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).

  • LIGHT DEFLECTOR, OPTICAL SCANNER, AND IMAGE FORMING APPARATUS
    Publication number: 20070146856
    Abstract: A light deflector is disclosed that includes a movable mirror serving as a deflector supported by a rotary shaft and configured to deflect a light beam emitted from a light source and scan an area to be scanned; a rotation part configured to cause the movable mirror to vibrate in a reciprocating manner by periodically applying a rotational torque to the movable mirror; a driving circuit configured to control the rotation part; a circuit board having the driving circuit provided thereon, the circuit board being configured to support the movable mirror as a unit; a contact plane contacting the circuit board in a plane perpendicular to the rotary shaft of the movable mirror; and a positioning part configured to determine the position of the rotary shaft in the contact plane.
    Type: Application
    Filed: November 20, 2006
    Publication date: June 28, 2007
    Inventor: Tomohiro NAKAJIMA
  • Vibration mirror, optical scanning device, and image forming using the same, method for making the same, and method for scanning image
    Patent number: 7221493
    Abstract: A vibration mirror is reciprocatively vibrated by an electrostatic force to reflect an incident light beam.
    Type: Grant
    Filed: September 30, 2004
    Date of Patent: May 22, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Mitsumi Fujii, Yukito Satoh, Tomohiro Nakajima
  • Optical scanner and image forming apparatus
    Publication number: 20070058255
    Abstract: An optical scanner includes a light source; a deflecting unit that deflects and scans a light beam emitted from the light source; a scanning optical system that focuses the light beam deflected and scanned onto different surfaces to be scanned; and a light quantity correcting unit that corrects a light quantity of the light beam. The light quantity correcting unit changes light quantity correction data used for correcting the light quantity of the light beam for each of the surfaces. The light quantity correction data is dependent on positions in a main scanning direction.
    Type: Application
    Filed: August 24, 2006
    Publication date: March 15, 2007
    Inventors: Shigeaki Imai, Tomohiro Nakajima, Yoshinori Hayashi
  • Multi-beam luminous source apparatus, an optical scanning apparatus, and an image formation apparatus
    Publication number: 20070058232
    Abstract: A multi-beam luminous source apparatus, an optical scanning apparatus, and an image formation apparatus are disclosed. The multi-beam luminous source includes a first member for supporting a coupling lens and a second member for supporting a control substrate that supports a Vertical Cavity Surface Emitting Laser (VCSEL). The first member and the second member are joined with a screw at a reference plane that perpendicularly intersects an optical axis of the coupling lens. The second member includes a base member A for supporting the control substrate and a base member B that includes a branch mirror, a convergent lens, and an optical detection sensor.
    Type: Application
    Filed: September 14, 2006
    Publication date: March 15, 2007
    Inventor: Tomohiro Nakajima
  • Optical scanning apparatus and image forming apparatus
    Publication number: 20070035796
    Abstract: A disclosed optical scanning apparatus for scanning a scanning surface using a light beam, the optical scanning apparatus comprises: a light source having a plurality of luminous sources; a deflection unit collectively deflecting a plurality of light beams emitted from the plural luminous sources; a light guiding unit guiding at least a portion of each of the plural light beams to a predetermined direction without using the deflection unit; and a photo-detection system receiving the plural guided light beams and the plural deflected light beams and outputting a signal based on the received light beams.
    Type: Application
    Filed: August 2, 2006
    Publication date: February 15, 2007
    Inventor: Tomohiro Nakajima
  • Image forming apparatus
    Publication number: 20070036583
    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: October 17, 2006
    Publication date: February 15, 2007
    Inventors: Yasushi Nakazato, Kazuyuki Shimada, Tomohiro Nakajima
  • Optical scanner and image forming device
    Patent number: 7170660
    Abstract: An image forming device comprises a plurality of unit modules arranged in a main scanning direction, each unit module having a light source that modulates according to image data and a deflection unit which deflects the light emitted from the light source to scan a surface to be scanned. Areas scanned with each unit module are joined together to record the image. The image data includes fixed pixel areas in number equal to the number of the unit modules and which have one scanning line in common with the adjacent fixed pixel area, and variable pixel areas that link up the fixed pixel areas. The image data is constructed by adding pixels of each unit module to the variable pixel areas at a record start side or a record stop side of the fixed pixel areas, and the variable pixel areas are commonly shared between two neighboring unit modules.
    Type: Grant
    Filed: April 23, 2002
    Date of Patent: January 30, 2007
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Image forming apparatus including image transfer belt conveying a recording medium upward
    Patent number: 7139509
    Abstract: An image forming apparatus includes a plurality of cartridges disposed at intervals along an image transfer belt. A plurality of image writing devices is configured to write images. A partition member separates the plurality of cartridges from the plurality of image writing devices. The partition member defines slits configured to permit optical beams from the plurality of image writing devices to pass therethrough. The image transfer belt conveys the recording medium upward.
    Type: Grant
    Filed: June 17, 2005
    Date of Patent: November 21, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasushi Nakazato, Kazuyuki Shimada, Tomohiro Nakajima
  • Optical scanning device and image forming apparatus
    Publication number: 20060245009
    Abstract: A vibration mirror used in an optical scanning device has two reflection surfaces on opposite sides. A pair of light beams corresponding to a pair of different colors are irradiated on one reflection surface and another pair of light beams corresponding to another pair of different colors are irradiated on other reflection surface. If there are fluctuations in dimensions or a change in temperature, because the vibration mirror is one, all the colors are subjected to the same influences.
    Type: Application
    Filed: April 5, 2006
    Publication date: November 2, 2006
    Inventors: Hiroshi Akiyama, Yoshinori Hayashi, Tomohiro Nakajima
  • Optical scanner and image forming apparatus
    Publication number: 20060232660
    Abstract: An optical scanner is capable of effectively correcting a difference with respect to the sub-scanning direction between the positions of optical spots for scanning photoconductor drums of a tandem type color image forming apparatus. The optical scanner includes an optical axis adjusting part. The optical axis adjusting part uses a deflecting mirror or a wedge-shaped prism to deflect the optical axis of an optical beam with respect to the sub-scanning direction. As a result, it is possible to accurately correct a resist difference among individual image forming stations and form a high-quality color image without any color displacement.
    Type: Application
    Filed: June 13, 2006
    Publication date: October 19, 2006
    Inventors: Tomohiro Nakajima, Akira Kojima, Ikuko Yamashiro, Seizo Suzuki, Taku Amada, Yoshinori Hayashi, Kazuyuki Shimada
  • Optical scanning apparatus and image forming apparatus
    Publication number: 20060232844
    Abstract: An optical scanning apparatus includes a housing that positions and holds a plurality of light sources emitting light beams, a deflection mirror that deflects the light beams to perform main scanning, and at least one of optical image forming elements closest to the deflection mirror to form images on respective image carriers. A plurality of reflectors guide the light beams exiting the housing to the respective image carriers. A pair of support members face each other to support the housing in a main scanning direction. A support mechanism supports the reflectors by bridging the reflectors between the support members and also couples the support members to each other. Relative positions of the reflectors are arranged in a cross-sectional plane perpendicular to a main scanning direction between the support members.
    Type: Application
    Filed: February 17, 2006
    Publication date: October 19, 2006
    Inventor: Tomohiro Nakajima
  • Image forming device and image forming method
    Publication number: 20060158711
    Abstract: An image forming device is disclosed that is able to correct an image distortion even when the installation environment changes or unexpected shocks occur and even when an optical scanning device is exchanged. The image forming device comprises a light source, an optical scanning unit, a development unit, a transfer unit, a test image output unit to output a test image able to determine unevenness of intervals of positions of beam spots formed on an image supporting member, a beam spot position correction unit to correct the unevenness of the beam spot position intervals, and a correction data input unit to select correction data of the unevenness of the beam spot position intervals.
    Type: Application
    Filed: December 21, 2005
    Publication date: July 20, 2006
    Inventors: Shigeaki Imai, Tomohiro Nakajima
  • Multibeam scanning apparatus
    Patent number: 7075688
    Abstract: A multibeam scan apparatus includes a light source having semiconductor laser diodes and coupling lenses arranged in a main scan direction. The semiconductor laser diodes are positioned so that light beams emitted by the semiconductor laser diodes substantially cross each other at a point. A light beam restricting unit shapes the light beams from the laser diodes through the coupling lenses so that the light beams have a given spot size. The light beam restricting unit is positioned close to the above-mentioned point. A scan lens causes the light beams reflected by a polygonal mirror to form images on a scanned surface.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: July 11, 2006
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Image forming apparatus
    Publication number: 20060140667
    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: November 28, 2005
    Publication date: June 29, 2006
    Inventors: Yasushi Nakazato, kazuyuki Shimada, Tomohiro Nakajima
  • Optical scanning device for reducing a dot position displacement at a joint of scanning lines
    Patent number: 7068296
    Abstract: In this optical scanning device, a plurality of scanning optical systems are arranged in a main scanning direction. Each of the scanning optical systems includes a deflecting unit performing an optical scanning by oscillation. Scanning frequencies of the deflecting units are substantially equal to one another. Each of the deflecting units is provided with means for varying the scanning frequency. The scanning frequency of each of the deflecting units is set midway between a maximum value and a minimum value of a resonance frequency intrinsic to the deflecting unit.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: June 27, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Yoshinori Hayashi, Tomohiro Nakajima, Mitsumi Fujii, Yukito Satoh, Eiji Mochizuki
  • Optical-element holding device, method of adjusting shape of optical element, optical-element shape adjusting device, method of correcting scanning line variation, optical scanning device, and image forming apparatus
    Publication number: 20060132880
    Abstract: An optical-element holding device includes an elastic member that presses an optical element with an elastic force in a direction orthogonal to an optical axis of the optical element and orthogonal to a longitudinal direction of the optical element, and a support member that forms a pair with the elastic member and supports the optical element against a pressing force of the elastic member. At least three pairs of the elastic member and the support member are provided.
    Type: Application
    Filed: November 28, 2005
    Publication date: June 22, 2006
    Inventors: Taku Amada, Tomohiro Nakajima, Akihisa Itabashi
  • Image forming apparatus with horizontal structural members
    Patent number: 7050739
    Abstract: An image forming apparatus including a plurality of image forming cartridges and/or a plurality of light emitting members in a housing. Horizontal and/or vertical structural members attached to the housing separate the plurality of image forming cartridges and/or plurality of light emitting members. The horizontal and/or vertical structural members improves rigidity and reduces banding ascribable to the vibration.
    Type: Grant
    Filed: June 10, 2004
    Date of Patent: May 23, 2006
    Assignee: Ricoh Company, Ltd.
    Inventors: Yasushi Nakazato, Kazuyuki Shimada, Tomohiro Nakajima
  • Optical scanning unit and image forming apparatus
    Publication number: 20060028533
    Abstract: An optical scanning unit, includes a light source having a plurality of light emitting sources, a vibration mirror part configured to reciprocatingly scan a light beam emitted from the light source where a torsion bar is a rotational axis, and a recording control part configured to output image information for modulating the light emitting source as corresponding to a scan operation of the vibrating mirror part. Image information corresponding to one line to be recorded is shared by the light sources so that image recording is implemented.
    Type: Application
    Filed: August 3, 2005
    Publication date: February 9, 2006
    Inventor: Tomohiro Nakajima
  • Vibrating mirror, optical scanner using vibrating mirror, and image reproducing and forming apparatus
    Patent number: 6995885
    Abstract: A vibrating mirror comprises a moving mirror configured to deflect a light beam, a torsion bar coupled to the moving mirror and defining a rotational axis of the moving mirror, and a mirror driving part configured to produce a rotational force for causing the moving mirror to oscillate, wherein the torsion bar is coupled to the moving mirror at connecting positions offset from the rotational axis by a distance r/2 in opposite directions so as to satisfy r>A/6, where A is the width of the moving mirror perpendicular to the rotational axis.
    Type: Grant
    Filed: June 29, 2004
    Date of Patent: February 7, 2006
    Assignee: Ricoh Company, Ltd.
    Inventor: Tomohiro Nakajima
  • Vibration mirror, optical scanning device, and image forming using the same, method for making the same, and method for scanning image
    Publication number: 20060012844
    Abstract: A vibration mirror is reciprocatively vibrated by an electrostatic force to reflect an incident light beam.
    Type: Application
    Filed: September 1, 2005
    Publication date: January 19, 2006
    Inventors: Mitsumi Fujii, Yukito Satoh, Tomohiro Nakajima