Patents by Inventor Hideyuki Kawagishi

Hideyuki Kawagishi 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: 5158619
    Abstract: A photoconductive device employs an organic film between a pair of electrodes where the organic film is a polymer having a carbazole skeleton and an imide linkage in a repeating unit of the general formula: ##STR1## where R.sup.1 denotes a tetravalent organic group having 5 to 13 carbons.
    Type: Grant
    Filed: April 9, 1991
    Date of Patent: October 27, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Haruki Kawada, Yoshihiro Yanagisawa, Yuko Morikawa, Suomi Kurihara, Hiroshi Matsuda, Hideyuki Kawagishi, Kiyoshi Takimoto
  • Patent number: 5136282
    Abstract: A ferroelectric liquid crystal apparatus of the matrix type which includes a display portion provided with separate display areas which are arranged to be independently driven and a method of driving such a ferroelectric liquid crystal apparatus. In the method, dummy signals are applied to signal electrodes of one of the separate display areas while the other display area is being scanned in order to reduce differences in contrast.
    Type: Grant
    Filed: December 14, 1989
    Date of Patent: August 4, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yutaka Inaba, Hiroyuki Kitayama, Hideyuki Kawagishi
  • Patent number: 5082352
    Abstract: A ferroelectric liquid crystal apparatus includes: a ferroelectric liquid crystal cell including a pair of substrates each having an electrode and an alignment film thereon, the alignment films being respectively provided with uniaxial orientation axes (preferably those provided by rugging) which are provided in parallel and in the same oblique direction of from upper right to lower left or from lower left to upper right [from lower right to upper left or from upper left to lower right], a first polarizer having a transmission axis set within a region (I) defined by a clockwise (or counterclockwise) angle of 45.degree. from the direction of the uniaxial orientation axes, a second polarizer having a transmission axis set within a region (II) defined by a clockwise (or counter-clockwise) angle of 45.degree.
    Type: Grant
    Filed: September 27, 1989
    Date of Patent: January 21, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideyuki Kawagishi, Hirofumi Iwamoto, Yoshihiro Onitsuka
  • Patent number: 5035491
    Abstract: A liquid crystal apparatus, comprising: a liquid crystal cell comprising a pair of substrates, and a chiral smectic liquid crystal showing at least two different optically stable states formed by cooling from a uniaxial alignment phase and disposed between the substrates; and a polarizer and an analyzer disposed to sandwiched the liquid crystal cell; wherein the chiral smectic liquid crystal, polarizer and analyzer are disposed to satisfy any one of the following sets of conditions I-IV characterized by combination of X, Y and Z directions shown below:______________________________________ X Y Z ______________________________________ I clockwise counterclockwise perpendicular II clockwise clockwise parallel III counterclockwise counterclockwise parallel IV counterclockwise clockwise perpendicular ______________________________________with proviso that the chiral smectic liquid crystal is disposed so that the long axes of the chiral smectic liquid crystal molecules are aligned with a twist in the X direction a
    Type: Grant
    Filed: April 3, 1990
    Date of Patent: July 30, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideyuki Kawagishi, Hirofumi Iwamoto, Akira Tsuboyama, Tadashi Mihara
  • Patent number: 5026144
    Abstract: A liquid crystal device, comprises: a pair of opposite electrodes and a ferroelectric liquid crystal showing a first and a second alignment state depending on the direction of an electric field applied thereto and disposed between the opposite electrodes. The ferroelectric liquid crystal is placed in a stated of causing a relaxation such that, when a voltage pulse equal to the threshold is applied between the opposite electrodes, the ferroelectric liquid crystal causes a change in its molecular alignment state from one molecular alignment state toward the other molecular alignment state and continues the change in its molecular alignment state even after the removal of the voltage pulse until the change reaches a saturation in a certain period.
    Type: Grant
    Filed: January 22, 1990
    Date of Patent: June 25, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Osamu Taniguchi, Hideyuki Kawagishi, Akira Tsuboyama, Shinjiro Okada, Yutaka Inaba, Junichiro Kanbe
  • Patent number: 5013137
    Abstract: A ferroelectric liquid crystal device comprising a pair of substrates each provided with an electrode thereon, and a ferroelectric liquid crystal layer disposed between the substrates in a thickness which is thin enough to release the spiral structure of the ferroelectric liquid crystal, wherein the ferroelectric liquid crystal provides two average molecular axis directions forming an angle 2.theta. therebetween, each average molecular axis direction corresponding to one or two stable orientation states of the ferroelectric liquid crystal, the ferroelectric liquid crystal provides two average molecular axis directions forming an angle 2 .circle.H therebetween when voltages exceeding the threshold voltage of the ferroelectric liquid crystal are applied to the ferroelectric liquid crystal, and the ferroelectric liquid crystal provides two average molecular directions forming an angle 2.theta.
    Type: Grant
    Filed: February 2, 1989
    Date of Patent: May 7, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akira Tsuboyama, Yutaka Inaba, Hiroyuki Kitayama, Shinjiro Okada, Osamu Taniguchi, Hideyuki Kawagishi, Yukio Hanyu
  • Patent number: 5005953
    Abstract: A liquid crystal element has a pair of substrates including electrodes and uniaxial orientation-processing axes, a ferroelectric smectic liquid crystal having a temperature range for producing a smectic A phase, under an orientation state having at least two different average molecular axes disposed between the pair of substrates which are set at a distance sufficiently small for suppressing a spiral alignment structure of the ferroelectric smectic liquid crystal on the occasion of no field application, and a polarizer and an analyzer. The ferroelectric smectic liquid crystal, on the occasion of being set within a temperature range for a smectic A phase, produce a .vertline.T.sub.A -T.sub.B .vertline.
    Type: Grant
    Filed: November 20, 1989
    Date of Patent: April 9, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hideyuki Kawagishi
  • Patent number: 4958915
    Abstract: A liquid crystal apparatus, comprising a liquid crystal panel comprising a plurality of scanning lines, and a plurality of picture elements disposed along each of the scanning lines and comprising a ferroelectric liquid crystal; a backlight disposed behind the liquid crystal panel for illuminating the liquid crystal panel, the backlight changing the light quantity emitted therefrom with the elapse of time. The liquid crystal apparatus is so driven that the low level of the light quantity of the backlight is synchronized with a time when a writing signal is applied to picture elements on at least one scanning line.
    Type: Grant
    Filed: February 13, 1989
    Date of Patent: September 25, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinjiro Okada, Tohru Takahashi, Hideyuki Kawagishi, Yutaka Inaba, Osamu Taniguchi
  • Patent number: 4958912
    Abstract: An image forming apparatus includes a light source; an optical shutter unit comprising a pair of parallel substrates respectively having a plurality of scanning electrodes and a plurality of data electrodes disposed to intersect with each other to form a matrix electrode structure on their opposite surfaces, and a ferroelectric liquid crystal disposed between the pair of substrates so as to form a microshutter at each intersection of the scanning electrodes and data electrodes; an optical system for forming an image at a desired position with light transmitted through the optical shutter unit; a photosensitive member as a medium for recording the thus formed image; a scanning side drive circuit for applying a scanning voltage signal to the plurality of scanning electrodes so as to sequentially select at least one scanning electrode in a prescribed cycle; and a data side drive unit for applying data voltage signals to the plurality of data electrodes in synchronism with said scanning voltage signal.
    Type: Grant
    Filed: July 6, 1988
    Date of Patent: September 25, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yutaka Inaba, Hideyuki Kawagishi, Makoto Kojima, Shuzo Kaneko
  • Patent number: 4932758
    Abstract: A ferroelectric smectic liquid crystal device having an improved impact resistance and an improved contrast is provided by using a pair of substrates provided with uniaxial alignment axes which are parallel and identical in direction with each other. A ferroelectric smectic liquid crystal is disposed between the pair of substrates so as to assume a higher-temperature alignment state and a lower-temperature alignment state on temperature decrease in its ferroelectric smectic phase placed in a bistable alignment state. The ferroelectric smectic liquid crystal is further placed in the lower-temperature alignment state which is characterized by having an inclination of forming a connected pair of a lightning defect and a hair pin defect coming after the lightning defect.
    Type: Grant
    Filed: September 16, 1988
    Date of Patent: June 12, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yukio Hanyu, Junichiro Kanbe, Hideyuki Kawagishi, Yutaka Inaba
  • Patent number: 4883344
    Abstract: A liquid crystal device comprises a pair of parallel substrates and a ferroelectric liquid crystal disposed between the substrates so as to have an arrangement of molecules forming a plurality of layers perpendicular to the faces of the substrates. At least one of the pair of substrates has an alignment control film formed of a modified polyvinyl alcohol resin having a function of aligning said plurality of layers preferentially in one direction. The modified polyvinyl alcohol resin film stably provides a uniform alignment state with a large tilt angle than a conventional alignment control film of polyimide or unmodified polyvinyl alcohol.
    Type: Grant
    Filed: January 24, 1989
    Date of Patent: November 28, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinjiro Okada, Kazuo Yoshinaga, Osamu Taniguchi, Hideyuki Kawagishi, Akira Tsuboyama, Yukio Hanyu, Masataka Yamashita, Kazuharu Katagiri
  • Patent number: 4820026
    Abstract: A liquid crystal device comprises a pair of parallel substrates and a ferroelectric liquid crystal disposed between the substrates so as to have an arrangement of molecules forming a plurality of layers perpendicular to the faces of the substrates. At least one of the pair of substrates has an alignment control film formed of a modified polyvinyl alcohol resin having a function of aligning said plurality of layers preferentially in one direction. The modified polyvinyl alcohol resin film stably provides a uniform alignment state with a larger tilt angle than a conventional alignment control film of polyimide or unmodified polyvinyl alcohol.
    Type: Grant
    Filed: March 17, 1987
    Date of Patent: April 11, 1989
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinjiro Okada, Kazuo Yoshinaga, Osamu Taniguchi, Hideyuki Kawagishi, Akira Tsuboyama, Yukio Hanyu, Masataka Yamashita, Kazuharu Katagiri