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: 20070008476
    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 ?Vdc and determine a structure or material of a liquid crystal display device so as to lower ?Vdc less than a given value, wherein ?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: September 15, 2006
    Publication date: January 11, 2007
    Inventors: Yohei Nakanishi, Hidefumi Yoshida, Takashi Sasabayashi, Yasutoshi Tasaka, Tetsuya Fujikawa, Hidetoshi Sukenori
  • Publication number: 20070008444
    Abstract: In a liquid crystal display device in which in order to prevent image sticking in a half tone type MVA using a floating sub-pixel, a second TFT is provided between a sub-pixel directly connected to a TFT and the floating sub-pixel, its alignment is improved and a display quality is improved. A control capacitance electrode of an adjacent pixel is extended to provide an alignment control electrode in a corner portion of a pixel in which a propagation distance of liquid crystal alignment is long, and the propagation distance of the liquid crystal alignment is shortened, and at the same time, a slit part is formed of electrodes different from each other in voltage polarity to stabilize the alignment.
    Type: Application
    Filed: March 24, 2006
    Publication date: January 11, 2007
    Inventors: Yohei Nakanishi, Hidefumi Yoshida, Yasutoshi Tasaka
  • Publication number: 20060262261
    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: July 31, 2006
    Publication date: November 23, 2006
    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: 7136131
    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 ?Vdc and determine a structure or material of a liquid crystal display device so as to lower ?Vdc less than a given value, wherein ?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: Grant
    Filed: December 20, 2005
    Date of Patent: November 14, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yohei Nakanishi, Hidefumi Yoshida, Takashi Sasabayashi, Yasutoshi Tasaka, Tetsuya Fujikawa, Hidetoshi Sukenori
  • Patent number: 7133099
    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: June 14, 2004
    Date of Patent: November 7, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hidefumi Yoshida, Tsutomu Seino, Yasutoshi Tasaka
  • Publication number: 20060244881
    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: June 21, 2006
    Publication date: November 2, 2006
    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: 20060227272
    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 ?m can be provided on the alignment layer of the TFT substrate.
    Type: Application
    Filed: June 9, 2006
    Publication date: October 12, 2006
    Inventors: Hideo Chida, Hidefumi Yoshida, Yasutoshi Tasaka
  • Publication number: 20060227266
    Abstract: The invention relates to a reflective or transflective liquid crystal display having alignment regulating structures and provides a liquid crystal display capable of achieving high display quality on which no display irregularity attributable to an irregularity of the cell thickness is visually perceived.
    Type: Application
    Filed: January 17, 2006
    Publication date: October 12, 2006
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Yasutoshi Tasaka, Hidefumi Yoshida
  • Publication number: 20060215066
    Abstract: The invention relates to a substrate for a liquid crystal display, a liquid crystal display having the substrate, and a method of driving the display and provides a substrate for a liquid crystal display which allow high display characteristics to be achieved, a liquid crystal display having the substrate, and a method of driving the display. The substrate includes two TFTs having gate electrodes connected to a gate bus line and drain electrodes connected to a drain bus line, a pixel electrode connected to a source electrode, a pixel electrode connected to another source electrode and separated from the pixel electrode, another TFT having a gate electrode connected to another gate bus line and a source electrode connected to the pixel electrode, and a buffer capacitor portion having a buffer capacitor electrode connected to another drain electrode and another buffer capacitor electrode connected to a storage capacitor bus line.
    Type: Application
    Filed: November 3, 2005
    Publication date: September 28, 2006
    Inventors: Kazuya Ueda, Tsuyoshi Kamada, Yohei Nakanishi, Hidefumi Yoshida, Hideaki Tsuda, Masakazu Shibasaki, Yasutoshi Tasaka
  • Publication number: 20060209237
    Abstract: A semi-transparent-type liquid crystal display device comprises a liquid crystal panel including a first substrate, a second substrate disposed behind the first substrate, and a liquid crystal layer confined between the first and second substrates, the liquid crystal panel being formed with picture element regions each having a filter of any of red, green and blue color, a backlight source disposed behind the liquid crystal panel, and a reflection member disposed further behind the backlight source, each of the plurality of picture element regions including therein a reflection region and a transmission region, wherein, in each of the picture element regions, the color filter is provided with an opening in correspondence to the reflection region, the opening provided in the filter of the green color having the largest area and having an area ratio of 50% or larger but equal to or smaller than 100% with respect to the reflection region.
    Type: Application
    Filed: November 23, 2005
    Publication date: September 21, 2006
    Inventors: Kunihiro Tashiro, Yasutoshi Tasaka, Hidefumi Yoshida, Manabu Sawasaki, Tomonori Tanose
  • Patent number: 7110074
    Abstract: A liquid crystal display device including a first substrate on which a first electrode and a bus line for transmitting a signal to the first electrode are formed; a second substrate on which a second electrode is formed; and domain defining projections provided on one of the first substrate and the second substrate. A plurality of domain defining slits are provided on the electrode on the other of the first substrate and the second substrate to be aligned on a straight line, and liquid crystal having negative dielectric anisotropy is sealed between the first substrate and the second substrate. A width of a bus line opposite side end of a first slit of the plurality of slits, that is positioned closest to the bus line, is set smaller than a width of a bus line side end of a second slit positioned adjacent to the first slit.
    Type: Grant
    Filed: March 2, 2004
    Date of Patent: September 19, 2006
    Assignee: Sharp Kabushiki Kaisha
    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: 7095473
    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 ?Vdc and determine a structure or material of a liquid crystal display device so as to lower ?Vdc less than a given value, wherein ?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: Grant
    Filed: December 29, 2003
    Date of Patent: August 22, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yohei Nakanishi, Hidefumi Yoshida, Takashi Sasabayashi, Yasutoshi Tasaka, Tetsuya Fujikawa, Hidetoshi Sukenori
  • Patent number: 7081935
    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 ?m can be provided on the alignment layer of the TFT substrate.
    Type: Grant
    Filed: March 12, 2002
    Date of Patent: July 25, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hideo Chida, Hidefumi Yoshida, Yasutoshi Tasaka
  • Publication number: 20060125970
    Abstract: The invention relates to a liquid crystal display used as a display section of an electronic apparatus and a method of manufacturing the same, and it is aimed at providing a liquid crystal display which can achieve high viewing angle characteristics and a method of manufacturing the same. A configuration is employed which includes a pair of substrates provided opposite to each other, a liquid crystal sealed between the pair of substrates, protrusions formed on at least one of the pair of substrates for regulating the alignment of the liquid crystal, and a plurality of pixel regions having both of a first area in which the protrusions are disposed at first intervals a2 and which has a first threshold voltage for driving of the liquid crystal and a second area in which the protrusions are disposed at second intervals a2 smaller than the first intervals and which has a second threshold voltage lower than the first threshold voltage.
    Type: Application
    Filed: December 12, 2005
    Publication date: June 15, 2006
    Inventors: Hiroyasu Inoue, Kazuya Ueda, Yasutoshi Tasaka, Hidefumi Yoshida, Kunihiro Tashiro, Tsuyoshi Kamada, Kimiaki Nakamura
  • Publication number: 20060125992
    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: February 2, 2006
    Publication date: June 15, 2006
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi
  • Publication number: 20060103801
    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 ?Vdc and determine a structure or material of a liquid crystal display device so as to lower ?Vdc less than a given value, wherein ?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: December 20, 2005
    Publication date: May 18, 2006
    Inventors: Yohei Nakanishi, Hidefumi Yoshida, Takashi Sasabayashi, Yasutoshi Tasaka, Tetsuya Fujikawa, Hidetoshi Sukenori
  • Publication number: 20060087605
    Abstract: The invention relates to a liquid crystal display used as a display section of an electronic apparatus and a method of manufacturing the same, and it is aimed at providing a liquid crystal display which can achieve high viewing angle characteristics and a method of manufacturing the same. A configuration is employed which includes a pair of substrates provided opposite to each other, a liquid crystal sealed between the pair of substrates, protrusions formed on at least one of the pair of substrates for regulating the alignment of the liquid crystal, and a plurality of pixel regions having both of a first area in which the protrusions are disposed at first intervals a2 and which has a first threshold voltage for driving of the liquid crystal and a second area in which the protrusions are disposed at second intervals a2 smaller than the first intervals and which has a second threshold voltage lower than the first threshold voltage.
    Type: Application
    Filed: December 12, 2005
    Publication date: April 27, 2006
    Inventors: Takashi Sasabayashi, Arihiro Takeda, Hiroyasu Inoue, Kazuya Ueda, Yoshio Koike, Hideaki Tsuda, Yasutoshi Tasaka, Hidefumi Yoshida, Kunihiro Tashiro, Tsuyoshi Kamada, Kimiaki Nakamura
  • Patent number: 7023516
    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: Grant
    Filed: April 7, 2003
    Date of Patent: April 4, 2006
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Hidefumi Yoshida, Yasutoshi Tasaka, Takashi Sasabayashi, Takahiro Sasaki, Arihiro Takeda, Kazuya Ueda
  • Publication number: 20060061715
    Abstract: A semi-transmissive liquid crystal display device is formed by sealing liquid crystal of negative dielectric anisotropy between a TFT substrate and a counter substrate, and has a transmission region controlling transmitted light and a reflection region controlling reflected light. Moreover, a reflecting electrode and a transparent electrode on the TFT substrate are covered with a first vertical orientation film, and a common electrode on the counter substrate is covered with a second vertical orientation film. Only the entire second vertical orientation film and the first vertical orientation film in the transmission region are modified by light, a pretilt angle of liquid crystal molecules on an interface between the first and second vertical orientation films is 45° or more, and the liquid crystal molecules in the transmission region are subjected to bend orientation.
    Type: Application
    Filed: January 28, 2005
    Publication date: March 23, 2006
    Inventors: Kunihiro Tashiro, Yasutoshi Tasaka, Hidefumi Yoshida
  • Publication number: 20060055858
    Abstract: To provide a liquid crystal display device of high image quality, and a manufacturing method therefor. A polymerizable compound in a liquid crystal composition is polymerized in a state that liquid crystal molecules present in a gap between a pixel electrode and at least either one of signal electrodes and scanning electrodes are tilted in a direction from the at least either one of the signal electrodes and the scanning electrodes toward the pixel electrode. Preferably, the amount of the polymerizable compound remaining in the liquid crystal phase after the polymerization is not more than 0.05 parts by weight per 100 parts by weight of the liquid crystal. In a seal section surrounding the liquid crystal layer, a second seal wall is preferably provided at a position opposite to the liquid crystal injection inlet in the non-display section.
    Type: Application
    Filed: February 22, 2005
    Publication date: March 16, 2006
    Inventors: Yohei Nakanishi, Yuichi Inoue, Kazutaka Hanaoka, Hidefumi Yoshida, Yasutoshi Tasaka, Kunihiro Tashiro