Patents by Inventor Toshikazu Yamamoto
Toshikazu Yamamoto 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).
-
Patent number: 11175458Abstract: A multi-fiber connector fiber-optic measurement device identifies a polarity type and measures an optical power of a multi-fiber connector fiber-optic patch cord. The device includes: a beam splitter that splits light from the multi-fiber connector fiber-optic patch cord into a plurality of lights; a first optical sensor that receives one of the lights split by the beam splitter and outputs a first signal according to the received light; a second optical sensor that receives another of the lights split by the beam splitter and outputs a second signal according to the received light; and a signal processor that calculates the optical power based on the first signal and identifies the polarity type based on the second signal.Type: GrantFiled: May 28, 2020Date of Patent: November 16, 2021Assignees: YOKOGAWA ELECTRIC CORPORATION, Yokogawa Test & Measurement CorporationInventors: Katsushi Ota, Toshikazu Yamamoto
-
Patent number: 11108461Abstract: A method of testing a ribbon fiber cable is provided. The ribbon fiber cable includes optical fibers between a first end face and a second end face. End faces of the optical fibers are lined up in a single line in a line direction. The method includes: injecting light into each optical fiber at the second end face; measuring first power of the light exiting from each optical fiber at the first end face; disposing a member between the first end face and an optical sensor; injecting light into each optical fiber at the second end face; measuring second power of the light exiting from each optical fiber at the first end face; calculating a ratio of the second power to the first power; and testing an array of the optical fibers based on the ratio. Light transmittance of the member monotonically varies in the line direction.Type: GrantFiled: June 2, 2020Date of Patent: August 31, 2021Assignees: YOKOGAWA ELECTRIC CORPORATION, Yokogawa Test & Measurement CorporationInventors: Akira Tanigawa, Toshikazu Yamamoto
-
Publication number: 20210028858Abstract: A method of testing a ribbon fiber cable is provided. The ribbon fiber cable includes optical fibers between a first end face and a second end face. End faces of the optical fibers are lined up in a single line in a line direction. The method includes: injecting light into each optical fiber at the second end face; measuring first power of the light exiting from each optical fiber at the first end face; disposing a member between the first end face and an optical sensor; injecting light into each optical fiber at the second end face; measuring second power of the light exiting from each optical fiber at the first end face; calculating a ratio of the second power to the first power; and testing an array of the optical fibers based on the ratio. Light transmittance of the member monotonically varies in the line direction.Type: ApplicationFiled: June 2, 2020Publication date: January 28, 2021Applicants: YOKOGAWA ELECTRIC CORPORATION, Yokogawa Test & Measurement CorporationInventors: Akira Tanigawa, Toshikazu Yamamoto
-
Publication number: 20200379177Abstract: A multi-fiber connector fiber-optic measurement device identifies a polarity type and measures an optical power of a multi-fiber connector fiber-optic patch cord. The device includes: a beam splitter that splits light from the multi-fiber connector fiber-optic patch cord into a plurality of lights; a first optical sensor that receives one of the lights split by the beam splitter and outputs a first signal according to the received light; a second optical sensor that receives another of the lights split by the beam splitter and outputs a second signal according to the received light; and a signal processor that calculates the optical power based on the first signal and identifies the polarity type based on the second signal.Type: ApplicationFiled: May 28, 2020Publication date: December 3, 2020Applicants: YOKOGAWA ELECTRIC CORPORATION, Yokogawa Test & Measurement CorporationInventors: Katsushi Ota, Toshikazu Yamamoto
-
Publication number: 20180172512Abstract: An optical spectrum measurement device includes: a grating spectroscope that disperses an incident light, the grating spectroscope emitting the incident light from a slit; a plurality of photodiode sensors that has mutually different light receiving properties; a movable table on which the plurality of photodiode sensors is placed so as to align on a planar surface perpendicular to a traveling direction of an emitted light from the slit; and a driving mechanism that moves the movable table so as to have a state where the emitted light enters into any of the plurality of photodiode sensors.Type: ApplicationFiled: November 21, 2017Publication date: June 21, 2018Applicants: Yokogawa Electric Corporation, YOKOGAWA TEST & MEASUREMENT CORPORATIONInventors: Ryo TAMAKI, Manabu KOJIMA, Atsushi HORIGUCHI, Tsutomu KANEKO, Toshikazu YAMAMOTO, Tohru MORI
-
Patent number: 9146161Abstract: An optical wavelength meter includes: an interferometer; a reference optical source unit with a laser configured to oscillate in a multi-longitudinal mode; and a signal processor configured to calculate a wavelength of a input beam with reference to interference fringe information of reference beam and interference fringe information of the input beam obtained from the interferometer.Type: GrantFiled: November 1, 2013Date of Patent: September 29, 2015Assignees: YOKOGAWA ELECTRIC CORPORATION, YOKOGAWA METERS & INSTRUMENTS CORPORATIONInventors: Toshikazu Yamamoto, Manabu Kojima
-
Publication number: 20140125984Abstract: An optical wavelength meter includes: an interferometer; a reference optical source unit with a laser configured to oscillate in a multi-longitudinal mode; and a signal processor configured to calculate a wavelength of a input beam with reference to interference fringe information of reference beam and interference fringe information of the input beam obtained from the interferometer.Type: ApplicationFiled: November 1, 2013Publication date: May 8, 2014Applicants: Yokogawa Meters & Instruments Corporation, Yokogawa Electric CorporationInventors: Toshikazu YAMAMOTO, Manabu KOJIMA
-
Patent number: 8125638Abstract: An improvement is added to a spectroscope for performing wavelength dispersion of measured light with a wavelength dispersion element and receiving the light at a light reception element. The spectroscope has a first compound lens made up of a plurality of lenses for converting measured light into parallel light and emitting the parallel light to the wavelength dispersion element; a second compound lens made up of a plurality of lenses for gathering the measured light subjected to the wavelength dispersion in the wavelength dispersion element and causing the light reception element to receive the light; and a base for fixing the wavelength dispersion element, the first compound lens, and the second compound lens. The linear expansion coefficient of the compound focal length of the first compound lens, the linear expansion coefficient of the compound focal length of the second compound lens, and the linear expansion coefficient of a material forming the base are substantially equal.Type: GrantFiled: April 20, 2009Date of Patent: February 28, 2012Assignee: Yokogawa Electric CorporationInventors: Toshikazu Yamamoto, Tsutomu Kaneko, Manabu Kojima
-
Patent number: 7705984Abstract: A spectroscope includes a diffraction grating having a plurality of ruled parallel lines; and a plurality of spectroscopic paths, each of which has a collimator for collimating incident light, emits the collimated light to the diffraction grating, and emits return light, which returns from the diffraction grating, through a slit provided on the path. In the spectroscope, measured light is emitted through the plurality of spectroscopic paths so as to extract light which is included in the measured light and has a predetermined wavelength; and the collimators of the spectroscopic paths are arranged so that irradiation areas of light emitted from the collimators are offset from each other at least in a direction along the ruled parallel lines. The collimators of the spectroscopic paths may be arranged so that incident angles of light emitted from the collimators coincide with each other.Type: GrantFiled: January 15, 2009Date of Patent: April 27, 2010Assignee: Yokogawa Electric CorporationInventors: Manabu Kojima, Tsutomu Kaneko, Toshikazu Yamamoto
-
Patent number: 7649627Abstract: In a wavelength calibration method, an observed spectrum of a light that has a wavelength band is obtained, wherein the light has at least an attenuated wavelength component that corresponds to at least a predetermined absorption wavelength that is included in the wavelength band. A corrected spectrum is then obtained from the observed spectrum, wherein the corrected spectrum has reduced dependencies upon the full width at half maximum of an emission band of the light and upon an intensity ripple period of the light.Type: GrantFiled: February 8, 2007Date of Patent: January 19, 2010Assignee: Yokogawa Electric CorporationInventor: Toshikazu Yamamoto
-
Publication number: 20090262347Abstract: An improvement is added to a spectroscope for performing wavelength dispersion of measured light with a wavelength dispersion element and receiving the light at a light reception element. The spectroscope has a first compound lens made up of a plurality of lenses for converting measured light into parallel light and emitting the parallel light to the wavelength dispersion element; a second compound lens made up of a plurality of lenses for gathering the measured light subjected to the wavelength dispersion in the wavelength dispersion element and causing the light reception element to receive the light; and a base for fixing the wavelength dispersion element, the first compound lens, and the second compound lens. The linear expansion coefficient of the compound focal length of the first compound lens, the linear expansion coefficient of the compound focal length of the second compound lens, and the linear expansion coefficient of a material forming the base are substantially equal.Type: ApplicationFiled: April 20, 2009Publication date: October 22, 2009Applicant: YOKOGAWA ELECTRIC CORPORATIONInventors: Toshikazu YAMAMOTO, Tsutomu KANEKO, Manabu KOJIMA
-
Publication number: 20090190127Abstract: A spectroscope includes a diffraction grating having a plurality of ruled parallel lines; and a plurality of spectroscopic paths, each of which has a collimator for collimating incident light, emits the collimated light to the diffraction grating, and emits return light, which returns from the diffraction grating, through a slit provided on the path. In the spectroscope, measured light is emitted through the plurality of spectroscopic paths so as to extract light which is included in the measured light and has a predetermined wavelength; and the collimators of the spectroscopic paths are arranged so that irradiation areas of light emitted from the collimators are offset from each other at least in a direction along the ruled parallel lines. The collimators of the spectroscopic paths may be arranged so that incident angles of light emitted from the collimators coincide with each other.Type: ApplicationFiled: January 15, 2009Publication date: July 30, 2009Applicant: YOKOGAWA ELECTRIC CORPORATIONInventors: Manabu KOJIMA, Tsutomu Kaneko, Toshikazu Yamamoto
-
Publication number: 20070195318Abstract: In a wavelength calibration method, an observed spectrum of a light that has a wavelength band is obtained, wherein the light has at least an attenuated wavelength component that corresponds to at least a predetermined absorption wavelength that is included in the wavelength band. A corrected spectrum is then obtained from the observed spectrum, wherein the corrected spectrum has reduced dependencies upon the full width at half maximum of an emission band of the light and upon an intensity ripple period of the light.Type: ApplicationFiled: February 8, 2007Publication date: August 23, 2007Applicant: YOKOGAWA ELECTRIC CORPORATIONInventor: Toshikazu Yamamoto
-
Patent number: 7075644Abstract: A depolarizer includes a second birefringent plate having a thickness which continuously changes in a direction of an optical axis of the second birefringent plate; and a third birefringent plate having a thickness which continuously changes in a direction of 45 degree with respect to an optical axis of the third birefringent plate; wherein the second birefringent plate is stuck on the third birefringent plate so that a reduction direction of the thickness of the second birefringent plate and a reduction direction of the thickness of the third birefringent plate are opposite to each other.Type: GrantFiled: July 29, 2003Date of Patent: July 11, 2006Assignee: Yokogawa Electric CorporationInventors: Toshikazu Yamamoto, Tsutomu Kaneko, Toru Mori
-
Patent number: 6879396Abstract: A monochromator including: a concave mirror which converts incident light into parallel light and emits the parallel light, a plane diffraction grating for diffracting the parallel light emitted from the concave mirror, first reflection means which reflects first light diffracted by the plane diffraction grating and causes the diffracted light to enter the plane diffraction grating as second incident light, second reflection means which reflects second diffracted light and causes the reflected light to enter the plane diffraction grating as third incident light, and an exit slit disposed in the vicinity of a focal point such that third diffracted light is reflected by the first reflection means, to thereby enter the plane diffraction grating as fourth incident light and such that fourth diffracted light is converged at the focal point by the concave mirror, to thereby enable extraction of light having a specific wavelength.Type: GrantFiled: October 31, 2002Date of Patent: April 12, 2005Assignee: Ando Electric Co., Ltd.Inventors: Tsutomu Kaneko, Toshikazu Yamamoto, Tohru Mori
-
Patent number: 6744506Abstract: A depolarizing plate comprising a first rectangular wedge plate that has a first crystallographic optical axis in a diagonal direction of the rectangle and which has a thickness thereof in a vertical direction vary continuously in a direction 45 degrees from said first crystallographic optical axis and a second rectangular wedge plate that has a second crystallographic optical axis in a diagonal direction of the rectangle crossing said first crystallographic optical axis at right angles and which has a thickness thereof in a vertical direction vary continuously in a direction 45 degrees from said second crystallographic optical axis, the two wedge plates being joined in such a position that said first crystallographic optical axis crosses said second crystallographic optical axis at right angles, wherein the slope formed by the joint of said wedge plates is rotated about the optical axis of an incident ray of light.Type: GrantFiled: June 6, 2002Date of Patent: June 1, 2004Assignee: Ando Electric Co., Ltd.Inventors: Tsutomu Kaneko, Toshikazu Yamamoto
-
Publication number: 20040021942Abstract: A depolarizer includes a second birefringent plate having a thickness which continuously changes in a direction of an optical axis of the second birefringent plate; and a third birefringent plate having a thickness which continuously changes in a direction of 45 degree with respect to an optical axis of the third birefringent plate; wherein the second birefringent plate is stuck on the third birefringent plate so that a reduction direction of the thickness of the second birefringent plate and a reduction direction of the thickness of the third birefringent plate are opposite to each other.Type: ApplicationFiled: July 29, 2003Publication date: February 5, 2004Inventors: Toshikazu Yamamoto, Tsutomu Kaneko, Toru Mori
-
Patent number: 6654167Abstract: A polarization scrambler includes a Faraday element in which the thickness of a direction vertical to an optical axis changes continuously, and a magnetic field generator for generating a magnetic field in a direction of the optical axis with respect to the Faraday element.Type: GrantFiled: November 26, 2001Date of Patent: November 25, 2003Assignee: Ando Electric Co., Ltd.Inventor: Toshikazu Yamamoto
-
Publication number: 20030098975Abstract: An optical spectrum analyzer comprises a refractive grating which extracts a specific wavelength of light which is incident to be measured and outputs as a component light, an optical detector which measures optical intensity of the component light, a container in which the refractive grating and the optical detector are provided, a gas filling port and a gas exhaust port, for performing a replacement of air with a gas, which are provided in the container, are provided. By doing this, the optical spectrum analyzer which can measure level of the light to be measured having a specific wavelength accurately without causing the absorption of the specific wavelength by an OH group.Type: ApplicationFiled: November 22, 2002Publication date: May 29, 2003Applicant: Ando Electric Co., Ltd.Inventors: Tohru Mori, Tsutomu Kaneko, Toshikazu Yamamoto
-
Publication number: 20030081208Abstract: A monochromator including: a concave mirror which converts incident light into parallel light and emits the parallel light, a plane diffraction grating for diffracting the parallel light emitted from the concave mirror, first reflection means which reflects first light diffracted by the plane diffraction grating and causes the diffracted light to enter the plane diffraction grating as second incident light, second reflection means which reflects second diffracted light and causes the reflected light to enter the plane diffraction grating as third incident light, and an exit slit disposed in the vicinity of a focal point such that third diffracted light is reflected by the first reflection means, to thereby enter the plane diffraction grating as fourth incident light and such that fourth diffracted light is converged at the focal point by the concave mirror, to thereby enable extraction of light having a specific wavelength.Type: ApplicationFiled: October 31, 2002Publication date: May 1, 2003Applicant: Ando Electric Co., Ltd.Inventors: Tsutomu Kaneko, Toshikazu Yamamoto, Tohru Mori