Patents by Inventor Yoshinori Kiyota

Yoshinori Kiyota 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: 8564514
    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: October 29, 2002
    Date of Patent: October 22, 2013
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Shinji Tadaki, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Patent number: 8466861
    Abstract: A liquid crystal display device displays an image by stacking a plurality of liquid crystal panels, and by controlling a light transmittance with voltage application to liquid crystal of each panel, wherein during execution of voltage application to the liquid crystal of one of the panels, a voltage to the liquid crystal of the other panel serves as a non-display voltage. No image is displayed simultaneously on the two or more stacked liquid crystal panels. In the liquid crystal panel to which no voltage is applied and on which no image is displayed, the longitudinal axial direction of liquid crystal molecules coincides with the polarizing axial direction of polarizers, or is orthogonal to the polarizing axial direction; therefore, no influence is exerted on the overall double refraction, and the overall voltage-transmitted light intensity characteristic corresponds to the sum of the voltage-transmitted light intensity characteristics of the respective panels.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: June 18, 2013
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Patent number: 8253674
    Abstract: A liquid crystal panel includes a glass substrate with pixel electrodes that are arranged in a matrix shape, TFTs that are connected to the pixel electrodes, and a glass substrate with an opposing electrode and color filters that are arranged in a matrix shape. A liquid crystal layer is formed in a space between the glass substrates by filling a ferroelectric liquid crystal into the space. When writing display data, and when deleting display data that has been written, a voltage, not including 0V, that becomes a voltage potential, or in other words, a voltage that is greater than a threshold voltage at which the optical characteristic of the filled ferroelectric liquid crystal changes is applied between the opposing electrode and pixel electrodes. An image is displayed over all gradation numbers, including the low-gradation side, and the display characteristic is improved.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: August 28, 2012
    Assignee: Fujitsu Limited
    Inventors: Tetsuya Makino, Toshiaki Yoshihara, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Patent number: 8044901
    Abstract: When the applied voltages are 7 V and 5 V, a transmittance of equal to or more than 50% is obtained when conditions of |2Ps·A|?|7Clc·A| and |2Ps·A|?|5Clc·A| are satisfied among the magnitude Ps (nC/cm2) of the spontaneous polarization per unit area of the liquid crystal material, the electrode area A (cm2) of the pixels and the capacity of liquid crystal Clc (nF/cm2) per unit area, and a transmittance of equal to or more than 80% is obtained when conditions of |2Ps·A|?|4.5Clc·A| and |2Ps·A|?|3Clc·A| are satisfied thereamong. A sufficiently high transmittance is obtained without the provision of a storage capacitor.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: October 25, 2011
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Patent number: 7847913
    Abstract: A liquid crystal material is used in which the maximum angle of the optical axis change by liquid crystal molecule when a voltage of one polarity is applied is larger than 45 degrees and a condition of |2Ps·A|>|5(V)Clc·A| is satisfied where Ps (nC/cm2) is the magnitude of the spontaneous polarization per unit area, A (cm2) is the electrode area of the pixel and Clc (nF/cm2) is the liquid crystal capacity per unit area. The transmittance in the liquid crystal part is increased and excellent display can be performed without the provision of a storage capacitor. Consequently, the storage capacitor is unnecessary, so that the aperture ratio of the liquid crystal panel can be increased.
    Type: Grant
    Filed: October 17, 2007
    Date of Patent: December 7, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Patent number: 7830344
    Abstract: There is provided a liquid crystal display including a panel using a liquid crystal material having spontaneous polarization, such as ferroelectroic liquid crystal (FLC), having a faster response time suitable to display dynamic images. The FLC has the disadvantage caused by the incomplete memory effect at during driving for displaying “black” in several frames, where the light transmittance is preferably desired zero. The panel in the display are driven signals so that the driving signals are applied across the picture element, where the signals are positively or negatively offset to reference voltage of the panel.
    Type: Grant
    Filed: May 9, 2007
    Date of Patent: November 9, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Hironori Shiroto, Yoshinori Kiyota
  • Patent number: 7821610
    Abstract: Although portions of electrodes in proximity to a driver IC are covered with an insulating film, part of the electrodes is not covered with the insulating film. Thus, this insulating film absent region functions as an external voltage supply region that receives, from the outside, application of a voltage which is different from an output voltage from a driving unit. When the alignment of the initial state is disarranged, an alignment process is performed by short-circuiting all electrodes of the driving unit and applying a voltage from the outside, through the external voltage supply region, whereby the alignment is restored to the initial state with the driving unit being mounted on a liquid crystal panel.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: October 26, 2010
    Assignee: Fujitsu Limited
    Inventors: Tetsuya Makino, Shinji Tadaki, Toshiaki Yoshihara, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Patent number: 7764346
    Abstract: A liquid crystal display device comprising: a peripheral electrode 31 that is formed around the outside of a display region 1a on a liquid crystal panel 1 and that generates an orientation state that is equivalent to that of the display region 1a; and an inverted electrode 32 that is formed around the outside of the peripheral electrode 31 and that generates an orientation state that has polarity opposite to that of the display region 1a; wherein the peripheral electrode 31 and the inverted electrode 32 have bipectinate construction and are arranged on both sides of a non-oriented buffer region 33. Orientation defects that are generated in a seal are trapped inside the buffer region 33 due to the existence of the peripheral electrode 31 and inverted electrode 32 that have different growth directions, so the orientation defects do not intrude into the display region 1a.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: July 27, 2010
    Assignee: Fujitsu Limited
    Inventors: Shinji Tadaki, Yoshinori Kiyota, Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Keiichi Betsui
  • Patent number: 7724229
    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: Grant
    Filed: December 7, 2005
    Date of Patent: May 25, 2010
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Patent number: 7499012
    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: Grant
    Filed: August 31, 2004
    Date of Patent: March 3, 2009
    Assignee: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20080303990
    Abstract: A liquid crystal material is used in which the maximum angle of the optical axis change by liquid crystal molecule when a voltage of one polarity is applied is larger than 45 degrees and a condition of |2Ps·A|>|5Clc·A| is satisfied where Ps (nC/cm2) is the magnitude of the spontaneous polarization per unit area, A (cm2) is the electrode area of the pixel and Clc (nF/cm2) is the liquid crystal capacity per unit area. The transmittance in the liquid crystal part is increased and excellent display can be performed without the provision of a storage capacitor. Consequently, the storage capacitor is unnecessary, so that the aperture ratio of the liquid crystal panel can be increased.
    Type: Application
    Filed: October 17, 2007
    Publication date: December 11, 2008
    Applicant: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20080266510
    Abstract: In a liquid crystal display device which has a pair of opposing substrates having a gap filled with a liquid crystal material, with a peripheral edge portion of the paired substrates being sealed by a sealing member, between the thickness (ts) of the sealing member and the thickness (tlc) of the liquid crystal layer, a relationship of ts/tlc?2, more preferably, ts/tlc?3, is satisfied. By making a difference smaller between a volume change in the liquid crystal material due to a temperature change and a volume change in a space in which the liquid crystal is sealed, defects caused by the volume difference are restrained from occurring. In order to achieve the relationship between ts and tlc, a flat layer is placed on one or both of the substrates.
    Type: Application
    Filed: March 6, 2008
    Publication date: October 30, 2008
    Applicant: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20080192158
    Abstract: A liquid crystal display device displays an image by stacking a plurality of liquid crystal panels, and by controlling a light transmittance with voltage application to liquid crystal of each panel, wherein during execution of voltage application to the liquid crystal of one of the panels, a voltage to the liquid crystal of the other panel serves as a non-display voltage. No image is displayed simultaneously on the two or more stacked liquid crystal panels. In the liquid crystal panel to which no voltage is applied and on which no image is displayed, the longitudinal axial direction of liquid crystal molecules coincides with the polarizing axial direction of polarizers, or is orthogonal to the polarizing axial direction; therefore, no influence is exerted on the overall double refraction, and the overall voltage-transmitted light intensity characteristic corresponds to the sum of the voltage-transmitted light intensity characteristics of the respective panels.
    Type: Application
    Filed: April 1, 2008
    Publication date: August 14, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20080158141
    Abstract: In a field sequential display method the light emission intensities of the luminous colors are controlled to realize a plurality of color reproduction regions having different areas and make the color purity variable. In the case of high-resolution image display, a first control method is adopted in which in synchronism with the input of the pixel data of one of the luminous colors, the light of the one of the luminous colors is emitted and the lights of the other luminous colors are not emitted. In the case of coarse image display, a second control method is adopted in which in synchronism with the input of the pixel data of one of the luminous colors, the light of the one of the luminous colors and the lights of the other luminous colors are emitted. By the second method, the color purity is slightly decreased to suppress the visual irritation.
    Type: Application
    Filed: March 10, 2008
    Publication date: July 3, 2008
    Applicant: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Patent number: 7362404
    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: Grant
    Filed: August 31, 2004
    Date of Patent: April 22, 2008
    Assignee: Fujitsu Limited
    Inventors: Shinji Tadaki, Yoshinori Kiyota, Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20080043178
    Abstract: When the applied voltages are 7 V and 5 V, a transmittance of equal to or more than 50% is obtained when conditions of |2Ps·A|?|7Clc·A| and |2Ps·A|?|5Clc·A | are satisfied among the magnitude Ps (nC/cm2) of the spontaneous polarization per unit area of the liquid crystal material, the electrode area A (cm2) of the pixels and the capacity of liquid crystal Clc (nF/cm2) per unit area, and a transmittance of equal to or more than 80% is obtained when conditions of |2Ps·A|?|4.5Clc·A| and |2Ps·A|?|3Clc·A| are satisfied thereamong. A sufficiently high transmittance is obtained without the provision of a storage capacitor.
    Type: Application
    Filed: October 17, 2007
    Publication date: February 21, 2008
    Applicant: Fujitsu Limited
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20080042961
    Abstract: Although portions of electrodes in proximity to a driver IC are covered with an insulating film, part of the electrodes is not covered with the insulating film. Thus, this insulating film absent region functions as an external voltage supply region that receives, from the outside, application of a voltage which is different from an output voltage from a driving unit. When the alignment of the initial state is disarranged, an alignment process is performed by short-circuiting all electrodes of the driving unit and applying a voltage from the outside, through the external voltage supply region, whereby the alignment is restored to the initial state with the driving unit being mounted on a liquid crystal panel.
    Type: Application
    Filed: October 19, 2007
    Publication date: February 21, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Tetsuya Makino, Shinji Tadaki, Toshiaki Yoshihara, Hironori Shiroto, Yoshinori Kiyota, Shigeo Kasahara, Keiichi Betsui
  • Publication number: 20080018588
    Abstract: In a predetermined period (one frame or one subframe), a backlight is lit between the mid-point of primary data-writing scanning and the mid-point of secondary data-writing scanning for each of lighting regions of which the backlight is divided into four. When the time required for the data-writing scanning is 50% of the predetermined time, the ratio of the time the liquid crystal panel is in the transmission state to the time the backlight is lit (panel-on rate) is high at 93.8%. The ratio of the brightness gradient (luminance at the center of the display area/luminance at the edge of the display area) is low at 1.14 to one. If the backlight is divided into 10 and lit, the panel-on rate can be increased to 97.5%, and the ratio of the brightness gradient can be reduced to 1.05 to one.
    Type: Application
    Filed: September 28, 2007
    Publication date: January 24, 2008
    Inventors: Toshiaki Yoshihara, Tetsuya Makino, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20080001878
    Abstract: A liquid crystal panel has: a glass substrate with pixel electrodes that are arranged in a matrix shape, and TFTs that are connected to the pixel electrodes; and a glass substrate with an opposing electrode and color filters that are arranged in a matrix shape. A liquid crystal layer is formed in a space between an oriented film and oriented film by filling a ferroelectric liquid crystal into the space. When writing display data, and when deleting display data that has been written, a voltage, not including 0V, that becomes a voltage potential, or in other words, a voltage that is greater than a threshold voltage at which the optical characteristic of the filled ferroelectric liquid crystal changes is applied between the opposing electrode and pixel electrodes. An image is displayed over all gradation numbers, including the low-gradation side, and the display characteristic is improved.
    Type: Application
    Filed: September 6, 2007
    Publication date: January 3, 2008
    Applicant: Fujitsu Limited
    Inventors: Tetsuya Makino, Toshiaki Yoshihara, Shinji Tadaki, Hironori Shiroto, Yoshinori Kiyota, Keiichi Betsui
  • Publication number: 20080002120
    Abstract: A liquid crystal display device comprising: a peripheral electrode 31 that is formed around the outside of a display region 1a on a liquid crystal panel 1 and that generates an orientation state that is equivalent to that of the display region 1a; and an inverted electrode 32 that is formed around the outside of the peripheral electrode 31 and that generates an orientation state that has polarity opposite to that of the display region 1a; wherein the peripheral electrode 31 and the inverted electrode 32 have bipectinate construction and are arranged on both sides of a non-oriented buffer region 33. Orientation defects that are generated in a seal are trapped inside the buffer region 33 due to the existence of the peripheral electrode 31 and inverted electrode 32 that have different growth directions, so the orientation defects do not intrude into the display region 1a.
    Type: Application
    Filed: September 7, 2007
    Publication date: January 3, 2008
    Applicant: Fujitsu Limited
    Inventors: Shinji Tadaki, Yoshinori Kiyota, Toshiaki Yoshihara, Hironori Shiroto, Tetsuya Makino, Keiichi Betsui