Patents by Inventor Hidehiko Shoji

Hidehiko Shoji 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: 20100066727
    Abstract: A scan electrode driving circuit applies a rising ramp waveform voltage to scan electrodes (SCN1 to SCNn) to generate a first setup discharge in a first period within a setup period, applies a dropping ramp waveform voltage to the scan electrodes (SCN1 to SCNn) to generate a second setup discharge in a second period following the first period within the setup period, and applies a positive rectangular waveform voltage (Va) and a negative rectangular waveform voltage (Va) to the scan electrodes (SCN1 to SCNn) in a third period following the second period within the setup period. A data electrode driving circuit applies a positive rectangular waveform voltage (Vd) to data electrodes (D1 to Dm) in a period after application of the positive rectangular waveform voltage (Vs) to the scan electrodes (SCN to SCNn) and before application of the negative rectangular waveform voltage (Va) to the scan electrodes (SCN1 to SCNn) in the third period.
    Type: Application
    Filed: December 6, 2007
    Publication date: March 18, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Toshiyuki Maeda, Hidehiko Shoji
  • Publication number: 20100060627
    Abstract: A scan electrode driving circuit applies a first ramp waveform rising from a first potential (Vi1) to a second potential (Vi2) to a plurality of scan electrodes (SC) in a first half period within a setup period of at least one sub-field of a plurality of sub-fields, and applies a second ramp waveform dropping from a third potential (Vi3) to a fourth potential (Vi4) to the plurality of scan electrodes (SC) in a second half period following the first half period. A sustain electrode driving circuit applies a third ramp waveform rising from a fifth potential (ground potential) to a sixth potential (Vi5) to a plurality of sustain electrodes (SU) in a period, which is shorter than the first half period, within the first half period, and applies a fourth ramp waveform dropping from a seventh potential (Ve) to an eighth potential (Vi6) to the plurality of sustain electrodes (SC) in a period, which is shorter than the second half period, within the second half period.
    Type: Application
    Filed: November 28, 2007
    Publication date: March 11, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Takahiko Origuchi, Hidehiko Shoji
  • Publication number: 20100039417
    Abstract: A scan electrode driving circuit applies a rising ramp waveform voltage to scan electrodes (SCN1 to SCNn) to generate a first setup discharge in a first period within a setup period, applies a dropping ramp waveform voltage to the scan electrodes (SCN1 to SCNn) to generate a second setup discharge in a second period following the first period within the setup period, and applies a first positive rectangular waveform voltage (Vs), a negative rectangular waveform voltage (Va), a second positive rectangular waveform voltage (Vs) and a dropping ramp waveform voltage to the scan electrodes (SCN1 to SCNn) in a third period following the second period within the setup period.
    Type: Application
    Filed: December 7, 2007
    Publication date: February 18, 2010
    Applicant: PANASONIC CORPORATION
    Inventors: Toshiyuki Maeda, Hidehiko Shoji
  • Publication number: 20100033459
    Abstract: A stable address discharge is generated and number of unlit cells is decreased without heightening the voltage necessary for generating an address discharge. For this purpose, the device includes a plasma display panel and a driving circuit for driving the plasma display panel, in which the driving circuit drives the plasma display panel having a sub-field group formed of two or more continuous sub-fields for controlling addressing provided in one field period, so as not to generate sustain discharge in the discharge cell not causing sustain discharge and also in the subsequent sub-fields, the discharge cell is initialized by applying a ramp waveform voltage descending gently to the scan electrode, the lowest voltage of the ramp waveform voltage of the sub-field included in the sub-field group is made different from the lowest voltage of the ramp waveform voltage of the sub-field not included in the sub-field group.
    Type: Application
    Filed: January 10, 2008
    Publication date: February 11, 2010
    Applicant: Panasonic Corporation
    Inventors: Takahiko Origuchi, Hidehiko Shoji
  • Publication number: 20090303222
    Abstract: Provided are a plasma display device and a method for driving the plasma display panel. The plasma display device with a panel having high luminance can generate a stable address discharge without increasing the voltage required to generate an address discharge when the current accumulated time of the panel has increased. To achieve this advantage, the plasma display device includes an accumulated-time-measurement-circuit and a scan-electrode-driving-circuit.
    Type: Application
    Filed: November 22, 2007
    Publication date: December 10, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takahiko Origuchi, Hidehiko Shoji
  • Publication number: 20090284446
    Abstract: A plasma display device includes a plasma display panel that has plural scan electrodes and plural sustain electrodes constituting display electrode pairs; and a sustain pulse generating circuit that divides a field period into a plurality of sub fields having an initializing period, an address period, and a sustain period and that generates the sustain pulse with a variable rising slope. The sustain pulse generating circuit generates at least two kinds of sustain pulses in which the rising slope of one sustain pulse is steeper than that of the other sustain pulse in the sustain period of at least one sub field of the plural sub fields and applies the sustain pulse having the steeper rising slope to one electrode of each display electrode pair continuously twice or more at the end of the sustain period.
    Type: Application
    Filed: July 6, 2007
    Publication date: November 19, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Takahiko Origuchi, Hidehiko Shoji, Mitsuo Ueda
  • Publication number: 20090237330
    Abstract: In a plasma display device, a period for connecting display electrode pairs to the base potential is disposed between a sustain pulse for generating the final sustain discharge and the previous sustain pulse based on a lighting ratio of the discharge cells in the corresponding subfield, and a voltage for reducing an interelectrode potential difference of the display electrode pairs is applied to the display electrode pairs in a predetermined time period corresponding to the lighting ratio of the discharge cells in the corresponding subfield after applying the sustain pulse for generating the final sustain discharge to the scan electrodes.
    Type: Application
    Filed: August 9, 2007
    Publication date: September 24, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hidehiko Shoji, Takahiko Origuchi, Toshiyuki Maeda, Mitsuo Ueda, Takayuki Kamatani
  • Publication number: 20090231317
    Abstract: A plasma display panel is driven by providing a plurality of subfields within one field period, the subfield having an initializing period in which the initializing discharge is generated in a discharge cell by applying a ramp-waveform voltage that is gradually descending to a scan electrode, an address period in which an address discharge is generated in the discharge cell by applying a scan pulse voltage to the scan electrode, and a sustain period in which sustain discharges by the number of times corresponding to the luminance weight are generated in the selected discharge cell. The lowest voltage is set of the descending ramp-waveform voltage in the subfield where the luminance weight is the smallest lower than the same voltage in the subfield where the luminance weight is the largest, and a voltage is kept for a prescribed period after the descending ramp-waveform voltage reaches the lowest voltage in the subfield where the luminance weight is the smallest.
    Type: Application
    Filed: February 26, 2007
    Publication date: September 17, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takahiko Origuchi, Hidehiko Shoji, Mitsuo Ueda
  • Patent number: 7583240
    Abstract: In a method of driving a panel, in initializing periods of a plurality of sub-fields constituting one field, one of all-cell initializing operation or selective initializing operation is performed. In the all-cell initializing operation, initializing discharge is performed in all the discharge cells for displaying an image. In the selective initializing operation, initializing discharge is selectively performed only in the discharge cells subjected to sustaining discharge in the sub-field immediately before the sub-filed. According to the average picture level (APL) of the signal of an image to be displayed or the light-emitting rate of a predetermined sub-field, the initializing operation in the initializing period of each sub-field is determined to be one of the all-cell initializing operation and the selective initializing operation.
    Type: Grant
    Filed: January 26, 2005
    Date of Patent: September 1, 2009
    Assignee: Panasonic Corporation
    Inventors: Takeru Yamashita, Hidehiko Shoji, Jumpei Hashiguchi
  • Publication number: 20090179884
    Abstract: A stable address discharge in a plasma display device is generated without increased voltage to cope with increase in the cumulative current-carrying time of a panel with high luminance. A cumulative time calculating circuit for calculating cumulative current-carrying time of the panel and a driving circuit for driving the panel. The driving circuit delivers collected power to the display electrode pairs and clamps each voltage of the display electrode pairs to power-supply voltage and base potential. A sustain period has a period, during which the voltage of the display electrode pairs is clamped to base potential, between the sustain pulse for generating the last sustain discharge in the sustain period and the immediately preceding sustain pulse. The length of the period is changed according to the cumulative current-carrying time calculated by the cumulative time calculating circuit.
    Type: Application
    Filed: December 14, 2007
    Publication date: July 16, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Takahiko Origuchi, Hidehiko Shoji
  • Publication number: 20090146922
    Abstract: An image display device includes a pair of sustain pulse generators for applying either a first sustain pulse or a second sustain pulse to the display electrodes. The first and second sustain pulses generate a sustain discharge twice and once, respectively, in discharge cells when the voltage applied between the display electrodes changes. The application of the first sustain pulse is performed by generating a first discharge by applying a voltage to one of the display electrodes using the clamp corresponding to the one of the display electrodes, and then generating a second discharge by applying a voltage to the other of the display electrodes using the clamp corresponding to the other of the display electrodes. The application of the second sustain pulse is performed by generating a first discharge by applying a voltage to each of the display electrodes using the clamps corresponding to each of the display electrodes.
    Type: Application
    Filed: May 15, 2006
    Publication date: June 11, 2009
    Applicant: PANASONIC CORPORATION
    Inventors: Yutaka Yoshihama, Hidehiko Shoji, Hironari Taniguchi
  • Publication number: 20090135172
    Abstract: In a plasma-display-panel driving method, a field period is divided into a plurality of sub fields, each of which has an address period for allowing discharge cells to selectively generate an address discharge and a sustain period for allowing the discharge cells having generated the address discharge to generate a sustain discharge by a number of times corresponding to a brightness weight. In the sustain period, a period for setting display electrode pairs to the base potential is disposed between the sustain pulse for causing the final sustain discharge in the sustain period and the previous sustain pulse. In a time interval corresponding to the lighting ratio of the discharge cells in the sub field after applying to the display electrode pairs a voltage for generating the final sustain discharge, a voltage for reducing the potential difference between electrodes of the display electrode pairs is applied to the display electrode pairs.
    Type: Application
    Filed: February 5, 2007
    Publication date: May 28, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Hidehiko Shoji, Takahiko Origuchi, Mitsuo Ueda
  • Publication number: 20090122042
    Abstract: One field period includes a plurality of subfields each having an initialization period in which a gradually descending sloping waveform voltage is applied to a scan electrode, a writing period in which a negative scan pulse voltage is applied to the scan electrode, and a sustain period. A sloping waveform voltage is generated by switching a minimum voltage in the sloping waveform voltage between a first voltage and a second voltage that has a lower voltage value than that of the first voltage. The ratio in one field period of a subfield in which an initialization is carried out by the sloping waveform voltage whose minimum voltage is the second voltage is increased when a temperature of the plasma display panel is determined to be low as compared with when the temperature is determined to be not low.
    Type: Application
    Filed: August 3, 2007
    Publication date: May 14, 2009
    Inventors: Takahiko Origuchi, Hidehiko Shoji, Toshiyuki Maeda
  • Publication number: 20090122041
    Abstract: In displaying a predetermined image on a plasma display panel, occurrence of an initializing bright point can be suppressed to reduce the maximum voltage in an all-cell initializing operation, light emission in the all-cell initializing operation is suppressed to reduce the black luminance, and the contrast is sharpened. In driving the plasma display panel, one field period includes a plurality of subfields having a setup period for causing initializing discharge in discharge cells, an address period, and a sustain period. One field period includes at least one subfield for applying ramp waveform voltage increasing in the setup period to the scan electrodes. The maximum voltage of the ramp waveform voltage can be varied.
    Type: Application
    Filed: August 9, 2007
    Publication date: May 14, 2009
    Inventors: Hidehiko Shoji, Takahiko Origuchi
  • Publication number: 20090091514
    Abstract: Plural subfields are provided in one single field period, where each subfield has an initialization period during which a gradient waveform voltage gently falling is applied to a scan electrode to generate initializing discharge in a discharge cell; a writing period during which a scan pulse voltage is applied to a scan electrode to generate writing discharge in a discharge cell; and a sustain period during which sustain discharge is generated in a discharge cell selected, by the number of times corresponding to a luminance weight. The lowest voltage of a falling gradient waveform voltage in a subfield with the smallest luminance weight is set so as to be lower than that with the largest luminance weight. A method of driving a plasma display panel is provided that generates stable writing discharge without increasing voltage required for generating writing discharge even for a large-screen, high-luminance panel.
    Type: Application
    Filed: February 26, 2007
    Publication date: April 9, 2009
    Inventors: Takahiko Origuchi, Hidehiko Shoji, Mitsuo Ueda
  • Publication number: 20090085838
    Abstract: A plasma display device has a cumulative time measuring circuit for measuring the current-flow cumulative time, and a sustain electrode driving circuit. In the sustain electrode driving circuit, one field includes a plurality of subfields having an initializing period for initializing the discharge cells, an address period for selecting discharge cells to be discharged, and a sustain period for causing sustain discharge in the discharge cells selected in the address period. The sustain electrode driving circuit drives the sustain electrode by applying first voltage to the sustain electrode in the initializing period and applying second voltage to the sustain electrode in the address period. The sustain electrode driving circuit varies the value of the second voltage in response to the cumulative time measured by the cumulative time measuring circuit.
    Type: Application
    Filed: December 27, 2007
    Publication date: April 2, 2009
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takahiko Origuchi, Hidehiko Shoji
  • Publication number: 20090015516
    Abstract: A sub-field lighting rate measuring unit measures a lighting rate in a final sub-field. When the measured lighting rate exceeds a threshold value, a blank signal generator maintains a blank signal at a low level in a sustain time period in a sub-field. An output control circuit brings an output control signal into a low level on the basis of the blank signal. In this case, no data pulse is applied to an address electrode, so that there is no power consumed at the time of the rise and the fall of the data pulse.
    Type: Application
    Filed: January 18, 2006
    Publication date: January 15, 2009
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Hidehiko Shoji, Yutaka Yoshihama, Jumpei Hashiguchi, Hironari Taniguchi
  • Publication number: 20080309591
    Abstract: An image display method for allowing an image display device having a large number of pixels arrayed in a planar form to perform an image display by forming one field period from plural sub-fields for which luminance weights to be displayed are determined, and choosing plural luminances among displayable luminances as luminances for display by combining the luminance weights of the sub-fields, so that the respective pixels are controlled not to emit light or to emit light in each sub-field correspondingly to the luminances for display to be displayed. At least one threshold value is set, and when a pixel is allowed to emit light at a luminance for display at or higher than a first threshold value, which is the smallest threshold value, the pixel is controlled not to emit light constantly or to emit light constantly in a sub-field having the smallest luminance weight.
    Type: Application
    Filed: August 4, 2006
    Publication date: December 18, 2008
    Inventors: Hidehiko Shoji, Takahiko Origuchi, Minoru Takeda, Akira Yawata, Hiroko Yamamoto
  • Publication number: 20080252562
    Abstract: A method for driving a plasma display panel including discharge cells at the intersections of data electrodes D1 to Dm and pairs of scan electrodes SC1 to SCn and sustain electrodes SU1 to SUn. One field period is composed of a plurality of subfields each including a wrting period and a sustain period. During the wrting period, a wrting discharge is generated in a selected one of the discharge cells. During the sustain period, a sustain discharge is generated in the selected discharge cell. The voltage to be applied to sustain electrodes SU1 to SUn in the wrting period of the subfield having the lowest display luminance of all the subfields is set higher than the voltage to be applied to sustain electrodes SU1 to SUn in the wrting period of the subfields other than the subfield having the lowest display luminance.
    Type: Application
    Filed: July 14, 2006
    Publication date: October 16, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Hidehiko Shoji, Takahiko Origuchi
  • Publication number: 20080165211
    Abstract: A method for driving a plasma display panel is provided, wherein one field period is structured of a plurality of subfields having a write period for generating write discharges selectively in the discharge cells, and a sustain period for generating the number of times of sustain discharges according to brightness levels in the discharge cells which have generated the write discharges, and in the sustain period, after voltage to generate the last sustain discharge is applied to the display electrode pairs, at time intervals according to the lighting rate of the discharge cells in the subfield, voltage to ease the voltage difference between the electrodes of the display electrode pairs is applied to the display electrode pairs. According to such a structure, it is possible to generate stable write discharges, without increasing voltage necessary for generating the write discharges, even with a large size and high brightness panel.
    Type: Application
    Filed: December 12, 2006
    Publication date: July 10, 2008
    Inventors: Hidehiko Shoji, Takahiko Origuchi, Mitsuo Ueda, Yutaka Yoshihama, Shigeo Kigo