Exposure Adjustment Patents (Class 399/198)
  • Patent number: 8896643
    Abstract: An image forming apparatus including: a photoreceptor; a charger configured to charge a photoreceptor surface; an optical scanning device configured to expose the photoreceptor surface to form an electrostatic latent image thereon; a developing device configured to develop the electrostatic latent image to form a toner image thereon; a transfer member configured to transfer the toner image to a sheet; a fixing device configured to fix the toner image thereon; and a control unit configured to carry out exposure amount control for formation of an image having a pattern with a spatial frequency from 0.1 c/mm to 3.0 c/mm so that after the exposure, there will be an electric potential difference V1 between an edge portion and a non-edge portion of the pattern and so that there will be an electric potential difference V2 larger than V1 between an edge-surrounding portion and the other portions of a non-image area.
    Type: Grant
    Filed: December 30, 2013
    Date of Patent: November 25, 2014
    Assignee: Konica Minolta, Inc.
    Inventor: Yohei Nakade
  • Patent number: 8737871
    Abstract: An electrophotographic image forming apparatus includes a cartridge tray movable between an inside position and an outside position of a main body of the apparatus with supporting a cartridge, a light emitting member having a plurality of light emitting elements for emitting light to expose a photosensitive member in accordance with image information, and a support that supports the light emitting member between an exposure position at which the photosensitive member is exposed with the light emitting element and a retracted position retracted from the exposure position. In addition, an interlocking device moves the support between the exposure position and the retracted position in association with movement of the tray toward the outside and inside positions.
    Type: Grant
    Filed: January 21, 2010
    Date of Patent: May 27, 2014
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tetsuji Suzuki
  • Patent number: 8208171
    Abstract: The present invention aims to prevent a problem that an image on a document sheet is erased due to misdetection of a line-shaped noise. A copy machine 1 compares RGB values of a target pixel with averaged RGB values (Step S103). If only one of the RGB values has a difference that is greater than a prescribed value Ref2 (Step S103: YES), the copy machine 1 extracts the target pixel as a line-shaped noise pixel, and moves to a line-shaped noise correction (Step S108) while holding the address of the target pixel in a line-shaped noise address storing area 49b. If two of the RGB values have differences (Step S103: NO, Step S104: YES) and a difference between these two of the RGB values is no greater than a prescribed value Ref3 (Step S105: YES), the copy machine 1 extracts the target pixel as a line-shaped noise pixel, and moves to the line-shaped noise correction (Step S108) while holding the address of the target pixel in the line-shaped noise address storing area 49b.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: June 26, 2012
    Assignee: Konica Minolta Business Technologies, Inc.
    Inventors: Hiroaki Kubo, Nobuhiro Mishima
  • Patent number: 8010000
    Abstract: An image forming apparatus includes a light source unit, an image carrier on which a latent image is formed by a light beam emitted from a light source, a developing unit configured to develop a latent image formed on the image carrier using a toner, an intermediate transfer unit on which a toner image developed by the developing unit is transferred, a heating unit configured to heat the intermediate transfer unit on which a toner image is transferred, a fixing unit configured to fix the toner image heated by the heating unit on a recording medium, a temperature detection unit configured to detect temperature of the intermediate transfer unit, and a control unit configured to control a magnification of a latent image to be formed on the image carrier according to a detection result of the temperature detection unit.
    Type: Grant
    Filed: July 9, 2008
    Date of Patent: August 30, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tatsuya Goto
  • Patent number: 7903990
    Abstract: In a development device which develops an electrostatic image formed on a rotating photosensitive drum by applying a development bias to a development sleeve bearing a two-component developer, the development device includes a specific pattern determination portion which determines whether or not the electrostatic image includes a specific pattern. When the development device develops the specific pattern electrostatic image determined by the specific pattern determination portion, a potential difference between a development sleeve and a first non-image part of a predetermined range which is adjacent to the specific pattern electrostatic image and located on an upstream side in a photosensitive drum rotating direction is set smaller than a potential difference between the development sleeve and a second non-image part which is different from the first non-image part.
    Type: Grant
    Filed: June 24, 2008
    Date of Patent: March 8, 2011
    Assignee: Canon Kabushiki Kaisha
    Inventor: Yuji Bessho
  • Patent number: 7859714
    Abstract: A light emitting device that forms a latent image by irradiating light onto a charged surface of an image carrier. The light emitting device includes an electro-optical substrate that forms an optical image, a focusing lens array that focuses light from the electro-optical substrate to form an erect image of the corresponding optical image on the charged surface, and a frame in which the focusing lens array is fixed. A position determining member, which is formed of resin, is disposed on the frame, comes in contact with a supporting body that supports the image carrier, and determines a distance between the focusing lens array and the image carrier by its own height.
    Type: Grant
    Filed: August 2, 2006
    Date of Patent: December 28, 2010
    Assignee: Seiko Epson Corporation
    Inventor: Kazunori Sakurai
  • Patent number: 7536125
    Abstract: A line sensor that detects the edge position of a recording paper is provided on the upstream side of a transfer point where an image formed on a first photosensitive drum is transferred to the recording paper. When performing borderless image formation, the size of the image on the first photosensitive drum to be transferred to the midstream of the recording paper after detection of its edge position is changed to a smaller size based on the detection results by the line sensor, and subsequent image formation to the recording paper continues to be performed according to this image on the photosensitive drum whose size has been changed.
    Type: Grant
    Filed: April 30, 2004
    Date of Patent: May 19, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masanobu Yamamoto, Hidenobu Mandai, Masahiko Fujita, Takayuki Ohno, Masaki Saka, Kouzou Yamaguchi, Osamu Fujimoto, Masaya Asakawa
  • Patent number: 6853816
    Abstract: An image forming apparatus includes, a first speed decision unit which decides the driving speed of a drive source of a unit for printing, a magnification adjustment unit which adjusts the magnification of image information by changing the speed of the first speed decision unit, a second speed decision unit which decides the driving speed of a drive source of a carry unit to carry a printing medium, and a speed change interlock unit which changes the speed of the second speed decision unit, when the speed of the first speed decision unit is changed by the magnification adjustment unit.
    Type: Grant
    Filed: April 24, 2003
    Date of Patent: February 8, 2005
    Assignees: Kabushiki Kaisha Toshiba, Toshiba Tec Kabushiki Kaisha
    Inventor: Shungo Miyata
  • Patent number: 6032009
    Abstract: In an image reading apparatus, an image is illuminated to be guided as a light beam to a photosensitive drum through an image forming lens. Light amount correcting members are attached to a movable member movably attached relatively to the image forming lens. The movable member moves in the optical axis direction in accordance with movement of the image forming lens, and one of the light amount correcting members farther from the image forming lens is caused to face a corresponding surface of the image forming lens so as to intercept a part of the light beam from the image in association with the movement of the movable member. The other of the light amount correcting members closer to the image forming lens is caused to retract from a corresponding surface of the image forming lens in association with the movement of the movable member.
    Type: Grant
    Filed: September 8, 1998
    Date of Patent: February 29, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Nobumasa Fukuzawa, Yoshiyuki Koshimizu
  • Patent number: 6025933
    Abstract: According to an image pickup apparatus of this invention, a light source illuminates an object, an image pickup unit picks up an image of the illuminated object, an amplifier circuit amplifies the output signal for the image pickup unit, and a control unit adjusts the light amount of the light source after setting the maximum gain of the amplifier circuit and controls the image pickup unit to pickup the image of the object. An image pickup operation can be performed by irradiating an object with a minimum amount of light that the circuitry is capable of coping with.
    Type: Grant
    Filed: October 14, 1997
    Date of Patent: February 15, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventor: Kazuhito Ohashi