Patents by Inventor Mari Sugawara

Mari Sugawara 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: 8134661
    Abstract: To suppress a decrease in the contrast caused by the reflection on the interface to the air layer without decreasing the quality of display. A reflection-type liquid crystal display device includes a light guide plate having a polarizing element stuck or adhered thereto on the side facing a reflection-type liquid crystal display panel and arranged maintaining a predetermined gap relative to the reflection-type liquid crystal display panel. The display device further includes a source of light arranged on an end surface side of the light guide plate, and a member having a light-diffusing function and interposed between the polarizing element and the light guide plate.
    Type: Grant
    Filed: April 7, 2011
    Date of Patent: March 13, 2012
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tetsuya Hamada, Kunihiro Tashiro, Mari Sugawara, Toshihiro Suzuki, Hidefumi Yoshida
  • Publication number: 20110292097
    Abstract: An illumination device is provided which can reduce a movement blur and a tailing phenomenon on a motion picture display while a drop in display brightness is suppressed, and which can suppress power consumption, can be made small and light, and can prolong the lifetime, and a liquid crystal display device using the same is provided. A light source control part of a control circuit synchronizes a latch pulse signal outputted from a gate driver control part to a gate driver, and outputs light emission control signals to respective light source power supply circuits. The respective light source power supply circuits change emission states of cold cathode fluorescent lamps to one of a first to a third emission states on the basis of the inputted light emission control signals, and illuminate an LCD panel from a rear surface of a display area.
    Type: Application
    Filed: August 5, 2011
    Publication date: December 1, 2011
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Tetsuya Kobayashi, Toshihiro Suzuki, Mari Sugawara, Tetsuya Hamada, Keiji Hayashi, Fumiaki Yamada, Yasutake Furukoshi, Masanori Nishido
  • Patent number: 8049711
    Abstract: A liquid crystal display device including an LCD panel modulating light transmissivities of plural pixels disposed in a matrix form on the basis of respective gradation data; an illumination device for irradiating light to the respective pixels while a ratio (duty ratio) of a lighting time in one frame period is changed; and a display data conversion part for calculating respective lightnesses and a lightness histogram from the respective gradation data, determining a threshold lightness from the lightness histogram on the basis of a previously determined ratio of pixels to be saturated in brightness, processing the respective gradation data on the basis of the threshold lightness to output them to the LCD panel, and outputting duty ratio data to change the duty ratio to the illumination device.
    Type: Grant
    Filed: July 26, 2007
    Date of Patent: November 1, 2011
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tetsuya Kobayashi, Toshihiro Suzuki, Mari Sugawara, Tetsuya Hamada, Keiji Hayashi, Fumiaki Yamada, Yasutake Furukoshi, Masanori Nishido
  • Publication number: 20110181815
    Abstract: To suppress a decrease in the contrast caused by the reflection on the interface to the air layer without decreasing the quality of display. A reflection-type liquid crystal display device includes a light guide plate having a polarizing element stuck or adhered thereto on the side facing a reflection-type liquid crystal display panel and arranged maintaining a predetermined gap relative to the reflection-type liquid crystal display panel. The display device further includes a source of light arranged on an end surface side of the light guide plate, and a member having a light-diffusing function and interposed between the polarizing element and the light guide plate.
    Type: Application
    Filed: April 7, 2011
    Publication date: July 28, 2011
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Tetsuya Hamada, Kunihiro Tashiro, Mari Sugawara, Toshihiro Suzuki, Hidefumi Yoshida
  • Patent number: 7541723
    Abstract: A display device includes a backlight having a discharge tube and a reflector. A heat conduction member is attached to the reflector in contact with the discharge tube, so that a part of the discharge tube is locally cooled by the heat conduction member. Liquid mercury is collected at a first position in the discharge tube, and the backlight is assembled so that the heat conduction member or other cooling device is located at the first position. Also, the display device includes an optical sheet having a diffusion portion having projections containing scattering material particles.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: June 2, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Tetsuya Kobayashi, Tetsuya Hamada, Takeshi Gotoh, Toshihiro Suzuki, Mari Sugawara, Akio Sotokawa, Seiji Hachisuka
  • Patent number: 7494259
    Abstract: A lighting unit including a light-reflecting reflector, a plurality of cold cathode tubes disposed inside the reflector and an optical waveguide connected with an open end of the reflector to guide the light emitted by the cold-cathode tubes. The reflector has a reflective surface that reflects the light having been emitted by the cold-cathode tubes in the direction nearly perpendicular to the wall of each tube, and only in a direction in which the light reflected does not re-enter the cold-cathode tubes. In another embodiment, the lighting unit may include a second optical waveguide disposed in the space between the cold-cathode tube and the reflector, wherein a space is formed between the cold-cathode tube and the second optical waveguide.
    Type: Grant
    Filed: October 1, 2003
    Date of Patent: February 24, 2009
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Takeshi Gotoh, Toshihiro Suzuki, Hisashi Yamaguchi, Tetsuya Kobayashi, Tetsuya Hamada, Mari Sugawara
  • Patent number: 7359011
    Abstract: To suppress a decrease in the contrast caused by the reflection on the interface to the air layer without decreasing the quality of display. A reflection-type liquid crystal display device includes a light guide plate having a polarizing element stuck or adhered thereto on the side facing a reflection-type liquid crystal display panel, a source of light arranged on an end surface side of the light guide plate, and the reflection-type liquid crystal display panel arranged maintaining a predetermined gap relative to the light guide plate, wherein a light-diffusing function is imparted to the surface of the reflection-type liquid crystal display panel on the side facing the light guide plate.
    Type: Grant
    Filed: March 26, 2004
    Date of Patent: April 15, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tetsuya Hamada, Kunihiro Tashiro, Mari Sugawara, Toshihiro Suzuki
  • Publication number: 20080074591
    Abstract: To suppress a decrease in the contrast caused by the reflection on the interface to the air layer without decreasing the quality of display. A reflection-type liquid crystal display device includes a light guide plate having a polarizing element stuck or adhered thereto on the side facing a reflection-type liquid crystal display panel, a source of light arranged on an end surface side of the light guide plate, and the reflection-type liquid crystal display panel arranged maintaining a predetermined gap relative to the light guide plate, wherein a light-diffusing function is imparted to the surface of the reflection-type liquid crystal display panel on the side facing the light guide plate.
    Type: Application
    Filed: November 13, 2007
    Publication date: March 27, 2008
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Tetsuya Hamada, Kunihiro Tashiro, Mari Sugawara, Toshihiro Suzuki, Hidefumi Yoshida
  • Publication number: 20080068331
    Abstract: There is provided a liquid crystal display having good display characteristics and a method of driving the same. Pixel data is written in plural pixels on one gate bus line at a top end of a display area at a first point in time on a line sequential basis. At a second point in time, the writing of pixel data in pixels in an upper part of the screen is completed, and writing of pixel data in pixels in a lower part of the screen is started. At a third point in time, the writing of pixel data in the pixels in the lower part of the screen is completed. A fluorescent tube on the upper side of the screen is turned on for a period between a third point in time after the writing of pixel data in the upper part of the screen and a fourth point in time before writing of pixel data for the next frame is started and is turned off in other periods.
    Type: Application
    Filed: October 30, 2007
    Publication date: March 20, 2008
    Applicants: Sharp Kabushiki Kaisha, Japan Laser Corporation
    Inventors: Mari Sugawara, Tetsuya Kobayashi, Tetsuya Hamada, Takeshi Gotoh, Keiji Hayashi, Toshihiro Suzuki
  • Publication number: 20080062700
    Abstract: A display device includes a backlight having a discharge tube and a reflector. A heat conduction member is attached to the reflector in contact with the discharge tube, so that a part of the discharge tube is locally cooled by the heat conduction member. Liquid mercury is collected at a first position in the discharge tube, and the backlight is assembled so that the heat conduction member or other cooling device is located at the first position. Also, the display device includes an optical sheet having a diffusion portion having projections containing scattering material particles.
    Type: Application
    Filed: October 22, 2007
    Publication date: March 13, 2008
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Tetsuya Kobayashi, Tetsuya Hamada, Takeshi Gotoh, Toshihiro Suzuki, Mari Sugawara, Akio Sotokawa, Seiji Hachisuka
  • Publication number: 20080018575
    Abstract: An illumination device is provided which can reduce a movement blur and a tailing phenomenon on a motion picture display while a drop in display brightness is suppressed, and which can suppress power consumption, can be made small and light, and can prolong the lifetime, and a liquid crystal display device using the same is provided. A light source control part of a control circuit synchronizes a latch pulse signal outputted from a gate driver control part to a gate driver, and outputs light emission control signals to respective light source power supply circuits. The respective light source power supply circuits change emission states of cold cathode fluorescent lamps to one of a first to a third emission states on the basis of the inputted light emission control signals, and illuminate an LCD panel from a rear surface of a display area.
    Type: Application
    Filed: July 26, 2007
    Publication date: January 24, 2008
    Inventors: Tetsuya Kobayashi, Toshihiro Suzuki, Mari Sugawara, Tetsuya Hamada, Keiji Hayashi, Fumiaki Yamada, Yasutake Furukoshi, Masanori Nishido
  • Patent number: 7309146
    Abstract: A display device includes a backlight having a discharge tube and a reflector. A heat conduction member is attached to the reflector in contact with the discharge tube, so that a part of the discharge tube is locally cooled by the heat conduction member. Liquid mercury is collected at a first position in the discharge tube, and the backlight is assembled so that the heat conduction member or other cooling device is located at the first position. Also, the display device includes an optical sheet having a diffusion portion having projections containing scattering material particles.
    Type: Grant
    Filed: April 6, 2005
    Date of Patent: December 18, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Tetsuya Kobayashi, Tetsuya Hamada, Takeshi Gotoh, Toshihiro Suzuki, Mari Sugawara, Akio Sotokawa, Seiji Hachisuka
  • Patent number: 7277079
    Abstract: An illumination device is provided which can reduce a movement blur and a tailing phenomenon on a motion picture display while a drop in display brightness is suppressed, and which can suppress power consumption, can be made small and light, and can prolong the lifetime, and a liquid crystal display device using the same is provided. A light source control part of a control circuit synchronizes a latch pulse signal outputted from a gate driver control part to a gate driver, and outputs light emission control signals to respective light source power supply circuits. The respective light source power supply circuits change emission states of cold cathode fluorescent lamps to one of a first to a third emission states on the basis of the inputted light emission control signals, and illuminate an LCD panel from a rear surface of a display area.
    Type: Grant
    Filed: October 29, 2003
    Date of Patent: October 2, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Tetsuya Kobayashi, Toshihiro Suzuki, Mari Sugawara, Tetsuya Hamada, Keiji Hayashi, Fumiaki Yamada, Yasutake Furukoshi, Masanori Nishido
  • Patent number: 7169005
    Abstract: A display device includes a backlight having a discharge tube and a reflector. A heat conduction member is attached to the reflector in contact with the discharge tube, so that a part of the discharge tube is locally cooled by the heat conduction member. Liquid mercury is collected at a first position in the discharge tube, and the backlight is assembled so that the heat conduction member or other cooling device is located at the first position. Also, the display device includes an optical sheet having a diffusion portion having projections containing scattering material particles.
    Type: Grant
    Filed: June 30, 2005
    Date of Patent: January 30, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Tetsuya Kobayashi, Tetsuya Hamada, Takeshi Gotoh, Toshihiro Suzuki, Mari Sugawara, Akio Sotokawa, Seiji Hachisuka
  • Patent number: 7163331
    Abstract: A lighting unit and a liquid crystal display device which can improve the efficiency of usable light. The lighting unit includes a light source, a light guide plate, and a truncated pyramid located between the light guide plate and the light source. The truncated pyramid has a base, a top smaller than the base, and a slope linking the base and the top. The light source is placed in close contact with the top of the truncated pyramid, and the light guide plate is placed in close contact with the base of the truncated pyramid. Light is propagated from a light emitting part of the light source to the light guide plate without passing through any air layer. Also, an unnecessary light removing structure is provided in the light guide plate near the incidence surface thereof.
    Type: Grant
    Filed: August 15, 2003
    Date of Patent: January 16, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Toshihiro Suzuki, Tetsuya Hamada, Mari Sugawara, Tetsuya Kobayashi, Keiji Hayashi
  • Patent number: 7164224
    Abstract: A display device includes a backlight having a discharge tube and a reflector. A heat conduction member is attached to the reflector in contact with the discharge tube, so that a part of the discharge tube is locally cooled by the heat conduction member. Liquid mercury is collected at a first position in the discharge tube, and the backlight is assembled so that the heat conduction member or other cooling device is located at the first position. Also, the display device includes an optical sheet having a diffusion portion having projections containing scattering material particles.
    Type: Grant
    Filed: December 4, 2001
    Date of Patent: January 16, 2007
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Tetsuya Kobayashi, Tetsuya Hamada, Toshihiro Suzuki, Mari Sugawara
  • Patent number: 7122946
    Abstract: There is provided a light source device, used in a display device and the like, having a high light emitting efficiency. The light source device has an electric discharge tube containing mercury and electrodes at both ends. A heat conducting member is attached to and is in contact with a part of the electric discharge tube. The heat conducting member locally cools the tube. The heat conducting member and the tube satisfy the following relationship, 6×10?5(m2·k)/S<(1/k1?1/k2)W, where a cross sectional area of the electric discharge tube is S (m2), an amount of generate heat per unit length of the electric discharge tubes is W (W/m), heat conductivity of the non-cooling part is k1 (W/K/m), and heat conductivity of the cooling part is defined as k2 (W/K/m).
    Type: Grant
    Filed: August 29, 2003
    Date of Patent: October 17, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Keiji Hayashi, Tetsuya Kobayashi, Toshihiro Suzuki, Tetsuya Hamada, Mari Sugawara
  • Patent number: 7073933
    Abstract: A display device used for a display unit of portable electronic equipment, a light source device therefor and a light guide plate, suppressing dispersion in the brightness and featuring a high contrast and a good display quality. The constitution includes a light incidence surface on where light emitted from an LED falls, a light reflection surface formed facing the light incidence surface and reflects light from the light incidence surface, a light outgoing surface arranged between the light incidence surface and the light reflection surface, and has a circularly polarizing plate intimately adhered onto the surface thereof, and an opposing surface formed facing the light outgoing surface and in which there are alternately arranged first opposing surfaces for guiding the incident light to the light outgoing surface as well as to the light reflection surface, and second opposing surfaces for emitting the light reflected by the light reflection surface through the light outgoing surface.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: July 11, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takeshi Gotoh, Tetsuya Hamada, Toshihiro Suzuki, Tetsuya Kobayashi, Keiji Hayashi, Mari Sugawara
  • Patent number: 7015632
    Abstract: The present invention relates to a light source device including discharge tubes that emit light by discharging in a thin atmosphere, a method of producing the light source device, and a display apparatus in which the light source device is employed. This light source device includes discharge tubes and a heat conductive member that is brought into contact with the neighboring area of the electrodes of the discharge tubes so as to locally cool down the neighboring area of the electrodes. In the light source device, a low heat conductivity member having lower heat conductivity than the heat conductive member is interposed between the heat conductive member and the discharge tubes. With such a structure, the luminance in the entire light source device can be increased and made uniform, and the reliability of the light source device can be increased accordingly.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: March 21, 2006
    Assignees: Sharp Kabushiki Kaisha, Fujitsu Kasei Limited
    Inventors: Tetsuya Kobayashi, Keiji Hayashi, Koshu Yonemura, Fumiaki Yamada, Kazumasa Kaiwa, Hiroyoshi Takahashi, Toshihiro Suzuki, Takeshi Gotoh, Tetsuya Hamada, Mari Sugawara, Seiji Hayashimoto
  • Publication number: 20050276072
    Abstract: The invention relates to a backlight unit for liquid crystal displays, etc.; and its object is to provide a backlight unit not involving the problem that the emitted light leaks out of the optical waveguide, even when the space around the cold-cathode tubes in the light source unit for it is filled with a liquid of which the refractive index is nearly the same as that of the glass material that forms the outer wall of the cold-cathode tubes. The backlight unit comprises a housing 6 which houses cold-cathode tubes 2, 4 therein and of which the inner surface is coated with a light reflector 10; a transparent liquid filled in the housing 6; and an optical waveguide 1 made of a transparent substance and having a light-emitting surface S.
    Type: Application
    Filed: October 1, 2003
    Publication date: December 15, 2005
    Applicant: FUJITSU DISPLAY TECHNOLOGIES CORPORATION
    Inventors: Keiji Hayashi, Takeshi Gotoh, Toshihiro Suzuki, Hisashi Yamaguchi, Tetsuya Kobayashi, Tetsuya Hamada, Mari Sugawara