Patents by Inventor Shigesumi Araki

Shigesumi Araki 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).

  • Publication number: 20110141382
    Abstract: In one embodiment, a liquid crystal shutter includes a first liquid crystal panel for left eye and a second liquid crystal panel for right eye. Each liquid crystal panel includes a pair of electrode substrates and a liquid crystal layer held between the electrode substrates. A driving circuit switches the first and second liquid crystal panels between a transmissive state and a non-transmissive state by turns by applying a voltage to the first and second liquid crystal panels while inversing the polarity of the voltage applied between the pair of the electrode substrates at least once during a period in the transmissive state.
    Type: Application
    Filed: December 10, 2010
    Publication date: June 16, 2011
    Applicant: Toshiba Mobile Display Co., Ltd.
    Inventors: Mitsutaka OKITA, Shigesumi Araki, Emi Higano
  • Publication number: 20110134115
    Abstract: In one embodiment, a display device includes a display panel having pixels. A first image signal for displaying two-dimensional pictures, a second image signal for displaying three-dimensional pictures, and a third image signal for displaying a black picture are written into the pixels. A control circuit writes the third image signal to the pixel of the display panel during at least one frame period when switching a first mode for displaying the two-dimensional pictures and a second mode for displaying the three-dimensional pictures.
    Type: Application
    Filed: December 2, 2010
    Publication date: June 9, 2011
    Applicant: Toshiba Mobile Display Co., Ltd.
    Inventors: Shigesumi Araki, Kazuhiro Nishiyama, Kenji Nakao, Tetsuo Fukami, Toshiyuki Higano, Daiichi Suzuki, Emi Higano
  • Publication number: 20110080535
    Abstract: A liquid crystal shutter includes a first support substrate having a first electrode and a second support substrate having a second electrode opposite to the first electrode. A liquid crystal layer is sandwiched between the first and second electrodes so as to have a switching region. The switching region becomes a bend alignment state from a splay alignment state when a voltage is applied to the liquid crystal layer. A nucleus region formation portion is arranged on the first support substrate to form a nucleus region in the switching region corresponding to the nucleus region formation portion in the liquid crystal layer, in which the splay alignment is more stable than in the switching region.
    Type: Application
    Filed: May 3, 2010
    Publication date: April 7, 2011
    Applicant: Kabushiki Kaisha Toshiba
    Inventors: Tetsuya KOJIMA, Toshiyuki Higano, Shigesumi Araki, Tetsuo Fukami, Kazuhiro Nishiyama
  • Patent number: 7889154
    Abstract: A liquid crystal display apparatus includes a display panel configured to be formed by arranging pixels like a matrix, a light source configured to light the display panel, and a driving control means for controlling the display panel, wherein the pixels are transreflective type liquid crystal pixels having a reflective part and a transmissive part driven independently, and the driving control means is configured to separately control non-image periods of the reflective part and transmissive part.
    Type: Grant
    Filed: July 25, 2007
    Date of Patent: February 15, 2011
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Shigesumi Araki, Kazuhiro Nishiyama, Mitsutaka Okita
  • Patent number: 7868979
    Abstract: A liquid crystal display device includes a liquid crystal display panel to which an OCB mode is applied, and an optical compensation element which optically compensates a retardation of the liquid crystal layer in a predetermined display state in which a voltage is applied to the liquid crystal layer. The optical compensation element includes a polarizer, a first retardation plate which is disposed between the polarizer and the liquid crystal display panel and in which discotic liquid crystal molecules are fixed in a state in which the discotic liquid crystal molecules are hybrid-aligned along a normal direction, and a second retardation plate which is disposed between the polarizer and the first retardation plate and has wavelength dispersion characteristics which are opposite to wavelength dispersion characteristics of an in-plane retardation in the liquid crystal layer.
    Type: Grant
    Filed: November 13, 2008
    Date of Patent: January 11, 2011
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Mitsutaka Okita, Kazuhiro Nishiyama, Shigesumi Araki
  • Patent number: 7868977
    Abstract: Optical compensation elements include first phase plates and second phase plates, which have retardation in a front-plane direction. When a value ?n/?n? is set by normalizing a retardation amount ?n·d relating to light of each of wavelengths by a retardation amount ?n?·d relating to light of a predetermined wavelength ?, a normalized value ?n/?n? in the first phase plate is greater than a normalized value ?n/?n? in a liquid crystal layer, and a normalized value ?n/?n? in the second phase plate is less than the normalized value ?n/?n? in the liquid crystal layer, with respect to light of wavelengths other than the predetermined wavelength.
    Type: Grant
    Filed: May 26, 2006
    Date of Patent: January 11, 2011
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Kenji Nakao, Kazuhiro Nishiyama, Mitsutaka Okita, Daiichi Suzuki, Shigesumi Araki
  • Patent number: 7864156
    Abstract: A liquid crystal display device includes a liquid crystal display panel which periodically performs graduation display and non-graduation display, a backlight which illuminates the liquid crystal display panel, and a light source control circuit which sets an illumination period that allows illumination of the backlight for the gradation display and drives the backlight unit during the illumination period. The light source control circuit is configured to drive the backlight intermittently during the illumination period in limiting the luminance of the backlight.
    Type: Grant
    Filed: May 29, 2007
    Date of Patent: January 4, 2011
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Mitsutaka Okita, Kazuhiro Nishiyama, Shigesumi Araki
  • Publication number: 20100289786
    Abstract: A liquid crystal display device includes a display portion having a first substrate, a second substrate opposing to the first substrate, a liquid crystal layer held between the first and second substrates, and a plurality of pixels arranged in a delta shape. A plurality of pixel electrodes are respectively connected to signal lines extending in a first direction via a switch. The switch is controlled by scanning lines extending in a second direction which orthogonally crosses the first direction. The signal lines extend in a space between the pixel electrodes in a meandering shape in the second direction, and two kinds of color pixels are connected with a common signal line in turn via the pixel switch.
    Type: Application
    Filed: April 30, 2010
    Publication date: November 18, 2010
    Applicant: Toshiba Mobile Display Co., Ltd.
    Inventors: Yukio TANAKA, Tetsuo Fukami, Emi Higano, Shigesumi Araki, Ken Shiiba
  • Patent number: 7817233
    Abstract: In an embodiment of the invention for an OCB (Optically Compensated Bend)-mode liquid-crystal display (LCD) device, retardation and/or a predetermined voltage range, from which a voltage applied to pixels in a viewing area is selected, is set for the each pixel or for the pixels in each region of the viewing area such that: the luminance on each pixel monotonously increases or decreases with increase of voltage in the predetermined voltage range; the luminance in central portion of the viewing area becomes minimum at black displaying.
    Type: Grant
    Filed: December 27, 2006
    Date of Patent: October 19, 2010
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Mitsutaka Okita, Kazuhiro Nishiyama, Daiichi Suzuki, Shigesumi Araki
  • Patent number: 7786969
    Abstract: In an OCB liquid crystal display device, a gradation voltage of a video signal is set to be lower than a black display optimum voltage, and a reverse transition prevention voltage is set to be higher than the black display optimum voltage and to be lower than a maximum applied voltage, and as the gradation voltage of the video signal becomes low, the reverse transition prevention voltage is set to be high.
    Type: Grant
    Filed: November 28, 2006
    Date of Patent: August 31, 2010
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Shigesumi Araki, Kazuhiro Nishiyama, Mitsutaka Okita, Daiichi Suzuki
  • Patent number: 7733322
    Abstract: A liquid crystal display device includes a liquid crystal display panel having pixels, a light source which illuminates the display panel, and a control unit which controls the display panel and the light source. The control unit includes an insertion unit which causes the pixel to store a first voltage corresponding to a video signal in a first period within one frame period and to store a second voltage corresponding to a non-video signal in a second period that follows the first period, and a driving unit which enables the light source at least in a period corresponding to the first period in which the first voltage is held in the pixel, and disables the light source in a period corresponding to the second period in which the second voltage is held in the pixel, and is configured to set the first and second voltages at different independent values.
    Type: Grant
    Filed: November 29, 2006
    Date of Patent: June 8, 2010
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Shigesumi Araki, Kazuhiro Nishiyama, Mitsutaka Okita, Daiichi Suzuki
  • Patent number: 7623202
    Abstract: It is possible to eliminate the blue tone in the black color display in the OCB liquid crystal display device. A liquid crystal display cell (110) includes an opposing substrate (130) having an opposing electrode (Ecom), an array substrate (120) having pixel electrodes of the respective colors (dpixR, dpixG, dpixB), a liquid crystal layer (140) arranged in a bend-arrangement and sandwiched between the opposing substrate (130) and the array substrate (120), and red, green, and blue filter layers (CF(R), CF(G), CF(B)) arranged on one of the substrates. The maximum voltage is applied when performing black color display on the display screen. At least the maximum voltage of the pixel electrode for blue color dpixB applied to the opposing electrode (Ecom) is made different from the maximum voltage of the pixel electrodes of the other colors applied to the opposing electrode (Ecom).
    Type: Grant
    Filed: December 8, 2004
    Date of Patent: November 24, 2009
    Assignee: Toshiba Matsushita Display Technology Co., Ltd
    Inventors: Shigesumi Araki, Kazuhiro Nishiyama, Mitsutaka Okita, Daiichi Suzuki
  • Patent number: 7609340
    Abstract: To reduce the blue tone in the black display of the OCB liquid crystal display device. A liquid crystal display cell (11) includes: an opposing substrate (130) having an opposing electrode (Ecom); an array substrate (120) having a pixel electrode Dpix for each color; a liquid crystal layer (140) arranged in a bend arrangement located between the opposing substrate (120) and the array substrate (120); and red, green, and blue filter layers arranged on one of the substrates. The opposing electrode has a film thickness tB of the portion Ecom (B) corresponding to the blue filter layer, which thickness is set so as to have the minimum value in the range 380 nm to 480 nm in the spectrum of the front reflectance and satisfy the following: 100 nm<tB?140 nm.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: October 27, 2009
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Daiichi Suzuki, Kazuhiro Nishiyama, Mitsutaka Okita, Shigesumi Araki
  • Publication number: 20090066899
    Abstract: A liquid crystal display device includes a liquid crystal display panel to which an OCB mode is applied, and an optical compensation element which optically compensates a retardation of the liquid crystal layer in a predetermined display state in which a voltage is applied to the liquid crystal layer. The optical compensation element includes a polarizer, a first retardation plate which is disposed between the polarizer and the liquid crystal display panel and in which discotic liquid crystal molecules are fixed in a state in which the discotic liquid crystal molecules are hybrid-aligned along a normal direction, and a second retardation plate which is disposed between the polarizer and the first retardation plate and has wavelength dispersion characteristics which are opposite to wavelength dispersion characteristics of an in-plane retardation in the liquid crystal layer.
    Type: Application
    Filed: November 13, 2008
    Publication date: March 12, 2009
    Inventors: Mitsutaka OKITA, Kazuhiro NISHIYAMA, Shigesumi ARAKI
  • Publication number: 20090002310
    Abstract: A liquid crystal display apparatus in an embodiment of the invention, in which each frame period is divided into a first period for writing the non-video signals, a second period for writing the video signals to the respective pixels, and a third period for maintaining the video signals in the respective pixels; and in which a control unit (1) calculates a backlight luminance value and gamma conversion values based on the distribution of the gradation values prior to the second period, (2) gamma-converts the input video signals based on the gamma conversion values and writes gamma-converted video signals into the respective pixels during the second period, (3) causes the backlight to emit light based on the backlight luminance value during the third period.
    Type: Application
    Filed: June 24, 2008
    Publication date: January 1, 2009
    Applicant: Toshiba Matsushita Display Technology Co., Ltd
    Inventors: Seiji Kawaguchi, Shigesumi Araki, Kazuhiro Nishiyama, Kenji Nakao, Ken Shiiba
  • Publication number: 20090002578
    Abstract: A projection system which has a plurality of liquid-crystal displays each includes a display panel having a plurality of OCB-mode liquid-crystal pixels, and a control unit configured to control the display panel, and which synthesizes images of different colors, modulated by the display panels, thereby to display a color image, wherein each of the liquid-crystal displays includes a temperature sensor, and the control unit of each liquid-crystal display controls at least one condition of driving the display panel in accordance with the temperature detected by any one of the temperature sensors.
    Type: Application
    Filed: June 27, 2008
    Publication date: January 1, 2009
    Inventors: Shigesumi ARAKI, Kenji NAKAO, Kazuhiro NISHIYAMA
  • Publication number: 20090002609
    Abstract: A liquid crystal display device having a reflective part and a transmissive part in each of a plurality of pixels which are arrayed in a matrix, includes a liquid crystal display panel which is configured such that a liquid crystal layer is held between a pair of substrates, and to which an OCB mode is applied, and a pair of optical elements which are disposed on outer surfaces of the liquid crystal display panel, respectively, and optically compensate a retardation of the liquid crystal layer in a predetermined display state in which a voltage is applied to the liquid crystal layer, wherein the optical element is configured to include a circular polarization element including a polarizer and a first retardation plate which is disposed between the polarizer and the liquid crystal display panel and imparts a retardation of 1/4 wavelength, and a second retardation plate which is disposed between the circular polarization element and the liquid crystal layer, and has refractive index anisotropy with a major axis
    Type: Application
    Filed: May 15, 2008
    Publication date: January 1, 2009
    Inventors: Mitsutaka Okita, Kazuhiro Nishiyama, Shigesumi Araki, Emi Higano
  • Publication number: 20080291372
    Abstract: A transflective liquid crystal display device includes a liquid crystal display panel which is configured such that a liquid crystal layer is held between a pair of substrates, and to which an OCB mode is applied, and a pair of optical elements which are disposed on outsides of the liquid crystal layer, and optically compensate a retardation of the liquid crystal layer in a predetermined display state in which a voltage is applied to the liquid crystal layer, wherein the optical element is configured to include a circular polarization element including a polarizer and a first retardation plate which imparts a retardation of ¼ wavelength, and the first retardation plate has such wavelength dispersion characteristics as to establish a relationship, ?1<1, where ?1 is a ratio of an in-plane retardation Re430 at a wavelength of 430 nm to an in-plane retardation Re550 at a wavelength of 550 nm.
    Type: Application
    Filed: May 15, 2008
    Publication date: November 27, 2008
    Inventors: Emi HIGANO, Kazuhiro Nishiyama, Mitsutaka Okita, Shigesumi Araki
  • Publication number: 20080291152
    Abstract: A liquid crystal display apparatus includes a display panel in which liquid crystal pixels, which are composed with use of an OCB mode liquid crystal, are arranged in a matrix, first and second backlights which illuminate the display panel, and driving control means for controlling the display panel, wherein light from the first backlight is emitted with an inclination of a predetermined angle in a first direction to a plane which is perpendicular to a display surface of the display panel and extends along an alignment direction of liquid crystal molecules, and light from the second backlight is emitted with an inclination of the predetermined angle to the plane, the first direction and the second direction being symmetric to each other with regard to the plane.
    Type: Application
    Filed: May 19, 2008
    Publication date: November 27, 2008
    Inventors: Kenji NAKAO, Yukio Tanaka, Shigesumi Araki, Kazuhiro Nishiyama
  • Patent number: 7443468
    Abstract: A liquid crystal display cell (110) includes: an opposing substrate (130) having an opposing electrode (Ecom); an array substrate (120) having a pixel electrode Dpix for each color; a liquid crystal layer (140) arranged in a bend arrangement located between the opposing substrate (120) and the array substrate (120); and red, green, and blue filter layers (CF(R), CF(G), CF(B)) arranged on one of the substrates. Distances (dB, dG, dR) between the pixel electrodes of the respective colors (dpixR, dpixG, dpixB) and the opposing electrode (Ecom) are set as follows: dB<dR, dB.
    Type: Grant
    Filed: October 21, 2004
    Date of Patent: October 28, 2008
    Assignee: Toshiba Matsushita Display Technology Co., Ltd.
    Inventors: Mitsutaka Okita, Kazuhiro Nishiyama, Daiichi Suzuki, Shigesumi Araki