Patents by Inventor Takayuki Mizunaga

Takayuki Mizunaga 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: 11967294
    Abstract: A common electrode driver includes an inverting amplifier including a first resistor, a second resistor, and an operational amplifier, and a resistance ratio adjustment circuit that adjusts, in accordance with a length of one horizontal scan period, a resistance ratio being a ratio of a resistance value of the second resistor to a resistance value of the first resistor. A feedback voltage is provided to one end of the first resistor. The resistance ratio adjustment circuit sets the resistance ratio when second driving is performed, in which a length of one horizontal scan period is a second time longer than a first time, to be smaller than the resistance ratio when first driving is performed, in which a length of one horizontal scan period is the first time.
    Type: Grant
    Filed: May 1, 2023
    Date of Patent: April 23, 2024
    Assignee: Sharp Display Technology Corporation
    Inventors: Masaki Uehata, Yasuki Mori, Kohji Saitoh, Takayuki Mizunaga, Kazuya Kondoh, Takashi Nojima, Kazuhisa Yoshimoto, Kosuke Kawamoto, Hiroyuki Kito, Kazuki Nakamichi
  • Publication number: 20240005885
    Abstract: A common electrode driver includes an inverting amplifier including a first resistor, a second resistor, and an operational amplifier, and a resistance ratio adjustment circuit that adjusts, in accordance with a length of one horizontal scan period, a resistance ratio being a ratio of a resistance value of the second resistor to a resistance value of the first resistor. A feedback voltage is provided to one end of the first resistor. The resistance ratio adjustment circuit sets the resistance ratio when second driving is performed, in which a length of one horizontal scan period is a second time longer than a first time, to be smaller than the resistance ratio when first driving is performed, in which a length of one horizontal scan period is the first time.
    Type: Application
    Filed: May 1, 2023
    Publication date: January 4, 2024
    Applicant: Sharp Display Technology Corporation
    Inventors: Masaki UEHATA, Yasuki MORI, Kohji SAITOH, Takayuki MIZUNAGA, Kazuya KONDOH, Takashi NOJIMA, Kazuhisa YOSHIMOTO, Kosuke KAWAMOTO, Hiroyuki KITO, Kazuki NAKAMICHI
  • Publication number: 20190197943
    Abstract: A display control apparatus is configured to perform display control in accordance with image data and includes a first drive circuit configured to perform first display control in accordance with a first image signal denoting part of the image data, a second drive circuit configured to perform second display control in accordance with a second image signal denoting another part of the image data, a signal line connected to the first drive circuit and the second drive circuit and configured to transmit a first signal denoting a timing related to control of the first drive circuit and the second drive circuit. The second drive circuit transmits a second signal over the signal line with the second signal being multiplexed on the first signal, the second signal denoting information generated in accordance with the second image signal.
    Type: Application
    Filed: December 20, 2018
    Publication date: June 27, 2019
    Inventor: TAKAYUKI MIZUNAGA
  • Patent number: 9642257
    Abstract: The liquid crystal display device includes a liquid crystal panel including a display area for displaying images and a non-display area other than the display area, a rigid board configured to connect with an external signal source, and a flexible board. The liquid crystal panel and the flexible board are arranged in a first direction. A direction perpendicular to the first direction and along a plate surface of the liquid crystal panel is a second direction. The flexible board is larger in a dimension in the second direction than the rigid board, and includes an end portion including at least an outer portion located outside of the rigid board in the second direction, and a middle portion located about a middle of the flexible board with respect to the end portion in the second direction. The end portion is larger in dimension in the first direction than the middle portion.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: May 2, 2017
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Toru Kuriyama, Hideki Morii, Hirofumi Miyamoto, Takayuki Mizunaga, Yuta Ueyama, Toshihiro Yanagi
  • Patent number: 9495929
    Abstract: A shift register is configured so that each of first and second intermediate stages includes (i) a first input terminal supplied with a clock signal, (ii) a second input terminal supplied with a clock signal different in phase from the clock signal supplied to the first input terminal, (iii) an output terminal connected to the first input terminal via an output transistor, and (iv) a setting circuit, which is connected to the second input terminal and the output transistor, for setting an electric potential of a control terminal of the output transistor, the second intermediate stage includes a control circuit which is (i) connected to the setting circuit of the second intermediate stage and (ii) supplied with a control signal, an operation period (i) starts at a time when a shift start signal supplied to an initial stage is activated and (ii) ends at a time when an output of a final stage changes from activation to inactivation, and when the clock signal supplied to the first input terminal of the second int
    Type: Grant
    Filed: March 5, 2013
    Date of Patent: November 15, 2016
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Satoshi Horiuchi, Shinya Tanaka, Akira Tagawa, Yasuaki Iwase, Takayuki Mizunaga, Akihisa Iwamoto
  • Publication number: 20160210891
    Abstract: A liquid crystal display device capable of reproducing colors faithfully is provided. The liquid crystal display device includes a color gamut conversion unit that generates an RGB signal for a liquid crystal panel (RGBout), which is provided to a liquid crystal panel, by converting data values of respective colors included in an input RGB signal (RGBin) in accordance with the color gamut of the input RGB signal (RGBin) and the color gamut of the liquid crystal panel. When the color gamut of the input RGB signal (RGBin) is included within the color gamut of the liquid crystal panel, colors represented by the input RGB signal (RGBin) are faithfully reproduced on the liquid crystal panel by providing the RGB signal for liquid crystal panel generated by the color gamut conversion unit to the liquid crystal panel.
    Type: Application
    Filed: July 17, 2014
    Publication date: July 21, 2016
    Applicant: Sharp Kabushiki Kaisha
    Inventors: Xiaomang ZHANG, Toshihiro YANAGI, Takae ITOU, Hideki MORII, Takayuki MIZUNAGA, Keishi NISHIKUBO
  • Patent number: 9311881
    Abstract: Provided are: a liquid crystal display device capable of rapidly removing residual electric charges in a panel when a power supply is turned off, and in particular, suitable for a case where IGZO-GDM is adopted; and a driving method of the liquid crystal display device. In the liquid crystal display device, when an OFF state of the power supply is detected, a power supply OFF sequence including an initialization step, a first discharge step and a second discharge step is executed. In the initialization step, only a clear signal (H_CLR) among GDM signals is set at a high level, and a state of each of bistable circuits which constitute a shift register is initialized. In the first discharge step, only the clear signal (H_CLR) among the GDM signals is set at a low level, all of gate bus lines are turned to a selected state, and electric charges in pixel formation portions are discharged.
    Type: Grant
    Filed: August 9, 2012
    Date of Patent: April 12, 2016
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akihisa Iwamoto, Hideki Morii, Takayuki Mizunaga, Kazuya Nakaminami, Satoshi Horiuchi
  • Patent number: 9293094
    Abstract: The invention provides a liquid crystal display device that includes an IGZO-GDM which can quickly remove a residual charge in a panel when the power supply is turned off, and a driving method of the liquid crystal display device. Each bistable circuit that configures a shift register includes a thin film transistor TI for increasing a potential of an output terminal based on a first clock, a region netA connected to a gate terminal of the thin film transistor TI, a thin film transistor TC for lowering a potential of the region netA, and a region netB connected to a gate terminal of the thin film transistor TC. In such a configuration, a power supply off sequence includes a display off sequence and a gate off sequence. The gate off sequence includes at least a gate-bus-line discharge step (t14 to t15), a netB discharge step (t15 to t16), and a netA discharge step (t16 to t17).
    Type: Grant
    Filed: August 3, 2012
    Date of Patent: March 22, 2016
    Assignee: SHARP KABUSHIKI KAISHA
    Inventors: Hideki Morii, Akihisa Iwamoto, Satoshi Horiuchi, Takayuki Mizunaga, Kazuya Nakaminami
  • Publication number: 20160037601
    Abstract: A backlight device that achieves high efficiency for a plurality of input voltages includes: a converter circuit; a first light-emitting element column and a second light-emitting element column each including one or more light-emitting elements connected in series; and a group of switches configured to control electrical connection between the converter circuit, the first light-emitting element column and the second light-emitting element column, wherein the group of switches are switched between a plurality of connection states including a first connection state in which the first light-emitting element column and the second light-emitting element column are in series and connected with the converter circuit and a second connection state in which the first light-emitting element column and the second light-emitting element column are in parallel and connected with the converter circuit.
    Type: Application
    Filed: February 19, 2014
    Publication date: February 4, 2016
    Inventors: Xiaomang ZHANG, Toshihiro YANAGI, Takae ITOU, Hideki MORII, Takayuki MIZUNAGA
  • Publication number: 20150319862
    Abstract: The liquid crystal display device includes a liquid crystal panel including a display area for displaying images and a non-display area other than the display area, a rigid board configured to connect with an external signal source, and a flexible board. The liquid crystal panel and the flexible board are arranged in a first direction. A direction perpendicular to the first direction and along a plate surface of the liquid crystal panel is a second direction. The flexible board is larger in a dimension in the second direction than the rigid board, and includes an end portion including at least an outer portion located outside of the rigid board in the second direction, and a middle portion located about a middle of the flexible board with respect to the end portion in the second direction. The end portion is larger in dimension in the first direction than the middle portion.
    Type: Application
    Filed: November 5, 2013
    Publication date: November 5, 2015
    Inventors: Toru KURIYAMA, Hideki MORII, Hirofumi MIYAMOTO, Takayuki MIZUNAGA, Yuta UEYAMA, Toshihiro YANAGI
  • Patent number: 8952880
    Abstract: A display panel drive circuit includes a shift register constructed of unit circuits connected in stages. The unit circuits generate signal line selection signals, respectively, which signal line selection signals are made active for a respective certain period of time to form a respective pulse, and the pulses are outputted successively from respective unit circuits in order of ordinal number starting from a first stage until an end stage. In at least one embodiment, each of the unit circuits receive (i) clock signals generated based on a sync signal received from outside of the display panel drive circuit, (ii) a start pulse signal generated based on the sync signal, or a signal line selection signal generated in a stage different from its own stage, and (iii) a clear signal. The clear signal is made active in a case where anomalousness is included in the sync signal, and no pulse is outputted from the shift register until a subsequent vertical scanning period starts.
    Type: Grant
    Filed: December 17, 2008
    Date of Patent: February 10, 2015
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takayuki Mizunaga, Hideki Morii, Akihisa Iwamoto, Masahiro Hirokane, Yuuki Ohta
  • Publication number: 20150030116
    Abstract: A shift register is configured so that each of first and second intermediate stages includes (i) a first input terminal supplied with a clock signal, (ii) a second input terminal supplied with a clock signal different in phase from the clock signal supplied to the first input terminal, (iii) an output terminal connected to the first input terminal via an output transistor, and (iv) a setting circuit, which is connected to the second input terminal and the output transistor, for setting an electric potential of a control terminal of the output transistor, the second intermediate stage includes a control circuit which is (i) connected to the setting circuit of the second intermediate stage and (ii) supplied with a control signal, an operation period (i) starts at a time when a shift start signal supplied to an initial stage is activated and (ii) ends at a time when an output of a final stage changes from activation to inactivation, and when the clock signal supplied to the first input terminal of the second int
    Type: Application
    Filed: March 5, 2013
    Publication date: January 29, 2015
    Inventors: Satoshi Horiuchi, Shinya Tanaka, Akira Tagawa, Yasuaki Iwase, Takayuki Mizunaga, Akihisa Iwamoto
  • Publication number: 20140306948
    Abstract: Provided are: a liquid crystal display device capable of rapidly removing residual electric charges in a panel when a power supply is turned off, and in particular, suitable for a case where IGZO-GDM is adopted; and a driving method of the liquid crystal display device. In the liquid crystal display device, when an OFF state of the power supply is detected, a power supply OFF sequence including an initialization step, a first discharge step and a second discharge step is executed. In the initialization step, only a clear signal (H_CLR) among GDM signals is set at a high level, and a state of each of bistable circuits which constitute a shift register is initialized. In the first discharge step, only the clear signal (H_CLR) among the GDM signals is set at a low level, all of gate bus lines are turned to a selected state, and electric charges in pixel formation portions are discharged.
    Type: Application
    Filed: August 9, 2012
    Publication date: October 16, 2014
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Akihisa Iwamoto, Hideki Morii, Takayuki Mizunaga, Kazuya Nakaminami, Satoshi Horiuchi
  • Publication number: 20140191935
    Abstract: The invention provides a liquid crystal display device that includes an IGZO-GDM which can quickly remove a residual charge in a panel when the power supply is turned off, and a driving method of the liquid crystal display device. Each bistable circuit that configures a shift register includes a thin film transistor TI for increasing a potential of an output terminal based on a first clock, a region netA connected to a gate terminal of the thin film transistor TI, a thin film transistor TC for lowering a potential of the region netA, and a region netB connected to a gate terminal of the thin film transistor TC. In such a configuration, a power supply off sequence includes a display off sequence and a gate off sequence. The gate off sequence includes at least a gate-bus-line discharge step (t14 to t15), a netB discharge step (t15 to t16), and a netA discharge step (t16 to t17).
    Type: Application
    Filed: August 3, 2012
    Publication date: July 10, 2014
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Hideki Morii, Akihisa Iwamoto, Satoshi Horiuchi, Takayuki Mizunaga, Kazuya Nakaminami
  • Patent number: 8749469
    Abstract: A display device, in at least one embodiment, includes: a gate driver including a plurality of shift register stages each provided so as to correspond to each row, the gate driver outputting a gate signal for turning on switching elements in the each row; and a source driver outputting a data signal in accordance with an image to be displayed. For a row (first row) located at an outermost position from which scanning by use of the gate signal starts, a dummy line is provided. The dummy line is driven by a gate start pulse inputted into a shift register in the first row.
    Type: Grant
    Filed: August 28, 2008
    Date of Patent: June 10, 2014
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akihisa Iwamoto, Hideki Morii, Takayuki Mizunaga, Masahiro Hirokane, Yuuki Ohta
  • Patent number: 8648889
    Abstract: In one embodiment of the present invention, in an even-numbered signal line group, the arrangement sequence of the first and second signal lines is reversed between in a display area and in a non-display area, and the same goes for the arrangement sequence of the third and fourth signal lines. The ends of the first to sixteenth signal lines in the non-display area are connected to the first to sixteenth individual drivers, respectively. An odd-numbered individual driver and an even-numbered individual driver each output a corresponding one of drive signals of opposite polarity. Thus, the polarities of subpixels of the same color arranged in a first direction D1 (horizontal direction) differ between the subpixels connected to the odd-numbered signal line group and the subpixels connected to the even-numbered signal line group. That is, all of the subpixels having the same color arranged in the horizontal direction do not have the same polarity. This helps reduce a horizontal shadow.
    Type: Grant
    Filed: June 28, 2006
    Date of Patent: February 11, 2014
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Yuhko Hisada, Ryohki Itoh, Takaharu Yamada, Hideki Morii, Takayuki Mizunaga
  • Patent number: 8531224
    Abstract: An object is shortening a clock fall-rise period while suppressing an increase in a circuit area, an increase in current consumption, and a cost increase, without generating an abnormal operation, in a shift register within a monolithic gate driver. In a shift register (410) that operates based on four-phase clock signals, including two-phase clock signals (GCK1, GCK3) that are provided to odd-order stages and two-phase clock signals (GCK2, GCK4) that are provided to even-order stages, of which phases are shifted by 90 degrees from each other, a potential of a first clock (CKA) appears as a potential of a scanning signal (GOUT), when a potential of a first node is at a high level, in each stage. In this configuration, the potential of the first node included in each stage is set to a high level based on a pulse of a scanning signal outputted from a pre-stage, and is set to a low level based on a pulse of a scanning signal outputted from a third stage after a stage concerned.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: September 10, 2013
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akihisa Iwamoto, Hideki Morii, Takayuki Mizunaga, Shinya Tanaka, Tetsuo Kikuchi, Takaharu Yamada, Satoshi Horiuchi, Chikao Yamasaki, Kei Ikuta
  • Patent number: 8519764
    Abstract: Each stage that constitutes a shift register includes an output-control thin-film transistor for increasing a potential of a scanning signal based on a first clock (CKA), two thin-film transistors for increasing a potential of a first node connected to a gate terminal of the output-control thin-film transistor, based on a scanning signal outputted from a pre-stage/a latter stage, and two thin-film transistors for decreasing a potential of the first node, based on a scanning signal outputted from a third stage after/a third stage before a stage concerned. The shift register operates based on four-phase clock signals, including two-phase clock signals that are provided to odd-order stages and two-phase clock signals that are provided to even-order stages, of which phases are shifted by 90 degrees from each other.
    Type: Grant
    Filed: July 15, 2010
    Date of Patent: August 27, 2013
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Akihisa Iwamoto, Hideki Morii, Takayuki Mizunaga, Kei Ikuta
  • Publication number: 20130057598
    Abstract: The present invention provides a display panel having decreased cost and current consumption by decreasing the number of data signal lines from the conventional number, a display device including the display panel, and a method of driving the display device. Each pixel formation portion (10) included in a display unit (200) of a display device is configured to arrange three sub-pixel formation portions (1r, 1g, 1b) for forming sub-pixels of mutually different color components in a data signal line extension direction. Each one data signal line (30) is arranged between a sub-pixel formation portion vertical string (3) in an odd-order from a front of a scanning signal line extension direction and a sub-pixel formation portion vertical string (3) adjacent to the sub-pixel formation portion vertical string (3) at the back of the scanning signal line extension direction. Sub-pixel formation portion vertical strings (3, 3) positioned at both sides of each data signal line (30) are connected to the data signal line.
    Type: Application
    Filed: April 18, 2011
    Publication date: March 7, 2013
    Inventors: Akihisa Iwamoto, Hideki Morii, Takayuki Mizunaga, Kei Ikuta
  • Publication number: 20130027104
    Abstract: An object of the present invention is to provide a level shift IC with a reduced number of input signals over the conventional case. A level shift IC includes an amplitude converting unit including four level shifters; and a different-phase signal generating unit at a stage previous to the amplitude converting unit, including delay circuits. The different-phase signal generating unit generates, by the delay circuits, first and second delayed input signals from first and second input signals of different phases. Therefore, four input signals of different phases are obtained, and the amplitude converting unit increases the amplitudes of the input signals by the amplitude converting unit and thereby generates first to fourth output signals with different phases and increased amplitudes.
    Type: Application
    Filed: January 26, 2011
    Publication date: January 31, 2013
    Applicant: SHARP KABUSHIKI KAISHA
    Inventors: Yuuki Ohta, Hideki Morii, Akihisa Iwamoto, Takayuki Mizunaga