Patents by Inventor Sunao Ichihara
Sunao Ichihara 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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Patent number: 10288701Abstract: Provided is an optically pumped atomic magnetometer that can separate and acquire magnetic information of spatially different places at the same time by one probe beam. The optically pumped atomic magnetometer includes a cell containing alkali metal atoms, a pump beam optical system introducing pump beams including circularly polarized light component to different locations of the cell, a probe beam optical system introducing a probe beam including linearly polarized light component to the cell, a detection unit detecting a signal reflecting a rotation angle of a plane of polarization of the probe beam after intersecting with the pump beams, and an information acquisition unit acquiring information related to a magnetic field intensity of each of the different locations from the detected signal. The pump beam optical system includes a modulation unit modulating the pump beams so that one of frequencies and phases of the pump beams is different.Type: GrantFiled: August 10, 2015Date of Patent: May 14, 2019Assignee: CANON KABUSHIKI KAISHAInventors: Tetsuo Kobayashi, Yosuke Ito, Sunao Ichihara, Natsuhiko Mizutani
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Patent number: 9964609Abstract: There is provided an optically pumped magnetometer, in which a pump light having a first wavelength to spin-polarize a first alkali-metal atom group is made to enter a cell containing the first alkali-metal atom group and a second alkali-metal atom group interacting via spin exchange with the first alkali-metal atom group, a probe light having a second wavelength different from the first wavelength to measure spin polarization of the second alkali-metal atom group is made to enter the cell to form the same optical axis as the pump light, a wavelength discrimination unit is provided to discriminate between the pump light and the probe light that passed through the cell depending on a different in wavelength, and the rotation angle of a polarization plane of the probe light that passed through the cell is measured so that the degree of flexibility of the device layout can be increased.Type: GrantFiled: April 10, 2013Date of Patent: May 8, 2018Assignee: CANON KABUSHIKI KAISHAInventors: Sunao Ichihara, Natsuhiko Mizutani, Tetsuo Kobayashi, Shuji Taue
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Publication number: 20170023653Abstract: An optically pumped magnetometer and a magnetic sensing method are provided. The optically pumped magnetometer is an atomic magnetic sensor that measures a magnetic field at multiple locations in a single cell and that can separate and simultaneously measure magnetic information of spatially different places in a configuration in which a plurality of probe lights or pump lights are radiated. An optically pumped magnetometer and a magnetic sensing method are provided which, by radiating a relaxing light between a plurality of measurement regions constituted by a pump light and a probe light, prevent mixing of spin polarization and separate spatially different magnetic signals with high accuracy.Type: ApplicationFiled: July 6, 2016Publication date: January 26, 2017Inventors: Tetsuo Kobayashi, Yosuke Ito, Sunao Ichihara, Natsuhiko Mizutani
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Publication number: 20170023654Abstract: Provided are an optically pumped magnetometer, comprising: at least one cell containing alkali metal atoms; a pump light optical system configured to cause pump light to enter the cell; a probe light optical system configured to cause probe light to enter the at least one cell so as to intersect with the pump light in the at least one cell; a relaxing light optical system configured to cause a plurality of relaxing lights to enter different positions in an intersection region between the pump light and the probe light; a unit configured to detect the probe light having intersected with the pump light and the plurality of relaxing lights, to thereby output a detection signal; and a unit configured to acquire information on a magnetic field intensity of each of the different positions from the detection signal.Type: ApplicationFiled: July 6, 2016Publication date: January 26, 2017Inventors: Tetsuo Kobayashi, Yosuke Ito, Sunao Ichihara, Natsuhiko Mizutani
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Publication number: 20160061913Abstract: Provided is an optically pumped atomic magnetometer that can separate and acquire magnetic information of spatially different places at the same time by one probe beam. The optically pumped atomic magnetometer includes a cell containing alkali metal atoms, a pump beam optical system introducing pump beams including circularly polarized light component to different locations of the cell, a probe beam optical system introducing a probe beam including linearly polarized light component to the cell, a detection unit detecting a signal reflecting a rotation angle of a plane of polarization of the probe beam after intersecting with the pump beams, and an information acquisition unit acquiring information related to a magnetic field intensity of each of the different locations from the detected signal. The pump beam optical system includes a modulation unit modulating the pump beams so that one of frequencies and phases of the pump beams is different.Type: ApplicationFiled: August 10, 2015Publication date: March 3, 2016Inventors: Tetsuo Kobayashi, Yosuke Ito, Sunao Ichihara, Natsuhiko Mizutani
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Publication number: 20150054504Abstract: An optically pumped magnetometer includes: a modulation unit which allows rectangular wave modulation to an angle of a polarization plane of probe light; a detector for detecting a change of the angle of the polarization plane of the probe light transmitted through a cell; and a differential circuit for obtaining a difference in light intensity between components separated by a polarization splitter. Thus, both a reduction of a light intensity noise of the probe light and a separation and reduction of a noise defined by an inverse of a frequency in a low frequency area can be achieved.Type: ApplicationFiled: March 26, 2013Publication date: February 26, 2015Applicant: Canon Kabushiki KaishaInventors: Sunao Ichihara, Tetsuo Kobayashi, Kiyoshi Ishikawa
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Publication number: 20150022200Abstract: An optically pumped magnetometer having a single optical axis using atomic electron spin or nuclear spin includes a detection unit configured to detect an angle of a polarization plane of probe light having components of linear polarization and a modulation unit configured to apply a modulation to the angle of the polarization plane of the probe light having the components of linear polarization. The modulation unit is configured to control an offset in applying the modulation to the angle of the polarization plane of the probe light having the components of linear polarization according to the angle of the polarization plane of the probe light detected by the detection unit.Type: ApplicationFiled: July 15, 2014Publication date: January 22, 2015Inventors: Sunao Ichihara, Tetsuo Kobayashi
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Publication number: 20130278253Abstract: There is provided an optically pumped magnetometer, in which a pump light having a first wavelength to spin-polarize a first alkali-metal atom group is made to enter a cell containing the first alkali-metal atom group and a second alkali-metal atom group interacting via spin exchange with the first alkali-metal atom group, a probe light having a second wavelength different from the first wavelength to measure spin polarization of the second alkali-metal atom group is made to enter the cell to form the same optical axis as the pump light, a wavelength discrimination unit is provided to discriminate between the pump light and the probe light that passed through the cell depending on a different in wavelength, and the rotation angle of a polarization plane of the probe light that passed through the cell is measured so that the degree of flexibility of the device layout can be increased.Type: ApplicationFiled: April 10, 2013Publication date: October 24, 2013Applicant: CANON KABUSHIKI KAISHAInventors: Sunao Ichihara, Natsuhiko Mizutani, Tetuo Kobayashi, Syuji Taue
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Patent number: 8405389Abstract: An atomic magnetometer includes a light source for a probe beam and a medium in which the probe beam is to be propagated. The medium is a substance which changes a polarization rotation angle of the probe beam depending on a magnetic field intensity at a first measurement position and a magnetic field intensity at a second measurement position different from the first measurement position. The atomic magnetometer directly measures a difference between the magnetic field intensity at the first measurement position and the magnetic field intensity at the second measurement position as a difference in polarization rotation angle, along a propagation path of the probe beam.Type: GrantFiled: December 26, 2008Date of Patent: March 26, 2013Assignee: Canon Kabushiki KaishaInventors: Hideyuki Sugioka, Sunao Ichihara
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Patent number: 8054074Abstract: An atomic magnetometer includes a cell containing an atomic group, a pump light source, a probe light source, a mirror, and a detector. The cell is disposed between the pump light source and the mirror and between the probe light source and the detector. A pump beam emitted from the pump light source is circularly polarized light. The pump beam passes through the cell and is reflected by the mirror and then passes through the cell again. The probe beam emitted from the probe light source is linearly polarized light. An optical path of the probe beam is parallel to the plane of incidence of the pump beam and is also parallel to the surface of the mirror. The optical path of the probe beam crosses the optical path of the pump beam in the cell. The probe beam which has passed through the cell enters the detector.Type: GrantFiled: March 24, 2009Date of Patent: November 8, 2011Assignee: Canon Kabushiki KaishaInventors: Sunao Ichihara, Natsuhiko Mizutani, Hideyuki Sugioka, Tetsuo Kobayashi, Kiyoshi Ishikawa, Shuji Taue
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Publication number: 20110193555Abstract: An atomic magnetometer includes a light source for a probe beam and a medium in which the probe beam is to be propagated. The medium is a substance which changes a polarization rotation angle of the probe beam depending on a magnetic field intensity at a first measurement position and a magnetic field intensity at a second measurement position different from the first measurement position. The atomic magnetometer directly measures a difference between the magnetic field intensity at the first measurement position and the magnetic field intensity at the second measurement position as a difference in polarization rotation angle, along a propagation path of the probe beam.Type: ApplicationFiled: December 26, 2008Publication date: August 11, 2011Applicant: CANON KABUSHIKI KAISHAInventors: Hideyuki Sugioka, Sunao Ichihara
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Publication number: 20090243610Abstract: An atomic magnetometer includes a cell containing an atomic group, a pump light source, a probe light source, a mirror, and a detector. The cell is disposed between the pump light source and the mirror and between the probe light source and the detector. A pump beam emitted from the pump light source is circularly polarized light. The pump beam passes through the cell and is reflected by the mirror and then passes through the cell again. The probe beam emitted from the probe light source is linearly polarized light. An optical path of the probe beam is parallel to a plane of incidence of the pump beam and is also parallel to a surface of the mirror. The optical path of the probe beam crosses an optical path of the pump beam in the cell. The probe beam which has passed through the cell enters the detector.Type: ApplicationFiled: March 24, 2009Publication date: October 1, 2009Applicant: CANON KABUSHIKI KAISHAInventors: Sunao Ichihara, Natsuhiko Mizutani, Hideyuki Sugioka, Tetsuo Kobayashi, Kiyoshi Ishikawa, Shuji Taue
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Patent number: 5489180Abstract: A vibration damping construction, which is useful when it is applied to a vibration isolation washer or a pressed construction such as an oil pan, a ventilation buffle plate, etc. for an automobile, is disclosed, which is so constructed that raw materials, in each of which a rubber visco-elastic layer or such layers is or are disposed on one or two surfaces of a metal plate, are laminated on each other, so that rubber visco-elastic layers are opposite to each other, and adhered to each other to form a laminated body; rectangular pawls are formed on the raw material at the uppermost layer and the laminated body; rectangular cut-off windows, with which the cut and raised pawls can be engaged, are formed in the raw material at the lowermost layer; and these are laminated on each other and bound in one body by spot connection by means of the pawls.Type: GrantFiled: March 31, 1994Date of Patent: February 6, 1996Assignees: Toyota Jidosha Kabushiki Kaisha, Nichias CorporationInventors: Sunao Ichihara, Kunihiko Yano, Takahiro Niwa, Shyuichi Ishiwa, Katsunori Ueda