Patents by Inventor Takashi Ishizumi

Takashi Ishizumi 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: 8791932
    Abstract: A display device includes: an LED control section (4) for carrying out control in which (i) an output luminance of an LED (10) whose measured luminance is deviated from a reference luminance or (ii) output luminances of peripheral LEDs (10) which are provided around the LED (10) is or are corrected, respectively, by using control information of the plurality of LEDs, which control information contains (a) information on measured luminances of the plurality of LEDs, the information being obtained by the plurality of photosensors (11) and (b) positional information of the plurality of LEDs, the positional information being obtained by the plurality of photosensors (11), and a liquid crystal display control section (3) for controlling, based on (i) video signals which have been subjected to the video signal process and are supplied from a video signal processing section (2) and (ii) the control information supplied from the LED control section (4), (a) levels of video signals to be supplied to pixels correspondi
    Type: Grant
    Filed: February 17, 2010
    Date of Patent: July 29, 2014
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Masafumi Ueno, Hiroyuki Furukawa, Kazuyoshi Yoshiyama, Yasuhiro Ohki, Kenji Takase, Takashi Ishizumi
  • Publication number: 20130182200
    Abstract: A light guide plate (11) has: a light incidence surface (11c) through which light from a light source enters the light guide plate; a back surface (11b) for changing a direction of the light which has entered the light guide plate (11) through the light incidence surface (11c); and a light exit surface (11a). The back surface (11b) has a plurality of dot holes (12) each of which has an inclined surface for changing the direction of the light which has entered the light guide plate (11) through the light incidence surface (11a), and an angle ? between the inclined surface of each of the plurality of dot holes 12 and the back surface satisfies 53°???56°.
    Type: Application
    Filed: October 3, 2011
    Publication date: July 18, 2013
    Applicant: SHARP KABUSHIKI KAISHA
    Inventor: Takashi Ishizumi
  • Patent number: 8373640
    Abstract: In one embodiment of the present invention, a display device is disclosed which performs a divided-screen active driving, and which allows (i) its emitting region to be divided into smaller units, irrespective of the smallest module unit of a light source; and (ii) minimizing increase in costs for a driving system and manufacturing of an area light source, a display device of the present invention includes: a display panel having unit display pixels; an area light source arranged on a back surface of the display panel, the area light source having an emitting region which is divided into divided emitting regions; and a controlling section for controlling luminance of each of the divided emitting regions of the area light source, based on luminance information of video signals input, wherein the area light source includes: unit emitting pixels which controls light emission of the divided emitting regions through a matrix driving; the unit emitting pixels each having an electron emitting element for emitting an
    Type: Grant
    Filed: May 19, 2006
    Date of Patent: February 12, 2013
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Ishizumi, Yoshihiro Izumi, Yasukuni Yamane
  • Publication number: 20130027970
    Abstract: An illumination device that can enhance the efficiency of utilization of light is provided. This illumination device includes LEDs (15) that are arranged opposite the light entrance surface (12c) of a light guide plate (12) and an optical path (LP) partitioned by an optically reflective surface (5a) and an optically reflective surface (6a). In at least an optical path region (A) on the side of the light entrance surface (12c) of the entire region of the optical path (LP), the optically reflective surface (5a) and the optically reflective surface (6a) are arranged parallel to each other, and a distance between the optically reflective surface (5a) and the optically reflective surface (6a) in an LED arrangement region (LA) is made greater than a distance between the optically reflective surface (5a) and the optically reflective surface (6a) in the optical path region (A).
    Type: Application
    Filed: January 26, 2011
    Publication date: January 31, 2013
    Inventor: Takashi Ishizumi
  • Publication number: 20120194764
    Abstract: A liquid crystal display device (1) includes: a liquid crystal display panel (10) for displaying an image; and a blue LED (32) for emitting light to the liquid crystal display panel (10). The liquid crystal display panel (10) includes a glass substrate (12) provided on the side on which the blue LED (32) is provided and a glass substrate (19) facing the glass substrate (12) via a liquid crystal layer (17). On the glass substrate (12), a fluorescent layer (13) configured to emit light of a plurality of different colors for displaying the image is provided so as to lie between the glass substrate (12) and the liquid crystal layer (17). The blue LED (32) is configured to emit blue light for exciting the fluorescent layer (13). This improves the use efficiency of light from a light source, and prevents a reduction in reliability and an increase in cost.
    Type: Application
    Filed: June 28, 2010
    Publication date: August 2, 2012
    Applicant: Sharp Kabushiki Kaisha
    Inventor: Takashi Ishizumi
  • Publication number: 20120113164
    Abstract: A liquid crystal data calculation section forms, on the basis of input image data, liquid crystal data to display an image on a liquid crystal panel. In at least one example embodiment, an LED data calculation section forms, on the basis of the input image data, LED data for adjusting an amount of light of an LED backlight. An LED control section controls an amount of an output current of an LED power source on the basis of the LED data, and includes a protection function of limiting the amount of the output current so that the amount of the output current does not exceed a predetermined upper limit. In a case where the amount of the output current of the LED power source is reduced to the upper limit by the LED control section, a liquid crystal transmittance correction section corrects the liquid crystal data and increases transmittance so as to compensate reduction in luminance of the backlight.
    Type: Application
    Filed: March 31, 2010
    Publication date: May 10, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Hiroyuki Furukawa, Kazuyoshi Yoshiyama, Yasuhiro Ohki, Masafumi Ueno, Takashi Ishizumi, Kenji Takase
  • Publication number: 20120075274
    Abstract: A display device includes: an LED control section (4) for carrying out control in which (i) an output luminance of an LED (10) whose measured luminance is deviated from a reference luminance or (ii) output luminances of peripheral LEDs (10) which are provided around the LED (10) is or are corrected, respectively, by using control information of the plurality of LEDs, which control information contains (a) information on measured luminances of the plurality of LEDs, the information being obtained by the plurality of photosensors (11) and (b) positional information of the plurality of LEDs, the positional information being obtained by the plurality of photosensors (11), and a liquid crystal display control section (3) for controlling, based on (i) video signals which have been subjected to the video signal process and are supplied from a video signal processing section (2) and (ii) the control information supplied from the LED control section (4), (a) levels of video signals to be supplied to pixels correspondi
    Type: Application
    Filed: February 17, 2010
    Publication date: March 29, 2012
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Masafumi Ueno, Hiroyuki Furukawa, Kazuyoshi Yoshiyama, Yasuhiro Ohki, Kenji Takase, Takashi Ishizumi
  • Patent number: 8130340
    Abstract: A large liquid crystal display (100) comprises a light guide plate (3) arranged on the back side of a liquid crystal panel (1). The front surface of the light guide plate (3) is flat, while the back surface thereof is concave. The upper and lower end faces of the light guide plate (3) respectively facing hot cathode fluorescent lamps (2a, 2b) have a convex shape projecting toward the respective lamps. White light from the fluorescent lamps is incident on the upper and lower end faces of the light guide plate directly or by being reflected by reflectors (4a, 4b), and propagates within the light guide plate while being reflected by the front and back surfaces of the light guide plate. At the front surface of the light guide plate, a part of the white light is directed toward the back side of the liquid crystal panel (1) by a light guide portion (5).
    Type: Grant
    Filed: August 14, 2006
    Date of Patent: March 6, 2012
    Assignees: Tohoku University, Kuraray Co., Ltd., Sharp Corporation
    Inventors: Tadahiro Ohmi, Yasuyuki Shirai, Kiwamu Takehisa, Mitsuo Matsumoto, Tokuo Ikari, Toshiaki Sato, Ikuo Onishi, Etsuo Nakazato, Yuichiro Yamada, Tokihiko Shinomiya, Takashi Ishizumi, Yuhsaku Ajichi
  • Publication number: 20090103009
    Abstract: A large liquid crystal display (100) comprises a light guide plate (3) arranged on the back side of a liquid crystal panel (1). The front surface of the light guide plate (3) is flat, while the back surface thereof is concave. The upper and lower end faces of the light guide plate (3) respectively facing hot cathode fluorescent lamps (2a, 2b) have a convex shape projecting toward the respective lamps. White light from the fluorescent lamps is incident on the upper and lower end faces of the light guide plate directly or by being reflected by reflectors (4a, 4b), and propagates within the light guide plate while being reflected by the front and back surfaces of the light guide plate. At the front surface of the light guide plate, a part of the white light is directed toward the back side of the liquid crystal panel (1) by a light guide portion (5).
    Type: Application
    Filed: August 14, 2006
    Publication date: April 23, 2009
    Inventors: Tadahiro Ohmi, Yasuyuki Shirai, Kiwamu Takehisa, Mitsuo Matsumoto, Tokuo Ikari, Toshiaki Sato, Ikuo Onishi, Etsuo Nakazato, Yuichiro Yamada, Tokihiko Shinomiya, Takashi Ishizumi, Yuhsaku Ajichi
  • Publication number: 20090040171
    Abstract: In one embodiment of the present invention, a display device is disclosed which performs a divided-screen active driving, and which allows (i) its emitting region to be divided into smaller units, irrespective of the smallest module unit of a light source; and (ii) minimizing increase in costs for a driving system and manufacturing of an area light source, a display device of the present invention includes: a display panel having unit display pixels; an area light source arranged on a back surface of the display panel, the area light source having an emitting region which is divided into divided emitting regions; and a controlling section for controlling luminance of each of the divided emitting regions of the area light source, based on luminance information of video signals input, wherein the area light source includes: unit emitting pixels which controls light emission of the divided emitting regions through a matrix driving; the unit emitting pixels each having an electron emitting element for emitting an
    Type: Application
    Filed: May 19, 2006
    Publication date: February 12, 2009
    Inventors: Takashi Ishizumi, Yoshihiro Izumi, Yasukuni Yamane
  • Patent number: 7382426
    Abstract: A liquid crystal display unit is characterized by comprising a liquid crystal display panel, a back-light instrument for outputting light to the liquid crystal display panel, and a scattering-anisotropic optical instrument disposed on that side of the liquid crystal display panel which is opposite to the back-light instrument. The scattering-anisotropic optical instrument is so formed that the scattering intensity of light vertically entering the display screen of the liquid crystal panel is maximized. Therefore, the scattering-anisotropic optical instrument can scatter light vertically entering the display screen of the liquid crystal panel to allow a viewer to view a display screen from a wide range of viewing angles. In addition, because the unit does not scatter light entering obliquely, rather than vertically, a display screen but lets the light pass as it is, whitish appearance as is seen in an oblique-direction observation can be prevented.
    Type: Grant
    Filed: April 21, 2004
    Date of Patent: June 3, 2008
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Ishizumi, Motohiro Yamahara
  • Publication number: 20060170841
    Abstract: A liquid crystal display unit is characterized by comprising a liquid crystal display panel, a back-light instrument for outputting light to the liquid crystal display panel, and a scattering-anisotropic optical instrument disposed on that side of the liquid crystal display panel which is opposite to the back-light instrument. The scattering-anisotropic optical instrument is so formed that the scattering intensity of light vertically entering the display screen of the liquid crystal panel is maximized. Therefore, the scattering-anisotropic optical instrument can scatter light vertically entering the display screen of the liquid crystal panel to allow a viewer to view a display screen from a wide range of viewing angles. In addition, because the unit does not scatter light entering obliquely, rather than vertically, a display screen but lets the light pass as it is, whitish appearance as is seen in an oblique-direction observation can be prevented.
    Type: Application
    Filed: April 21, 2004
    Publication date: August 3, 2006
    Inventors: Takashi Ishizumi, Motohiro Yamahara
  • Patent number: 6009113
    Abstract: A semiconductor laser device having high performance, low operating voltage, and long service life, and a method for fabricating the same are provided. A semiconductor multilayer film including an active layer for use of laser beam oscillation is stacked on a substrate. Then a clad layer composed of p-type AlGaAs doped with a p-type impurity Mg, and a contact layer composed of p-type GaAs doped also with Mg are grown by an LPE growth process, and further a surface layer having a high-resistance portion present in the contact layer and low in carrier concentration is removed. The active layer for use of laser beam oscillation is arranged in a substantially center of an end surface from which the laser beam is emitted.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: December 28, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Taiji Morimoto, Zenkichi Shibata, Takashi Ishizumi, Keisuke Miyazaki, Toshio Hata, Yoshinori Ohitsu
  • Patent number: 6001665
    Abstract: The present invention provides a method for producing a semiconductor laser device having at least a light emitting section, a cap layer and an electrode successively formed on a semiconductor substrate, the light emitting section including a light emitting layer located approximately in a middle of a thickness of the device. The method includes the step of growing the light emitting section and the cap layer using a vapor phase epitaxy method, wherein a growth rate of the cap layer is greater than a growth rate of the light emitting section.
    Type: Grant
    Filed: March 9, 1998
    Date of Patent: December 14, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Ishizumi, Shinji Kaneiwa
  • Patent number: 5932004
    Abstract: A semiconductor laser device having high performance, low operating voltage, and long service life, and a method for fabricating the same are provided. A semiconductor multilayer film including an active layer for use of laser beam oscillation is stacked on a substrate. Then a clad layer composed of p-type AlGaAs doped with a p-type impurity Mg, and a contact layer composed of p-type GaAs doped also with Mg are grown by an LPE growth process, and further a surface layer having a high-resistance portion present in the contact layer and low in carrier concentration is removed. The active layer for use of laser beam oscillation is arranged in a substantially center of an end surface from which the laser beam is emitted.
    Type: Grant
    Filed: May 22, 1997
    Date of Patent: August 3, 1999
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Taiji Morimoto, Zenkichi Shibata, Takashi Ishizumi, Keisuke Miyazaki, Toshio Hata, Yoshinori Ohitsu
  • Patent number: 5730802
    Abstract: A vapor growth apparatus and a vapor growth method is capable of growing a compound semiconductor layer having an evenness and an interfacial sharpness in units of atomic layers with a good productivity. A growth chamber has a cylindrical portion and an end plate which closes an upstream end of the cylindrical portion. The end plate is provided with a cation gas material supply inlet and an anion material gas supply inlet, while an exhaust device is provided on the downstream side of the cylindrical portion. A substrate holder having a substrate support surface is provided in the cylinder portion. A gas separating member separates flow paths of material gases from each other, thereby forming on the substrate support surface a plurality of material gas supply areas to which the material gases are independently supplied. A drive device rotates the substrate holder with a substrate set on the substrate support surface thereof around the center line of the cylindrical portion.
    Type: Grant
    Filed: December 27, 1996
    Date of Patent: March 24, 1998
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takashi Ishizumi, Shinji Kaneiwa