Patents by Inventor Hironori Shiroto

Hironori Shiroto 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: 7161652
    Abstract: The present invention provides a manufacturing method of a liquid crystal display device capable of achieving uniform alignment of monostable ferroelectric liquid crystal having spontaneous polarization, and provides the liquid crystal display device. The liquid crystal (monostable ferroelectric liquid crystal having spontaneous polarization) showing a phase sequence, either isotropic liquid phase-cholesteric phase-chiral smectic C phase, isotropic liquid phase-chiral nematic phase-chiral smectic C phase, or isotropic liquid phase-cholesteric phase-smectic A phase-chiral smectic C phase, from a high temperature side to a low temperature side, is sandwiched between two glass substrates having transparent electrodes and alignment films whose pretilt angle is not more than 2° and rubbing directions are parallel.
    Type: Grant
    Filed: July 29, 2003
    Date of Patent: January 9, 2007
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Hironori Shiroto, Shinji Tadaki, Tetsuya Makino, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20060244895
    Abstract: The present invention provides a manufacturing method of a liquid crystal display device capable of achieving uniform alignment of monostable ferroelectric liquid crystal having spontaneous polarization, and provides the liquid crystal display device. The liquid crystal (monostable ferroelectric liquid crystal having spontaneous polarization) showing a phase sequence, either isotropic liquid phase—cholesteric phase—chiral smectic C phase, isotropic liquid phase—chiral nematic phase—chiral smectic C phase, or isotropic liquid phase—cholesteric phase—smectic A phase—chiral smectic C phase, from a high temperature side to a low temperature side, is sandwiched between two glass substrates having transparent electrodes and alignment films whose pretilt angle is not more than 2° and rubbing directions are parallel.
    Type: Application
    Filed: June 30, 2006
    Publication date: November 2, 2006
    Inventors: Toshiaki Yoshihara, Hironori Shiroto, Shinji Tadaki, Tetsuya Makino, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Patent number: 7081873
    Abstract: In a liquid crystal display device that uses a liquid crystal material having spontaneous polarization and is actively driven by a TFT, a voltage corresponding to image data is applied twice by driving the TFT of each pixel electrode on a line by line basis of a liquid crystal panel, during writing in one frame. During erasure in one frame, voltage application to liquid crystal by batch selection of all the pixel electrodes is performed three times. With this three times of voltage application, it is possible to achieve a black display state in each pixel and make the stored charge amount at the liquid crystal in each pixel substantially zero.
    Type: Grant
    Filed: September 5, 2001
    Date of Patent: July 25, 2006
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Shinji Tadaki, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota
  • Publication number: 20060092122
    Abstract: A voltage corresponding to desired image data is applied to a ferroelectric liquid crystal having a spontaneous polarization at a predetermined cycle to rewrite the displayed image (period A), and then, all voltages applied to the ferroelectric liquid crystal are removed (timing C) to retain the displayed image before the removal (period B). A gate selection period (voltage application period to the ferroelectric liquid crystal) t2 before stopping the voltage application is set longer than a gate selection period (voltage application period to the ferroelectric liquid crystal) t1 in the normal display. Increasing the voltage application period to the ferroelectric liquid crystal provides a sufficient response of the liquid crystal during the gate selection period, thereby realizing high memory ability.
    Type: Application
    Filed: December 7, 2005
    Publication date: May 4, 2006
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20060092186
    Abstract: A color display is performed by carrying out a switching between a first driving system in which the OFF timing of a light source and the end timing of a data scanning agree with each other and a second driving system in which the OFF timing of a light source and the end timing of a data scanning do not agree with each other. In case where a response time of a liquid crystal from a transmission state to a light-shielding state is sufficiently short, a color display is performed by using the first driving system to decrease a light-emitting time of a light source. On the other hand, in case where the response time of the liquid crystal from the transmission state to the light-shielding state is increased, a color display is performed by using the second driving system.
    Type: Application
    Filed: December 7, 2005
    Publication date: May 4, 2006
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20050219456
    Abstract: In a liquid crystal display device, one or a plurality of partition walls adhering to the two substrates are provided in a region between the adhesive member for sealing the peripheral portions of the two substrates and a display region located inside the adhesive member so as to reduce stress applied to the liquid crystal substance. Even when stress is applied to the liquid crystal substance in the peripheral portion of the substrate, the stress is reduced by the partition wall and is not transmitted to the display region on the opposite side of the partition wall. Therefore, even when a crack occurs in the peripheral portion of the substrate due to the stress, the propagation of the crack is stopped by the partition wall, and the crack does not enter the display region.
    Type: Application
    Filed: August 31, 2004
    Publication date: October 6, 2005
    Inventors: Shinji Tadaki, Yoshinori Kiyota, Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20050212737
    Abstract: After rewriting the displayed image by applying a voltage corresponding to desired image data to a ferroelectric liquid crystal through TFTs at a predetermined cycle, the application of voltage to the ferroelectric liquid crystal is stopped, and the image displayed just before stopping the application of voltage is retained. In this memory display period, a gate-off voltage is applied to turn off the TFTs. In this memory display period, the emission intensity of a back-light is lowered compared to that in a normal display period. Before stopping the application of voltage to the ferroelectric liquid crystal, a voltage corresponding to an image to be displayed after stopping the application of voltage is applied. Before resuming the application of voltage corresponding to the image data to the ferroelectric liquid crystal, a voltage for causing all pixels to display black image is applied.
    Type: Application
    Filed: August 31, 2004
    Publication date: September 29, 2005
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Patent number: 6888610
    Abstract: A liquid crystal layer is formed by filling a space between alignment films provided on both glass substrates with a ferroelectric liquid crystal material having a spontaneous polarization. This ferroelectric liquid crystal exhibits a monostable state in which the average molecular axis of the liquid crystal molecular director is present in substantially one direction in the absence of an applied voltage. When a voltage of a first polarity is applied, the average molecular axis tilts from the monostable position to one side at an angle corresponding to the magnitude of the applied voltage, while, when a voltage of a second polarity having the opposite characteristic to the first polarity is applied, the average molecular axis tilts from the monostable position to a side opposite to the application of the voltage of the first polarity. A maximum tilt angle in the application of the voltage of the first polarity is not less than 35°, more preferably not less than 450°.
    Type: Grant
    Filed: January 16, 2003
    Date of Patent: May 3, 2005
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Keiichi Betsui
  • Patent number: 6876424
    Abstract: A liquid crystal display in which a liquid crystal, which has a spontaneous polarization of a magnitude of not more than ½ of a maximum quantity of charge that is injected to each pixel when the switching element is turned on, is filled between alignment films formed on respective glass substrates, so as to form a liquid crystal layer thereby to drive the liquid crystal by using a lower applied voltage.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: April 5, 2005
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota
  • Patent number: 6873311
    Abstract: A liquid crystal display unit includes a liquid crystal panel having a plurality of liquid crystal pixels and a plurality of switching elements provided in correspondence to the respective pixels. A back light disposed at the back of the liquid crystal panel and guides red, green, and blue light to the surface thereof; an image memory for storing pixel data PD to be displayed on the respective pixels; an inverted data generating circuit for generating inverted pixel data #PD of the respective pixel data PD; and a control signal generating circuit and a data driver wherein first scanning for writing the pixel data PD with respect to individual pixels of the liquid crystal panel during each period in which red, green, and blue light are emitted in time-sharing manner, and second scanning for writing the inverted pixel data #PD with respect thereto are carried out in this order.
    Type: Grant
    Filed: March 19, 1998
    Date of Patent: March 29, 2005
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Akihiro Mochizuki, Hironori Shiroto, Tetsuya Makino, Yoshinori Kiyota
  • Publication number: 20050062708
    Abstract: In a sub-frame of each color, the time required for each data scanning is 25% of the sub-frame, and the time between two times of data scanning is also 25% of the sub-frame. In a sub-frame of each color, a back-light is turned on between the intermediate timing in the first (first-half) data scanning and the intermediate timing in the second (second-half) data scanning. The ON time of the back-light is 50% of the sub-frame, and the ratio of time (panel ON rate) in which a liquid crystal panel is in a transmission state (ON) to the time in which the back-light is turned on is 88%, and thus high light utilization efficiency is achieved.
    Type: Application
    Filed: February 20, 2004
    Publication date: March 24, 2005
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Patent number: 6828954
    Abstract: A liquid crystal display device including a liquid crystal panel having a plurality of liquid crystal pixels and a plurality of switching elements provided to correspond to the respective liquid crystal pixels; a back-light, disposed on the rear face of the liquid crystal panel, for emitting red, green and blue lights in a time-divided manner; and a data driver and a scan driver for switching the respective switching elements according to red, green and blue data of the respective pixels, in which the light emitting area of the back-light is divided into a plurality of light emitting areas and the intensity of light to be emitted from each of the divided light emitting areas is adjusted by a back-light control circuit and drive power source so as to compensate for differences in the light transmittance of the liquid crystal panel.
    Type: Grant
    Filed: March 6, 2001
    Date of Patent: December 7, 2004
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota
  • Publication number: 20040041975
    Abstract: The present invention provides a manufacturing method of a liquid crystal display device capable of achieving uniform alignment of monostable ferroelectric liquid crystal having spontaneous polarization, and provides the liquid crystal display device. The liquid crystal (monostable ferroelectric liquid crystal having spontaneous polarization) showing a phase sequence, either isotropic liquid phase-cholesteric phase-chiral smectic C phase, isotropic liquid phase-chiral nematic phase-chiral smectic C phase, or isotropic liquid phase-cholesteric phase-smectic A phase-chiral smectic C phase, from a high temperature side to a low temperature side, is sandwiched between two glass substrates having transparent electrodes and alignment films whose pretilt angle is not more than 2° and rubbing directions are parallel.
    Type: Application
    Filed: July 29, 2003
    Publication date: March 4, 2004
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Yoshihara, Hironori Shiroto, Shinji Tadaki, Tetsuya Makino, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20030156243
    Abstract: A liquid crystal layer is formed by filling a space between alignment films provided on both glass substrates with a ferroelectric liquid crystal material having a spontaneous polarization. This ferroelectric liquid crystal exhibits a monostable state in which the average molecular axis of the liquid crystal molecular director is present in substantially one direction in the absence of an applied voltage. When a voltage of a first polarity is applied, the average molecular axis tilts from the monostable position to one side at an angle corresponding to the magnitude of the applied voltage, while, when a voltage of a second polarity having the opposite characteristic to the first polarity is applied, the average molecular axis tilts from the monostable position to a side opposite to the application of the voltage of the first polarity. A maximum tilt angle in the application of the voltage of the first polarity is not less than 35°, more preferably not less than 450°.
    Type: Application
    Filed: January 16, 2003
    Publication date: August 21, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Keiichi Betsui
  • Patent number: 6600544
    Abstract: A liquid crystal layer is formed by filing the space between alignment films formed on two glass substrates, respectively, with a ferroelectric liquid crystal having spontaneous polarization. When the maximum charge amount injected to each pixel by the switching of a switching element, the area of each pixel electrode and the magnitude of the spontaneous polarization of the ferroelectric liquid crystal per unit area are denoted as Q, A, and PS, respectively, the relation 2PS·A>Q is established. A cone angle 2&thgr; (&thgr;: tilt angle) of the ferroelectric liquid crystal is not smaller than 45°. It is possible to use a liquid crystal material having large spontaneous polarization, and a high-speed response is realized even when a low voltage is applied to the liquid crystal material.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: July 29, 2003
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Keiichi Betsui, Hironori Shiroto
  • Patent number: 6570554
    Abstract: A liquid crystal display in which: after a back-light has emitted three-color light rays of red, green and blue sequentially color by color, the back-light is turned off for a predetermined time, or the back-light is controlled so that, in three consecutive frames, the orders of light emissions of the respective colors carried out in respective sub-frames are not coincident with each other, thereby to reduce degradation in the image quality that occurs at the outline portion of an animation picture when it is displayed.
    Type: Grant
    Filed: September 8, 2000
    Date of Patent: May 27, 2003
    Assignee: Fujitsu Limited
    Inventors: Tetsuya Makino, Toshiaki Yoshihara, Hironori Shiroto, Yoshinori Kiyota
  • Publication number: 20030043103
    Abstract: In a liquid crystal display device that uses a liquid crystal material having spontaneous polarization and is actively driven by a TFT, a voltage corresponding to image data is applied twice by driving the TFT of each pixel electrode on a line by line basis of a liquid crystal panel, during writing in one frame. During erasure in one frame, voltage application to liquid crystal by batch selection of all the pixel electrodes is performed three times. With this three times of voltage application, it is possible to achieve a black display state in each pixel and make the stored charge amount at the liquid crystal in each pixel substantially zero.
    Type: Application
    Filed: October 29, 2002
    Publication date: March 6, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Yoshihara, Shinji Tadaki, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20030011739
    Abstract: A liquid crystal layer is formed by filing the space between alignment films formed on two glass substrates, respectively, with a ferroelectric liquid crystal having spontaneous polarization. When the maximum charge amount injected to each pixel by the switching of a switching element, the area of each pixel electrode and the magnitude of the spontaneous polarization of the ferroelectric liquid crystal per unit area are denoted as Q, A, and PS, respectively, the relation 2PS·A>Q is established. A cone angle 2&thgr; (&thgr;: tilt angle) of the ferroelectric liquid crystal is not smaller than 45°. It is possible to use a liquid crystal material having large spontaneous polarization, and a high-speed response is realized even when a low voltage is applied to the liquid crystal material.
    Type: Application
    Filed: December 20, 2001
    Publication date: January 16, 2003
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Yoshihara, Keiichi Betsui, Hironori Shiroto
  • Publication number: 20020154078
    Abstract: In a liquid crystal display device that uses a liquid crystal material having spontaneous polarization and is actively driven by a TFT, a voltage corresponding to image data is applied twice by driving the TFT of each pixel electrode on a line by line basis of a liquid crystal panel, during writing in one frame. During erasure in one frame, voltage application to liquid crystal by batch selection of all the pixel electrodes is performed three times. With this three times of voltage application, it is possible to achieve a black display state in each pixel and make the stored charge amount at the liquid crystal in each pixel substantially zero.
    Type: Application
    Filed: September 5, 2001
    Publication date: October 24, 2002
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Yoshihara, Shinji Tadaki, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota
  • Patent number: 6395352
    Abstract: When a photopolymerization compound (molecular weight: not less than 300) having at least two ultraviolet light sensitive portions in its molecular structure is mixed with ferroelectric liquid crystal and an exposure to ultraviolet light is performed, a continuous structure is formed over almost whole length between two glass substrates, and a continuous twisted structure is formed between the glass substrates in the state of liquid crystal molecular orientation. Before the exposure to ultraviolet light, the photopolymerization compound does not exhibit satisfactory compatibility with the ferroelectric liquid crystal to be mixed, but exhibits phase separation in the mixed state. The ferroelectric liquid crystal has a bookshelf layer structure.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: May 28, 2002
    Assignee: Fujitsu Limited
    Inventors: Akihiro Mochizuki, Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Yoshinori Kiyota