Patents by Inventor Tadashi Aoki

Tadashi Aoki 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: 7573472
    Abstract: The present invention discloses an invention about a drive waveform for driving an image display unit. In particular, the present invention discloses the structure of using as a drive waveform a drive waveform signal which is level controlled by a plural of discontinuous levels including a minimum level which is a level corresponding to luminance brightness gradation data which is not 0, at least one non-minimum level which is a level corresponding to larger luminance brightness gradation data, and an intermediate level between the above-described minimum level and the above-described non-minimum level, and is given pulse width control with discontinuous pulse width, and which has a portion, which is controlled with the above-described minimum level, in its trailing edge, and a portion, which is controlled with the above-described intermediate level just before the former portion, when it has the portion controlled by the above-described non-minimum level.
    Type: Grant
    Filed: November 2, 2005
    Date of Patent: August 11, 2009
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Aoki, Kazunori Katakura, Aoji Isono, Kazuhiko Murayama, Kenji Shino
  • Patent number: 7463254
    Abstract: The present invention can provide a driving apparatus capable of compensating an influence of a voltage drop at low costs in a simple manner, which includes: a column driver circuit that generates at least one of modulation signals different in start reference time in one horizontal scanning period and the modulation signals obtained by using pulse width modulation and voltage amplitude modulation in combination; and a correction circuit that corrects a voltage of the row selection signal so as to suppress a voltage variation of the row selection signal, which is caused due to at least a resistance of an output stage of the row driver circuit and a current caused to flow into the resistance.
    Type: Grant
    Filed: June 9, 2006
    Date of Patent: December 9, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
  • Patent number: 7283131
    Abstract: An image display apparatus having a plurality of image forming devices. In an output circuit provided between constant voltage supplies and wiring for driving each of the image forming devices, MOSFETs are successively turned on from the one having a higher ON resistance at the time of switching to make a stepwise transition between outputs from the constant voltage supplies, and have steady potential, thereby limiting undesirable variation in signal potential at the time of switching.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: October 16, 2007
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiko Murayama, Tadashi Aoki, Aoji Isono, Kenji Shino
  • Patent number: 7142178
    Abstract: A modulator includes a modulation circuit for generating modulation signals based on inputted luminance data and for outputting the modulation signals to a plurality of image display elements, each of which is driven by a potential difference between a selection potential applied within a predetermined time period by a selection circuit and the modulation signal. The modulation signal has a waveform which is a combination of a plurality of unit pulses, with the unit pulses having an identical width and n kinds of peak values A1 to An, with n being an integer greater than 1, and A1<. . . <An. Additionally, the unit pulses are combined in such a way that maximal peak value portions of the waveform of the modulation signal are dispersed, and that a rising portion and a falling portion of the waveform have a stair-step-like shape.
    Type: Grant
    Filed: June 12, 2003
    Date of Patent: November 28, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Kenji Shino, Yasuhiko Sano
  • Publication number: 20060256101
    Abstract: A scanning circuit and an image display device in which the influence of losses in a signal path to scanning wiring and a scanning signal output circuit can be reduced. By considering matrix drive in which one row is driven at a time and two or more of the rows are not simultaneously driven, the 480 rows are divided into six modules and one feedback circuit is provided in correspondence with each module to perform feedback control of the output buffers corresponding to 80 rows. An output from a switch is amplified by an operational amplifier and is input as a compensation signal to all the output buffers by an output voltage compensation circuit. Compensation for a voltage drop is made by using the compensation signal for an increase in voltage such that the apparent voltage drop due to the output current is limited to a small value.
    Type: Application
    Filed: July 24, 2006
    Publication date: November 16, 2006
    Applicant: Canon Kabushiki Kaisha
    Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama
  • Patent number: 7126597
    Abstract: A scanning circuit and an image display device in which the influence of losses in a signal path to scanning wiring and a scanning signal output circuit can be reduced. By considering matrix drive in which one row is driven at a time and two or more of the rows are not simultaneously driven, the 480 rows are divided into six modules and one feedback circuit is provided in correspondence with each module to perform feedback control of the output buffers corresponding to 80 rows. An output from a switch is amplified by an operational amplifier and is input as a compensation signal to all the output buffers by an output voltage compensation circuit. Compensation for a voltage drop is made by using the compensation signal for an increase in voltage such that the apparent voltage drop due to the output current is limited to a small value.
    Type: Grant
    Filed: July 30, 2002
    Date of Patent: October 24, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama
  • Publication number: 20060227078
    Abstract: The present invention can provide a driving apparatus capable of compensating an influence of a voltage drop at low costs in a simple manner, which includes: a column driver circuit that generates at least one of modulation signals different in start reference time in one horizontal scanning period and the modulation signals obtained by using pulse width modulation and voltage amplitude modulation in combination; and a correction circuit that corrects a voltage of the row selection signal so as to suppress a voltage variation of the row selection signal, which is caused due to at least a resistance of an output stage of the row driver circuit and a current caused to flow into the resistance.
    Type: Application
    Filed: June 9, 2006
    Publication date: October 12, 2006
    Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
  • Patent number: 7079123
    Abstract: The present invention can provide a driving apparatus capable of compensating an influence of a voltage drop at low costs in a simple manner, which includes: a column driver circuit that generates at least one of modulation signals different in start reference time in one horizontal scanning period and the modulation signals obtained by using pulse width modulation and voltage amplitude modulation in combination; and a correction circuit that corrects a voltage of the row selection signal so as to suppress a voltage variation of the row selection signal, which is caused due to at least a resistance of an output stage of the row driver circuit and a current caused to flow into the resistance.
    Type: Grant
    Filed: June 13, 2003
    Date of Patent: July 18, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
  • Publication number: 20060050030
    Abstract: The present invention discloses an invention about a drive waveform for driving an image display unit. In particular, the present invention discloses the structure of using as a drive waveform a drive waveform signal which is level controlled by a plural of discontinuous levels including a minimum level which is a level corresponding to luminance brightness gradation data which is not 0, at least one non-minimum level which is a level corresponding to larger luminance brightness gradation data, and an intermediate level between the above-described minimum level and the above-described non-minimum level, and is given pulse width control with discontinuous pulse width, and which has a portion, which is controlled with the above-described minimum level, in its trailing edge, and a portion, which is controlled with the above-described intermediate level just before the former portion, when it has the portion controlled by the above-described non-minimum level.
    Type: Application
    Filed: November 2, 2005
    Publication date: March 9, 2006
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tadashi Aoki, Kazunori Katakura, Aoji Isono, Kazuhiko Murayama, Kenji Shino
  • Patent number: 6995516
    Abstract: A drive waveform signal which is level controlled by discontinuous levels including a minimum level corresponding to luminance brightness gradation data which is not 0, at least one non-minimum level corresponding to larger luminance brightness gradation data, and an intermediate level between the minimum and non-minimum level. The signal, which is employed to drive an image display unit, is given pulse width control with discontinuous pulse width, and has a portion, controlled with the minimum level, in its trailing edge, and a portion, controlled with the intermediate level just before the former portion, when it has the portion controlled by the non-minimum level.
    Type: Grant
    Filed: June 13, 2002
    Date of Patent: February 7, 2006
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Aoki, Kazunori Katakura, Aoji Isono, Kazuhiko Murayama, Kenji Shino
  • Publication number: 20060007211
    Abstract: An image display apparatus having a plurality of image forming devices. In an output circuit provided between constant voltage supplies and wiring for driving each of the image forming devices, MOSFETs are successively turned on from the one having a higher ON resistance at the time of switching to make a stepwise transition between outputs from the constant voltage supplies, and have steady potential, thereby limiting undesirable variation in signal potential at the time of switching.
    Type: Application
    Filed: May 13, 2005
    Publication date: January 12, 2006
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kazuhiko Murayama, Tadashi Aoki, Aoji Isono, Kenji Shino
  • Patent number: 6970162
    Abstract: An image display apparatus having a plurality of image forming devices. In an output circuit provided between constant voltage supplies and wiring for driving each of the image forming devices, MOSFETs are successively turned on from the one having a higher ON resistance at the time of switching to make a stepwise transition between outputs from the constant voltage supplies, and have steady potential, thereby limiting undesirable variation in signal potential at the time of switching.
    Type: Grant
    Filed: August 5, 2002
    Date of Patent: November 29, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kazuhiko Murayama, Tadashi Aoki, Aoji Isono, Kenji Shino
  • Patent number: 6909416
    Abstract: A driver IC (integrated circuit) for a display device allowing simple designing and production and yet capable of obviating display quality difference is provided. The driver IC includes a plurality of drive signal output terminals arrange to have variable drive capacities which vary depending on loads of respective signal electrodes of the display device to which the output terminals are connected so as to supply the respective signal electrodes of the display device with drive signal waveforms having identical time constant. The driver IC preferably includes a number of juxtaposed transistors corresponding to but larger in number than the drive signal output terminals, wherein the respective drive signal output terminals are connected to prescribed numbers of transistors so as to have different drive capacities depending on loads of the signal electrodes of the display device to which the output terminals are connected.
    Type: Grant
    Filed: September 23, 2002
    Date of Patent: June 21, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventor: Tadashi Aoki
  • Patent number: 6882329
    Abstract: A drive signal generation circuit which performs gradation control on a load by a drive signal having a stepped waveform. In a case where the wave height value corresponding to input gradation data is Vm (2?m?n), the drive signal is caused to rise in such a manner that each output Vk (2?k?m) is produced one slot after the output V(k?1) to increase the wave height value V0 (reference potential) to Vm in a stepping manner. One slot corresponds to a unit time of the pulse width modulation. The drive signal is caused to fall in such a manner that each output V(k?1) (1?k?m?1) is produced one or two slots after the output Vk to reduce the wave height value from Vm to off level in a stepping manner. A delay circuit is used to delay signals slot by slot. A selection is made from delayed signals according to luminance data to determine a waveform. The circuit is also designed to enable the drive signal waveform rise position to be changed.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: April 19, 2005
    Assignees: Canon Kabushiki Kaisha, Kabushiki Kaisha Toshiba
    Inventors: Aoji Isono, Tadashi Aoki, Kazuhiko Murayama, Kenji Shino, Tsutomu Sakamoto
  • Publication number: 20040060308
    Abstract: Upon a selector operation of a valve such as a four-way selector valve provided in a refrigerating cycle for selecting a channel of fluid, prevention of environmental pollution and energy saving and the like are effectively achieved. A sliding valve is coupled with a piston in a housing of a channel selector valve provided in a refrigerating cycle and the sliding valve moves due to a difference in pressure and so on at both sides of the piston, thereby a channel of fluid is selected. A processing section of a control device is constituted with microcomputers of an indoor and outdoor control sections, while a detecting section of the control device includes temperature sensor, detection means for detecting pressure, detection means for detecting flow rate, detection means for detecting voltage/current, and detection means for detecting frequency.
    Type: Application
    Filed: August 5, 2003
    Publication date: April 1, 2004
    Inventors: Yoshitaka Yoshizawa, Kenji Suzuki, Mitsuaki Noda, Shigeru Kubota, Tadashi Aoki, Hiroshi Ito, Nobuyuki Kiuchi, Seiichi Nakahara
  • Publication number: 20040032405
    Abstract: A modulator circuit (102) is capable of outputting n kinds of unit pulses with the identical width and with peak values A1 to An and controls the peak value and width of a modulation signal through changing the kind and the number of output unit pulses in accordance with luminance data. In case of outputting more than one unit pulse with the maximal peak value out of unit pulses which comprise the modulation signal, the modulator circuit (102) makes the pulses appear dispersedly within an effective light emission time period. With such an arrangement, it is possible to suppress a decrease in display quality otherwise occurring due to voltage drop of row wirings.
    Type: Application
    Filed: June 12, 2003
    Publication date: February 19, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Kenji Shino, Yasuhiko Sano
  • Patent number: 6684651
    Abstract: Upon a selector operation of a valve such as a four-way selector valve provided in a refrigerating cycle for selecting a channel of fluid, prevention of environmental pollution and energy saving and the like are effectively achieved. A sliding valve is coupled with a piston in a housing of a channel selector valve provided in a refrigerating cycle and the sliding valve moves due to a difference in pressure and so on at both sides of the piston, thereby a channel of fluid is selected. A processing section of a control device is constituted with microcomputers of an indoor and outdoor control sections, while a detecting section of the control device includes temperature sensor, detection means for detecting pressure, detection means for detecting flow rate, detection means for detecting voltage/current, and detection means for detecting frequency.
    Type: Grant
    Filed: January 2, 2001
    Date of Patent: February 3, 2004
    Assignee: Kabushiki Kaisha Saginomiya Seisakusho
    Inventors: Yoshitaka Yoshizawa, Kenji Suzuki, Mitsuaki Noda, Shigeru Kubota, Tadashi Aoki, Hiroshi Ito, Nobuyuki Kiuchi, Seiichi Nakahara
  • Publication number: 20040001039
    Abstract: The present invention can provide a driving apparatus capable of compensating an influence of a voltage drop at low costs in a simple manner, which includes: a column driver circuit that generates at least one of modulation signals different in start reference time in one horizontal scanning period and the modulation signals obtained by using pulse width modulation and voltage amplitude modulation in combination; and a correction circuit that corrects a voltage of the row selection signal so as to suppress a voltage variation of the row selection signal, which is caused due to at least a resistance of an output stage of the row driver circuit and a current caused to flow into the resistance.
    Type: Application
    Filed: June 13, 2003
    Publication date: January 1, 2004
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
  • Publication number: 20030063108
    Abstract: A drive signal generation circuit which performs gradation control on a load by a drive signal having a stepped waveform. In a case where the wave height value corresponding to input gradation data is Vm (2≦m≦n), the drive signal is caused to rise in such a manner that each output Vk (2≦k≦m) is produced one slot after the output V(k−1) to increase the wave height value V0 (reference potential) to Vm in a stepping manner. One slot corresponds to a unit time of the pulse width modulation. The drive signal is caused to fall in such a manner that each output V(k−1) (1≦k≦m−1) is produced one or two slots after the output Vk to reduce the wave height value from Vm to off level in a stepping manner. A delay circuit is used to delay signals slot by slot. A selection is made from delayed signals according to luminance data to determine a waveform. The circuit is also designed to enable the drive signal waveform rise position to be changed.
    Type: Application
    Filed: September 27, 2002
    Publication date: April 3, 2003
    Inventors: Aoji Isono, Tadashi Aoki, Kazuhiko Murayama, Kenji Shino, Tsutomu Sakamoto
  • Publication number: 20030052849
    Abstract: A driver IC (integrated circuit) for a display device allowing simple designing and production and yet capable of obviating display quality difference is provided. The driver IC includes a plurality of drive signal output terminals arrange to have variable drive capacities which vary depending on loads of respective signal electrodes of the display device to which the output terminals are connected so as to supply the respective signal electrodes of the display device with drive signal waveforms having identical time constant. The driver IC preferably includes a number of juxtaposed transistors corresponding to but larger in number than the drive signal output terminals, wherein the respective drive signal output terminals are connected to prescribed numbers of transistors so as to have different drive capacities depending on loads of the signal electrodes of the display device to which the output terminals are connected.
    Type: Application
    Filed: September 23, 2002
    Publication date: March 20, 2003
    Inventor: Tadashi Aoki