Patents by Inventor Kazuo Yahagi

Kazuo Yahagi 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: 8421713
    Abstract: It is an object to provide a driving method of a plasma display panel, whereby a dark contrast can be improved while suppressing an erroneous discharge. In a resetting step in a first unit display period, while a first reset pulse having a predetermined peak electric potential is applied to one of first row electrodes of row electrode pairs formed in the PDP, a second reset pulse having a peak electric potential smaller than that of the first reset pulse is applied to the other of the first row electrodes. In the resetting step in a second unit display period subsequent to the first unit display period, a second reset pulse is applied to each of the one and the other of the first row electrodes.
    Type: Grant
    Filed: April 17, 2012
    Date of Patent: April 16, 2013
    Assignee: Panasonic Corporation
    Inventors: Kazuo Yahagi, Mitsuhiro Ishizuka, Yuya Shiozaki, Shunsuke Itakura, Kazuhiro Kanai, Hajime Homma, Yoshichika Sato, Hikaru Takahashi
  • Patent number: 8269694
    Abstract: A method for driving a plasma display panel (PDP) that can increase dark contrast without causing erroneous discharges is provided. A unit display period is divided into a plurality of subfields. A reset process and a sustain process are performed in one of the subfields. In the reset process, a reset pulse is applied to row electrodes of the PDP to initialize each discharge cell to an emission mode (or non-emission mode). In the sustain process, a sustain discharge is repeatedly generated a number of times, corresponding to the number of times a sustain pulse is to be applied, in those discharge cells that are in the emission mode. In this case, a peak potential of the reset pulse is changed based on the number of those discharge cells that are maintained in the non-emission mode during the unit display period and the number of times the sustain pulse is to be applied in the sustain process in this subfield.
    Type: Grant
    Filed: September 10, 2008
    Date of Patent: September 18, 2012
    Assignee: Panasonic Corporation
    Inventors: Yuya Shiozaki, Hitoshi Fujimura, Kazuo Yahagi, Tsutomu Tokunaga
  • Publication number: 20120200543
    Abstract: It is an object to provide a driving method of a plasma display panel, whereby a dark contrast can be improved while suppressing an erroneous discharge. In a resetting step in a first unit display period, while a first reset pulse having a predetermined peak electric potential is applied to one of first row electrodes of row electrode pairs formed in the PDP, a second reset pulse having a peak electric potential smaller than that of the first reset pulse is applied to the other of the first row electrodes. In the resetting step in a second unit display period subsequent to the first unit display period, a second reset pulse is applied to each of the one and the other of the first row electrodes.
    Type: Application
    Filed: April 17, 2012
    Publication date: August 9, 2012
    Applicant: PANASONIC CORPORATION
    Inventors: Kazuo YAHAGI, Mitsuhiro ISHIZUKA, Yuya SHIOZAKI, Shunsuke ITAKURA, Kazuhiro KANAI, Hajime HOMMA, Yoshichika SATO, Hikaru TAKAHASHI
  • Patent number: 8203507
    Abstract: A drive method of a plasma display panel that can increase the dark contrast, without causing a discharge failure. When a discharge cell that assumes a black display state in a first field from among first and a second fields that are adjacent in time and switches to a display state representing a brightness other than black in the second field is detected as a lighting transition cell, at least one drive of the below-described first and second forced lighting drives is executed. In the first forced lighting drive, the lighting transition cell is forcibly set into the lighting mode only in the address process of a predetermined subfield within the field in the first field. In the second forced lighting drive, an adjacent discharge cell that is adjacent to the lighting transition cell is forcibly set into the lighting mode only in the address process of the predetermined subfield in the second field.
    Type: Grant
    Filed: February 29, 2008
    Date of Patent: June 19, 2012
    Assignee: Panasonic Corporation
    Inventors: Shunsuke Itakura, Mitsuhiro Ishizuka, Kazuo Yahagi, Tetsuya Shigeta, Hirofumi Honda
  • Publication number: 20090267974
    Abstract: A plasma display device and a method for driving a Plasma Display Panel (PDP), which can reduce power consumption without causing display malfunction or reducing image quality, are provided. When the input of an image signal is stopped or when an input image signal is in an entirely-black image state, the application of a drive pulse for driving the PDP is stopped. Here, when the input of the image signal is resumed or when the input image signal switches from the entirely-black image state to a normal image state, the absolute value of a peak potential of the drive pulse or the pulse width thereof is increased to increase the strength of discharge until a predetermined period elapses after the resumption or switching and then the absolute value of a peak potential of the drive pulse or the pulse width is returned to a normal absolute value or a normal pulse width.
    Type: Application
    Filed: August 18, 2008
    Publication date: October 29, 2009
    Applicant: PIONEER CORPORATION
    Inventors: Mitsushi Kitagawa, Mitsuhiro Ishizuka, Kazuo Yahagi
  • Publication number: 20090231237
    Abstract: A method for driving a plasma display panel (PDP) that can increase dark contrast without causing erroneous discharges is provided. A unit display period is divided into a plurality of subfields. A reset process and a sustain process are performed in one of the subfields. In the reset process, a reset pulse is applied to row electrodes of the PDP to initialize each discharge cell to an emission mode (or non-emission mode). In the sustain process, a sustain discharge is repeatedly generated a number of times, corresponding to the number of times a sustain pulse is to be applied, in those discharge cells that are in the emission mode. In this case, a peak potential of the reset pulse is changed based on the number of those discharge cells that are maintained in the non-emission mode during the unit display period and the number of times the sustain pulse is to be applied in the sustain process in this subfield.
    Type: Application
    Filed: September 10, 2008
    Publication date: September 17, 2009
    Applicant: PIONEER CORPORATION
    Inventors: Yuya SHIOZAKI, Hitoshi Fujimura, Kazuo Yahagi, Tsutomu Tokunaga
  • Publication number: 20090219226
    Abstract: It is an object to provide a driving method of a plasma display panel, whereby a dark contrast can be improved while suppressing an erroneous discharge. In a resetting step in a first unit display period, while a first reset pulse having a predetermined peak electric potential is applied to one of first row electrodes of row electrode pairs formed in the PDP, a second reset pulse having a peak electric potential smaller than that of the first reset pulse is applied to the other of the first row electrodes. In the resetting step in a second unit display period subsequent to the first unit display period, a second reset pulse is applied to each of the one and the other of the first row electrodes.
    Type: Application
    Filed: August 7, 2008
    Publication date: September 3, 2009
    Applicant: PIONEER CORPORATION
    Inventors: Kazuo Yahagi, Mitsuhiro Ishizuka, Yuya Shiozaki, Shunsuke Itakura, Kazuhiro Kanai, Hajime Homma, Yoshichika Sato, Hikaru Takahashi
  • Publication number: 20080211741
    Abstract: A drive method of a plasma display panel that can increase the dark contrast, without causing a discharge failure. When a discharge cell that assumes a black display state in a first field from among first and a second fields that are adjacent in time and switches to a display state representing a brightness other than black in the second field is detected as a lighting transition cell, at least one drive of the below-described first and second forced lighting drives is executed. In the first forced lighting drive, the lighting transition cell is forcibly set into the lighting mode only in the address process of a predetermined subfield within the field in the first field. In the second forced lighting drive, an adjacent discharge cell that is adjacent to the lighting transition cell is forcibly set into the lighting mode only in the address process of the predetermined subfield in the second field.
    Type: Application
    Filed: February 29, 2008
    Publication date: September 4, 2008
    Applicant: PIONEER CORPORATION
    Inventors: Shunsuke ITAKURA, Mitsuhiro ISHIZUKA, Kazuo YAHAGI, Tetsuya SHIGETA, Hirofumi HONDA
  • Patent number: 7391392
    Abstract: Only when an input image signal continues to indicate a black display for a predetermined period of time or longer, some pixel cells randomly selected from among all pixel cells on a display screen are forcibly set to a light-emitting mode in an address process of a subfield with a small weighting.
    Type: Grant
    Filed: March 7, 2005
    Date of Patent: June 24, 2008
    Assignee: Pioneer Corporation
    Inventor: Kazuo Yahagi
  • Publication number: 20080074354
    Abstract: A plasma display apparatus in which in an address period, address discharge is generated in each display cell of a display panel selectively in accordance with pixel data based on a video signal, and in a sustain period, a sustain pulse for sustain discharge is applied between row electrodes constituting the row electrode pairs by a predetermined number of times which is preset for each of the subfields, and a length of a front-edge period of the sustain pulse to be applied is adjusted subfield by subfield in accordance with a load level in each subfield.
    Type: Application
    Filed: September 11, 2007
    Publication date: March 27, 2008
    Inventors: Kazuo Yahagi, Mitsunori Taguchi, Kazuhiro Kanai, Yuichi Sakai, Mitsushi Kitagawa, Yoshichika Sato, Takatoshi Shoji, Motofumi Ikeda
  • Patent number: 7176856
    Abstract: The present invention is a display device and display panel drive method that allow a more rapid select operation to be stably implemented by increasing the discharge probability of selective discharge. The display device comprises an address part that sequentially applies a positive scan pulse to a first row electrode of each of the display panel row electrode pairs in the address cycle while sequentially applying a pixel data pulse corresponding to the pixel data at the same timing as the scan pulse to each of the display panel column electrodes one display line at a time so that the column electrode side constitutes a cathode, such that an address discharge is selectively produced in the second discharge cell; and a sustain part that applies a sustain pulse to each of the row electrodes constituting the row electrode pairs in the sustain cycle, and the sustain part applies the ultimate sustain pulse of the sustain pulses applied in the address cycle to the first row electrode with a negative polarity.
    Type: Grant
    Filed: December 24, 2003
    Date of Patent: February 13, 2007
    Assignee: Pioneer Corporation
    Inventors: Kazuo Yahagi, Tsutomu Tokunaga, Yuya Shiozaki, Shigeru Iwaoka
  • Patent number: 7136034
    Abstract: A display panel includes a plurality of unit light emission areas (light emission elements) arranged in a matrix. Each unit light emission area is defined by a first discharge cell and a second discharge cell. The second discharge cell has a light-absorbing layer. When the display panel is driven to express an image having a plurality of gradation levels, address discharge is selectively caused in the second discharge cells in accordance with an input image signal. Light leaks to the first discharge cell from the second discharge cell upon the address discharge. This light is used to express the gradation of low luminance. Since luminance difference between gradation levels of a low luminance image is reduced, it is possible to display a high quality, low luminance image.
    Type: Grant
    Filed: October 6, 2003
    Date of Patent: November 14, 2006
    Assignees: Pioneer Corporation, Pioneer Display Products Corporation
    Inventors: Tsutomu Tokunaga, Nobuhiko Saegusa, Kazuo Yahagi, Mitsushi Kitagawa, Shigeru Iwaoka
  • Patent number: 7091668
    Abstract: A display and a driving method of a display panel capable of improving a dark contrast.
    Type: Grant
    Filed: October 3, 2003
    Date of Patent: August 15, 2006
    Assignees: Pioneer Corporation, Pioneer Display Products Corporation
    Inventors: Kazuo Yahagi, Mitsushi Kitagawa, Nobuhiko Saegusa, Shigeru Iwaoka, Tsutomu Tokunaga, Ryo Suzue
  • Patent number: 7075504
    Abstract: A plasma display panel capable of improving dark contrast. A unit light emission region is comprised of a display discharge cell in which a discharge is produced between portions of row electrodes X, Y of each row electrode pair (X, Y) opposing each other, and a reset and address discharge cell arranged in parallel with the display discharge cell, in which a discharge is produced between portions of the row electrode Y and a row electrode X of another adjacent row electrode pair (X, Y). The display discharge cell and reset and address discharge cell are communicated with each other. A light absorbing layer is formed in a portion of the reset and address discharge cell opposing the display surface. According to another aspect, the unit light emission region in the display panel comprises a first discharge cell and a second discharge cell comprising a light absorbing layer.
    Type: Grant
    Filed: September 13, 2002
    Date of Patent: July 11, 2006
    Assignees: Pioneer Corporation, Pioneer Display Products Corporation
    Inventors: Tsutomu Tokunaga, Nobuhiko Saegusa, Kazuo Yahagi, Mitsushi Kitagawa, Ryo Suzue, Eishiro Otani, Yoichi Sato
  • Publication number: 20050195133
    Abstract: Only when an input image signal continues to indicate a black display for a predetermined period of time or longer, some pixel cells randomly selected from among all pixel cells on a display screen are forcibly set to a light-emitting mode in an address process of a subfield with a small weighting.
    Type: Application
    Filed: March 7, 2005
    Publication date: September 8, 2005
    Inventor: Kazuo Yahagi
  • Publication number: 20050083256
    Abstract: In each of a plurality of sub-fields forming a field, in order to cause continuous luminescence of the pixel, at least one of the sustain pulses to be applied in the later section in a sustain period for which sustain pulses are to be repeatedly applied has a pulse voltage amplitude given greater than a pulse voltage amplitude of the other sustain pulse.
    Type: Application
    Filed: October 7, 2004
    Publication date: April 21, 2005
    Inventors: Kazuo Yahagi, Yuya Shiozaki
  • Publication number: 20050073479
    Abstract: A display apparatus which sequentially applies a scanning pulse to one row electrode of the row electrode pair while applying a pixel data pulse corresponding to the pixel data to the column electrodes one display line by one display line, simultaneously with the scanning pulse, to selectively produce an address discharge in the second discharge cell in the address period, applies a sustain pulse to the row electrode pairs in the sustain period, and produces a reset discharge in the same discharge current direction as the address discharge between one row electrode of the row electrode pair and the column electrode in the second discharge cell immediately before the address period of at least the first sub-field of the one-field display period, and a method of driving the display panel.
    Type: Application
    Filed: September 30, 2004
    Publication date: April 7, 2005
    Inventors: Hikaru Takahashi, Hideto Endo, Keishi Saito, Kazuo Yahagi, Yuya Shiozaki, Yuichi Sakai, Shigeru Iwaoka, Nobuhiko Saegusa
  • Publication number: 20050068264
    Abstract: It is an object to provide a display device capable of simplifying the interconnection between a display panel and a driver for driving the display panel. A plurality of connection terminals for connection to display electrodes arranged at odd-number-th positions of the display panel is provided at one end in the row direction on a front substrate of the display panel. A plurality of connection terminals for connection to display electrodes arranged at even-number-th positions of the display panel is provided at the other end in a row direction on the front substrate. On the front substrate is mounted a driver for applying a drive pulse to the display electrode arranged at odd-number-th positions through the respective connection terminals provided at one end in a row direction on the front substrate.
    Type: Application
    Filed: September 23, 2004
    Publication date: March 31, 2005
    Inventor: Kazuo Yahagi
  • Publication number: 20040179004
    Abstract: The present invention is a display device and display panel drive method that allow a more rapid select operation to be stably implemented by increasing the discharge probability of selective discharge. The display device comprises an address part that sequentially applies a positive scan pulse to a first row electrode of each of the display panel row electrode pairs in the address cycle while sequentially applying a pixel data pulse corresponding to the pixel data at the same timing as the scan pulse to each of the display panel column electrodes one display line at a time so that the column electrode side constitutes a cathode, such that an address discharge is selectively produced in the second discharge cell; and a sustain part that applies a sustain pulse to each of the row electrodes constituting the row electrode pairs in the sustain cycle, and the sustain part applies the ultimate sustain pulse of the sustain pulses applied in the address cycle to the first row electrode with a negative polarity.
    Type: Application
    Filed: December 24, 2003
    Publication date: September 16, 2004
    Applicant: PIONEER CORPORATION
    Inventors: Kazuo Yahagi, Tsutomu Tokunaga, Yuya Shiozaki, Shigeru Iwaoka
  • Publication number: 20040164932
    Abstract: A plasma display panel includes a front substrate and a rear substrate, with a discharge space therebetween. Row and column electrodes extend on an inner surface of the front substrate. Each display line is defined by paired two adjacent row electrodes. A dielectric layer covers the row electrodes. Unit light-emission areas are formed in the discharge space at intersections of the row and column electrodes. A partition wall matrix comparts the unit light-emission areas from each other. A separation wall divides each unit light-emission area into a first discharge cell, in which discharge occurs across the paired two adjacent row electrodes associated with that unit light-emission area, and a second discharge cell, in which discharge occurs across one of the paired two adjacent row electrodes and the column electrode concerned. The first discharge cell communicates with the second discharge cell via a passage in each unit light-emission area.
    Type: Application
    Filed: February 24, 2004
    Publication date: August 26, 2004
    Applicant: PIONEER CORPORATION
    Inventors: Eishiro Otani, Kazuo Yahagi