Patents by Inventor Masahiro Okamura
Masahiro Okamura has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 5504187Abstract: Granules collected from a solution of a polycarbonate, an integrated structure of independent fine particles constituting the granules being formed at least on the surfaces of the granules; and a process for preparing the granules of the polycarbonate which comprises the steps of adding a poor solvent to the polycarbonate solution, and then agitation-granulating fine particles of the polycarbonate into the granules, while stirring involving a shear force-imparting function is carried out under heating. According to the present invention, the polycarbonate or the like can be collected from its organic solvent solution as the granules having good drying properties.Type: GrantFiled: July 26, 1994Date of Patent: April 2, 1996Assignee: Idemitsu Petrochemical Co., Ltd.Inventors: Noriyuki Kunishi, Masahiro Okamura, Takashi Tsukahara, Masahiro Takahashi
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Patent number: 5247126Abstract: In an image reproducing apparatus, a music information reproducing unit reproduces musical information, lyrics information or still picture information from a music information recording medium on which the musical information, the lyrics information or the still picture information relating to a plurality of music pieces are recorded, and an image information reproducing unit retrieves moving picture information in a predetermined order in correspondence with respective music pieces in the music information recording medium from an image information recording medium on which moving picture information divided into a plurality of moving picture information segments is recorded, and reproducing said picture information segments.Type: GrantFiled: November 25, 1991Date of Patent: September 21, 1993Assignee: Pioneer Electric CorporationInventors: Masahiro Okamura, Masuhiro Sato, Naoto Inaba, Yoshiyuki Akiba, Toshiki Nakai
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Patent number: 5235124Abstract: A musical accompaniment playing apparatus comprises a MIDI sound source, a phoneme information memory, a playing information memory, a control means, a mixing means and a sound output means.When a user sings a song with a musical accompaniment and a back chorus, the control means controls the MIDI sound source to output an audio signal in accordance with a phoneme information stored in the phoneme memory and a playing information stored in the playing information memory. The output audio signal is mixed with a singing voice of the user at the mixing means and output from the sound output means as a song in harmony with the back chorus.Type: GrantFiled: April 15, 1992Date of Patent: August 10, 1993Assignee: Pioneer Electronic CorporationInventors: Masahiro Okamura, Masuhiro Sato, Naoto Inaba, Yoshiyuki Akiba, Toshiki Nakai
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Patent number: 5218580Abstract: A user management system is provided for a musical accompaniment playing (KARAOKE) apparatus. The system comprises an individual information recording medium, an input unit, a music information reproducing unit, a control unit and a calculation unit. The input unit is used to input user identification information and music piece selection. The control unit serves to set a musical environment and to record changes in the environment for the user. The calculation unit makes adjustments based on the number of music pieces recorded on the individual information recording medium.Type: GrantFiled: April 9, 1992Date of Patent: June 8, 1993Assignee: Pioneer Electronic CorporationInventors: Masahiro Okamura, Masuhiro Sato, Naoto Inaba, Yoshiyuki Akiba, Toshiki Nakai
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Patent number: 4745088Abstract: The vapor phase growth on semiconductor wafers is carried out by an apparatus in which a multiplicity of semiconductor wafers are held by a holder so that the semiconductor wafers lie one over another in a vertical direction, and are rotated together with the holder, the holder is placed in a heater disposed in a reaction vessel, a raw material gas supply nozzle and a raw material gas exhaust nozzle are provided within the heater so that the semiconductor wafers are interposed between the gas supply nozzle and the gas discharge nozzle, and the gas supply nozzle and the gas discharge nozzle have gas supply holes and gas discharge holes, respectively, so that a raw material gas can flow on each semiconductor wafer in horizontal directions. When the temperature of the heater is raised by a heating source to heat the semiconductor wafers, the raw material gas is supplied from the gas supply holes to each semiconductor wafer, and thus a uniform layer is grown on each semiconductor wafer from the raw material gas.Type: GrantFiled: February 19, 1986Date of Patent: May 17, 1988Assignees: Hitachi, Ltd., Kokusai Elect. Co. Ltd.Inventors: Yosuke Inoue, Takaya Suzuki, Masahiro Okamura, Noboru Akiyama, Masato Fujita, Hiroo Tochikubo, Shinya Iida
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Patent number: 4682199Abstract: In a high-voltage thyristor comprising a semiconductor body having contiguous pnpn four layers, and opposed anode and cathode electrodes and a gate electrode provided for the semiconductor body, one of p-base and n-base regions having an impurity concentration higher than the other has an impurity concentration which is no more than 8.times.10.sup.15 atoms/cm.sup.3 in the vicinity of a junction between the one base region and an adjacent emitter region and which has a gradually decreasing gradient toward the other contiguous base region. The one base region has a sheet resistance of 500 to 1500 ohms/.quadrature.. The realization of a high-voltage, large-diameter and large-current thyristor can be ensured.Type: GrantFiled: April 28, 1983Date of Patent: July 21, 1987Assignee: Hitachi, Ltd.Inventors: Tsutomu Yatsuo, Naohiro Momma, Masayoshi Naito, Masahiro Okamura
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Patent number: 4649990Abstract: A heat-conducting cooling module for cooling a semiconductor substrate in an integrated circuit package assembly in which a semiconductor substrate is mounted on a base board by small solder pellets, and which contains a single substrate or laminated substrates. A heat-conducting relay member is provided between the semiconductor substrate and a housing so as to be pressed onto the semiconductor substrate. At least either one of the housing or the heat-conducting relay member is made of a sintered product which includes silicon carbide as a chief component.Type: GrantFiled: May 6, 1985Date of Patent: March 17, 1987Assignee: Hitachi, Ltd.Inventors: Yasutoshi Kurihara, Tasao Soga, Hiroaki Hachino, Kenji Miyata, Masahiro Okamura, Fumiyuki Kobayashi, Takahiro Daikoku
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Patent number: 4514747Abstract: Disclosed is a field controlled thyristor in which a first semiconductor region of N.sup.+ -type, a second semiconductor region of N-type, third semiconductor regions of P-type, a fourth semiconductor region of N.sup.- -type and a fifth semiconductor region of P.sup.+ -type are formed in a semiconductor substrate having two main surfaces, the first, second and third semiconductor regions being exposed in the first main surface and the fifth semiconductor region being exposed in the second main surface; and the third semiconductor regions of P-type are spaced from each other by a predetermined spacing. The third semiconductor regions are connected with surface-exposed semiconductor regions exposed in the first main surface. The impurity concentration in the second semiconductor region decreases from the first semiconductor region toward the third semiconductor region so that a low forward voltage drop can be achieved along with a high reverse blocking voltage.Type: GrantFiled: March 12, 1982Date of Patent: April 30, 1985Assignee: Hitachi, Ltd.Inventors: Kenji Miyata, Yoshio Terasawa, Saburo Oikawa, Susumu Murakami, Masahiro Okamura
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Patent number: 4491562Abstract: This invention provides a thermal fatigue resistant, low-melting point solder alloy consisting of 13 to 20% by weight Bi, 42 to 50% by weight, Pb, the balance being Sn. This solder alloy is suited for lap joints of electronic parts into or onto a printed substrate or a hybrid substrate.Type: GrantFiled: June 7, 1983Date of Patent: January 1, 1985Assignee: Hitachi, Ltd.Inventors: Tasao Soga, Takaya Suzuki, Masahiro Okamura, Masahiro Gooda, Fumiyuki Kobayashi
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Patent number: 4388635Abstract: A novel structure of a high breakdown voltage semiconductor device has a pair of major surfaces on which a pair of main electrodes are formed and a PN junction formed between the pair of major surfaces with a side surface to which the PN junction is exposed being covered with a passivation material. An auxiliary electrode of a conductive member is provided, which is disposed externally of the peripheral edge of the major surface of the semiconductor substrate, and which contacts to the passivation material and is electrically connected to the main electrode. When a voltage for reverse biasing the PN junction is applied between the pair of main electrodes, ions in the passivation material are collected by an electric field established in the passivation material so that the deterioration of the breakdown on the surface of the semiconductor substrate is prevented.Type: GrantFiled: July 1, 1980Date of Patent: June 14, 1983Assignee: Hitachi, Ltd.Inventors: Atsuo Watanabe, Masayoshi Naito, Tsutomu Yatsuo, Masahiro Okamura
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Patent number: 4354121Abstract: A switching control circuit includes a first field controlled thyristor having a gate and a cathode between which a backward bias voltage source and a second field controlled thyristor are connected in series. Conduction of the second field controlled thyristor is controlled by controlling a voltage applied across the gate and the cathode, thereby to control conduction of the first field controlled thyristor. A large load current can be positively and safely turned on and off by a relatively small control current or voltage.Type: GrantFiled: July 10, 1981Date of Patent: October 12, 1982Assignee: Hitachi, Ltd.Inventors: Yoshio Terasawa, Kenji Miyata, Saburo Oikawa, Susumu Murakami, Masahiro Okamura, Takuzo Ogawa
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Patent number: 4258377Abstract: An improvement in a semiconductor switching device is disclosed which comprises a semiconductor substrate of a first conductivity type, an anode region of a second conductivity type formed in the semiconductor substrate adjacent to a major surface thereof, a gate region of the second conductivity type formed a distance from the anode region, and a cathode region of the first conductivity type formed in the gate region and having a higher impurity concentration than the semiconductor substrate. A channel region is formed immediately below the cathode region thereby to directly contact the cathode region to the semiconductor substrate. A current path extending from the anode region to the cathode region through the semiconductor substrate is interrupted by a depletion layer produced in the vicinity of the channel region upon application of a reverse bias across a pn-junction formed between the gate region and the cathode region.Type: GrantFiled: March 12, 1979Date of Patent: March 24, 1981Assignee: Hitachi, Ltd.Inventors: Kenji Miyata, Tatsuya Kamei, Masahiro Okamura
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Patent number: 4223328Abstract: A field controlled thyristor is disclosed which comprises a first emitter region exposed to one main surface of a semiconductor substrate and having a first conductivity type, a second emitter region exposed to the other main surface of the substrate and having a second conductivity type, a base region connecting the first and the second emitter region, and a gate region provided in the base region. The gate region consists of a slab-like first portion disposed parallel to both the emitter and a second portion connecting the first slab-like portion with one of the main surfaces of the semiconductor substrate. The impurity concentration of the base region is higher in the portion of the base region nearer to the emitter region having the same conductivity type as that of the base region than in the portion of the base region nearer to the emitter region having the opposite conductivity type to that of the base region.Type: GrantFiled: June 1, 1978Date of Patent: September 16, 1980Assignee: Hitachi, Ltd.Inventors: Yoshio Terasawa, Kenji Miyata, Masayoshi Naito, Takuzo Ogawa, Masahiro Okamura
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Patent number: 4216487Abstract: Disclosed is a bidirectional light-activated thyristor which comprises a first and a second thyristor portion arranged in inverse-parallel with each other with a predetermined positional relation, an isolation section for electrically isolating the first and second thyristor portions from each other, a first and a second main electrode for connecting the first and second thyristor portions with each other in inverse-parallel, and a first and a second photo-trigger means for triggering the first and second thyristor portions respectively, wherein the photo-trigger signal from the first photo-trigger means is prevented by the first thyristor portion from reaching the second thyristor portion and the photo-trigger signal from the second photo-trigger means is prevented by the second thyristor portion from reaching the first thyristor portion.Type: GrantFiled: February 21, 1978Date of Patent: August 5, 1980Assignee: Hitachi, Ltd.Inventors: Nobutake Konishi, Takeshi Yokota, Yoshitaka Sugawara, Tsutomu Yatsuo, Masahiro Okamura
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Patent number: 4210464Abstract: The whole body of a semiconductor device with its pn junction exposed ends covered by insulating glass is subjected to the exposure to radiation having an energy of higher than 0.5 MeV in terms of the reduced energy of electron beams while the semiconductor device is maintained at temperatures higher than 300.degree. C., and preferably higher than 350.degree. C. As a result, the life time of the minority carriers in the semiconductor device can be shortened without increasing the leakage current in the reverse direction.Type: GrantFiled: January 31, 1978Date of Patent: July 1, 1980Assignee: Hitachi, Ltd.Inventors: Tomoyuki Tanaka, Masahiro Okamura, Toshikatsu Shirasawa, Takuzo Ogawa
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Patent number: 4201598Abstract: Semiconductor devices with improved reverse characteristics are obtained by exposing the semiconductor bodies of the devices that are passivated by alkali-free glasses to a high energy radiation such as an electron radiation so as to shorten a life time of the bodies down to a predetermined value, while increasing the reverse leakage current of the bodies, and by subjecting the irradiated semiconductor bodies to an annealing treatment at a temperature of 250.degree. to 350.degree. C. for a sufficient time so as to decrease the reverse leakage current down to a predetermined value, while maintaining the order of the shortened life time.Type: GrantFiled: August 1, 1977Date of Patent: May 6, 1980Assignee: Hitachi, Ltd.Inventors: Tomoyuki Tanaka, Toshikatsu Shirasawa, Masahiro Okamura
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Patent number: 4110781Abstract: A bidirectional light-activated thyristor is provided which has a first and a second thyristor portion arranged in inverse-parallel with each other with a predetermined positional relation. The first and second thyristor portions are electrically isolated from each other by an isolating section. The bidirectional light-activated thyristor is provided with a first and a second photo trigger means for triggering the first and second thyristor portions respectively. Means is further provided for blocking a photo-trigger signal from the first photo-trigger means to the second thyristor portion and from the second photo-trigger means to the first thyristor portion.Type: GrantFiled: October 5, 1976Date of Patent: August 29, 1978Assignee: Hitachi, Ltd.Inventors: Nobutake Konishi, Takeshi Yokota, Yoshitaka Sugawara, Tsutomu Yatsuo, Masahiro Okamura
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Patent number: 4083062Abstract: An avalanche photodiode has a rectification barrier formed by an n.sup.+ -layer and a p-type layer of a low doping concentration. A thin p-layer having a higher doping concentration than a p.sup.- -layer is inserted between the p.sup.- -layer and a .pi.-layer, whereby the avalanche breakdown voltage of the photodiode is lowered considerably.Type: GrantFiled: February 8, 1977Date of Patent: April 4, 1978Assignee: Hitachi, Ltd.Inventors: Hirobumi Ohuchi, Sumio Kawakami, Masahiro Okamura
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Patent number: 4079405Abstract: A semiconductor photodetector comprising a first semiconductor layer having N-type conductivity; a second semiconductor layer having N-type conductivity, disposed in the vicinity of the first semiconductor layer and having a resistivity higher than that of the first semiconductor layer; a third region having P-type conductivity, disposed in the vicinity of the second semiconductor layer and having a thickness smaller than that of the second semiconductor layer; a first main electrode kept in ohmic contact with the first semiconductor layer; and a second main electrode kept in ohmic contact with a portion of the third region, the surface of the third region serving as a light receiving surface.Type: GrantFiled: June 24, 1975Date of Patent: March 14, 1978Assignee: Hitachi, Ltd.Inventors: Hirobumi Ohuchi, Masahiro Okamura, Sumio Kawakami, Takuzo Ogawa
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Patent number: 4040084Abstract: A semiconductor device having a high blocking voltage, comprises a pair of principal surfaces opposite to each other, a circular groove cut in the peripheral portion of one of the principal surfaces and a PN junction formed along the surface of the groove and the one of the principal surfaces, wherein the region on the side of the PN junction near the one of the principal surfaces is of high impurity concentration, the outer edge of the PN junction appears in the bevel surface connecting the pair of principal surfaces, and the edge of the PN junction intersects the bevel surface in such a manner that the angle therebetween in the region of high impurity concentration is obtuse.Type: GrantFiled: September 5, 1975Date of Patent: August 2, 1977Assignee: Hitachi, Ltd.Inventors: Tomoyuki Tanaka, Masahiro Okamura, Takuzo Ogawa, Yutaka Misawa