Patents by Inventor Hisashi Yamaguchi

Hisashi Yamaguchi 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: 6661488
    Abstract: A vertically alignment mode liquid crystal display device having an improved viewing angle characteristic is disclosed. The disclosed liquid crystal display device uses a liquid crystal having a negative anisotropic dielectric constant, and orientations of the liquid crystal are vertical to substrates when no voltage being applied, almost horizontal when a predetermined voltage is applied, and oblique when an intermediate voltage is applied. At least one of the substrates includes a structure as domain regulating means, and inclined surfaces of the structure operate as a trigger to regulate azimuths of the oblique orientations of the liquid crystal when the intermediate voltage is applied.
    Type: Grant
    Filed: September 18, 2000
    Date of Patent: December 9, 2003
    Assignee: Fujitsu Limited
    Inventors: Arihiro Takeda, Katsufumi Ohmuro, Yoshio Koike, Shingo Kataoka, Takahiro Sasaki, Takashi Sasabayashi, Hideaki Tsuda, Hideo Chida, Makoto Ohashi, Kenji Okamoto, Hisashi Yamaguchi, Minoru Otani, Makoto Morishige, Noriaki Furukawa, Tsuyoshi Kamada, Yoshinori Tanaka, Atuyuki Hoshino, Shougo Hayashi, Hideaki Takizawa, Takeshi Kinjou, Makoto Tachibanaki, Keiji Imoto, Tadashi Hasegawa, Hidefumi Yoshida, Hiroyasu Inoue, Yoji Taniguchi, Tetsuya Fujikawa, Satoshi Murata, Manabu Sawasaki, Tomonori Tanose, Siro Hirota, Masahiro Ikeda, Kunihiro Tashiro, Kouji Tsukao, Yasutoshi Tasaka, Takatoshi Mayama, Seiji Tanuma, Yohei Nakanishi
  • Patent number: 6655810
    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: Grant
    Filed: March 30, 2001
    Date of Patent: December 2, 2003
    Assignee: Fujitsu Display Technologies Corporation
    Inventors: Keiji Hayashi, Takeshi Gotoh, Toshihiro Suzuki, Hisashi Yamaguchi, Tetsuya Kobayashi, Tetsuya Hamada, Mari Sugawara
  • Patent number: 6639642
    Abstract: A display device including a diffraction grating from which a diffracted light of the zeroth order and a diffracted light of the first order having different color light components emerge to establish color separation. An array of micro-lenses is arranged on a liquid crystal panel. The liquid crystal panel has a plurality of picture elements and each picture element includes a plurality of color display dots. The color display dots in each picture element are arranged in the vertical relationship and in the order of wavelength of the light. A green light component of diffracted light of the first order is made incident normal to the liquid crystal panel, and the diffracted light of the zeroth order passes through the liquid crystal panel at a greater angle relative to the normal to the liquid crystal panel.
    Type: Grant
    Filed: March 10, 2000
    Date of Patent: October 28, 2003
    Assignee: Fujitsu Limited
    Inventors: Toshihiro Suzuki, Yukio Iigahama, Hisashi Yamaguchi, Takeshi Gotoh, Tetsuya Hamada, Keiji Hayashi, Junji Tomita, Hirokazu Aritake, Tetsuya Kobayashi, Mari Sugawara, Motohiko Fukuhara, Koji Yoshioka, Kazuhiro Takahara
  • Publication number: 20030132899
    Abstract: A display device for realizing gray-scale display by changing an amplitude of a modulation voltage which is output from a data-side driving circuit. A driving control circuit is capable of supplying a first display data signal representing (m+n) grades, obtained by adding m grades represented by a second display data signal externally input and an adjustable range n. The data-side driving circuit is capable of outputting modulation voltages having (m+n) types of amplitudes to a plurality of first electrodes in accordance with a first display data signal. The amplitude of the modulation voltage corresponding to the light emission characteristic of a prescribed light emitting layer among a plurality of light emitting layers is adjusted to an amplitude in the adjustable range n from the amplitude corresponding to the grade represented by the second display data signal.
    Type: Application
    Filed: September 26, 2002
    Publication date: July 17, 2003
    Inventors: Hisashi Yamaguchi, Kyouichi Yamamoto
  • Publication number: 20030098933
    Abstract: The display device includes a spatial modulator having a plurality of pixels and a periodical structural body having condenser elements corresponding to the pixels of the spatial modulator. Each of the pixels of the spatial modulator includes a plurality of color dots arranged in a first direction. A length of a peripheral region of the respective pixel encircling the plurality of color dots, measured in the first direction, is longer than a length of the condenser element of the periodical structural body, measured in the first direction. In addition, combinations of the pixels in the square, delta or mosaic arrangement with the condenser elements in the square, delta or mosaic arrangement are disclosed.
    Type: Application
    Filed: January 14, 2003
    Publication date: May 29, 2003
    Applicant: Fujitsu Limited
    Inventors: Toshihiro Suzuki, Tetsuya Kobayashi, Takeshi Gotoh, Tetsuya Hamada, Keiji Hayashi, Mari Sugawara, Hisashi Yamaguchi, Junji Tomita, Hirokazu Aritake
  • Patent number: 6559910
    Abstract: The display device includes a spatial modulator having a plurality of pixels and a periodical structural body having condenser elements corresponding to the pixels of the spatial modulator. Each of the pixels of the spatial modulator includes a plurality of color dots arranged in a first direction. A length of a peripheral region of the respective pixel encircling the plurality of color dots, measured in the first direction, is longer than a length of the condenser element of the periodical structural body, measured in the first direction. In addition, combinations of the pixels in the square, delta or mosaic arrangement with the condenser elements in the square, delta or mosaic arrangement are disclosed.
    Type: Grant
    Filed: January 5, 1999
    Date of Patent: May 6, 2003
    Assignee: Fujitsu Limited
    Inventors: Toshihiro Suzuki, Tetsuya Kobayashi, Takeshi Gotoh, Tetsuya Hamada, Keiji Hayashi, Mari Sugawara, Hisashi Yamaguchi, Junji Tomita, Hirokazu Aritake
  • Patent number: 6552760
    Abstract: A lens array 22C has convex lenses 221 and 221C arranged in alternate and staggering manner to one another. In combination with a condenser lens 23, the convex lenses 221 form images of respective convex lenses 211 of a lens array 21 on a plane 24 to be illuminated in overlapping so that an illuminance distribution on the plane 24 is almost uniform, while the convex lenses 221C whose focal length is longer than that of the convex lenses 211 make on the plane 24 an illuminance distribution of a mountain-shape. Flat plate portions and concave lenses may be employed instead of the convex lenses 221C. A polarization conversion element comprises two elements and an element disposed therebetween with its longitudinal direction being perpendicular to the two element. The images of a light emitting part are included in band-shaped useful incident areas.
    Type: Grant
    Filed: February 17, 2000
    Date of Patent: April 22, 2003
    Assignee: Fujitsu Limited
    Inventors: Takeshi Gotoh, Toshihiro Suzuki, Tetsuya Kobayashi, Tetsuya Hamada, Mari Sugawara, Keiji Hayashi, Noriyuki Ohashi, Hisashi Yamaguchi
  • Patent number: 6552709
    Abstract: In a display driving method, after turning a power supply ON, a shift clock CKI2 of a period of 1 &mgr;s is supplied to a shift register in a scanning electrode driving circuit as a shift clock CK2 instead of a shift clock CKN2 of one horizontal synchronous period for n-periods corresponding to n-pieces of scanning electrodes of a liquid crystal, and by an enable signal EN which becomes a “H” level during a period corresponding to n-periods at least, each bit of output data of a shift driver is stopped from transferring to n-pieces of drivers for driving n-pieces of scanning electrodes of a liquid crystal display panel.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: April 22, 2003
    Assignee: NEC Corporation
    Inventor: Hisashi Yamaguchi
  • Publication number: 20030001810
    Abstract: A method is provided for driving a liquid crystal display capable of preventing degradation of linearity of a gamma characteristic, of achieving display of a high quality image in a simple and low-priced configuration and of solving problems associated with environmental changes, frequency characteristic of timing signals, change in a gamma characteristic caused by luminance of a backlight, or dispersion in a gamma characteristic occurring during processes of manufacturing a color liquid crystal display. The method includes acquirement of first corrected red data, first corrected green data, and first corrected blue data each being of 10 bits to which information to change a gray scale two or more times for every red data, green data, and blue data has been added when a gamma correction is made to red, green, and blue data each being of 8 bits and generation of data red, green, and blue signals to be fed to a data electrode of a liquid crystal display to perform frame rate control.
    Type: Application
    Filed: July 1, 2002
    Publication date: January 2, 2003
    Inventors: Hisashi Yamaguchi, Takashi Yazaki
  • Patent number: 6481854
    Abstract: The projection type display apparatus has liquid crystal panels with polarizers, a light source, a power supply, and a ballast. A cooling device is arranged in the apparatus such that a first set of cooling fans blow cooling air to cool the liquid crystal panels and the polarizers, and a second set of cooling fans suck the cooling air passing through the liquid crystal panels and the polarizers and blow the cooling air to independently cool the light source, the power supply, and the ballast. Therefore, a projection type display apparatus with little light leakage and low noise can be realized. The invention also provides a cooling unit, for the light source, which includes a movable lamp house and a duct with a cooling fan.
    Type: Grant
    Filed: December 1, 1999
    Date of Patent: November 19, 2002
    Assignee: Fujitsu Limited
    Inventors: Mari Sugawara, Tetsuya Hamada, Tetsuya Kobayashi, Toshihiro Suzuki, Takeshi Gotoh, Keiji Hayashi, Hisashi Yamaguchi, Noriyuki Ohashi
  • Patent number: 6476591
    Abstract: A power supply device for driving liquid crystal which generates four liquid crystal drive voltages V1 and V4 between first and second reference voltages, the power supply device comprising: a voltage division circuit 102 which divides a voltage between voltages between voltages V1 and V5 and generates four pairs of first voltages NV1 to NV4 and second voltages PV1 to PV4; and four impedance conversion circuits 103 and 104 which generate impedance converted liquid crystal drive voltages V1 to V4 based on the four pairs of the first and second voltages. Each impedance conversion circuit comprises voltage follower type of differential amplifier circuits 120 and 110 to which a pair of the first and second voltages is input, and an output circuit 130 which is driven by the differential amplification circuits. The N-type transistor 134 and P-type transistor 132 in the output circuit are independently driven by the first and second output voltages VN, VP from the differential amplification circuits 120 and 110.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: November 5, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Hisashi Yamaguchi, Tadashi Yasue
  • Patent number: 6392726
    Abstract: A screen has a screen main body, a power supply and a voltage regulator. The screen main body has a Fresnel lens, a polymer dispersed liquid crystal unit and a lenticular lens. The liquid crystal unit includes a polymer dispersed liquid crystal and a pair of transparent electrodes which sandwich the polymer dispersed liquid crystal. By operating the voltage regulator, a voltage applied to the electrodes is adjusted so that a gain of the liquid crystal is controlled.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: May 21, 2002
    Assignee: Fujitsu Limited
    Inventors: Takeshi Goto, Toshihiro Suzuki, Tetsuya Kobayashi, Hisashi Yamaguchi
  • Patent number: 6379010
    Abstract: The present invention relates to a projection type display using a transmission type liquid crystal light valve, and its object is to supply a projection type display capable of exhibiting a high quality gradation display by preventing a leak current at a switching device. The projection type display comprises three liquid crystal light valves 21R, 21G, and 21B which have polarizing plates 20Rp, 20Gp, and 20Bp, modulate in intensity and emit each light of color components of red, green, and blue, and a dichroic prism to synthesize exiting lights from respective light valves. The projection type display is structured to arrange half-wave plates 20Ri, and 20Gi between the liquid crystal light valves 21R, and 21G for red and green, to set a polarizing direction of an exiting light of a blue component orthogonal to polarizing directions of the other two exiting lights.
    Type: Grant
    Filed: March 29, 1999
    Date of Patent: April 30, 2002
    Assignee: Fujitsu Limited
    Inventors: Toshihiro Suzuki, Tetsuya Kobayashi, Tetsuya Hamada, Takeshi Gotoh, Mari Sugawara, Keiji Hayashi, Hisashi Yamaguchi
  • Publication number: 20020018151
    Abstract: The display device includes a spatial modulator having a plurality of pixels and a periodical structural body having condenser elements corresponding to the pixels of the spatial modulator. Each of the pixels of the spatial modulator includes a plurality of color dots arranged in a first direction. A length of a peripheral region of the respective pixel encircling the plurality of color dots, measured in the first direction, is longer than a length of the condenser element of the periodical structural body, measured in the first direction. In addition, combinations of the pixels in the square, delta or mosaic arrangement with the condenser elements in the square, delta or mosaic arrangement are disclosed.
    Type: Application
    Filed: January 5, 1999
    Publication date: February 14, 2002
    Applicant: Fujitsu Limited
    Inventors: TOSHIHIRO SUZUKI, TETSUYA KOBAYASHI, TAKESHI GOTOH, TETSUYA HAMADA, KEIJI HAYASHI, MARI SUGAWARA, HISASHI YAMAGUCHI, JUNJI TOMITA, HIROKAZU ARITAKE
  • Publication number: 20020017932
    Abstract: A power supply device for driving liquid crystal which generates four liquid crystal drive voltages V1 and V4 between first and second reference voltages, the power supply device comprising: a voltage division circuit 102 which divides a voltage between voltages between voltages V1 and V5 and generates four pairs of first voltages NV1 to NV4 and second voltages PV1 to PV4; and four impedance conversion circuits 103 and 104 which generate impedance converted liquid crystal drive voltages V1 to V4 based on the four pairs of the first and second voltages. Each impedance conversion circuit comprises voltage follower type of differential amplifier circuits 120 and 110 to which a pair of the first and second voltages is input, and an output circuit 130 which is driven by the differential amplification circuits. The N-type transistor 134 and P-type transistor 132 in the output circuit are independently driven by the first and second output voltages VN, VP from the differential amplification circuits 120 and 110.
    Type: Application
    Filed: October 17, 2001
    Publication date: February 14, 2002
    Applicant: Seiko Epson Corporation
    Inventors: Hisashi Yamaguchi, Tadashi Yasue
  • Publication number: 20020015297
    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: March 30, 2001
    Publication date: February 7, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Keiji Hayashi, Takeshi Gotoh, Toshihiro Suzuki, Hisashi Yamaguchi, Tetsuya Kobayashi, Tetsuya Hamada, Mari Sugawara
  • Publication number: 20020012082
    Abstract: A screen has a screen main body, a power supply and a voltage regulator. The screen main body has a Flesnel lens, a polymer dispersed liquid crystal unit and a lenticular lens 15. The liquid crystal unit includes a polymer dispersed liquid crystal and a pair of transparent electrodes which sandwich the polymer dispersed liquid crystal. By operating the voltage regulator, a voltage applied to the electrodes is adjusted so that a gain of the liquid crystal is controlled.
    Type: Application
    Filed: October 1, 1997
    Publication date: January 31, 2002
    Inventors: TAKESHI GOTO, TOSHIHIRO SUZUKI, TETSUYA KOBAYASHI, HISASHI YAMAGUCHI
  • Patent number: 6342782
    Abstract: A power supply device for driving liquid crystal which generates four liquid crystal drive voltages V1 and V4 between first and second reference voltages, the power supply device comprising: a voltage division circuit 102 which divides a voltage between voltages between voltages V1 and V5 and generates four pairs of first voltages NV1 to NV4 and second voltages PV1 to PV4; and four impedance conversion circuits 103 and 104 which generate impedance converted liquid crystal drive voltages V1 to V4 based on the four pairs of the first and second voltages. Each impedance conversion circuit comprises voltage follower type of differential amplifier circuits 120 and 110 to which a pair of the first and second voltages is input, and an output circuit 130 which is driven by the differential amplification circuits. The N-type transistor 134 and P-type transistor 132 in the output circuit are independently driven by the first and second output voltages VN, VP from the differential amplification circuits 120 and 110.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: January 29, 2002
    Assignee: Seiko Epson Corporation
    Inventors: Hisashi Yamaguchi, Tadashi Yasue
  • Patent number: 6329975
    Abstract: A liquid crystal display device comprising a start pulse generation circuit which gives the timing for displaying a received image in a fixed position on a liquid crystal display panel, another start pulse generating circuit which gives the timing for displaying the received image in a specified position on the liquid crystal display panel in response to enable signal indicating an effective display data period concerning the received image from the outside, and selectors which select one of these circuits in response to a select signal. The liquid crystal display device according to this present invention has a data enable signal detection circuit which detects the data enable signal and outputs the result to the selectors as the select signal.
    Type: Grant
    Filed: March 13, 1997
    Date of Patent: December 11, 2001
    Assignee: NEC Corporation
    Inventor: Hisashi Yamaguchi
  • Publication number: 20010048417
    Abstract: A liquid crystal display device comprising a start pulse generation circuit which gives the timing for displaying a received image in a fixed position on a liquid crystal display panel, another start pulse generating circuit which gives the timing for displaying the received image in a specified position on the liquid crystal display panel in response to enable signal indicating an effective display data period concerning the received image from the outside, and selectors which select one of these circuits in response to a select signal. The liquid crystal display device according to this present invention has a data enable signal detection circuit which detects the data enable signal and outputs the result to the selectors as the select signal.
    Type: Application
    Filed: July 31, 2001
    Publication date: December 6, 2001
    Inventor: Hisashi Yamaguchi