Patents by Inventor Taku Amada

Taku Amada 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: 9228825
    Abstract: An objective is to achieve a positional change measurement device which measures positional change of a dynamic measured surface by using speckle patterns while easily reducing influence of fluctuations in a measurement environment temperature. Provided is a positional change measurement device including: a light source; an illuminating optical system configured to guide light from the light source to a measured surface; an imaging optical system; an image pickup device configured to acquire a speckle pattern by receiving reflection light from the measured surface via the imaging optical system; and detected-length compensation means for compensating for fluctuations in a detected length caused by temperature fluctuations. Positional change of the measured surface is measured based on a result of cross-correlation computation performed on multiple speckle patterns acquired at predetermined time intervals.
    Type: Grant
    Filed: March 13, 2014
    Date of Patent: January 5, 2016
    Assignee: RICOH COMPANY, LTD.
    Inventors: Atsushi Takaura, Koji Masuda, Yasuhiro Nihei, Takeshi Ueda, Koichi Kudo, Taku Amada, Kenichi Shimizu, Asato Tamura
  • Patent number: 8928716
    Abstract: An optical scanning device includes: a light source device that emits five light beams corresponding to four basic colors and a single specific color; and five scanning optical systems corresponding the five light beams. One light beam in a first waveband among the light beams corresponding to the four basic colors enters one scanning optical system of the five scanning optical systems. The one scanning optical system includes a dichroic mirror that transmits a light beam in a second waveband different from the first waveband. An angle ?b formed between a normal to the incidence plane of the dichroic mirror and orthogonal projection to an assumed plane orthogonal to the main scanning corresponding direction of the incident path of the light beam to the incidence plane of the dichroic mirror is set at an angle of 0° or more and an angle of 45° or less.
    Type: Grant
    Filed: February 4, 2013
    Date of Patent: January 6, 2015
    Assignee: Ricoh Company, Limited
    Inventors: Tadashi Nakamura, Toshiaki Tokita, Yukio Itami, Taku Amada, Shingo Tachikawa
  • Patent number: 8908001
    Abstract: An optical scanning device includes a plurality of stations, each of which includes an light source, a deflector (polygon scan), a scanning optical element, and a housing. The light source emits a light beam to a plurality of surfaces to be scanned. The deflector deflects light beams emitted from the light source. The scanning optical element scans the surfaces to be scanned with light spots of the optical beams deflected by the deflector. The housing houses therein the light source, the deflector, and the scanning optical element. The scanning optical element is secured to the housing so that directions of scanning-line curves caused by temperature change match between the surfaces to be scanned.
    Type: Grant
    Filed: August 31, 2007
    Date of Patent: December 9, 2014
    Assignee: Ricoh Company, Limited
    Inventor: Taku Amada
  • Publication number: 20140268180
    Abstract: An objective is to achieve a positional change measurement device which measures positional change of a dynamic measured surface by using speckle patterns while easily reducing influence of fluctuations in a measurement environment temperature. Provided is a positional change measurement device including: a light source; an illuminating optical system configured to guide light from the light source to a measured surface; an imaging optical system; an image pickup device configured to acquire a speckle pattern by receiving reflection light from the measured surface via the imaging optical system; and detected-length compensation means for compensating for fluctuations in a detected length caused by temperature fluctuations. Positional change of the measured surface is measured based on a result of cross-correlation computation performed on multiple speckle patterns acquired at predetermined time intervals.
    Type: Application
    Filed: March 13, 2014
    Publication date: September 18, 2014
    Inventors: Atsushi TAKAURA, Koji MASUDA, Yasuhiro NIHEI, Takeshi UEDA, Koichi KUDO, Taku AMADA, Kenichi SHIMIZU, Asato TAMURA
  • Patent number: 8593497
    Abstract: An optical scanning device that optically scans a surface to be scanned in a main-scanning direction includes a light source; an optical deflector that has a reflective surface rotating on an axis of rotation of the reflective surface and deflects a light beam emitted from the light source; a scanning optical system that guides the light beam deflected by the optical deflector to the surface to be scanned; and a flow guide member that is provided near the optical deflector and turns back a flow of air generated by rotation of the reflective surface toward the reflective surface.
    Type: Grant
    Filed: August 8, 2011
    Date of Patent: November 26, 2013
    Assignee: Ricoh Company, Limited
    Inventors: Taku Amada, Tomohiro Nakajima
  • Publication number: 20130201536
    Abstract: An optical scanning device includes: a light source device that emits five light beams corresponding to four basic colors and a single specific color; and five scanning optical systems corresponding the five light beams. One light beam in a first waveband among the light beams corresponding to the four basic colors enters one scanning optical system of the five scanning optical systems. The one scanning optical system includes a dichroic mirror that transmits a light beam in a second waveband different from the first waveband. An angle ?b formed between a normal to the incidence plane of the dichroic mirror and orthogonal projection to an assumed plane orthogonal to the main scanning corresponding direction of the incident path of the light beam to the incidence plane of the dichroic mirror is set at an angle of 0° or more and an angle of 45° or less.
    Type: Application
    Filed: February 4, 2013
    Publication date: August 8, 2013
    Inventors: Tadashi NAKAMURA, Toshiaki Tokita, Yukio Itami, Taku Amada, Shingo Tachikawa
  • Patent number: 8270053
    Abstract: A holding mechanism for a long length optical element, which extends in a main scanning direction that is a movement direction of a deflected luminous flux by an optical deflector, and leads the deflected luminous flux to a scanned surface, includes; a holding member which is placed in a sub-scanning direction orthogonal to the main scanning direction and holds the long length optical element in at least two places. The holding member has, an adjusting section which deflects the long length optical element in the sub-scanning direction and controls a tilt of the long length optical element in a sub-scanning cross-section and/or occurrences of a tilt distribution in a longitudinal direction in the sub-scanning cross-section.
    Type: Grant
    Filed: August 21, 2008
    Date of Patent: September 18, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Hiromichi Atsuumi
  • Patent number: 8228583
    Abstract: An optical scanning device includes: a light source unit that includes a light emitting unit composed of a laser light source emitting linearly polarized light inside a package member; a deflector that deflects a light beam emitted from the light emitting unit; a pre-deflector optical system arranged on an optical path between the light emitting unit and the deflector; and a scanning optical system that scans a target surface to be scanned with the light beam deflected by the deflector. The pre-deflector optical system includes at least two parallel plate optical elements each composed of a transparent medium having an incident surface and an exit surface parallel to each other. The parallel plate optical elements are arranged to be tilted in inclination that is opposite to each other in a plane of polarization of the linearly polarized light.
    Type: Grant
    Filed: May 27, 2011
    Date of Patent: July 24, 2012
    Assignee: Ricoh Company, Limited
    Inventors: Taku Amada, Hibiki Tatsuno
  • Patent number: 8217978
    Abstract: An optical scanning apparatus, an image formation apparatus, and a phase modulation method are disclosed. The optical scanning apparatus includes a liquid crystal device for deflecting an optical beam irradiated by a semiconductor laser. The driving voltages for the liquid crystal device are controlled based on, e.g., the temperature of the liquid crystal device so that degradation of the diameter of a spot of the optical beam due to wavefront aberration is prevented.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: July 10, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Tomohiro Nakajima, Akihisa Itabashi, Seizo Suzuki
  • Patent number: 8174747
    Abstract: An optical scanning apparatus for scanning a surface to be scanned includes: a light source that emits laser beam; a deflector that deflects the laser beam emitted from the light source; a plurality of optical scanning elements that introduce the deflected laser beam to the surface to be scanned; a housing that holds therein at least one of the light source, the deflector, and the scanning optical elements; a light receiving element that receives the deflected laser beam; a mirror that introduces the deflected laser beam to the light receiving element; and a holder that is provided on the housing and that holds the light receiving element and the mirror integrally.
    Type: Grant
    Filed: June 24, 2009
    Date of Patent: May 8, 2012
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Atsuhiko Ogawa
  • Publication number: 20120044316
    Abstract: An optical scanning device that optically scans a surface to be scanned in a main-scanning direction includes a light source; an optical deflector that has a reflective surface rotating on an axis of rotation of the reflective surface and deflects a light beam emitted from the light source; a scanning optical system that guides the light beam deflected by the optical deflector to the surface to be scanned; and a flow guide member that is provided near the optical deflector and turns back a flow of air generated by rotation of the reflective surface toward the reflective surface.
    Type: Application
    Filed: August 8, 2011
    Publication date: February 23, 2012
    Inventors: Taku AMADA, Tomohiro Nakajima
  • Publication number: 20110310450
    Abstract: An optical scanning device includes: a light source unit that includes a light emitting unit composed of a laser light source emitting linearly polarized light inside a package member; a deflector that deflects a light beam emitted from the light emitting unit; a pre-deflector optical system arranged on an optical path between the light emitting unit and the deflector; and a scanning optical system that scans a target surface to be scanned with the light beam deflected by the deflector. The pre-deflector optical system includes at least two parallel plate optical elements each composed of a transparent medium having an incident surface and an exit surface parallel to each other. The parallel plate optical elements are arranged to be tilted in inclination that is opposite to each other in a plane of polarization of the linearly polarized light.
    Type: Application
    Filed: May 27, 2011
    Publication date: December 22, 2011
    Inventors: Taku AMADA, Hibiki Tatsuno
  • Patent number: 8031362
    Abstract: A disclosed optical scanning device scans an object scanning surface with a light beam projected from a light source and traveling through an optical system. The optical scanning device includes a liquid crystal element configured to modulate a phase. The liquid crystal element is driven by electric signals and provided on a light path between the light source and the object scanning surface. The liquid crystal element generates different power components in a main scanning direction and a sub scanning direction under temperature variations.
    Type: Grant
    Filed: October 5, 2006
    Date of Patent: October 4, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Taku Amada
  • Patent number: 7936492
    Abstract: An optical splitting member splits a light beam emitted by a light source into first light beam and second light beam. A coupling member couples the first light beam. An optical system converges the second light beam on a light receiving unit. A holding member holds the light source, the optical splitting member, the coupling member, and the optical system. A supporting member supports the holding member so that the holding member is rotatable about an optical axis of the light beam.
    Type: Grant
    Filed: March 19, 2008
    Date of Patent: May 3, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Tomohiro Nakajima
  • Patent number: 7800641
    Abstract: A light source unit is provided, which includes a light source with a plurality of light emission portions two-dimensionally arranged; a substrate on which the light source is mounted; a first support portion supporting the substrate; a bias member biasing the substrate towards the first support portion; a coupling element coupling a light beam emitted from the light source; a second support portion supporting the coupling element; a holding member holding a position of the substrate relative to the first support portion, a fitting portion provided in each of the first and second support portions to rotatably fit the first and second support portions into each other around an optical axis of the light source; and a fastening member integrally fastening the first and second support portions.
    Type: Grant
    Filed: August 19, 2008
    Date of Patent: September 21, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Nobuaki Kubo, Tomohiro Nakajima, Taku Amada, Yoshinori Hayashi
  • Patent number: 7777774
    Abstract: An optical scanning characteristic control method is applied to an optical scanning system in which a beam is deflected, and the deflected beam is converged and directed toward a scanning surface, so that optical scanning of the scanning surface is performed by an optical spot formed thereon by the deflected beam. The method comprising the steps of a) disposing a beam deflection control device on the light path of the beam before it is incident on the scanning surface; and b) controlling a beam deflection amount of the beam deflecting device provide to an incident beam so as to control a scanning characteristic of the optical scanning.
    Type: Grant
    Filed: May 23, 2006
    Date of Patent: August 17, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuo Suzuki, Naoki Miyatake, Taku Amada, Seizo Suzuki, Kazuyuki Shimada, Satoru Itoh
  • Patent number: 7719737
    Abstract: An optical scanning device includes a laser-beam-phase-modulatable liquid crystal device. The liquid crystal device has stripe-like electrode patterns arranged in one direction, with a provision of a part for changing an effective value of a driving voltage separately for each of stripe-like electrode patterns.
    Type: Grant
    Filed: January 4, 2008
    Date of Patent: May 18, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Seizo Suzuki, Akihisa Itabashi, Hiroyuki Suhara, Mitsuo Suzuki
  • Patent number: 7710445
    Abstract: A light source unit is provided which includes a light source with a plurality of light emission portions two-dimensionally arranged; a substrate on which the light source is mounted; a first support portion supporting the substrate; a bias member biasing the substrate towards the first support portion; a coupling element coupling a light beam emitted from the light source; a second support portion supporting the coupling element; and a holding member holding a position of the substrate relative to the first support portion.
    Type: Grant
    Filed: August 26, 2008
    Date of Patent: May 4, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Tomohiro Nakajima, Yoshinori Hayashi, Nobuaki Kubo
  • Patent number: 7706040
    Abstract: An optical scanning apparatus scans a surface to be scanned in a main scanning direction by simultaneously using a plurality of optical spots formed of a plurality of optical beams emitted from an illuminant, comprising: a light path deflecting part deflecting a light path of at least one of the optical beams, wherein the light path deflecting part is provided in light paths of the optical beams wherein the light path deflecting part may use a liquid crystal deflecting element formed of a liquid crystal element being controllable by an electronic signal to deflect the light path of the one of the optical beams.
    Type: Grant
    Filed: January 9, 2008
    Date of Patent: April 27, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Taku Amada, Seizo Suzuki, Satoru Itoh, Tomohiro Nakajima
  • Patent number: RE42865
    Abstract: An optical scanning characteristic control method is applied to an optical scanning system in which a beam is deflected, and the deflected beam is converged and directed toward a scanning surface, so that optical scanning of the scanning surface is performed by an optical spot formed thereon by the deflected beam. The method comprising the steps of a) disposing a beam deflection control device on the light path of the beam before it is incident on the scanning surface; and b) controlling a beam deflection amount of the beam deflecting device provide to an incident beam so as to control a scanning characteristic of the optical scanning.
    Type: Grant
    Filed: May 25, 2007
    Date of Patent: October 25, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsuo Suzuki, Naoki Miyatake, Taku Amada, Seizo Suzuki, Kazuyuki Shimada, Satoru Itoh