Patents by Inventor Tadashi Okumura
Tadashi Okumura 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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Publication number: 20230198228Abstract: An edge-emitting multi-beam semiconductor laser device includes a layered structure including a substrate, an n-type cladding layer, a light-emitting layer, and a p-type cladding layer. The layered structure has m regions (m?2) that are adjacent in a first direction, and a sum of a height of the substrate and a height of the first conductive cladding layer is different in each of the m regions, n laser resonators (2?n?m) each having a ridge stripe structure extending in a second direction orthogonal to the first direction are formed in the n regions among the m regions, and at least two of the n laser resonators have different oscillation wavelengths among the n laser resonators.Type: ApplicationFiled: December 11, 2022Publication date: June 22, 2023Applicant: Ushio Denki Kabushiki KaishaInventors: Tadashi Okumura, Shigeta Sakai
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Patent number: 11423299Abstract: A device includes an input unit, a nonlinear converter, and an output unit. The nonlinear converter and the output unit are connected via a connection path having a delay mechanism that realizes a feedback loop giving a delay to a signal. The delay mechanism includes a conversion mechanism that generates a plurality of signals with different delay times using the signal output from the nonlinear converter, generates a new signal by superimposing the plurality of signals, and outputs the generated signal to the output unit.Type: GrantFiled: November 29, 2018Date of Patent: August 23, 2022Assignee: Hitachi, Ltd.Inventors: Tadashi Okumura, Mitsuharu Tai, Masahiko Ando, Sanato Nagata, Norifumi Kameshiro
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Patent number: 11423286Abstract: A technology that can enhance the computing performance of a computing system using reservoir computing (RC), includes a computing system which performs computation using a recurrent neural network (RNN) including an input unit, a reservoir unit, and an output unit. The reservoir unit includes a plurality of nodes circularly connected to each other. The circular connection has a weight matrix for determining a weight between the nodes of the plurality of nodes, in which a weight between the nodes closely arranged on the circle is larger than a weight between the nodes arranged away from each other on the circle. The plurality of nodes each have a g value that is a parameter for designating nonlinearity of an activation function of each of the nodes, and that is set so as to periodically change in a direction on the circle.Type: GrantFiled: May 29, 2020Date of Patent: August 23, 2022Assignee: HITACHI, LTD.Inventors: Sanato Nagata, Tadashi Okumura, Masahiko Ando
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Publication number: 20220209508Abstract: A semiconductor laser device includes: a substrate having a main surface; a first cladding layer with a first conductive type and a second cladding layer with a second conductive type, which are stacked over the main surface of the substrate; and a light-emitting layer that is formed between the first cladding layer and the second cladding layer, and is formed on a first surface parallel to the main surface of the substrate; the light-emitting layer has a plurality of light-emitting regions emitting laser beams in a red range; and among the laser beams emitted from the light-emitting regions, the difference between a peak wavelength in an optical spectrum of at least one laser beam and a peak wavelength in an optical spectrum of the other laser beams is 1.5 nm or more.Type: ApplicationFiled: December 22, 2021Publication date: June 30, 2022Applicant: Ushio Denki Kabushiki KaishaInventors: Masato Hagimoto, Tadashi Okumura, Yutaka Inoue
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Publication number: 20220209507Abstract: A semiconductor laser device includes: a substrate having a main surface; a first cladding layer with a first conductive type and a second cladding layer with a second conductive type different from the first conductive type, which are stacked over the main surface of the substrate; and a light-emitting layer that is formed between the first cladding layer and the second cladding layer, and is formed on a first surface parallel to the main surface of the substrate; the light-emitting layer has a plurality of light-emitting regions emitting laser beams in a red range; and values of peak wavelengths in an optical spectrum of the laser beams, which are emitted from the light-emitting regions, are different in accordance with the thickness of the light-emitting layer from the first surface.Type: ApplicationFiled: December 22, 2021Publication date: June 30, 2022Applicant: Ushio Denki Kabushiki KaishaInventors: Yutaka Inoue, Masato Hagimoto, Tadashi Okumura
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Publication number: 20210049462Abstract: Provided is a computer system for generating a neural network (NN) used for a task including a training unit that calculates a weighting factor between a reservoir and an output layer using training data, a first storage unit that stores, as node activity information, information on a node activity level of a node included in the reservoir, and a second storage unit that stores model information. When receiving a training execution request for a second task after a training process of a first task is completed, the training unit calculates a weighting factor of the NN used for a third task obtained by combining the first task and the second task, updates the model information based on the calculated weighting factor, and updates the node activity information based on the node activity measured during execution of the training process of the third task.Type: ApplicationFiled: July 27, 2020Publication date: February 18, 2021Inventors: Tadashi OKUMURA, Sanato NAGATA, Masahiko ANDO
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Publication number: 20200387775Abstract: A technology that can enhance the computing performance of a computing system using reservoir computing (RC), includes a computing system which performs computation using a recurrent neural network (RNN) including an input unit, a reservoir unit, and an output unit. The reservoir unit includes a plurality of nodes circularly connected to each other. The circular connection has a weight matrix for determining a weight between the nodes of the plurality of nodes, in which a weight between the nodes closely arranged on the circle is larger than a weight between the nodes arranged away from each other on the circle. The plurality of nodes each have a g value that is a parameter for designating nonlinearity of an activation function of each of the nodes, and that is set so as to periodically change in a direction on the circle.Type: ApplicationFiled: May 29, 2020Publication date: December 10, 2020Applicant: HITACHI, LTD.Inventors: Sanato NAGATA, Tadashi OKUMURA, Masahiko ANDO
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Publication number: 20200334516Abstract: A computer generates a model for outputting an output value on the basis of a plurality of pieces of time-series data having different data types. The model includes a network that is for hied of connections of nodes having a recursive structure and updates states of the nodes according to a predetermined time step, and an adder that calculates the output value. The computer comprises: a learning unit configured to execute, for each of a plurality of output values, a learning process of calculating weight data including the plurality of weights by using learning data and a first storing unit configured to store a plurality of learning results each of which correlates a type of the output value and the weight data with each other.Type: ApplicationFiled: March 13, 2020Publication date: October 22, 2020Applicant: HITACHI, LTD.Inventors: Mitsuharu TAI, Jun FURUYA, Nobuhiro FUKUDA, Tadashi OKUMURA, Masahiko ANDO
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Publication number: 20190227044Abstract: An artificial olfactory sensing system includes a sensor unit. The sensor unit includes a semiconductor device equipped with a transistor and a sensor cell in which an olfactory receptor is manifested on a lipid film. A proton adsorption film is formed on a gate electrode of the transistor. A physiological aqueous solution is disposed on the proton adsorption film. Then, the sensor cell is disposed in the physiological aqueous solution. A proton is adsorbed onto the proton adsorption film. When the olfactory receptor recognizes an odor molecule, the positive ions in the physiological aqueous solution flow from an ion channel of the olfactory receptor into the sensor cell. As a result, the proton is dissociated from the proton adsorption film into the physiological aqueous solution, and the potential of the gate electrode is changed.Type: ApplicationFiled: January 17, 2019Publication date: July 25, 2019Inventors: Masahiko ANDO, Norifumi KAMESHIRO, Tadashi OKUMURA, Sanato NAGATA, Ryohei KANZAKI, Daigo TERUTSUKI, Hidefumi MITSUNO, Takeshi SAKURAI
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Publication number: 20190164053Abstract: A device includes an input unit, a nonlinear converter, and an output unit. The nonlinear converter and the output unit are connected via a connection path having a delay mechanism that realizes a feedback loop giving a delay to a signal. The delay mechanism includes a conversion mechanism that generates a plurality of signals with different delay times using the signal output from the nonlinear converter, generates a new signal by superimposing the plurality of signals, and outputs the generated signal to the output unit.Type: ApplicationFiled: November 29, 2018Publication date: May 30, 2019Inventors: Tadashi OKUMURA, Mitsuharu TAI, Masahiko ANDO, Sanato NAGATA, Norifumi KAMESHIRO
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Publication number: 20180293495Abstract: A computer system that executes computation processing using a recurrent neural network constituted with an input unit, a reservoir unit, and an output unit. The input unit includes an input node that receives a plurality of time-series data, the reservoir unit includes a nonlinear node accompanying time delay, the output unit includes an output node calculating an output value. The input unit calculates a plurality of input streams by executing sample and hold processing and mask processing on a plurality of received time-series data, executes time shift processing that gives deviation in time to each of the plurality of input streams and superimposes the plurality of input streams subjected to the time shift processing, thereby calculating input data.Type: ApplicationFiled: February 21, 2018Publication date: October 11, 2018Inventors: Tadashi OKUMURA, Mitsuharu TAl, Hiromasa TAKAHASHI, Masahiko ANDO, Norifumi KAMESHIRO, Sanato NAGATA
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Patent number: 9664866Abstract: An optical transmission module in which optical axis adjustment is possible in a wide range and with a high accuracy, and a method of manufacturing the optical transmission module are provided. An optical transmission module includes a light source that outputs light, a mirror that reflects the light output by the light source, a lever on which the mirror is arranged and that has a fulcrum, a lens that converges the light reflected by the mirror, and a waveguide that transfers the light converged by the lens, with a core having a section width smaller than a wavelength in vacuum of the light.Type: GrantFiled: October 11, 2016Date of Patent: May 30, 2017Assignee: OCLARO JAPAN, INC.Inventor: Tadashi Okumura
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Publication number: 20170031114Abstract: An optical transmission module in which optical axis adjustment is possible in a wide range and with a high accuracy, and a method of manufacturing the optical transmission module are provided. An optical transmission module includes a light source that outputs light, a mirror that reflects the light output by the light source, a lever on which the mirror is arranged and that has a fulcrum, a lens that converges the light reflected by the mirror, and a waveguide that transfers the light converged by the lens, with a core having a section width smaller than a wavelength in vacuum of the light.Type: ApplicationFiled: October 11, 2016Publication date: February 2, 2017Inventor: Tadashi OKUMURA
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Patent number: 9523825Abstract: An optical transmission module in which optical axis adjustment is possible in a wide range and with a high accuracy, and a method of manufacturing the optical transmission module are provided. An optical transmission module includes a light source that outputs light, a mirror that reflects the light output by the light source, a lever on which the mirror is arranged and that has a fulcrum, a lens that converges the light reflected by the mirror, and a waveguide that transfers the light converged by the lens, with a core having a section width smaller than a wavelength in vacuum of the light.Type: GrantFiled: December 3, 2015Date of Patent: December 20, 2016Assignee: OCLARO JAPAN, INC.Inventor: Tadashi Okumura
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Publication number: 20160170159Abstract: An optical transmission module in which optical axis adjustment is possible in a wide range and with a high accuracy, and a method of manufacturing the optical transmission module are provided. An optical transmission module includes a light source that outputs light, a mirror that reflects the light output by the light source, a lever on which the mirror is arranged and that has a fulcrum, a lens that converges the light reflected by the mirror, and a waveguide that transfers the light converged by the lens, with a core having a section width smaller than a wavelength in vacuum of the light.Type: ApplicationFiled: December 3, 2015Publication date: June 16, 2016Inventor: Tadashi OKUMURA
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Patent number: 9269869Abstract: In order to provide a highly reliable silicon-germanium semiconductor optical element of high luminous efficiency or of low power consumption that can reduce or prevent the occurrence of dislocations or crystal defects on the interface between a light emitting layer or a light absorption layer and a cladding layer, in a silicon-germanium semiconductor optical element, a germanium protective layer 11 of non-light emission is disposed between a germanium light emitting layer or the light absorption layer 10 and a cladding layer 12 disposed above a substrate. The germanium protective layer 11 has the electrical conductivity different from electrical conductivity of the germanium light emitting layer or the light absorption layer 10.Type: GrantFiled: December 12, 2011Date of Patent: February 23, 2016Assignee: Hitachi, Ltd.Inventors: Tadashi Okumura, Shinichi Saito, Kazuki Tani, Etsuko Nomoto, Katsuya Oda
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Patent number: 9032773Abstract: [Problem] To present a manufacturing apparatus of a plate-like tooth profile member capable of forging and forming in one process by using a closed type die, being hardly accompanied by burrs due to plastic changes in the circumferential direction and in the axial direction of the material of the plate-like tooth profile member.Type: GrantFiled: November 19, 2010Date of Patent: May 19, 2015Assignee: Gohsyu CorporationInventors: Tadashi Okumura, Nobuyasu Nishihata, Kenji Tasaki
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Publication number: 20140355636Abstract: In order to provide a highly reliable silicon-germanium semiconductor optical element of high luminous efficiency or of low power consumption that can reduce or prevent the occurrence of dislocations or crystal defects on the interface between a light emitting layer or a light absorption layer and a cladding layer, in a silicon-germanium semiconductor optical element, a germanium protective layer 11 of non-light emission is disposed between a germanium light emitting layer or the light absorption layer 10 and a cladding layer 12 disposed above a substrate. The germanium protective layer 11 has the electrical conductivity different from electrical conductivity of the germanium light emitting layer or the light absorption layer 10.Type: ApplicationFiled: December 12, 2011Publication date: December 4, 2014Inventors: Tadashi Okumura, Shinichi Saito, Kazuki Tani, Etsuko Nomoto, Katsuya Oda
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Publication number: 20120247172Abstract: To present a manufacturing apparatus of a plate-like tooth profile member capable of forging and forming in one process by using a closed type die, being hardly accompanied by burrs due to plastic changes in the circumferential direction and in the axial direction of the material of the plate-like tooth profile member.Type: ApplicationFiled: November 19, 2010Publication date: October 4, 2012Inventors: Tadashi Okumura, Nobuyasu Nishihata, Kenji Tasaki
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Patent number: 7628539Abstract: Embodiments of the invention are directed to keeping a height of a pivot bearing low in order to build a thinner magnetic disk drive. In one embodiment, a ball bearing is provided between a shaft and a sleeve. An inner race of the ball bearing is secured to the shaft through bonding or the like. An outer race of the ball bearing is secured to the sleeve through bonding or the like. A bearing ball is placed between the inner race and the outer race of the ball bearing. A magnet is fitted to the outer race of the ball bearing. A magnet is mounted on a circular plate mounted on one end of the shaft. The magnet is located at a position opposing the magnet mounted on the outer race so as to generate a repulsive force therebetween.Type: GrantFiled: October 6, 2005Date of Patent: December 8, 2009Assignee: Hitachi Global Storage Technologies Netherlands B.V.Inventor: Tadashi Okumura