an airtight hermetically sealed tank provided with a reduced pressure retaining valve that discharges gas accumulated inside the storage tank.

Degassing apparatus for removing dissolved gas from liquids

The present invention provides an array-type photo module including a filter, which, in each channel, transmits therethrough a portion of emitted light from an incident optical fiber on the opposite side of a gradient-index lens array and reflects another portion of the emitted light from the incident optical fiber toward the gradient-index lens array, and a light-shielding member which is arranged on the opposite side of the filter from the gradient-index lens array, so as to be spaced from the filter and, in each channel, has an opening passing therethrough transmitted light from the filter on the opposite side of the filter. The array-type photo module is easily and inexpensively manufactured, and may be used in a high-density array, with low crosstalk.

Array-type photo module

An optical module has a structure for reducing the stress applied to a package. The optical module is structured so that an end face of a waveguide () of a planar lightwave circuit () is joined to a plurality of packages () storing therein optical elements so that the waveguide is optically coupled to the optical elements. The optical module includes a housing () storing therein a planar lightwave circuit and a plurality of packages in which an upper face of a protrusion () formed in the bottom section is fixed to the planar lightwave circuit (). Each of the plurality of packages () is electrically connected to an electric part () provided in the housing () via flexible printed circuits ().

Optical module

A packaging platform for optically coupling one or more optical waveguides of one or more optical components having the optical waveguide to one or more optical fibers is provided with a reference structure portion for the horizontal and vertical positioning of the optical component. The platform is further provided with one or more fiber positioning portions for inserting and holding the optical fiber and positioning the optical fiber at a position where the optical fiber is optically connected to the optical waveguide. The provided packaging platform and an optical module using the platform can simplify all alignment steps for optical coupling, electrical connection and sealing in the coupling of the optical component and the optical fiber.

Packaging platform, optical module using the platform, and methods for producing the platform and the module

A plastic ferrule for an optical connector comprises a cylindrical portion having one insertion hole for fixing an optical fiber and directly related to connection, a holding portion for allowing the cylindrical portion to be stably held in an optical connector, and an guiding portion for allowing an optical fiber to be guided into the ferrule. The ferrule has a hollow, cylindrical hole centering around the insertion hole inside the cylindrical portion. Thus, the ferrule has excellent dimensional accuracy of the outer diameter, and achieves connection of single mode fibers excellent in connection reliability and economy.

Plastic ferrule for optical connector and method for production thereof

According to a first aspect of the invention, an optical position sensor employs a position encoder having collimators and reflectors with mutually aligned optical axes mounted in a support. A slotted code plate moves between the collimators and reflectors in a plane non-perpendicular to their optic axes. This encoder converts position to optical signals reliably, regardless of mechanical shock or vibration. According to a second aspect of the invention, an optical position sensing system employs wavelength-division multiplexing to distribute light pulses to different position encoders and time-division multiplexing to further distribute pluses to the collimators in each encoder. This permits multiple position encoders to be served by a single light source and optical fiber.

Wavelength-division multiplex digital optical position sensor

In an optical amplifier, light incident on a first port of a port separator is emitted out of a third port, and is input into and amplified in a semiconductor laser. Amplified light receives the first amount of rotation, e.g., a 45.degree. rotation, of the direction of polarization in a Faraday rotator assembly and is emitted outward. Light emitted out of the Faraday rotator assembly is reflected by the reflector. Passed through the Faraday rotator assembly backward, receives the second amount of rotation, e.g., a further 45.degree. rotation, of the direction of polarization in the same direction as the previous rotation, and is input into the semiconductor laser. The input light is amplified again in the semiconductor laser, is input in the third port of the port separator, and is emitted outward from a second port. The direction of polarization of light passing forward and backward through the semiconductor laser are orthogonal to each other, and therefore amplification will be done at a constant degree of amplification, regardless of the direction of polarization.

Optical amplifier

A fiber input/output type semiconductor optical amplifier module is disclosed. The optical amplifier module of the present invention, a semiconductor laser amplifier chip is provided for direct amplification of signal light beam. An optical coupling between the semiconductor laser chip and an input/output fibers is taken with a remote coupling using a parallel light beam. Collimator lenses are provided for converting the lightwave signal into a parallel light beam. Two optical isolators are provided for preventing a self-lasing of the semiconductor laser chip. One of the isolators is inserted on an input side of the semiconductor laser chip, and the other is inserted on an output side of the chip. An interference filter and a beam splitter are disposed in the output side of the semiconductor laser chip. The beam splitter splits the output signal of the semiconductor laser chip for monitoring an output power of the chip.

Optical amplifier module

A high power pump light source for optical direct amplifier using the stimulated Raman effect is obtained by using a plurality of semiconductor lasers each of which provides low output power. More than two beams of the same wavelength generated by semiconductor lasers are combined (polarization multiplex) by using a polarization prism block, which provides sufficient high power pump light for the stimulated Raman effect amplifier. The output of said polarization prism block is wavelength division multiplexed with signal light to be amplified by using an interference filter block, the output of which is applied to a transmission optical fiber in which amplification of said signal light is effected.

Optical coupler for optical direct amplifier

Growing community of inventors

Tokyo, Japan

Yasuaki Tamura