Patents by Inventor Yasutoshi Tasaka

Yasutoshi Tasaka 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: 20040119924
    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: Application
    Filed: November 21, 2003
    Publication date: June 24, 2004
    Applicant: Fujitsu Display Technology Corporation
    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: 6724452
    Abstract: A vertical alignment mode liquid crystal display device having an improved viewing angle characteristic is provided. The 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 is 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: June 12, 1998
    Date of Patent: April 20, 2004
    Assignee: Fujitsu Display Technologies Corporation
    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
  • Publication number: 20040066480
    Abstract: A liquid crystal is arranged between a pair of substrates. One substrate has a plurality of stripe electrodes extending parallel to each other, and the other substrate has a transparent electrode covering substantially the whole surface of the other substrate. An oblique electric field is formed between the stripe electrodes and the transparent electrode, so that the liquid crystal molecules are aligned along the oblique electric field. In addition, a dielectric layer is arranged between the transparent electrode and the alignment layer.
    Type: Application
    Filed: September 3, 2003
    Publication date: April 8, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Yohei Nakanishi, Kimiaki Nakamura, Yoshio Koike, Tetsuya Fujikawa
  • Publication number: 20040046915
    Abstract: In a vertically aligned liquid crystal display device for controlling liquid crystal molecules alignment in voltage application by providing linear structures or linear slits consisting of a plurality of constituent units to at least one of a pair of substrates having an electrode thereon, there is provided alignment controlling means for forming an alignment singular point s=−1 of liquid crystal molecules at an intersecting point between the structures on the pixel electrode or the slits in the electrode and an edge of a pixel electrode on one of the substrates.
    Type: Application
    Filed: September 8, 2003
    Publication date: March 11, 2004
    Applicant: FUJITSU DISPLAY TECHNOLOGIES CORPORATION
    Inventors: Arihiro Takeda, Yoshio Koike, Takahiro Sasaki, Kouji Tsukao, Shingo Kataoka, Kimiaki Nakamura, Yuichi Inoue, Kazutaka Hanaoka, Seiji Tanuma, Takatoshi Mayama, Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Yohei Nakanishi
  • 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: 6642984
    Abstract: A liquid crystal is arranged between a pair of substrates. One substrate has a plurality of stripe electrodes extending parallel to each other, and the other substrate has a transparent electrode covering substantially the whole surface of the other substrate. An oblique electric field is formed between the stripe electrodes and the transparent electrode, so that the liquid crystal molecules are aligned along the oblique electric field. In addition, a dielectric layer is arranged between the transparent electrode and the alignment layer.
    Type: Grant
    Filed: December 7, 1999
    Date of Patent: November 4, 2003
    Assignee: Fujitsu Display Technologies Corporation
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Yohei Nakanishi, Takatoshi Mayama
  • Publication number: 20030202146
    Abstract: In a vertically aligned liquid crystal display device for controlling liquid crystal molecules alignment in voltage application by providing linear structures or linear slits consisting of a plurality of constituent units to at least one of a pair of substrates having an electrode thereon, there is provided alignment controlling means for forming an alignment singular point s=−1 of liquid crystal molecules at an intersecting point between the structures on the pixel electrode or the slits in the electrode and an edge of a pixel electrode on one of the substrates.
    Type: Application
    Filed: April 25, 2003
    Publication date: October 30, 2003
    Applicants: Fujitsu Limited, Fujitsu Display Technologies Corporation
    Inventors: Arihiro Takeda, Yoshio Koike, Takahiro Sasaki, Kouji Tsukao, Shingo Kataoka, Kimiaki Nakamura, Yuichi Inoue, Kazutaka Hanaoka, Seiji Tanuma, Takatoshi Mayama, Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Yohei Nakanishi
  • Publication number: 20030202143
    Abstract: A liquid crystal display device including a pair of substrates in a spaced relationship with one another. A pair of alignment films are provided, one alignment film being formed on each substrate such that the alignment films face one another. A liquid crystal layer, including plural liquid crystals, is inserted between the pair of alignment films, wherein the alignment films impart a given pre-tilt angle to the liquid crystals. The alignment films are composed of a material containing at least two types of polymers having a prescribed initial alignment and different alignment variation rates in response to ultra-violet ray irradiation. The pre-tilt angle being adjusted, without rubbing the alignment films, through ultraviolet exposure of the alignment films.
    Type: Application
    Filed: April 24, 2003
    Publication date: October 30, 2003
    Applicant: Fujitsu Display Technologies Corporation
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Yohei Nakanishi, Kenji Okamoto
  • Publication number: 20030193625
    Abstract: The invention relates to a substrate for a liquid crystal display used in a display section of an information apparatus and a liquid crystal display having the same and provides a substrate for a liquid crystal display and a liquid crystal display having the same that provide good display characteristics without any increase in manufacturing steps. A configuration is employed which includes a plurality of gate bus lines formed on a substrate substantially in parallel with each other, a plurality of drain bus lines formed on the substrate such that they intersect the gate bus lines with an insulation film interposed therebetween, pixel regions provided on the substrate in the form of a matrix, pixel electrodes having a plurality of electrode units formed in the pixel regions, slits formed between the electrode units, and connection electrodes for connecting the plurality of electrode units with each other and a thin film transistor formed at each pixel region.
    Type: Application
    Filed: April 7, 2003
    Publication date: October 16, 2003
    Applicant: FUJITSU DISPLAY TECHNOLOGIES CORP.
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Takahiro Sasaki, Arihiro Takeda, Kazuya Ueda
  • Patent number: 6583835
    Abstract: A liquid crystal display device including a pair of substrates in a spaced relationship with one another. A pair of alignment films are provided, one alignment film being formed on each substrate such that the alignment films face one another. A liquid crystal layer, including plural liquid crystals, is inserted between the pair of alignment films, wherein the alignment films impart a given pre-tilt angle to the liquid crystals. The alignment films are composed of a material containing at least two types of polymers having a prescribed initial alignment and different alignment variation rates in response to ultra-violet ray irradiation. The pre-tilt angle being adjusted, without rubbing the alignment films, through ultraviolet exposure of the alignment films.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: June 24, 2003
    Assignee: Fujitsu Display Technologies Corporation
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Yohei Nakanishi, Kenji Okamoto
  • Publication number: 20030112394
    Abstract: The liquid crystal display device comprising a pair of substrates with alignment layers formed thereon, and a liquid crystal filled between the substrates. Each pixel has pixel display portions CA, CB and non-display portions DA, EA, DB, EB. The pixel display portions are treated for realizing alignment in a different manner from the non-display portions and the alignment of the pixel display portions is controlled by the alignment of the non-display portions. Moreover, the alignment treatment is executed by the irradiation with ultraviolet rays in an inclined direction.
    Type: Application
    Filed: December 12, 2002
    Publication date: June 19, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Hidefumi Yoshida, Tsutomu Seino, Yasutoshi Tasaka
  • Publication number: 20030071952
    Abstract: A liquid crystal display device is provided which has a pair of substrates and a liquid crystal layer sandwiched between the pair of substrates, in which liquid crystal molecules are vertically aligned with respect to the substrates when no voltage is applied between the substrates and the liquid crystal molecules tilt in a plurality of directions to be almost parallel to the substrates by applying a voltage between the substrates. In the liquid crystal layer, when the voltage is applied, a proportion of a region where the liquid crystal molecules tilt in a direction of 0 degrees to 180 degrees is different from a proportion of a region where the liquid crystal molecules tilt in a direction of 180 degrees to 360 degrees with the angle being defined counterclockwise with the right direction on a screen being 0 degrees.
    Type: Application
    Filed: March 28, 2002
    Publication date: April 17, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Hidefumi Yoshida, Takashi Sasabayashi, Arihiro Takeda, Yasutoshi Tasaka, Hideo Chida, Yoshio Koike
  • Patent number: 6535260
    Abstract: A method of fabricating a liquid crystal display device including vertical alignment layers formed on the substrates. The alignment layer having a polymer realizing vertical alignment is formed on the substrate an unpolarized ultraviolet light is then irradiated in the oblique direction at an angle not more than 45 degrees with respect to the surface of the alignment layer. The ultraviolet light has an exposure energy of 30 to 120 mJ/cm2 per percent of the polymer content realizing the vertical alignment of the alignment layer. The liquid crystal can thus align substantially vertically to the surface of the alignment layer, with a pretilt, and such an alignment is realized by the irradiation of the ultraviolet light, without rubbing.
    Type: Grant
    Filed: April 6, 1999
    Date of Patent: March 18, 2003
    Assignee: Fujitsu Limited
    Inventors: Yasutoshi Tasaka, Hidefumi Yoshida, Takatoshi Mayama
  • Publication number: 20030043336
    Abstract: The invention has an object to provide a liquid crystal display in which a wide angle of view is obtained and a response time at a halftone can be shortened by regulating an alignment orientation of a liquid crystal by the use of a polymer fixation system in which a liquid crystal layer containing a polymerizable component is sealed between substrates, and the polymerizable component is polymerized while a voltage is applied to the liquid crystal layer to fix a liquid crystal alignment. A liquid crystal layer containing a polymer for regulating a pretilt angle of a liquid crystal molecule and a tilt direction at a time of driving is sealed between two substrates arranged opposite to each other.
    Type: Application
    Filed: March 28, 2002
    Publication date: March 6, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Takahiro Sasaki, Kazutaka Hanaoka, Tsutomu Seino, Yohei Nakanishi, Seiji Tanuma, Kimiaki Nakamura, Yuichi Inoue, Masakazu Shibasaki, Hideaki Tsuda, Yoshio Koike, Yasutoshi Tasaka, Hidefumi Yoshida, Kunihiro Tashiro
  • Publication number: 20030025864
    Abstract: A liquid crystal display device includes a pair of substrates, a liquid crystal between substrates and alignment layers disposed on the inner surface sides of the substrates. The alignment layer is made from a material including polyamic acid containing a diamine component and polyimide containing a diamine component different from the diamine component of the polyamic acid. The alignment layer is subjected to alignment treatment by irradiation of light. UV light can be irradiated in the oblique direction onto the alignment layer through a mask having openings. A reflecting plate can be arranged between a UV light source and the mask. Also, bank structures having a thickness from 0.1 to 0.15 &mgr;m can be provided on the alignment layer of the TFT substrate.
    Type: Application
    Filed: March 12, 2002
    Publication date: February 6, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Hideo Chida, Hidefumi Yoshida, Yasutoshi Tasaka
  • Patent number: 6512564
    Abstract: The liquid crystal display device comprising a pair of substrates with alignment layers formed thereon, and a liquid crystal filled between the substrates. Each pixel has pixel display portions CA, CB and non-display portions DA, EA, DB, EB. The pixel display portions are treated for realizing alignment in a different manner from the non-display portions and the alignment of the pixel display portions is controlled by the alignment of the non-display portions. Moreover, the alignment treatment is executed by the irradiation with ultraviolet rays in an inclined direction.
    Type: Grant
    Filed: February 25, 1998
    Date of Patent: January 28, 2003
    Assignee: Fujitsu Limited
    Inventors: Hidefumi Yoshida, Tsutomu Seino, Yasutoshi Tasaka
  • Patent number: 6501524
    Abstract: A homeotropic alignment type liquid crystal display device is provided with first and second substrates confronting each other, first and second bus lines arranged in mutually perpendicular directions on the second substrate, liquid crystals provided between the first and second substrates, and first, second and third projecting structures restricting alignment of the liquid crystals. The first projecting structures have a sloping surface which is inclined with respect to the first substrate and are provided on the first substrate in parallel with the first bus lines. The second projecting structures have a sloping surface which is inclined with respect to the second substrate and are provided on the second substrate in parallel with the first bus lines.
    Type: Grant
    Filed: August 17, 1999
    Date of Patent: December 31, 2002
    Assignee: Fujitsu Limited
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takatoshi Mayama, Seiji Tanuma, Takeshi Gotoh, Tetsuya Kobayashi, Yohei Nakanishi, Makoto Ohashi, Yoshio Koike, Arihiro Takeda
  • Publication number: 20020159014
    Abstract: A method of fabricating a liquid crystal display device including vertical alignment layers formed on the substrates. The alignment layer having a polymer realizing vertical alignment is formed on the substrate an unpolarized ultraviolet light is then irradiated in the oblique direction at an angle not more than 45 degrees with respect to the surface of the alignment layer. The ultraviolet light has an exposure energy of 30 to 120 mJ/cm2 per percent of the polymer content realizing the vertical alignment of the alignment layer. The liquid crystal can thus align substantially vertically to the surface of the alignment layer, with a pretilt, and such an alignment is realized by the irradiation of the ultraviolet light, without rubbing.
    Type: Application
    Filed: May 6, 2002
    Publication date: October 31, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Yasutoshi Tasaka, Hidefumi Yoshida, Takatoshi Mayama
  • Publication number: 20020051109
    Abstract: AC voltage of rectangular wave is applied between a pixel electrode 25A and a common electrode 23A, and the amplitude Vac of the AC voltage component and the DC voltage component Vdc thereof are changed to measure the range of optimal DC component variation &Dgr;Vdc and determine a structure or material of a liquid crystal display device so as to lower &Dgr;Vdc less than a given value, wherein &Dgr;Vdc=|Vdcb−Vdcw|, Vdcb is the value of Vdc at which the range of transmittance variation is the minimum with Vac being fixed at a value for displaying black (2V), and Vdcw is the value of Vdc at which the range of transmittance variation is the minimum with Vac being fixed at a value for displaying white (7 V). Thickness of an insulating layer 26A on the pixel electrode 25A and on the common electrode 23A are the same. Electrode crossover portions are made to be in axial symmetry. The top surface of each stripe electrode of a pixel electrode has convex shape in cross section.
    Type: Application
    Filed: August 9, 2001
    Publication date: May 2, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Yohei Nakanishi, Hidefumi Yoshida, Takashi Sasabayashi, Yasutoshi Tasaka, Tetsuya Fujikawa, Hidetoshi Sukenori
  • Publication number: 20010030726
    Abstract: There is provided a liquid crystal display which exhibits preferable viewing angle characteristics even in a diagonal viewing angle. Optical retardation films of a first type that satisfy nx>ny, nz and optical retardation films of a second type that satisfy nx≡ny>nz are used, and a setting is made to satisfy Rp−t=2×(−0.08×RLC+58 nm+&agr;) (&agr;=±30 nm) and Rt−t=(1.05±0.05)×RLC−47 nm+&bgr;(−100 nm≦&bgr;≦47 nm) where &Dgr;nd represents a retardation RLC in the liquid crystal display; Rp−t represents the sum of retardations Rp in in-plane directions of a plurality of optical retardation films; and Rt−t represents the sum of retardations Rt in the direction of the thickness of the plurality of optical retardation films.
    Type: Application
    Filed: April 3, 2001
    Publication date: October 18, 2001
    Applicant: FUJITSU LIMITED
    Inventors: Hidefumi Yoshida, Takashi Sasabayashi, Yasutoshi Tasaka, Yohei Nakanishi, Kenji Okamoto, Seiji Tanuma, Kazutaka Hanaoka, Takatoshi Mayama, Yuichi Inoue