Patents by Inventor Tatsundo Kawai

Tatsundo Kawai 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: 6239421
    Abstract: A rod lens array, used in an image sensor, is configured by sandwiching a plurality of rod lenses with two side plates. Among the two side plates, the one which is on the side of the illumination device is made thinner than the other side plate.
    Type: Grant
    Filed: June 12, 1998
    Date of Patent: May 29, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Nagata, Tatsundo Kawai, Masami Tabata
  • Patent number: 6181442
    Abstract: For preventing occurrence of interference fringes derived from interference of light rays on a contact plane between a contact glass and a cover glass, and thus homogenizing an output wave that may otherwise undergo the adverse effect of interference fringes, a close-contact type image sensor includes a contact glass arranged to come into contact with a read surface of an original, a light source for irradiating light to the read surface, an image forming lens for converging light reflected from the read surface, an image sensor part for reading an image of the original formed on an image plane of the image forming lens, and a cover glass for fixing the light source and the image forming lens at respective predetermined positions in a housing, wherein an air layer is present between the contact glass and the cover glass.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: January 30, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Ogura, Tatsundo Kawai
  • Patent number: 6122105
    Abstract: In an image reading device in which an original is illuminated by a light source, and a reflected beam from the original is imaged on a sensor through a rod lens array, a light-shielding member is arranged between the beam exit surface of the light source and the incident surface of the rod lens array to prevent the beam from the light source from being directly incident on the rod lens array to cause a flare. An image reading device and information processing apparatus in which the image quality is rarely degraded by the flare beam are provided.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: September 19, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Masami Tabata
  • Patent number: 6115187
    Abstract: In an image sensor having a photoelectric conversion element for receiving light, an illumination unit, and a lens array in which a plurality of gradient index lens elements for focusing light reflected by an original onto the photoelectric conversion element are arrayed, part of the peripheral portion of the lens of the gradient index lens element in the radius direction contains a light absorber for absorbing light having a predetermined wavelength other than the wavelength distribution of light emitted by the illumination unit.
    Type: Grant
    Filed: October 26, 1998
    Date of Patent: September 5, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masami Tabata, Tatsundo Kawai
  • Patent number: 6055072
    Abstract: In an image sensor which has a photoelectric conversion element group, an illumination device having light sources of at least three emission colors R, G, and B, an imaging lens, and the like, moire noise in a color output image is eliminated, the original reading time is shortened, and a cost reduction is attained. For this purpose, a sensor array (1) including a linear array of a plurality of photoelectric conversion elements, a lens array (2) for imaging an original image on the sensor array (1), an illumination device (3) using LEDs having emission colors R, G, and B, and a cover glass (4) are supported by and fixed to a frame (5). The conjugate length of the lens array (2) is set to fall within the range between the B and G emission wavelengths. An original pressed against the cover glass (4) is illuminated by the illumination device (3), and light reflected by the original is converted into electrical signals by the sensor array (1), thereby reading the original image.
    Type: Grant
    Filed: July 25, 1997
    Date of Patent: April 25, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masami Tabata, Tatsundo Kawai
  • Patent number: 5905583
    Abstract: There is disclosed an illumination device in which a light guide is adapted to emit the light from a face thereof and is provided with an area, on a face opposite to the light emitting face, for diffusing and/or reflecting the light introduced into the light guide from an end face thereof or is provided with uneven light emitting characteristics along the longitudinal direction of the light guide, and the center of the light source positioned at the end of the light guide is placed at a position aberrated from the normal line to the area, whereby attained are compactness, a low cost, a low electric power consumption, a high efficiency of utilization of the light emitted by the light source, and excellent and uniform illumination characteristics. There are also disclosed an image reading device and an information processing apparatus, equipped with the above-mentioned illumination device.
    Type: Grant
    Filed: December 3, 1997
    Date of Patent: May 18, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Osamu Hamamoto, Shinichi Takeda, Satoshi Itabashi
  • Patent number: 5900622
    Abstract: A photoelectric conversion apparatus is constructed in such an arrangement that a light-source substrate, in which a light source is arranged, and a photosensor are directly mounted on a frame bearing the strength of the main body of an information processing apparatus, the above light-source substrate may be unified with an electric circuit substrate of the information processing apparatus, and the electric circuit substrate has the photosensor and the light source, whereby the size and weight of the apparatus can be further decreased, the freedom of design and engineering design can be improved, and simplification of assembling and improvement in reliability can be achieved.
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: May 4, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Ogura, Tatsundo Kawai, Toshihiro Saika
  • Patent number: 5717502
    Abstract: An image reading device having a substrate, an array of a plurality of photoelectric conversion elements arranged on the substrate in a main scanning direction, and a plurality of light emission sources arranged in the main scanning direction to emit light for illumination of an original through light transmission windows formed at one side of the photoelectric conversion element array in a sub scanning direction. A shading portion is provided on the photoelectric conversion element side in each light transmission window corresponding to one of the plurality of photoelectric conversion elements to section the light transmission window into a plurality of light transmission regions at least on the photoelectric conversion element side. This image reading device is thus arranged to provide uniform output from the photoelectric conversion elements at the time of reading a black original.
    Type: Grant
    Filed: October 25, 1994
    Date of Patent: February 10, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tatsundo Kawai
  • Patent number: 5499112
    Abstract: There is disclosed an illumination device in which a light guide is adapted to emit the light from a face thereof and is provided with an area, on a face opposite to the light emitting face, for diffusing and/or reflecting the light introduced into the light guide from an end face thereof or is provided with uneven light emitting characteristics along the longitudinal direction of the light guide, and the center of the light source positioned at the end of the light guide is placed at a position aberrated from the normal line to said area, whereby attained are compactness, a low cost, a low electric power consumption, a high efficiency of utilization of the light emitted by the light source, and excellent and uniform illumination characteristics. There are also disclosed an image reading device and an information processing apparatus, equipped with the above-mentioned illumination device.
    Type: Grant
    Filed: January 19, 1994
    Date of Patent: March 12, 1996
    Assignee: Cannon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Osamu Hamamoto, Shinichi Takeda, Satoshi Itabashi, Toshimitsu Iso
  • Patent number: 5272548
    Abstract: A photosensor with improved correction of image signals has a first photosensor portion including a plurality of photoelectric converting devices for reading an object and providing image signals thereof. A second photosensor portion includes a plurality of photoelectric converting devices and provides reference signals from light reflected from a reference member, or light received directly from a light source. Correction circuitry corrects the image signals from the first photosensor portion in accordance with the reference signals output from the second photosensor portion. Preferably, the photoelectric converting devices of the first and second photosensor portions are arranged in adjacent, parallel lines on the same substrate. Preferably, reference signals from the converting devices of the second photosensor are used by the correction circuitry to correct the electrical signals from substantially adjacent converting devices of the first photosensor portion.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: December 21, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Toshihiro Saika, Noriyuki Kaifu, Isao Kobayashi, Tadao Endo, Kouji Tomoda
  • Patent number: 5261013
    Abstract: A photoelectric converter includes a transparent substrate having a photoelectric converting element provided on a surface opposing a document relating to reading of image information, a transparent support for supporting the substrate, and a light source provided on a surface of the support opposite to a supporting surface for the substrate. Light emitted from the light source is radiated on a document through the support and the substrate, and reflected light is received by the photoelectric converting element.
    Type: Grant
    Filed: March 3, 1992
    Date of Patent: November 9, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masayoshi Murata, Katsumi Komiyama, Tatsundo Kawai, Makoto Ogura, Hiroo Ichihashi, Osamu Hamamoto
  • Patent number: 5233442
    Abstract: A photosensor with improved correction of image signals has a first photosensor portion including a plurality of photoelectric converting devices for reading an object and providing image signals thereof. A second photosensor portion includes a plurality of photoelectric converting devices and provides reference signals from light reflected from a reference number, or light received directly from a light source. Correction circuitry corrects the image signals from the first photosensor portion in accordance with the reference signals output from the second photosensor portion. Preferably, the photoelectric converting devices of the first and second photosensor portions are arranged in adjacent, parallel lines on the same substrate. Preferably, reference signals from the converting devices of the second photosensor are used by the correction circuitry to correct the electrical signals from substantially adjacent converting devices of the first photosensor portion.
    Type: Grant
    Filed: August 19, 1992
    Date of Patent: August 3, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Toshihiro Saika, Noriyuki Kaifu, Isao Kobayashi, Tadao Endo, Kouji Tomoda
  • Patent number: 5204762
    Abstract: An image reading device having a translucent substrate and plural photoelectric converting elements arranged thereon, comprises opaque areas formed in the translucent areas of the translucent substrate in the vicinity of the photoelectric converting elements for the purpose of transmitting a uniform amount of light for each photoelectric converting element.
    Type: Grant
    Filed: August 10, 1992
    Date of Patent: April 20, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tatsundo Kawai
  • Patent number: 5187595
    Abstract: Apparatus for improving illumination in a photoelectric conversion device having a light source for illuminating an original, and at least one photoelectric conversion element for receiving light reflected from the original includes a light guide for guiding light from the light source to the original, the light guide having at least one side surface. A correction section is provided and is disposed adjacent the side surface of the light guide. The correction section acts to suppress total reflection of at least a portion of the light emitted from the light source. Preferably, the correction section comprises regularly spaced light absorbing or light diffusing elements formed on the side of the light guide. The improvement apparatus may be employed in an information processing apparatus such as a facsimile machine.
    Type: Grant
    Filed: November 21, 1990
    Date of Patent: February 16, 1993
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masashi Kitani, Tatsundo Kawai, Hiroo Ichihashi
  • Patent number: 5121225
    Abstract: A photoelectric converter includes a transparent substrate having a photoelectric converting element provided on a surface opposing a document relating to reading of image information, a transparent support for supporting the substrate, and a light source provided on a surface of the support opposite to a supporting surface for the substrate. Light emitted from the light source is radiated on a document through the support and the substrate, and reflected light is received by the photoelectric converting element.
    Type: Grant
    Filed: February 20, 1990
    Date of Patent: June 9, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masayoshi Murata, Katsumi Komiyama, Tatsundo Kawai, Makoto Ogura, Hiroo Ichihashi, Osamu Hamamoto
  • Patent number: 5101285
    Abstract: A photoelectric conversion device includes a photosensor including a plurality of photoelectric conversion elements and a substrate having a transparent portion for transmitting light for illuminating an original bearing information and provided with the plurality of photoelectric conversion elements, and a light source for emitting light for illuminating the original in which a plurality of light-emitting sources are arranged. The device further includes a light diffuser between the photosensor and the light source.
    Type: Grant
    Filed: July 23, 1990
    Date of Patent: March 31, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Tetsuya Shimada, Masashi Kitani, Osamu Hamamoto
  • Patent number: 5063462
    Abstract: An LED array has a plurality of LED blocks each of which can independently be illuminated or extinguished. The LED array includes an illumination control unit for illuminating, after the lapse of a time period T1 after a block is illuminated, a succeeding block; an extinguishment control unit for extinguishing, after the lapse of a time period T2 after a block is illuminated, another block which has been illuminated since before the former block was illuminated; and a time control unit for determining the time period T2. The time control unit is adapted to automatically control the time period T2 in accordance with the outputs from a line sensor which reads out an original image illuminated by the LED array.
    Type: Grant
    Filed: December 5, 1989
    Date of Patent: November 5, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Katsumi Nakagawa, Tatsundo Kawai, Yasuo Kuroda
  • Patent number: 4996606
    Abstract: An image reading apparatus comprises a light emitting device for illuminating an original including information to be read; image sensor for inputting an optical information and converting it into an electric signal; and wherein the light emitting device has a xeron glow lamp and a light source which can illuminate a vicinity of a main electrode of the glow lamp.
    Type: Grant
    Filed: November 14, 1988
    Date of Patent: February 26, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tatsundo Kawai, Makoto Ogura, Koji Tomoda, Hiroo Ichihashi, Shinichi Seitoh, Yasuo Kuroda, Hiroyuki Noguchi
  • Patent number: 4926058
    Abstract: An image reading apparatus in which a plurality of light sources are provided and the lights emitted from the light sources are incident on to photoelectric converting means from an object to be read, thereby reading an image of the object; and dividing the light sources into a plurality of blocks, for sequentially divisionally lighting on the light sources every block, and for lighting on, in a pulse-like manner, the light sources of the blocks which are not divisionally lit on.
    Type: Grant
    Filed: January 23, 1987
    Date of Patent: May 15, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hirofumi Iwamoto, Tatsundo Kawai, Makoto Ogura, Katsumi Nakagawa, Shinichi Seitoh, Noriyuki Kaifu
  • Patent number: 4920431
    Abstract: There is an image reading apparatus for use in a facsimile apparatus, a copying machine or the like. This apparatus illuminates the light from a light source such as an LED array onto an original which is conveyed by a conveying device and thereby reading an image data on the original. To smoothly guide the edge of the original, an original guiding device which guides the original non-rippingly is provided downstream of the position where the original is read in the original conveying direction by the conveying device. As an original guiding device, a flat or concave guide surface, a flat or concave notch, original guide rollers, a guide member having a concave surface, or the like is provided. The guiding device may if desired be light-reflective.
    Type: Grant
    Filed: January 11, 1988
    Date of Patent: April 24, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Ogura, Tatsundo Kawai, Katsuhiko Yamada, Shinichi Seito