Hamamatsu-photonics K.k.

Ricoh Company, Ltd.

Kyocera Corporation

Nippon Telegraph and Telephone Corporation

Mikio Kyomasu

Masaki Hirose

Seiichiro Mizuno

Yoshihisa Warashina

Masahiro Shindo

Haruhiko Ichino

Shinobu Fukunaga

Toshiyuki Araki

Michiaki Hiraoka

Koji Takemura

Toshimichi Yasuda

Masanori Sahara

Toshihiro Takimoto

Satoshi Kono

Shiro Sakushima

Hideto Sonoda

Akira Kashiwazaki

Kenichi Okajima

Hiroyasu Nakamura

Takashi Yamagishi

Shin Ikegami

Takeshi Ikeya

Sadaaki Minamimoto

Koshi Nomura

Hiroshi Hashimoto

Hitoshi Tanaka

An optical device having: an optical fiber body; a ferrule which surrounds the above described optical fiber body and to which a recess that crosses a coreless fiber within the above described optical fiber has been provided; and an optical element which is provided within the recess in said ferrule, is provided with a protective member for protecting the above described recess, and the protective member has a restriction means for physically restricting the rotation of the optical device around the optical axis.

Optical device

On one principal plane of a silicon substrate,, a silicon oxide film,having an opening,is formed, and a silicon nitride film,having an opening,overlapping the opening,and a recessed marker,is stacked on the silicon oxide film,. Next, the substrate,is etched through the openings,to provide an alignment groove,for an optical waveguide, and an electrode pattern,is formed. Light of which wavelength transmits through the substrate,and the silicon oxide film,is radiated from the other principal plane of the substrate,, and the optical element is assembled with the marker,serving as the reference while the marker,and the optical element are monitored.

Optical device and its production method

A light emitting unit including a light emitting device of a light emitting module for optical communication is constituted by a laser diode for emitting communication light, a sub-mount having a good thermal conductivity and holding the laser diode on its upper surface, a heat sink for removing the heat generated by the laser diode, a photodiode for monitoring a light output from the laser diode, a laser driver IC which is thermally isolated from the laser diode, has an electric contact placed near the electric contact of the laser diode and connected thereto by wire bonding, and drives the laser diode, and a metal package for holding the heat sink, the photodiode, and the laser driver IC. A light emitting module for optical communication uses the light emitting unit.

Light transmitting module for optical communication and light

A photodetector unit for a photodetector module for optical communication includes a photodetector circuit unit constituted by a ceramic board on which a photodiode for converting input light into an electrical signal and a preamplifier IC connected to the photodiode by bump bonding are mounted, and which has a photodetector circuit connected to the preamplifier IC by bump bonding, and a main amplification circuit unit constituted by a ceramic board on which a main amplification IC is mounted, and which has a main amplification circuit connected to the main amplification IC by bump bonding. The ceramic boards of the photodetector circuit unit and the main amplification circuit unit are mechanically and electrically connected to each other such that a mount surface of the preamplifier IC becomes perpendicular to a mount surface of the main amplification IC.

Light receiving module for optical communication and light receiving

This receptacle comprises a case made of resin, holding a rigid sleeve by being in contact with the outer wall of the rigid sleeve, having a through hole communicating with the through hole of the rigid sleeve at one end thereof.

Receptacle and method of manufacturing the same

The plurality of functioning circuits are formed in a plurality of P-type well regions formed on a remaining part of said low concentration N-type layer, by isolating from each other. According to the present invention, the photoelectric current from the PIN photodiode can be processed in the functioning circuits formed in the P-type well regions by isolating from each other, so that the interference between the functioning circuits can be prevented and also the shift of the current flowing in each functioning circuit due to the impossibility of the high concentration N-type semiconductor layer to be grounded can be prevented. Therefore, the malfunction of the integrated PIN photodiode sensor can be prevented, and the PIN photodiode sensor can operate with high speed because the distributed resistance between the functioning circuits is decreased.

Optical semiconductor device

This invention relates to a monolithic IC having a PIN photodiode and an n-p-n bipolar transistor formed on a single semiconductor (silicon) substrate. In fabricating such IC, it is important to electrically isolate the photodiode and the bipolar transistor. In addition it is necessary to make the surface of the substrate flat. According to this invention, the inter-device isolation between the above-described two devices is attained by forming two epitaxial layers on the silicon substrate, forming trenches in the layers, and burying silicon dioxide in the trenches. In the monolithic IC according to this invention wiring capacity is small, and high-speed performance becomes possible. A p-type buried-layer is formed below the bipolar transistor to thereby prevent punch through between the bipolar transistor and other devices. Also this invention provides the process for fabricating a planar type bipolar transistor suitable to fabricate the monolithic IC and also provides a PIN photodiode of a new structure.

Monolithic IC having pin photodiode and an electrically active element

An image sensor particularly suitable for use in an autofocus camera includes a light measuring means, a capacitance element for accumulating picture element information which is photoelectrically converted by the light measuring means, a source follower circuit that outputs as picture element information the voltage across the capacitance element with low output impedance, a switching element for reading out the picture element information from the source follower to a video line, and a load element for outputting the output voltage of the source follower to a monitor line. The output voltage from the source follower to the monitor line is compared with a reference voltage which has been preset to a desired output voltage level. The light measuring operation of the light measuring means is caused to stop when the output voltage of the source follower is equal to the reference voltage thereby storing and maintaining across the capacitance element the picture element information which has the desired voltage level.

Image sensor with non-destructive readout

A solid state image sensor in which the charge accumulation period of each picture element can be set at the same point of time. Additionally, the lenngth of the charge period can be set at will, thus providing a video signal picture in which all picture elements bear image information with the same time reference. Sensitivity of the solid state image senosr can be adjusted by setting the length of charge accumulation period. In the solid state image sensor, photodiodes are disposed as picture elements, and video signal is output in accordance with a charge which is light-generated within respective photodiodes. A series circuit of a switch and a capacitance element is connected in parallel with the photodiode. The switch is closed for at least the charge accumulation period during which charge is light-generated within the photodiode, and the video signal is obtained in accordance with level of charging of said capacitance element.

Solid state image sensor having variable charge accumulation time period

A programmable logic array includes a plurality of semiconductor memory elements, such as FAMOSs, arranged in the form of an array and a sense circuit for receiving data out from the memory elements during read out mode. The present programmable logic array is so structured that the sense circuit is rendered operative for a predetermined time period every time when an input signal to the array changes its state thereby allowing to minimize the power consumption.

Programmable logic array having an on/off sense function

A semiconductor memory device is provided with a memory region including SAMOS type memory transistors and a non-memory or peripheral region including MOS transistors which are interconnected to form logic circuits such as decoders for controlling the operation of each of said memory transistors. Each of the transistors includes a pair of first and second doped polysilicon layers and an interlayer insulating film provided as sandwiched between the pair of first and second doped polysilicon layers. In the memory region, the first and second doped polysilicon layers define floating and control gate electrodes, respectively; whereas, in the non-memory region, the first and second doped polysilicon layers are electrically interconnected by a through-the-layer electrode formed through the interlayer insulating film.

Method of making a memory device with polysilicon electrodes

An input buffer circuit comprised of MOS transistors includes an input terminal for receiving a tri-state input signal capable of taking any one of three potential levels, such as V.sub.pp, V.sub.cc and V.sub.ss. The input buffer circuit also includes a first detecting circuit having a first threshold level located between V.sub.pp and V.sub.cc and a second detecting circuit having a second threshold level located between V.sub.cc and V.sub.ss. Also provided is a third detecting circuit connected to the first and second detecting circuits to determine the level of the input signal applied to the input terminal.

Input buffer circuit

An erasable field programmable logic array including a matrix of reprogrammable memory elements which may be selectively programmed to store a desired logic function therein is provided. Since use is made of reprogrammable memory elements, the stored logic function may be erased and another logic function may be programmed into the programmable logic array.

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Hamamatsu, Japan

Mikio Kyomasu