Patents by Inventor Tomohiro Nakajima

Tomohiro Nakajima 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: 8081203
    Abstract: A light-amount detecting device includes: a light source which emits a light beam; a branching optical element which divides the light beam emitted from the light source into a first light beam traveling in a predetermined direction and a second light beam traveling in a direction different to the predetermined direction; a light-condensing element which condenses the second light beam; a light-receiving element having a light-receiving surface which receives the second light beam condensed by the light-condensing element; and a detector which detects a light-amount of the second light beam received by the light-receiving element, and at least one of a direction of reflected light of the second light beam reflected from the light-receiving surface of the light-receiving element and spread of the reflected light of the second light beam reflected from the light-receiving surface of the light-receiving element is adjusted to control a light-amount of the reflected light of the second light beam returning to the
    Type: Grant
    Filed: February 28, 2008
    Date of Patent: December 20, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Kensuke Masuda, Tomohiro Nakajima, Satoru Itoh, Daisuke Ichii, Masahiro Soeda, Yoshinori Hayashi
  • Publication number: 20110249984
    Abstract: An image forming apparatus including a plurality of image forming cartridges removably mounted to an apparatus body one above the other is disclosed. Structural members each partition off a space between nearby image forming cartridges mounted to the apparatus body. The apparatus is capable of obviating banding ascribable to the vibration of the cartridges.
    Type: Application
    Filed: June 23, 2011
    Publication date: October 13, 2011
    Inventors: Yasushi NAKAZATO, Kazuyuki Shimada, Tomohiro Nakajima
  • Patent number: 8023166
    Abstract: An optical scanning device includes, in an effective scanning area in the target surface, a mechanism that causes a scanning speed at each scanning position with respect to a scanning speed at an approximately center in the effective scanning area to be within a range under a predetermined condition.
    Type: Grant
    Filed: February 8, 2008
    Date of Patent: September 20, 2011
    Assignee: Ricoh Company, Limited
    Inventors: Tadashi Nakamura, Tomohiro Nakajima, Shigeaki Imai
  • Patent number: 7991321
    Abstract: An image forming apparatus including a plurality of image forming cartridges removably mounted to an apparatus body one above the other is disclosed. Structural members each partition off a space between nearby image forming cartridges mounted to the apparatus body. The apparatus is capable of obviating banding ascribable to the vibration of the cartridges.
    Type: Grant
    Filed: September 7, 2010
    Date of Patent: August 2, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasushi Nakazato, Kazuyuki Shimada, Tomohiro Nakajima
  • Patent number: 7956882
    Abstract: A multi-beam scanning device includes a light source part having a plurality of light emitting sources which light emitting sources are monolithically arranged in a surface perpendicular to an optical axis; a light deflection part configured to deflect a plurality of light beams from the light source part in a lump and scan an image carrier surface; and an image-formation optical system where lateral magnification is set so that beam spots of the plural light beams are arranged at a designated pitch in a sub-scanning direction on the image carrier surface.
    Type: Grant
    Filed: December 12, 2006
    Date of Patent: June 7, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • 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: 7924491
    Abstract: A disclosed optical scanning device includes: a light source unit having plural luminous sources; a light source driving unit modulating each luminous source in accordance with pixel information; an oscillating mirror supported on a twist beam as a rotation shaft, the oscillating mirror collectively deflecting light beams from the luminous sources and performing reciprocating scanning on a surface to be scanned; an imaging optical system imaging the light beams from the luminous sources on the surface to be scanned; an oscillating mirror driving unit setting a scanning frequency f in accordance with a resonance frequency of the oscillating mirror; and a pitch adjustment unit adjusting beam spot intervals p in a sub-scanning direction in accordance with the scanning frequency f of the oscillating mirror that has been set.
    Type: Grant
    Filed: July 1, 2010
    Date of Patent: April 12, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Patent number: 7916374
    Abstract: An optical scanning device is configured to identify a light-emitting unit at the start of writing on the basis of a sub-scanning resist displacement and selects a combination of four light-emitting units according to the light-emitting unit at the start of writing. The optical scanning device predicts the amount of deformation of pixel according to the combination and adjusts a light volume of light emission from a light-emitting unit to be corrected using the amount of deformation. Thereby, a pixel with an excellent shape quality can be constantly formed regardless of the combination of the light-emitting units and a pixel formed of multiple dots can be accurately and stably formed.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: March 29, 2011
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Publication number: 20110058230
    Abstract: An oscillating mirror module as a deflecting unit is disposed so that a movable mirror faces a plane where image carriers are arranged. A plurality of light source units are disposed within a plane parallel to the plane where the image carriers are arranged so that main light fluxes of light beams emitted from the light sources form predetermined angles with each other. The oscillating mirror module includes an incidence mirror that bends a plurality of light beams emitted from the light source units to direct the light beams to the movable mirror, and a separation mirror that separates the light beams scanned by the movable mirror into two opposite directions with respect to a cross-section including a surface normal of the movable mirror and perpendicular to the rotation axis of the movable mirror. A light collecting unit collects light beams so that output optical axes of the light beams corresponding to the light source units intersect on a surface of the movable mirror of the deflecting unit.
    Type: Application
    Filed: August 30, 2010
    Publication date: March 10, 2011
    Applicant: RICOH COMPANY, LTD.
    Inventors: Masahiro SOEDA, Tadashi Nakamura, Akira Kojima, Tomohiro Nakajima
  • Patent number: 7869110
    Abstract: An optical scan apparatus is configured to include a light source emitting a light beam; a vibration mirror deflecting the light beam emitted from the light source to scan a scan area; a drive unit driving the vibration mirror; and an optical imaging system focusing the light beam deflected by the vibration mirror on a predetermined focus position, and having optical power to correct a displacement of the focus position which occurs due to a deformation of the vibration mirror caused by its own vibration.
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: January 11, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadashi Nakamura, Tomohiro Nakajima
  • Publication number: 20100329733
    Abstract: An image forming apparatus including a plurality of image forming cartridges removably mounted to an apparatus body one above the other is disclosed. Structural members each partition off a space between nearby image forming cartridges mounted to the apparatus body. The apparatus is capable of obviating banding ascribable to the vibration of the cartridges.
    Type: Application
    Filed: September 7, 2010
    Publication date: December 30, 2010
    Inventors: Yasushi NAKAZATO, Kazuyuki Shimada, Tomohiro Nakajima
  • Publication number: 20100266313
    Abstract: A disclosed optical scanning device includes: a light source unit having plural luminous sources; a light source driving unit modulating each luminous source in accordance with pixel information; an oscillating mirror supported on a twist beam as a rotation shaft, the oscillating mirror collectively deflecting light beams from the luminous sources and performing reciprocating scanning on a surface to be scanned; an imaging optical system imaging the light beams from the luminous sources on the surface to be scanned; an oscillating mirror driving unit setting a scanning frequency f in accordance with a resonance frequency of the oscillating mirror; and a pitch adjustment unit adjusting beam spot intervals p in a sub-scanning direction in accordance with the scanning frequency f of the oscillating mirror that has been set.
    Type: Application
    Filed: July 1, 2010
    Publication date: October 21, 2010
    Inventor: Tomohiro Nakajima
  • Patent number: 7801462
    Abstract: An image forming apparatus including a plurality of image forming cartridges removably mounted to an apparatus body one above the other is disclosed. Structural members each partition off a space between nearby image forming cartridges mounted to the apparatus body. The apparatus is capable of obviating banding ascribable to the vibration of the cartridges.
    Type: Grant
    Filed: October 23, 2008
    Date of Patent: September 21, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasushi Nakazato, Kazuyuki Shimada, 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: 7773280
    Abstract: A disclosed optical scanning device includes: a light source unit having plural luminous sources; a light source driving unit modulating each luminous source in accordance with pixel information; an oscillating mirror supported on a twist beam as a rotation shaft, the oscillating mirror collectively deflecting light beams from the luminous sources and performing reciprocating scanning on a surface to be scanned; an imaging optical system imaging the light beams from the luminous sources on the surface to be scanned; an oscillating mirror driving unit setting a scanning frequency f in accordance with a resonance frequency of the oscillating mirror; and a pitch adjustment unit adjusting beam spot intervals p in a sub-scanning direction in accordance with the scanning frequency f of the oscillating mirror that has been set.
    Type: Grant
    Filed: March 2, 2007
    Date of Patent: August 10, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Publication number: 20100183337
    Abstract: A light source apparatus includes a circuit board on which a light source unit including a vertical-cavity surface-emitting light source and a package that houses the vertical-cavity surface-emitting light source is mounted, an optical element holder that holds a plurality of optical elements including at least a coupling lens, and an intermediate holder that is arranged between the circuit board and the optical element holder. The intermediate holder is joined to the circuit board to cover an area of the circuit board on which the light source unit is mounted to thereby make contact with the package such that the vertical-cavity surface-emitting light source is positioned and fixed and joined to the optical element holder to thereby position the optical elements to the vertical-cavity surface-emitting light source.
    Type: Application
    Filed: December 29, 2009
    Publication date: July 22, 2010
    Inventors: Nobuaki Kubo, Yasuhiro Naoe, Tomohiro Nakajima, Naoto Watanabe
  • Patent number: 7760227
    Abstract: A deflector includes a vibrating mirror supported by a torsion beam provided as a rotational axis and reciprocally scanning a beam from a light emitting source; and a rotational part configured to give a rotational torque to the vibrating mirror for making oscillation. The rotational part generates the rotational torque along one side separated from the rotational axis by length R in a direction perpendicular to the rotational axis. The vibration mirror has relationships of R<r,D>d,and D?d·(r/R)^2 where width in a direction perpendicular to the rotational axis of a mirror part that is a part of the vibrating mirror is 2r; width in a direction parallel with the rotational axis of the mirror part is d; and width of the separated one side causing generation of the rotational torque is D.
    Type: Grant
    Filed: June 19, 2007
    Date of Patent: July 20, 2010
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Patent number: 7729031
    Abstract: A line-imaging lens condenses a light beam from a light-source unit in one direction to form a line image. An optical deflecting unit deflects the light beam passing through the line-imaging lens. An imaging optical unit images the light beam deflected by the optical deflecting unit in a spot shape on a scanning surface to be scanned. An adjusting unit adjusts a position of irradiation of the light beam from the light-source unit on the optical deflecting unit.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: June 1, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Tadashi Nakamura, Yoshinori Hayashi, Naoki Miyatake, Tomohiro Nakajima
  • 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