Patents by Inventor Kazuo Okado

Kazuo Okado 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: 10948442
    Abstract: An impedance measuring semiconductor circuit that measures impedance of a specimen. The impedance measuring semiconductor circuit includes an operational amplifier, a resistance coupled between a negative input terminal and an output terminal of the operational amplifier, a D/A converter coupled to a positive input terminal, a switch; an A/D converter that is coupled with the output terminal of the operational amplifier and a one-side terminal of a specimen and measures an output voltage from the operational amplifier and a one-side terminal voltage, and a controller that controls an output voltage from the D/A converter based on a one-side terminal voltage measured by the A/D converter.
    Type: Grant
    Filed: September 12, 2018
    Date of Patent: March 16, 2021
    Assignee: RENESAS ELECTRONICS CORPORATION
    Inventors: Kunihiko Watanabe, Gaku Masumoto, Kazuo Okado
  • Publication number: 20190113472
    Abstract: There is a need to provide an impedance measuring semiconductor circuit and a blood-sugar level meter capable of improving the accuracy of measuring the impedance of a specimen, reducing an area in an analog front-end LSI chip, and reducing the LSI chip size. According to an embodiment, an impedance measuring semiconductor circuit includes: an operational amplifier; a resistance coupled between a negative input terminal and an output terminal of the operational amplifier; a D/A converter coupled to a positive input terminal; a switch; an A/D converter that is coupled with the output terminal of the operational amplifier and a one-side terminal of a specimen and measures an output voltage from the operational amplifier and a one-side terminal voltage; and a controller that controls an output voltage from the D/A converter based on a one-side terminal voltage measured by the A/D converter.
    Type: Application
    Filed: September 12, 2018
    Publication date: April 18, 2019
    Inventors: Kunihiko WATANABE, Gaku MASUMOTO, Kazuo OKADO
  • Patent number: 9354741
    Abstract: The touch panel controller activates a touch panel having a detection plane superposed on a display plane of a display device, and performs a touch detection. The touch panel controller uses a cycle of 1/n (n is a positive integer) of a display frame cycle on the display plane as the detection frame cycle of the detection plane. The touch panel controller decides an order of driving the detection-scan electrodes in each detection frame cycle according to predetermined phase-delay and phase-advance positions with respect to a display-scan electrode drive position of the display device so as to correspond to an order of the detection-scan electrode array of the touch panel. The touch panel controller makes possible to avoid the coincidence of display-scan and touch-detection positions without thinning touch detections even with the detection frame cycle of a touch sensor shorter than the display frame cycle of a liquid crystal panel.
    Type: Grant
    Filed: January 29, 2014
    Date of Patent: May 31, 2016
    Assignee: Synaptics Display Devices GK
    Inventors: Yusuke Uchida, Tatsuya Ishii, Tsuyoshi Kuroiwa, Akihito Akai, Hisayoshi Kajiwara, Kazuo Okado
  • Patent number: 9250740
    Abstract: It becomes possible to use drive pulses having different pulse widths for one kind of drive pulse signal period. Therefore, even if a voltage acting on a crossing part of drive and detection electrodes is periodically changed through a stray capacitance attributed to an external object such as a finger in an undesired manner, the pulse width of the drive pulse is never fixed with respect to the period, and the periodic buildup of a certain voltage on a detection signal, which would make appreciable noise, is suppressed. Thus, the reduction of detection signals can be suppressed in quantity without switching the pulse signal frequency of the drive pulse of a touch panel.
    Type: Grant
    Filed: September 26, 2013
    Date of Patent: February 2, 2016
    Assignee: Synaptics Display Devices GK
    Inventors: Akihito Akai, Tatsuya Ishii, Kazuo Okado
  • Publication number: 20140210750
    Abstract: The touch panel controller activates a touch panel having a detection plane superposed on a display plane of a display device, and performs a touch detection. The touch panel controller uses a cycle of 1/n (n is a positive integer) of a display frame cycle on the display plane as the detection frame cycle of the detection plane. The touch panel controller decides an order of driving the detection-scan electrodes in each detection frame cycle according to predetermined phase-delay and phase-advance positions with respect to a display-scan electrode drive position of the display device so as to correspond to an order of the detection-scan electrode array of the touch panel. The touch panel controller makes possible to avoid the coincidence of display-scan and touch-detection positions without thinning touch detections even with the detection frame cycle of a touch sensor shorter than the display frame cycle of a liquid crystal panel.
    Type: Application
    Filed: January 29, 2014
    Publication date: July 31, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Yusuke Uchida, Tatsuya Ishii, Tsuyoshi Kuroiwa, Akihito Akai, Hisayoshi Kajiwara, Kazuo Okado
  • Publication number: 20140092061
    Abstract: It becomes possible to use drive pulses having different pulse widths for one kind of drive pulse signal period. Therefore, even if a voltage acting on a crossing part of drive and detection electrodes is periodically changed through a stray capacitance attributed to an external object such as a finger in an undesired manner, the pulse width of the drive pulse is never fixed with respect to the period, and the periodic buildup of a certain voltage on a detection signal, which would make appreciable noise, is suppressed. Thus, the reduction of detection signals can be suppressed in quantity without switching the pulse signal frequency of the drive pulse of a touch panel.
    Type: Application
    Filed: September 26, 2013
    Publication date: April 3, 2014
    Applicant: Renesas SP Drivers Inc.
    Inventors: Akihito Akai, Tatsuya Ishii, Kazuo Okado
  • Patent number: 7924252
    Abstract: In consideration of the current leakage path of a liquid crystal panel and a signal line voltage fluctuation due to the current leakage path, a ? adjusting function (second driving method) is applied for each divided period in the first driving method. In a signal line driving unit, a gray scale voltage obtained by adding or subtracting a voltage fluctuation value different in each of the output periods of each gray scale is generated, and a gray scale voltage taking the voltage fluctuation value into consideration is applied to a signal line.
    Type: Grant
    Filed: May 31, 2006
    Date of Patent: April 12, 2011
    Assignee: Renesas Electronics Corporation
    Inventors: Akihito Akai, Yasuyuki Kudo, Takuya Eriguchi, Kazuo Okado
  • Patent number: 7808474
    Abstract: A light control circuit that makes it possible to, when the light intensity of the area surrounding a display screen varies in a relatively short time, prevent the brightness of a backlight from being erroneously adjusted as the result of the variation being detected is provided. The light control circuit controls the backlight of a display panel. This light control circuit is provided with functions of performing the following operation: detection signals from multiple optical sensors are taken into a common sampling means in a time division manner to acquire multiple sampling values temporally dispersed; a surrounding light intensity is determined by majority decision based on the multiple sampling values, and the result of determination is externally outputted.
    Type: Grant
    Filed: December 14, 2006
    Date of Patent: October 5, 2010
    Assignee: Renesas Electronics Corporation
    Inventors: Toshio Mizuno, Takesada Akiba, Kazuo Okado
  • Patent number: 7760178
    Abstract: A liquid crystal display is provided with: a tap adjustment register for adjusting a gray scale level to a gray scale voltage in intermediate portions close to the end portions of the gamma characteristic; and a partial-voltage-ratio adjustment register for adjusting a ratio of a gray scale voltage among a plurality of gray scale levels in the intermediate portions close to the end portions of the gamma characteristic, in addition to an amplitude adjustment register for adjusting an amplitude of a gamma characteristic which determines a relation between gray scale levels and gray scale voltages or brightness levels on a display panel; a gradient adjustment register for adjusting a gradient of intermediate portions of the gamma characteristic while fixing end portions of the gamma characteristic; and a fine adjustment register for finely adjusting the intermediate portions of the gamma characteristic for each gray scale level.
    Type: Grant
    Filed: October 21, 2005
    Date of Patent: July 20, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Naoki Takada, Yasuyuki Kudo, Takuya Eriguchi, Akihito Akai, Kazuo Okado
  • Patent number: 7724269
    Abstract: A display driver used in common for a first screen and a second screen. The display driver includes a data line drive circuit which supplies gray scale voltages to the first and second screens in accordance with display data via data lines in common for the first and second screens, and a scan line drive circuit which supplies scan signals to the first and second screens via scan lines, with the scan lines in the first screen being different from the scan lines in the second screen. The scan line drive circuit scans the second screen in one of a one-line-at-a-time operation and a plural-line-at-a-time operation by using the scan signals every time the scan line drive circuit scans at least one frame of the first screen in a one-line-at-a-time operation by using the scan signals.
    Type: Grant
    Filed: January 30, 2007
    Date of Patent: May 25, 2010
    Assignee: Renesas Technology Corp.
    Inventors: Yasuyuki Kudo, Kazuo Okado, Hiroki Aizawa
  • Publication number: 20100117081
    Abstract: A semiconductor integrated circuit device for driving an LCD, COG chip packaging is performed. To achieve this, an elongate and relatively thick gold bump electrode is formed over an aluminum-based pad having a relatively small area. In a wafer probe test performed after formation of the gold bump electrode, a cantilever type probe needle having gold as a main component and having an almost perpendicularly bent tip portion is used. The diameter of this probe needle in the vicinity of its tip is usually almost the same as the width of the gold bump electrode. This makes it difficult to perform the wafer probe test stably. To counteract this, a plurality of bump electrode rows for outputting a display device drive signal are formed such that the width of inner bump electrodes is made greater than the width of outer bump electrodes.
    Type: Application
    Filed: October 8, 2009
    Publication date: May 13, 2010
    Applicant: RENESAS TECHNOLOGY CORP.
    Inventors: Atsushi OBUCHI, Kazuhisa HIGUCHI, Kazuo OKADO, Kazuto MITSUI, Shusaku MIYATA
  • Patent number: 7643042
    Abstract: A display driver for outputting gradation voltages corresponding to gradation data from an external device to pixels. The display driver includes a generator for generating a plurality of gradation voltages having a plurality of levels based on a reference voltage, and a selector for selecting at least one gradation voltage corresponding to the gradation data from the plurality of gradation voltages generated by the generator. The gradation data includes multi-bits for each color of red, green and blue, and the generator outputs or stops outputting each gradation voltage according to data for color reduction from the external device. The generator stops outputting at least one gradation voltage that is unnecessary for displaying as a result of the color reduction, when the color of the gradation data is reduced according to the data for color reduction.
    Type: Grant
    Filed: April 20, 2005
    Date of Patent: January 5, 2010
    Assignee: Renesas Technology Corporation
    Inventors: Yasuyuki Kudo, Akihito Akai, Kazuo Okado, Toshimitsu Matsudo, Atsuhiro Higa
  • Patent number: 7616221
    Abstract: A driving circuit provided by the present invention is characterized in that the driving circuit selects a gray-scale voltage in accordance with high-order bits of display data from a group of gray-scale voltages with their voltage level varying step by step from fractional time period to fractional time period, which are set in advance, and outputs the selected gray-scale voltage during a time period between the start of a scanning period and a time at which a number assigned to a fractional time period matches quantitative information contained in low-order bits of the display data. In addition, the driving circuit provided by the present invention is also characterized in that the time ratio of the first fractional time period is set at a relatively high value while the time ratios of the second and subsequent fractional time periods are each set at a relatively low value.
    Type: Grant
    Filed: June 30, 2004
    Date of Patent: November 10, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Yasuyuki Kudo, Akihito Akai, Takuya Eriguchi, Kazuo Okado, Hiroki Aizawa
  • Patent number: 7486303
    Abstract: An object of the present invention is to provide a signal line driving circuit capable of easily and optimally adjusting the gamma characteristics of R, G, and B self-emitting element groups (e.g., organic EL element groups) such that each gamma characteristic matches the characteristics of the self-emitting panel by accommodating variations among the characteristics of the R, G, and B self-emitting element groups, thereby providing enhanced image quality and versatility. A self-emitting display driving circuit (a signal line driving circuit) 302 includes 3 gray-scale voltage generating circuits 311 and 3 control registers 308 for R, G, and B self-emitting element groups, respectively, and these gray-scale voltage generating circuits and control registers can be adjusted separately. This arrangement makes it possible to accommodate variations among the characteristics of the R, G, and B self-emitting element groups and thereby provide enhanced image quality on the self-emitting display.
    Type: Grant
    Filed: May 25, 2004
    Date of Patent: February 3, 2009
    Assignee: Renesas Technology Corp.
    Inventors: Akihito Akai, Yasuyuki Kudo, Kazuo Okado
  • Publication number: 20080218500
    Abstract: A liquid crystal display device includes, in one of an even row and an odd row of a liquid crystal panel, a switch for short-circuiting, for example, an even signal line and an odd signal line adjacent on the left side to the even signal line, and a switch for short-circuiting the even signal line and an odd signal line adjacent on the right side to the even signal line provided at an output part of the signal-line driver. By controlling these switches, enlarged display equivalent to the bilinear processing is realized in a horizontal direction. By scanning two scanning lines simultaneously, simple enlarged display is realized in a vertical direction on the panel. Further, by stopping supply of a steady current to an operational amplifier applying data voltage to the even signal line, enlarged display at a low cost and at low power consumption is realized.
    Type: Application
    Filed: January 31, 2008
    Publication date: September 11, 2008
    Inventors: Akihito AKAI, Yasuyuki Kudo, Kazuo Okado
  • Publication number: 20070171182
    Abstract: A light control circuit that makes it possible to, when the light intensity of the area surrounding a display screen varies in a relatively short time, prevent the brightness of a backlight from being erroneously adjusted as the result of the variation being detected is provided. The light control circuit controls the backlight of a display panel. This light control circuit is provided with functions of performing the following operation: detection signals from multiple optical sensors are taken into a common sampling means in a time division manner to acquire multiple sampling values temporally dispersed; a surrounding light intensity is determined by majority decision based on the multiple sampling values, and the result of determination is externally outputted.
    Type: Application
    Filed: December 14, 2006
    Publication date: July 26, 2007
    Inventors: Toshio Mizuno, Takesada Akiba, Kazuo Okado
  • Publication number: 20070139297
    Abstract: A display device mounted on an outside device includes a first display panel, a second display panel, a data driver applying a tone voltage through a common data line, and a scan driver applying a scan signal to the first and second display panels through a scan line for each of the first and second display panels. The display device selects a first display mode or a second display mode in accordance with an instruction from the outside device. The first display mode provides that the first display panel indicates a display state and the second display panel indicates a non-display state, and the second display mode provides that the first display panel indicates the non-display state and the second display panel indicates the display state.
    Type: Application
    Filed: February 12, 2007
    Publication date: June 21, 2007
    Inventors: Yasuyuki Kudo, Toshimitsu Matsudo, Kazuo Okado, Hiroki Aizawa
  • Publication number: 20070120811
    Abstract: A display driver used in common for a first screen and a second screen. The display driver includes a data line drive circuit which supplies gray scale voltages to the first and second screens in accordance with display data via data lines in common for the first and second screens, and a scan line drive circuit which supplies scan signals to the first and second screens via scan lines, with the scan lines in the first screen being different from the scan lines in the second screen. The scan line drive circuit scans the second screen in one of a one-line-at-a-time operation and a plural-line-at-a-time operation by using the scan signals every time the scan line drive circuit scans at least one frame of the first screen in a one-line-at-a-time operation by using the scan signals.
    Type: Application
    Filed: January 30, 2007
    Publication date: May 31, 2007
    Inventors: Yasuyuki Kudo, Kazuo Okado, Hiroki Aizawa
  • Publication number: 20070057884
    Abstract: In consideration of the current leakage path of a liquid crystal panel and a signal line voltage fluctuation due to the current leakage path, a ? adjusting function (second driving method) is applied for each divided period in the first driving method. In a signal line driving unit, a gray scale voltage obtained by adding or subtracting a voltage fluctuation value different in each of the output periods of each gray scale is generated, and a gray scale voltage taking the voltage fluctuation value into consideration is applied to a signal line.
    Type: Application
    Filed: May 31, 2006
    Publication date: March 15, 2007
    Inventors: Akihito Akai, Yasuyuki Kudo, Takuya Eriguchi, Kazuo Okado
  • Patent number: 7180474
    Abstract: A display apparatus includes a data driver that is common to a main screen and a sub screen, and the data driver applies, to the main screen, a tone voltage corresponding to display data from a CPU, and during a vertical blanking time-period of the main screen, the data driver applies, to the sub screen, a tone voltage corresponding to black data or white data, and also includes a scan driver scans the main screen and scans the sub screen during the vertical blanking time-period of the main screen.
    Type: Grant
    Filed: February 6, 2004
    Date of Patent: February 20, 2007
    Assignees: Hitachi, Ltd., Hitachi Displays, Ltd.
    Inventors: Yasuyuki Kudo, Toshimitsu Matsudo, Kazuo Okado, Hiroki Aizawa