Patents by Inventor Kazuhisa Mizusako

Kazuhisa Mizusako 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: 20210125571
    Abstract: In a liquid crystal projector, in a first liquid crystal panel corresponding to a first color, a gray scale level specified by video data specifies a first value in a first field, and a second value in a second field subsequent to the first field, and in a second liquid crystal panel corresponding to a second color, a gray scale level specified by the video data specifies the first value in the first field, and the second value in the second field. When optical responsiveness of the first liquid crystal panel is better than optical responsiveness of the second liquid crystal panel, in the second field, a liquid crystal voltage applied to the first liquid crystal panel is smaller than a liquid crystal voltage applied to the second liquid crystal panel.
    Type: Application
    Filed: October 21, 2020
    Publication date: April 29, 2021
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Toru AOKI, Daigo HOKAZONO, Kazuhisa MIZUSAKO
  • Patent number: 10444574
    Abstract: A liquid crystal display to suppress a reverse tilt domain that includes pixel electrodes, a first light-shielding film arranged in a first direction along a first side of the pixel electrodes; a second light-shielding film arranged in a second direction along a second side of the pixel electrodes, a correction unit corrects a first input image signal so that a first difference between a first voltage applied to the first pixel electrode and a second voltage applied to a second pixel electrode, and a second difference between the first voltage and a third voltage to be applied to a third pixel electrode are reduced. A width of the first light-shielding film is narrower than a width of the second light-shielding film. The correction unit corrects the first input image signal so that a decreased amount of the first difference is greater than a decreased amount of the second difference.
    Type: Grant
    Filed: July 19, 2018
    Date of Patent: October 15, 2019
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Patent number: 10380957
    Abstract: An electrooptic device includes a plurality of first pixels, a plurality of second pixels, a first supplying section that supplies a first data signal to the first pixels and drives the first pixels, a second supplying section that supplies a second data signal to the second pixels and drives the second pixels, and a controller that supplies a third data signal to the first supplying section and supplies a fourth data signal to the second supplying section. The first supplying section generates the first data signal based on the third data signal. The second supplying section generates the second data signal based on the fourth data signal. The controller individually corrects a fifth data signal serving as a source of the third data signal and a sixth data signal serving as a source of the fourth data signal and generates the third data signal and the fourth data signal.
    Type: Grant
    Filed: October 30, 2017
    Date of Patent: August 13, 2019
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Publication number: 20190033670
    Abstract: A liquid crystal display to suppress a reverse tilt domain that includes pixel electrodes, a first light-shielding film arranged in a first direction along a first side of the pixel electrodes; a second light-shielding film arranged in a second direction along a second side of the pixel electrodes, a correction unit corrects a first input image signal so that a first difference between a first voltage applied to the first pixel electrode and a second voltage applied to a second pixel electrode, and a second difference between the first voltage and a third voltage to be applied to a third pixel electrode are reduced. A width of the first light-shielding film is narrower than a width of the second light-shielding film. The correction unit corrects the first input image signal so that a decreased amount of the first difference is greater than a decreased amount of the second difference.
    Type: Application
    Filed: July 19, 2018
    Publication date: January 31, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa MIZUSAKO, Hiroyuki HOSAKA
  • Patent number: 10121400
    Abstract: A video processing circuit includes a detecting unit that detects a set of a first pixel and a second pixel adjacent to the first pixel, which is a set of pixels in which a difference between application voltages to the first pixel and the second pixel which are indicated by an input video signal is greater than or equal to a threshold; an acquisition unit that acquires information which specifies a plurality of regions of voltage-brightness characteristics which are voltage-brightness characteristics of the pixel group and in which a voltage region is separated into the plurality of regions in accordance with a slope of the voltage-brightness characteristics; and a replacing unit that replaces the application voltage to the first pixel with a voltage which is in a region other than a first region and is close to a second region.
    Type: Grant
    Filed: April 14, 2017
    Date of Patent: November 6, 2018
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Patent number: 10109254
    Abstract: A video processing circuit detects a boundary between a first pixel to which an application voltage which is a first voltage is applied, and a second pixel to which an application voltage which is a second voltage higher than the first voltage is applied, based on a video signal indicating a video which alternately switches a first video and a second video which is obtained by moving in parallel with the first video for each unit frame, corrects the application voltage such that a fringe electric field occurring at the boundary is decreased, when determining a boundary detected by the boundary detection unit in a kth unit frame does not exist in a (k?2)th unit frame, and the boundary is a boundary which is moved from a (k?1)th unit frame to the kth unit frame, and outputs the corrected video signal such that the liquid crystal panel is driven.
    Type: Grant
    Filed: January 21, 2015
    Date of Patent: October 23, 2018
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Publication number: 20180122313
    Abstract: An electrooptic device includes a plurality of first pixels, a plurality of second pixels, a first supplying section that supplies a first data signal to the first pixels and drives the first pixels, a second supplying section that supplies a second data signal to the second pixels and drives the second pixels, and a controller that supplies a third data signal to the first supplying section and supplies a fourth data signal to the second supplying section. The first supplying section generates the first data signal based on the third data signal. The second supplying section generates the second data signal based on the fourth data signal. The controller individually corrects a fifth data signal serving as a source of the third data signal and a sixth data signal serving as a source of the fourth data signal and generates the third data signal and the fourth data signal.
    Type: Application
    Filed: October 30, 2017
    Publication date: May 3, 2018
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa MIZUSAKO, Hiroyuki HOSAKA
  • Patent number: 9858890
    Abstract: A liquid crystal display device is configured so that one frame is divided into two fields and a pixel of a liquid crystal panel is driven. The liquid crystal display device performs overdrive when a gray-scale level to be supplied to the pixel is different between a previous frame and a current frame. The liquid crystal display writes a voltage corresponding to the gray-scale level of the pixel with a positive voltage in a first field, and writes a voltage corresponding to the gray-scale level to be supplied to the pixel with a negative voltage in a second field. When performing overdrive, the liquid crystal display device performs overdrive in both of the first field and the second field. Also, when performing overdrive, the liquid crystal display device corrects the gray-scale level to be supplied to the pixel.
    Type: Grant
    Filed: December 26, 2012
    Date of Patent: January 2, 2018
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Publication number: 20170316727
    Abstract: A video processing circuit includes a detecting unit that detects a set of a first pixel and a second pixel adjacent to the first pixel, which is a set of pixels in. which a difference between application voltages to the first pixel and the second pixel which are indicated by an input video signal is greater than or equal to a threshold; an acquisition unit that acquires information which specifies a plurality of regions of voltage-brightness characteristics which are voltage-brightness characteristics of the pixel group and in which a voltage region is separated into the plurality of regions in accordance with a slope of the voltage-brightness characteristics; and a replacing unit that replaces the application voltage to the first pixel with a voltage which is in a region other than a first region and is close to a second region.
    Type: Application
    Filed: April 14, 2017
    Publication date: November 2, 2017
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa MIZUSAKO, Hiroyuki HOSAKA
  • Patent number: 9607563
    Abstract: A liquid crystal display device supplies an active scan signal to each scan line while skipping a portion of a plurality of the scan lines, per one horizontal scan period, in a direction of the m-th to the first scan lines, by a first scan line drive circuit, and supplies the active scan signal to each scan line while skipping the portion of the plurality of the scan lines, per one horizontal scan period, in a direction of the m+1-th to the 2m-th scan lines, by a second scan line drive circuit. Therefore, the liquid crystal display device synchronizes with a timing of supplying the active signal with the first scan line drive circuit and the second scan line drive circuit, and supplies a data signal whose polarity is inverted to a positive polarity potential and a negative polarity potential per one horizontal scan period, to a data line.
    Type: Grant
    Filed: January 29, 2016
    Date of Patent: March 28, 2017
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Satoshi Yatabe, Kazuhisa Mizusako, Nariya Takahashi
  • Publication number: 20170025084
    Abstract: A video processing circuit detects a boundary between a first pixel to which an application voltage which is a first voltage is applied, and a second pixel to which an application voltage which is a second voltage higher than the first voltage is applied, based on a video signal indicating a video which alternately switches a first video and a second video which is obtained by moving in parallel with the first video for each unit frame, corrects the application voltage such that a fringe electric field occurring at the boundary is decreased, when determining a boundary detected by the boundary detection unit in a kth unit frame does not exist in a (k?2)th unit frame, and the boundary is a boundary which is moved from a (k?1)th unit frame to the kth unit frame, and outputs the corrected video signal such that the liquid crystal panel is driven.
    Type: Application
    Filed: January 21, 2015
    Publication date: January 26, 2017
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Publication number: 20160148585
    Abstract: A liquid crystal display device supplies an active scan signal to each scan line while skipping a portion of a plurality of the scan lines, per one horizontal scan period, in a direction of the m-th to the first scan lines, by a first scan line drive circuit, and supplies the active scan signal to each scan line while skipping the portion of the plurality of the scan lines, per one horizontal scan period, in a direction of the m+1-th to the 2m-th scan lines, by a second scan line drive circuit. Therefore, the liquid crystal display device synchronizes with a timing of supplying the active signal with the first scan line drive circuit and the second scan line drive circuit, and supplies a data signal whose polarity is inverted to a positive polarity potential and a negative polarity potential per one horizontal scan period, to a data line.
    Type: Application
    Filed: January 29, 2016
    Publication date: May 26, 2016
    Inventors: Satoshi YATABE, Kazuhisa MIZUSAKO, Nariya TAKAHASHI
  • Publication number: 20160125817
    Abstract: A video processing circuit includes a specific unit that specifies a first pixel adjacent to a second pixel which displays a higher gradation than a predetermined gradation, among the first pixels which display gradations equal to or lower than the predetermined gradation, based on the video signal in a current frame; a determination unit that determines whether or not the second pixel exists in a frame adjacent to the current frame on the time axis, in a position of the first pixel which is specified; and a correction unit that, in a case in which it is determined that the second pixel exists in the frame adjacent to the current frame, corrects the video signal in the current frame, in such a manner that a difference of an application voltage between the specified first pixel and the second pixel adjacent to the first pixel is reduced.
    Type: Application
    Filed: October 20, 2015
    Publication date: May 5, 2016
    Inventors: Kazuhisa Mizusako, Hiroyuki Hosaka
  • Patent number: 9286840
    Abstract: A liquid crystal display device supplies an active scan signal to each scan line while skipping a portion of a plurality of the scan lines, per one horizontal scan period, in a direction of the m-th to the first scan lines, by a first scan line drive circuit, and supplies the active scan signal to each scan line while skipping the portion of the plurality of the scan lines, per one horizontal scan period, in a direction of the m+1-th to the 2m-th scan lines, by a second scan line drive circuit. Therefore, the liquid crystal display device synchronizes with a timing of supplying the active signal with the first scan line drive circuit and the second scan line drive circuit, and supplies a data signal whose polarity is inverted to a positive polarity potential and a negative polarity potential per one horizontal scan period, to a data line.
    Type: Grant
    Filed: October 31, 2014
    Date of Patent: March 15, 2016
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Satoshi Yatabe, Kazuhisa Mizusako, Nariya Takahashi
  • Publication number: 20150123959
    Abstract: A liquid crystal display device supplies an active scan signal to each scan line while skipping a portion of a plurality of the scan lines, per one horizontal scan period, in a direction of the m-th to the first scan lines, by a first scan line drive circuit, and supplies the active scan signal to each scan line while skipping the portion of the plurality of the scan lines, per one horizontal scan period, in a direction of the m+1-th to the 2m-th scan lines, by a second scan line drive circuit. Therefore, the liquid crystal display device synchronizes with a timing of supplying the active signal with the first scan line drive circuit and the second scan line drive circuit, and supplies a data signal whose polarity is inverted to a positive polarity potential and a negative polarity potential per one horizontal scan period, to a data line.
    Type: Application
    Filed: October 31, 2014
    Publication date: May 7, 2015
    Inventors: Satoshi YATABE, Kazuhisa MIZUSAKO, Nariya TAKAHASHI
  • Patent number: 9001111
    Abstract: A liquid crystal display device according to the invention has an effect that burn-in and a flicker do not occur. Dummy pixels are provided around pixels of the liquid crystal display device. A first voltage higher in order than a reference voltage and a second voltage lower in order than the first voltage are applied to a pixel electrode of a liquid crystal device included in the dummy pixel while being temporally shifted. The liquid crystal display device changes, on the basis of an electric current flowing to a second opposed electrode when the first voltage is applied and an electric current flowing to the second opposed electrode when the second voltage is applied, a ratio of effective voltages of a positive voltage and a negative voltage applied to a liquid crystal device included in the pixel that displays an image.
    Type: Grant
    Filed: September 12, 2012
    Date of Patent: April 7, 2015
    Assignee: Seiko Epson Corporation
    Inventors: Kazuhisa Mizusako, Hitoshi Sasaki
  • Publication number: 20150009477
    Abstract: A light source control device and a light source control method each capable of preventing the scroll noise from occurring without being affected by the characteristics of a light modulation device, and a projector equipped with the light source control device are provided. The light source device includes a duty determination section adapted to determine a duty ratio, and a drive control section adapted to perform drive control of a plurality of solid-state light sources by generating a PWM signal having the duty ratio determined by the duty ratio determination section, and adapted to make a phase with which at least one of the solid-state light sources is driven different from a phase with which another of the solid-state light sources is driven.
    Type: Application
    Filed: September 19, 2014
    Publication date: January 8, 2015
    Inventors: Takashi TOYOOKA, Kazuhisa MIZUSAKO
  • Patent number: 8907936
    Abstract: A liquid crystal display includes liquid crystal elements in which a liquid crystal layer is sandwiched by a first electrode and a second electrode, a driving circuit configured to alternately apply higher and lower voltages than a predetermined voltage to the first electrode, and, at the same time, to apply the predetermined voltage to the second electrode, and a control circuit configured to compare a first current with a second current, the first current being obtained by excluding an instantaneous current due to a related higher voltage from currents flowing through the second electrode after the higher voltage is applied to the first electrode, and the second current being obtained by excluding an instantaneous current due to a related lower voltage from currents flowing through the second electrode after the lower voltage is applied to the first electrode, and to control the predetermined voltage based on the comparison result.
    Type: Grant
    Filed: June 3, 2010
    Date of Patent: December 9, 2014
    Assignee: Seiko Epson Corporation
    Inventor: Kazuhisa Mizusako
  • Patent number: 8872763
    Abstract: A position detecting system includes an indicating device including a photodiode that detects timing of a light pulse and a transmission unit that transmits a signal representing the timing, a plurality of light sources that emit light pulses to areas acquired by dividing a screen into a plurality of parts at timings unique to the light sources, a reception unit that receives the signal representing the timing, and a control unit that detects a position of the indicating device based on the signal representing the timing.
    Type: Grant
    Filed: January 16, 2012
    Date of Patent: October 28, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Takashi Toyooka, Tetsuro Yamazaki, Kazuhisa Mizusako
  • Patent number: 8870387
    Abstract: A light source control device and a light source control method each capable of preventing the scroll noise from occurring without being affected by the characteristics of a light modulation device, and a projector equipped with the light source control device are provided. The light source device includes a duty determination section adapted to determine a duty ratio, and a drive control section adapted to perform drive control of a plurality of solid-state light sources by generating a PWM signal having the duty ratio determined by the duty ratio determination section, and adapted to make a phase with which at least one of the solid-state light sources is driven different from a phase with which another of the solid-state light sources is driven.
    Type: Grant
    Filed: October 17, 2011
    Date of Patent: October 28, 2014
    Assignee: Seiko Epson Corporation
    Inventors: Takashi Toyooka, Kazuhisa Mizusako