Patents by Inventor Katsuhiko Kumagawa

Katsuhiko Kumagawa 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: 9117778
    Abstract: A display device includes: a display panel including a plurality of pixels arranged in rows and columns; and a touch panel opposed to the display panel, wherein the display panel includes a non-display portion which is a region between neighboring pixels, the touch panel includes: a plurality of first electrode patterns which are formed along a first direction which is one of a row direction and a column direction of the pixels; and a plurality of second electrode patterns which are formed along a second direction which is the other one of the directions, at least a part of the first electrode patterns and at least a part of the second electrode patterns being metal, and the metal parts of the first electrode patterns and the second electrode patterns are present within the non-display portion of the display panel in plan view.
    Type: Grant
    Filed: July 18, 2012
    Date of Patent: August 25, 2015
    Assignee: Joled Inc.
    Inventors: Hiroto Yanagawa, Katsuhiko Kumagawa
  • Publication number: 20140139761
    Abstract: A display device includes: a display panel including a plurality of pixels arranged in rows and columns; and a touch panel opposed to the display panel, wherein the display panel includes a non-display portion which is a region between neighboring pixels, the touch panel includes: a plurality of first electrode patterns which are formed along a first direction which is one of a row direction and a column direction of the pixels; and a plurality of second electrode patterns which are formed along a second direction which is the other one of the directions, at least a part of the first electrode patterns and at least a part of the second electrode patterns being metal, and the metal parts of the first electrode patterns and the second electrode patterns are present within the non-display portion of the display panel in plan view.
    Type: Application
    Filed: July 18, 2012
    Publication date: May 22, 2014
    Applicant: PANASONIC CORPORATION
    Inventors: Hiroto Yanagawa, Katsuhiko Kumagawa
  • Publication number: 20110007050
    Abstract: When displaying moving images by using liquid crystal panels and others, a problem exists in that tail streaks occur, and image degradation is resultantly caused. To solve this problem, an echo suppression circuit divides a video signal into a pair composed of two successive frames for comparison between these two frames in signal level for the purpose of suppressing an echo phenomenon occurring when a liquid crystal panel displays video signals including moving images. If these two frames are not the same in signal level, the signal is accordingly corrected so as to equalize the signal level of these frames. Based on the video signals and others corrected by the echo suppression circuit, a controller operates the liquid crystal panel with AC drive through a source driver and a gate driver. As such, the drive voltage used to operate the liquid crystal panel with AC drive is adjusted so as to be balanced between positive and negative.
    Type: Application
    Filed: September 8, 2010
    Publication date: January 13, 2011
    Inventors: Ichiro SATO, Katsuhiko KUMAGAWA, Kazuo INOUE, Taro FUNAMOTO, Wataru MACHIDORI, Katsuyuki ARIMOTO
  • Publication number: 20090174828
    Abstract: An array substrate (10) is provided with a pixel electrode (3) disposed in a region defined by two adjacent gate wirings (1) and two adjacent source wirings (2), a switching element (5) for switching a voltage applied to the pixel electrode (3) from the source wiring (2) based on a signal voltage supplied from the gate wiring (1), a common wiring (8) arranged between the two adjacent gate wirings (1) and a common electrode (4) being electrically connected to the common wiring (8) and generating an electric field between the pixel electrode (3) whereto a voltage is applied, wherein the pixel electrode (1) comprises a first pixel electrode (1a) and a second pixel electrode (2a), and the opposing electrode (2) comprises a first opposing electrode (1b) and a second opposing electrode (2b), wherein a first region generates an electric field between the first pixel electrode (1a) and the first opposing electrode (2a) whose light transmittance is lower than that of the first pixel electrode (1a) and a second region
    Type: Application
    Filed: February 2, 2009
    Publication date: July 9, 2009
    Applicant: PANASONIC CORPORATION
    Inventors: Katsuhiko KUMAGAWA, Hiroyuki Yamakita, Masanori Kimura, Akio Takimoto
  • Patent number: 7499115
    Abstract: An array substrate (10) is provided with a pixel electrode (3) disposed in a region defined by two adjacent gate wirings (1) and two adjacent source wirings (2), a switching element (5) for switching a voltage applied to the pixel electrode (3) from the source wiring (2) based on a signal voltage supplied from the gate wiring (1), a common wiring (8) arranged between the two adjacent gate wirings (1) and a common electrode (4) being electrically connected to the common wiring (8) and generating an electric field between the pixel electrode (3) whereto a voltage is applied, wherein the pixel electrode (1) comprises a first pixel electrode (1a) and a second pixel electrode (2a), and the opposing electrode (2) comprises a first opposing electrode (1b) and a second opposing electrode (2b), wherein a first region generates an electric field between the first pixel electrode (1a) and the first opposing electrode (2a) whose light transmittance is lower than that of the first pixel electrode (1a) and a second region
    Type: Grant
    Filed: October 4, 2001
    Date of Patent: March 3, 2009
    Assignee: Panasonic Corporation
    Inventors: Katsuhiko Kumagawa, Hiroyuki Yamakita, Masanori Kimura, Akio Takimoto
  • Patent number: 7215476
    Abstract: Laser beams respectively emitted from a SHG blue laser unit and a red semiconductor laser unit that have photo detectors respectively are turned into parallel lights by a collimator lens and then coupled by a dielectric multi-layer film mirror so as to be propagated on the same optical axis. The dielectric multi-layer film mirror is configured so as to transmit light with a wavelength of 500 nm or shorter and reflect light with a wavelength of 500 nm or longer for both P wave and S wave. The lights that are transmitted and reflected by the dielectric multi-layer film mirror pass through a polarizing hologram and a phase variable wave plate and are focused on an optical disk by an objective lens. In this manner, a simple configuration can realize a compatibility with many types of optical disks and a stable signal detection even when using a polarizing optical detection system.
    Type: Grant
    Filed: October 27, 2004
    Date of Patent: May 8, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuo Kitaoka, Ken'ichi Kasazumi, Katsuhiko Kumagawa, Kazuhisa Yamamoto, Hidenori Wada
  • Publication number: 20070063944
    Abstract: When displaying moving images by using liquid crystal panels and others, a problem exists in that tail streaks occur, and image degradation is resultantly caused. To solve this problem, an echo suppression circuit divides a video signal into a pair composed of two successive frames for comparison between these two frames in signal level for the purpose of suppressing an echo phenomenon occurring when a liquid crystal panel displays video signals including moving images. If these two frames are not the same in signal level, the signal is accordingly corrected so as to equalize the signal level of these frames. Based on the video signals and others corrected by the echo suppression circuit, a controller operates the liquid crystal panel with AC drive through a source driver and a gate driver. As such, the drive voltage used to operate the liquid crystal panel with AC drive is adjusted so as to be balanced between positive and negative.
    Type: Application
    Filed: November 28, 2006
    Publication date: March 22, 2007
    Inventors: Ichiro Sato, Katsuhiko Kumagawa, Kazuo Inoue, Taro Funamoto, Wataru Machidori, Katsuyuki Arimoto
  • Patent number: 7173609
    Abstract: When displaying moving images by using liquid crystal panels and others, a problem exists in that tail streaks occur, and image degradation is resultantly caused. To solve this problem, an echo suppression circuit divides a video signal into a pair composed of two successive frames for comparison between these two frames in signal level for the purpose of suppressing an echo phenomenon occurring when a liquid crystal panel displays video signals including moving images. If these two frames are not the same in signal level, the signal is accordingly corrected so as to equalize the signal level of these frames. Based on the video signals and others corrected by the echo suppression circuit, a controller operates the liquid crystal panel with AC drive through a source driver and a gate driver. As such, the drive voltage used to operate the liquid crystal panel with AC drive is adjusted so as to be balanced between positive and negative.
    Type: Grant
    Filed: June 8, 2001
    Date of Patent: February 6, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ichiro Sato, Katsuhiko Kumagawa, Kazuo Inoue, Taro Funamoto, Wataru Machidori, Katsuyuki Arimoto
  • Patent number: 7161574
    Abstract: A liquid crystal display element driving method or a liquid crystal display device uses a liquid crystal display element having a plurality of pixels constituting a screen; divides a frame period into a plurality of write periods and outputs gate signals to select the pixels sequentially during the write periods; forms each of source signals such that the source signal includes a picture signal and a non-picture signal respectively assigned for the write periods; writes each of the source signals corresponding to the selected pixels to each of the pixels with its polarity being alternated; and displays an image responsive to the source signals on the screen of the liquid crystal display element in such a manner that a transmittivity of liquid crystals of each of the pixels is controlled in accordance with the written source signal, wherein the non-picture signal having a polarity identical to that of the picture signal to be written subsequently is written to the pixels.
    Type: Grant
    Filed: May 30, 2002
    Date of Patent: January 9, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masanori Kimura, Ichiro Sato, Katsuhiko Kumagawa
  • Publication number: 20060119566
    Abstract: Disclosed is a liquid crystal display capable of ensuring brightness necessary for achieving satisfactory display by increasing ratio of light-emitting time to one frame period. A liquid crystal display is adapted to have a period (non-video signal write period) required for writing non-video signals different from video signals onto all the pixels before a video signal write period. In the non-video signal write period, the non-video signals are written onto the respective pixels, thereby starting response of the liquid crystal before the start of the video signal write period. In the non-video signal write period, a backlight is turned off, and thereby image degradation is prevented even when the non-video signals are written onto the respective pixels.
    Type: Application
    Filed: January 18, 2006
    Publication date: June 8, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Ichiro Sato, Katsuhiko Kumagawa, Hiroyuki Yamakita, Kazunori Komori
  • Publication number: 20060114204
    Abstract: Disclosed is a liquid crystal display capable of ensuring brightness necessary for achieving satisfactory display by increasing ratio of light-emitting time to one frame period. A liquid crystal display is adapted to have a period (non-video signal write period) required for writing non-video signals different from video signals onto all the pixels before a video signal write period. In the non-video signal write period, the non-video signals are written onto the respective pixels, thereby starting response of the liquid crystal before the start of the video signal write period. In the non-video signal write period, a backlight is turned off, and thereby image degradation is prevented even when the non-video signals are written onto the respective pixels.
    Type: Application
    Filed: January 18, 2006
    Publication date: June 1, 2006
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Ichiro Sato, Katsuhiko Kumagawa, Hiroyuki Yamakita, Kazunori Komori
  • Patent number: 7035192
    Abstract: Laser beams respectively emitted from a SHG blue laser unit and a red semiconductor laser unit that have photo detectors respectively are turned into parallel lights by a collimator lens and then coupled by a dielectric multi-layer film mirror so as to be propagated on the same optical axis. The dielectric multi-layer film mirror is configured so as to transmit light with a wavelength of 500 nm or shorter and reflect light with a wavelength of 500 nm or longer for both P wave and S wave. The lights that are transmitted and reflected by the dielectric multi-layer film mirror pass through a polarizing hologram and a phase variable wave plate and are focused on an optical disk by an objective lens. In this manner, a simple configuration can realize a compatibility with many types of optical disks and a stable signal detection even when using a polarizing optical detection system.
    Type: Grant
    Filed: June 22, 2004
    Date of Patent: April 25, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuo Kitaoka, Ken'ichi Kasazumi, Katsuhiko Kumagawa, Kazuhisa Yamamoto, Hidenori Wada
  • Patent number: 7034790
    Abstract: A method of driving a liquid crystal display and the liquid crystal display of the present invention are such that in a liquid crystal display in which video signals are written onto a plurality of pixels frame by frame (Tf), voltages corresponding to the video signals are held in the pixels, and a modulation degree of the liquid crystal layer in an alignment state for display is controlled in accordance with the held voltages, thereby displaying an image, a backward-transition-prevention voltage ?V for preventing backward transition of a liquid crystal layer is temporalily superposed on the voltages (Vd1–Vdn) corresponding to the video signals in a hold period (Th) of the voltages (Vd1–Vdn) corresponding to the video signals.
    Type: Grant
    Filed: October 24, 2001
    Date of Patent: April 25, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tetsuo Fukami, Katsuhiko Kumagawa, Kenji Nakao
  • Patent number: 7030848
    Abstract: Disclosed is a liquid crystal display capable of ensuring brightness necessary for achieving satisfactory display by increasing ratio of light-emitting time to one frame period. A liquid crystal display is adapted to have a period (non-video signal write period) required for writing non-video signals different from video signals onto all the pixels before a video signal write period. In the non-video signal write period, the non-video signals are written onto the respective pixels, thereby starting response of the liquid crystal before the start of the video signal write period. In the non-video signal write period, a backlight is turned off, and thereby image degradation is prevented even when the non-video signals are written onto the respective pixels.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: April 18, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Ichiro Sato, Katsuhiko Kumagawa, Hiroyuki Yamakita, Kazunori Komori
  • Patent number: 6965367
    Abstract: Disclosed is a display capable of improving uniformity of luminance and chroma in a plane of a display panel. When point at which the light source is turned ON is represented by T1, transmittance in a display region onto which the video signals are being written at the point T1 is represented by M1, point at which the light source is turned OFF is represented by T2, transmittance in the display region onto which the video signals are being written at point T2 is represented by M2, a maximum value of the transmittance in the display region of the light modulation element in a period during which the light source is ON is represented by M0, and the write period is represented by Twrite, the illuminating device control portion is adapted to control the illuminating device so as to satisfy a formula given by [|M2?M1|Twrite]/[M0(T2?T1)]?0.92.
    Type: Grant
    Filed: March 28, 2002
    Date of Patent: November 15, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yukio Tanaka, Masanori Kimura, Takashi Okada, Katsuhiko Kumagawa
  • Patent number: 6963335
    Abstract: An active matrix type display apparatus is provided that is inexpensive, has less crosstalk, has no flickering and a brightness gradient, and is suitable for a large screen size. The display apparatus includes a plurality of pixel electrodes arranged in a matrix, switching elements (TFTs) connected thereto, scanning electrodes, video signal electrodes, common electrodes, and a counter electrode, wherein liquid crystal, for example, is interposed between the pixel electrodes and the counter electrode. Assuming that a gate-drain capacitance is Cgd, a common electrode-pixel electrode capacitance is Cst, and the total capacitance connected to the pixel electrodes is Ctot in this configuration, ?gd and ?st represented by ?gd=Cgd/Ctot, ?st=Cst/Ctot are set to be different values between a portion close to feeding ends in a screen and a portion away therefrom.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: November 8, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yukio Tanaka, Katsuhiko Kumagawa, Masanori Kimura, Kazunori Komori
  • Patent number: 6933916
    Abstract: A liquid crystal display of the present invention is adapted to perform initialization by inputting voltages with different polarities to two pixel electrodes (23á, 23â) adjacent in front and back direction. It is preferable that in the two pixel electrodes (23á, 23â) adjacent in front and back direction, the pixel electrode (23á) located on back side is provided with a first protrusion (232á) at a front side and back direction, the pixel electrode (231â) adjacent in front and back is provided with a second protrusion (23â) located on front side is provided with a second a second protrusion (234â) on a back side edge (233â)thereof.
    Type: Grant
    Filed: December 18, 2001
    Date of Patent: August 23, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kenji Nakao, Daiichi Suzuki, Yoshinori Kobayashi, Katsuyuki Arimoto, Katsuhiko Kumagawa, Ichiro Sato, Keisuke Tsuda, Hirofumi Wakemoto, Hiroyuki Yamakita, Masanori Kimura, Yoshinori Tanaka, Akinori Shiota
  • Patent number: 6914644
    Abstract: In a liquid crystal panel in which pseudo dot inversion driving is performed, the occurrence of flicker or vertical and horizontal strings is prevented by preventing an alignment shift between individual layers during the fabrication of a TFT array from producing a difference between the respective abilities of thin-film TFTs to charge adjacent pixels (61, 62). For this purpose, the liquid crystal display panel is constructed such that two TFTs which are enclosed by two adjacent image signal lines (21, 22) and scan signal lines (3) and adjacent to each other along the signal lines (21, 22) have respective source electrodes (71, 72) adjacent to the different image signal lines (21, 22). The source electrodes (71, 72) and drain electrodes (81, 82) of the two TFTs connected to the adjacent pixels (61, 62) are alternately arranged such that variations caused by the alignment shift in the sizes and areas of overlapping portions between the individual layers of the TFTs are equal or the same.
    Type: Grant
    Filed: December 20, 2000
    Date of Patent: July 5, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tetsuo Fukami, Katsuhiko Kumagawa, Masanori Kimura, Satoshi Asada, Yoneharu Takubo
  • Patent number: 6909415
    Abstract: The present invention provides a display apparatus that can reduce a voltage irregularity and a brightness irregularity accompanied by making an enlarged and a high resolution type display apparatus.
    Type: Grant
    Filed: April 23, 2001
    Date of Patent: June 21, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Katsuhiko Kumagawa, Masanori Kimura, Tetsuo Fukami, Akio Takimoto, Yukio Tanaka, Kazunori Komori
  • Patent number: RE41237
    Abstract: An active matrix type display apparatus is provided that is inexpensive, has less crosstalk, has no flickering and a brightness gradient, and is suitable for a large screen size. The display apparatus includes a plurality of pixel electrodes arranged in a matrix, switching elements (TFTs) connected thereto, scanning electrodes, video signal electrodes, common electrodes, and a counter electrode, wherein liquid crystal, for example, is interposed between the pixel electrodes and the counter electrode. Assuming that a gate-drain capacitance is Cgd, a common electrode-pixel electrode capacitance is Cst, and the total capacitance connected to the pixel electrodes is Ctot in this configuration, ?gd and ?st represented by ?gd=Cgd/Ctot, ?st=Cst/Ctot are set to be different values between a portion close to feeding ends in a screen and a portion away therefrom.
    Type: Grant
    Filed: June 11, 2001
    Date of Patent: April 20, 2010
    Assignee: Panasonic Corporation
    Inventors: Yukio Tanaka, Katsuhiko Kumagawa, Masanori Kimura, Kazunori Komori