Patents by Inventor Taketsugu SAWAMURA
Taketsugu SAWAMURA 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: 20220317392Abstract: An optical device includes: a case; a sleeve attached to the case, the sleeve including a first through-hole penetrating between an inside and an outside of the case, and an inclined surface inclined with respect to a penetrating direction of the first through-hole, the inclined surface having an opening of the first through-hole; a first optical fiber including a core wire including a core and a clad, and a sheath configured to surround the core wire, wherein an exposed portion of the core wire not surrounded by the sheath passes through the first through-hole; and a first joining material interposed and sealed between an outer peripheral surface of the exposed portion and an inner peripheral surface of the first through-hole in the first through-hole.Type: ApplicationFiled: June 21, 2022Publication date: October 6, 2022Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Atsushi IZAWA, Jun MIYOKAWA, Maiko ARIGA, Kazuya NAGASHIMA, Yozo ISHIKAWA, 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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Patent number: 9711945Abstract: A method of designing a semiconductor laser device includes: controlling a distance between the output-side reflection unit and the second reflection unit and an effective optical feedback ? to the semiconductor laser element, the effective optical feedback ? defined by a below-presented formula (1) including a circulating time ? of the light in the semiconductor laser element, a reflectivity R1 of the output-side reflection unit, and a reflectivity R2 of the second reflection unit; selecting a semiconductor laser device in which an LFF period is equal to or smaller than 20 ns as a semiconductor laser device in which high speed switching occurs between an FBG mode and an FP mode; and using the selected semiconductor laser device as an semiconductor laser device oscillating in a coherent collapse mode.Type: GrantFiled: June 8, 2016Date of Patent: July 18, 2017Assignee: FURUKAWA ELECTRIC CO., LTD.Inventors: Hideaki Hasegawa, Noriyuki Yokouchi, Taketsugu Sawamura, Satoshi Irino, Junji Yoshida
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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: 20160285237Abstract: A method of designing a semiconductor laser device includes: controlling a distance between the output-side reflection unit and the second reflection unit and an effective optical feedback ? to the semiconductor laser element, the effective optical feedback ? defined by a below-presented formula (1) including a circulating time ? of the light in the semiconductor laser element, a reflectivity R1 of the output-side reflection unit, and a reflectivity R2 of the second reflection unit; selecting a semiconductor laser device in which an LFF period is equal to or smaller than 20 ns as a semiconductor laser device in which high speed switching occurs between an FBG mode and an FP mode; and using the selected semiconductor laser device as an semiconductor laser device oscillating in a coherent collapse mode.Type: ApplicationFiled: June 8, 2016Publication date: September 29, 2016Applicant: FURUKAWA ELECTRIC CO., LTD.Inventors: Hideaki HASEGAWA, Noriyuki YOKOUCHI, Taketsugu SAWAMURA, Satoshi IRINO, Junji YOSHIDA
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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