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).
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Patent number: 7573472Abstract: 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: GrantFiled: November 2, 2005Date of Patent: August 11, 2009Assignee: Canon Kabushiki KaishaInventors: Tadashi Aoki, Kazunori Katakura, Aoji Isono, Kazuhiko Murayama, Kenji Shino
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Patent number: 7463254Abstract: 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: GrantFiled: June 9, 2006Date of Patent: December 9, 2008Assignee: Canon Kabushiki KaishaInventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
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Patent number: 7283131Abstract: 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: GrantFiled: May 13, 2005Date of Patent: October 16, 2007Assignee: Canon Kabushiki KaishaInventors: Kazuhiko Murayama, Tadashi Aoki, Aoji Isono, Kenji Shino
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Patent number: 7142178Abstract: 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: GrantFiled: June 12, 2003Date of Patent: November 28, 2006Assignee: Canon Kabushiki KaishaInventors: Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Kenji Shino, Yasuhiko Sano
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Publication number: 20060256101Abstract: 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: ApplicationFiled: July 24, 2006Publication date: November 16, 2006Applicant: Canon Kabushiki KaishaInventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama
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Patent number: 7126597Abstract: 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: GrantFiled: July 30, 2002Date of Patent: October 24, 2006Assignee: Canon Kabushiki KaishaInventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama
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Publication number: 20060227078Abstract: 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: ApplicationFiled: June 9, 2006Publication date: October 12, 2006Inventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
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Patent number: 7079123Abstract: 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: GrantFiled: June 13, 2003Date of Patent: July 18, 2006Assignee: Canon Kabushiki KaishaInventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
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Publication number: 20060050030Abstract: 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: ApplicationFiled: November 2, 2005Publication date: March 9, 2006Applicant: CANON KABUSHIKI KAISHAInventors: Tadashi Aoki, Kazunori Katakura, Aoji Isono, Kazuhiko Murayama, Kenji Shino
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Patent number: 6995516Abstract: 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: GrantFiled: June 13, 2002Date of Patent: February 7, 2006Assignee: Canon Kabushiki KaishaInventors: Tadashi Aoki, Kazunori Katakura, Aoji Isono, Kazuhiko Murayama, Kenji Shino
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Publication number: 20060007211Abstract: 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: ApplicationFiled: May 13, 2005Publication date: January 12, 2006Applicant: CANON KABUSHIKI KAISHAInventors: Kazuhiko Murayama, Tadashi Aoki, Aoji Isono, Kenji Shino
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Patent number: 6970162Abstract: 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: GrantFiled: August 5, 2002Date of Patent: November 29, 2005Assignee: Canon Kabushiki KaishaInventors: Kazuhiko Murayama, Tadashi Aoki, Aoji Isono, Kenji Shino
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Patent number: 6909416Abstract: 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: GrantFiled: September 23, 2002Date of Patent: June 21, 2005Assignee: Canon Kabushiki KaishaInventor: Tadashi Aoki
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Patent number: 6882329Abstract: 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: GrantFiled: September 27, 2002Date of Patent: April 19, 2005Assignees: Canon Kabushiki Kaisha, Kabushiki Kaisha ToshibaInventors: Aoji Isono, Tadashi Aoki, Kazuhiko Murayama, Kenji Shino, Tsutomu Sakamoto
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Publication number: 20040060308Abstract: 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: ApplicationFiled: August 5, 2003Publication date: April 1, 2004Inventors: Yoshitaka Yoshizawa, Kenji Suzuki, Mitsuaki Noda, Shigeru Kubota, Tadashi Aoki, Hiroshi Ito, Nobuyuki Kiuchi, Seiichi Nakahara
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Publication number: 20040032405Abstract: 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: ApplicationFiled: June 12, 2003Publication date: February 19, 2004Applicant: CANON KABUSHIKI KAISHAInventors: Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Kenji Shino, Yasuhiko Sano
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Patent number: 6684651Abstract: 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: GrantFiled: January 2, 2001Date of Patent: February 3, 2004Assignee: Kabushiki Kaisha Saginomiya SeisakushoInventors: Yoshitaka Yoshizawa, Kenji Suzuki, Mitsuaki Noda, Shigeru Kubota, Tadashi Aoki, Hiroshi Ito, Nobuyuki Kiuchi, Seiichi Nakahara
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Publication number: 20040001039Abstract: 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: ApplicationFiled: June 13, 2003Publication date: January 1, 2004Applicant: CANON KABUSHIKI KAISHAInventors: Kenji Shino, Tadashi Aoki, Aoji Isono, Kazuhiko Murayama, Yasuhiko Sano
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Publication number: 20030063108Abstract: 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: ApplicationFiled: September 27, 2002Publication date: April 3, 2003Inventors: Aoji Isono, Tadashi Aoki, Kazuhiko Murayama, Kenji Shino, Tsutomu Sakamoto
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Publication number: 20030052849Abstract: 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: ApplicationFiled: September 23, 2002Publication date: March 20, 2003Inventor: Tadashi Aoki