Patents by Inventor Jun Kinugasa
Jun Kinugasa 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).
-
Publication number: 20230152514Abstract: A gain flattening filter includes a first optical fiber that has a core, a first cladding, and a second cladding and that has a uniform composition in a length direction; and a pair of second optical fibers fused to both ends of the first optical fiber. The first optical fiber has a first section in which a slanted refractive index grating is formed and a pair of second sections connecting both ends of the first section to the pair of second optical fibers. The first cladding contains a photosensitive material whose refractive index increases upon irradiation with light having a specific wavelength. In the core, a tensile stress remains in the first section. An average MFD of the second sections is larger than an average MFD of the second optical fibers and smaller than an average MFD of the first section.Type: ApplicationFiled: April 5, 2021Publication date: May 18, 2023Applicants: SUMITOMO ELECTRIC INDUSTRIES, LTD., SUMITOMO ELECTRIC OPTIFRONTIER CO., LTD.Inventors: Shigehiro NAGANO, Takemi HASEGAWA, Jun KINUGASA, Kazuaki MASUI
-
Patent number: 11448821Abstract: One embodiment of the present disclosure relates to an SFG (slanted fiber grating) that can easily realize a high-performance gain equalizer. The SFG includes an optical fiber comprised of silica-based glass and including a core, a first cladding containing a photosensitive material, and a second cladding. A specific section between two different points arranged along a fiber axis in the optical fiber is configured with a first region, a pair of second regions, and a third region. The first region includes a slanted Bragg grating provided in a region as the first cladding. The pair of second regions are arranged to sandwich the first region. The third region is disposed to sandwich both the first region and the pair of second regions. An MFD at a wavelength of 1.55 ?m in the third region is smaller than an MFD at a wavelength of 1.55 ?m in the first region.Type: GrantFiled: April 6, 2021Date of Patent: September 20, 2022Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Shigehiro Nagano, Manabu Shiozaki, Jun Kinugasa, Takemi Hasegawa
-
Publication number: 20210223468Abstract: One embodiment of the present disclosure relates to an SFG (slanted fiber grating) that can easily realize a high-performance gain equalizer. The SFG includes an optical fiber comprised of silica-based glass and including a core, a first cladding containing a photosensitive material, and a second cladding. A specific section between two different points arranged along a fiber axis in the optical fiber is configured with a first region, a pair of second regions, and a third region. The first region includes a slanted Bragg grating provided in a region as the first cladding. The pair of second regions are arranged to sandwich the first region. The third region is disposed to sandwich both the first region and the pair of second regions. An MFD at a wavelength of 1.55 ?m in the third region is smaller than an MFD at a wavelength of 1.55 ?m in the first region.Type: ApplicationFiled: April 6, 2021Publication date: July 22, 2021Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Shigehiro NAGANO, Manabu SHIOZAKI, Jun KINUGASA, Takemi HASEGAWA
-
Patent number: 10908353Abstract: An optical fiber is made of silica-based glass and includes a core, a first cladding that surrounds the core and that has a refractive index lower than a refractive index of the core; and a second cladding that surrounds the first cladding and that has a refractive index lower than the refractive index of the core and higher than the refractive index of the first cladding. At least a part of the first cladding contains a photosensitive material whose refractive index increases by irradiation with light having a specific wavelength. A difference ?n between a refractive index of a portion of the first cladding, the portion being nearest to the core, and the refractive index of the core is in a range of 0.25% to 0.30%. The radius ra of the core is larger than 4.3 ?m and smaller than or equal to 5.0 ?m.Type: GrantFiled: November 16, 2018Date of Patent: February 2, 2021Assignee: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Shigehiro Nagano, Manabu Shiozaki, Jun Kinugasa, Takemi Hasegawa
-
Publication number: 20190154912Abstract: An optical fiber is made of silica-based glass and includes a core, a first cladding that surrounds the core and that has a refractive index lower than a refractive index of the core; and a second cladding that surrounds the first cladding and that has a refractive index lower than the refractive index of the core and higher than the refractive index of the first cladding. At least a part of the first cladding contains a photosensitive material whose refractive index increases by irradiation with light having a specific wavelength. A difference ?n between a refractive index of a portion of the first cladding, the portion being nearest to the core, and the refractive index of the core is in a range of 0.25% to 0.30%. The radius ra of the core is larger than 4.3 ?m and smaller than or equal to 5.0 ?m.Type: ApplicationFiled: November 16, 2018Publication date: May 23, 2019Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Shigehiro NAGANO, Manabu SHIOZAKI, Jun KINUGASA, Takemi HASEGAWA
-
Patent number: 7773295Abstract: The present invention relates to an optical amplifier and the like having a flatter gain spectrum in the wavelength band of 1490 nm to 1520 nm than before. The optical amplifier according to the present invention comprises an Er-doped optical waveguide and a Tm-doped optical waveguide having gain spectra difference from each other in the wavelength band. The signal light entered through the input end is first amplified by the Er-doped optical waveguide, and thereafter is amplified by the Tm-doped optical waveguide. The gain deviation of the amplified signal light, which has been amplified in the Er- and Tm-doped optical waveguides and outputted through the output end, can be reduced over the wavelength band.Type: GrantFiled: March 23, 2009Date of Patent: August 10, 2010Assignee: Sumitomo Electric Industries, Ltd.Inventors: Motoki Kakui, Jun Kinugasa
-
Publication number: 20090185261Abstract: The present invention relates to an optical amplifier and the like having a flatter gain spectrum in the wavelength band of 1490 nm to 1520 nm than before. The optical amplifier according to the present invention comprises an Er-doped optical waveguide and a Tm-doped optical waveguide having gain spectra difference from each other in the wavelength band. The signal light entered through the input end is first amplified by the Er-doped optical waveguide, and thereafter is amplified by the Tm-doped optical waveguide. The gain deviation of the amplified signal light, which has been amplified in the Er- and Tm-doped optical waveguides and outputted through the output end, can be reduced over the wavelength band.Type: ApplicationFiled: March 23, 2009Publication date: July 23, 2009Applicant: SUMITOMO ELECTRIC INDUSTRIES, LTD.Inventors: Motoki KAKUI, Jun Kinugasa
-
Patent number: 7525725Abstract: The present invention relates to an optical amplifier and the like having a flatter gain spectrum in the wavelength band of 1490 nm to 1520 nm than before. The optical amplifier according to the present invention comprises an Er-doped optical waveguide and a Tm-doped optical waveguide having gain spectra difference from each other in the wavelength band. The signal light entered through the input end is first amplified by the Er-doped optical waveguide, and thereafter is amplified by the Tm-doped optical waveguide. The gain deviation of the amplified signal light, which has been amplified in the Er- and Tm-doped optical waveguides and outputted through the output end, can be reduced over the wavelength band.Type: GrantFiled: March 5, 2003Date of Patent: April 28, 2009Assignee: Sumitomo Electric Industries, Ltd.Inventors: Motoki Kakui, Jun Kinugasa
-
Publication number: 20030210844Abstract: The present invention relates to an optical amplifier and the like having a flatter gain spectrum in the wavelength band of 1490 nm to 1520 nm than before. The optical amplifier according to the present invention comprises an Er-doped optical waveguide and a Tm-doped optical waveguide having gain spectra difference from each other in the wavelength band. The signal light entered through the input end is first amplified by the Er-doped optical waveguide, and thereafter is amplified by the Tm-doped optical waveguide. The gain deviation of the amplified signal light, which has been amplified in the Er- and Tm-doped optical waveguides and outputted through the output end, can be reduced over the wavelength band.Type: ApplicationFiled: March 5, 2003Publication date: November 13, 2003Inventors: Motoki Kakui, Jun Kinugasa