Patents by Inventor Hirokazu Itoh
Hirokazu Itoh 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: 20230187906Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The optical semiconductor device is applied to a ridge-stripe type laser.Type: ApplicationFiled: February 3, 2023Publication date: June 15, 2023Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA
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Patent number: 11605935Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The optical semiconductor device is applied to a ridge-stripe type laser.Type: GrantFiled: February 26, 2021Date of Patent: March 14, 2023Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura
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Patent number: 11581706Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The quantum well active layer is doped with 0.3 to 1×1018/cm3 of n-type impurity.Type: GrantFiled: February 26, 2021Date of Patent: February 14, 2023Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura
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Publication number: 20210210929Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The optical semiconductor device is applied to a ridge-stripe type laser.Type: ApplicationFiled: February 26, 2021Publication date: July 8, 2021Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA
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Publication number: 20210184436Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The optical semiconductor device includes a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer. The optical semiconductor device further includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The quantum well active layer is doped with 0.3 to 1×1018/cm3 of n-type impurity.Type: ApplicationFiled: February 26, 2021Publication date: June 17, 2021Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA
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Patent number: 10938183Abstract: A distributed feedback (DFB) laser outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The DFB laser includes a separate confinement heterostructure layer positioned between the quantum well active layer and then-type cladding layer. The DFB laser includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and then-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The DFB laser has a function to select a specific wavelength by returning a specific wavelength in the wavelength-variable laser.Type: GrantFiled: November 1, 2019Date of Patent: March 2, 2021Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura, Masaki Funabashi, Nobumasa Tanaka
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Publication number: 20200067279Abstract: A distributed feedback (DFB) laser outputting a predetermined wavelength of laser light includes a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction. The DFB laser includes a separate confinement heterostructure layer positioned between the quantum well active layer and then-type cladding layer. The DFB laser includes an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and then-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer. The DFB laser has a function to select a specific wavelength by returning a specific wavelength in the wavelength-variable laser.Type: ApplicationFiled: November 1, 2019Publication date: February 27, 2020Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA, Masaki FUNABASHI, Nobumasa TANAKA
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Patent number: 10511150Abstract: A wavelength-variable laser outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: GrantFiled: July 6, 2018Date of Patent: December 17, 2019Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura, Masaki Funabashi, Nobumasa Tanaka
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Publication number: 20180331503Abstract: A wavelength-variable laser outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: ApplicationFiled: July 6, 2018Publication date: November 15, 2018Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA, Masaki FUNABASHI, Nobumasa TANAKA
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Patent number: 10020638Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: GrantFiled: March 9, 2017Date of Patent: July 10, 2018Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura
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Publication number: 20170187168Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: ApplicationFiled: March 9, 2017Publication date: June 29, 2017Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA
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Patent number: 9601905Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: GrantFiled: July 9, 2015Date of Patent: March 21, 2017Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura
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Publication number: 20150311676Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: ApplicationFiled: July 9, 2015Publication date: October 29, 2015Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA
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Patent number: 9083150Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: GrantFiled: October 6, 2014Date of Patent: July 14, 2015Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji Yoshida, Hirokazu Itoh, Satoshi Irino, Yuichiro Irie, Taketsugu Sawamura
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Publication number: 20150103858Abstract: An optical semiconductor device outputting a predetermined wavelength of laser light includes: a quantum well active layer positioned between a p-type cladding layer and an n-type cladding layer in thickness direction; a separate confinement heterostructure layer positioned between the quantum well active layer and the n-type cladding layer; and an electric-field-distribution-control layer positioned between the separate confinement heterostructure layer and the n-type cladding layer and configured by at least two semiconductor layers having band gap energy greater than band gap energy of a barrier layer constituting the quantum well active layer.Type: ApplicationFiled: October 6, 2014Publication date: April 16, 2015Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Junji YOSHIDA, Hirokazu ITOH, Satoshi IRINO, Yuichiro IRIE, Taketsugu SAWAMURA
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Patent number: 8678769Abstract: A compressor impeller and a method of manufacturing the compressor impeller. The magnesium alloy compressor impeller as a die-cast part comprises a hub shaft part, a hub disk part having a hub surface extending from the hub shaft part in the radial direction, and a plurality of vane parts disposed on the hub surface. The impeller can be manufactured by a die-cast method in which a magnesium alloy heated to a liquidus temperature or higher is supplied into molds with cavities corresponding to the shape of the impeller for a filling time of 1 sec. or shorter, a pressure of 20 MPa or higher is applied to the magnesium alloy in the cavities, and the pressurized state is maintained for a time of 1 sec. or longer.Type: GrantFiled: February 21, 2006Date of Patent: March 25, 2014Assignees: Hitachi Metals Precision, Ltd., Hitachi Metals, Ltd.Inventors: Yasuhiro Kubota, Hirokazu Itoh, Mikio Sasaki
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Patent number: 8385379Abstract: A semiconductor device of the invention is formed so that n-type InP current blocking layers enter the inside of p-type InP cladding layers, i.e., the n-type current blocking layers ride over the upper part of the p-type InP cladding layers, so that a distance between the n-type InP current block layers composing a current blocking region is narrower than a width of the p-type cladding layers contacting with the n-type InP current blocking layers. Thereby, the semiconductor device whose leak current in the current blocking region may be reduced which permits high-output and high-temperature operations may be readily fabricated.Type: GrantFiled: January 7, 2010Date of Patent: February 26, 2013Assignee: Furukawa Electric Co., LtdInventors: Junji Yoshida, Naoki Tsukiji, Hidehiro Taniguchi, Satoshi Irino, Hirokazu Itoh, Harunobu Ikeda, Masako Kobayakawa, Akihiko Kasukawa
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Publication number: 20110164641Abstract: A semiconductor device of the invention is formed so that n-type InP current blocking layers enter the inside of p-type InP cladding layers, i.e., the n-type current blocking layers ride over the upper part of the p-type InP cladding layers, so that a distance between the n-type InP current block layers composing a current blocking region is narrower than a width of the p-type cladding layers contacting with the n-type InP current blocking layers. Thereby, the semiconductor device whose leak current in the current blocking region may be reduced which permits high-output and high-temperature operations may be readily fabricated.Type: ApplicationFiled: January 7, 2010Publication date: July 7, 2011Applicant: Furukawa Electric Co., Ltd.Inventors: Junji Yoshida, Naoki Tsukiji, Hidehiro Taniguchi, Satoshi Irino, Hirokazu Itoh, Harunobu Ikeda, Masako Kobayakawa, Akihiko Kasukawa
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Publication number: 20110064959Abstract: This object relates to a leather which is obtained by forming a coating film through the greasing step following re-tanning and dyeing and the drying step. The purpose of this object is to provide a leather, wherein the generation of free formaldehyde and acetaldehyde is inhibited, an automobile interior part using this leather and a back sizing agent for natural leather to be used for producing the above-described leather.Type: ApplicationFiled: December 26, 2008Publication date: March 17, 2011Applicant: MIDORI HOKUYO CO., LTD.Inventors: Hirokazu Itoh, Keizo Kobayashi, Naoko Abe, Masahiko Sugimoto
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Patent number: 7669637Abstract: A lost-wax cast impeller for a supercharger having no parting line on a hub surface and a blade surface in each space demarcated by pairs of long blades adjacent to each other and having excellent aerodynamic performance. A method of manufacturing the impeller involves forming a lost form pattern in substantially the same shape as the impeller, forming a mold by eliminating the lost form pattern after the lost form pattern is coated with a refractory, and pouring a molten metal in the mold for casting. In the molding step, lost material is injection-molded in a space demarcated by radially arranging, toward a center shaft, a plurality of slide molds having short blade-shaped bottomed groove parts and space shapes between the pairs of long blades adjacent to each other, and the slide molds are released by moving in the radial direction of the center shaft while rotating.Type: GrantFiled: March 30, 2005Date of Patent: March 2, 2010Assignees: Hitachi Metals Ltd., Hitachi Metals Precision, Ltd.Inventors: Yasuhiro Kubota, Hirokazu Itoh