Patents by Inventor Tsuyoshi Higuchi

Tsuyoshi Higuchi 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: 20100266227
    Abstract: A sliding device includes a sliding bearing, and a shaft which is rotatable and in slidable contact with the sliding bearing in presence of a lubricating oil. The sliding bearing has a surface hardness smaller than a surface hardness of the shaft. Additionally, the sliding bearing has a surface roughness Ra of not larger than 0.2 micrometer, and the shaft has a surface roughness of not larger than 0.05 micrometer.
    Type: Application
    Filed: December 28, 2007
    Publication date: October 21, 2010
    Inventors: Tsuyoshi Higuchi, Yutaka Mabuchi, Benjamin Duffau, Alain Pasgrimaud, Carmelo Gugliotta
  • Publication number: 20100079634
    Abstract: A solid-state image sensor includes a pixel array, and an analog to digital converter for converting a voltage signal read from the pixel array from analog to digital form, wherein the analog to digital converter includes a counter counting a first clock signal for a period depending on a voltage value of the voltage signal, and wherein a least significant bit of a count value of the counter is determined based on an exclusive OR of outputs of two 1-bit counters operating at a frequency of the first clock signal.
    Type: Application
    Filed: September 21, 2009
    Publication date: April 1, 2010
    Applicant: FUJITSU MICROELECTRONICS LIMITED
    Inventor: Tsuyoshi HIGUCHI
  • Patent number: 7639290
    Abstract: A differential amplifier has a first input terminal to which a voltage of a noise signal of the solid-state imaging device is supplied and a second input terminal to which a voltage of a temporary data signal having the noise signal of the solid-state imaging device superposed thereon is supplied. The differential amplifier inverts an output signal when a magnitude relationship in voltage between the first and second input terminals becomes reverse. A measurement circuit measures a variation amount of a voltage of the second input terminal from when the voltage of the second input terminal begins to vary in a direction to reverse the magnitude relationship to when the output signal of the differential amplifier is inverted, and outputs a measurement result as a digital value indicating a voltage of a real data signal obtained by removing the noise signal from the temporary data signal.
    Type: Grant
    Filed: May 27, 2005
    Date of Patent: December 29, 2009
    Assignee: Fujitsu Microelectronics Limited
    Inventors: Tsuyoshi Higuchi, Jun Funakoshi, Seiji Yamagata, Toshitaka Mizuguchi, Katsuyoshi Yamamoto
  • Patent number: 7522199
    Abstract: An imaging device provided with a read circuit in which a light-shielding region is formed in a part of an image region where a plurality of optical/electrical conversion devices is two-dimensionally arrayed in the row and column directions and which converts a optically detected signal outputted from each of the optical/electrical conversion devices for each of the column into a digital signal, comprises a storage device for storing the outputted digital signal outputted in relation with the optical/electrical conversion device in the light-shielding region and a difference calculation device for calculating a difference between the outputted digital signal in relation with the optical/electrical conversion device in a light-receiving region except the light-shielding region and a value stored in the storage device.
    Type: Grant
    Filed: November 24, 2004
    Date of Patent: April 21, 2009
    Assignee: Fujitsu Microelectronics Limited
    Inventors: Jun Funakoshi, Katsuyoshi Yamamoto, Asao Kokubo, Toshitaka Mizuguchi, Tsuyoshi Higuchi
  • Patent number: 7477299
    Abstract: A second source follower circuit of a reference voltage generator includes a transistor having the same characteristics as a first source follower circuit of a pixel. Accordingly, the second source follower circuit can generate a second reference voltage according to the change in characteristics of the first source follower circuit. A noise voltage switching circuit outputs a first voltage as a noise voltage to a pixel signal generator when the noise voltage is equal to or lower than the second reference voltage. In a reset state, the noise voltage and the second reference voltage always have a predetermined voltage difference. Therefore, deterioration in image quality can be prevented even when capturing a subject having high brightness. Since a trimming circuit or the like selecting any one of a plurality of reference voltages according to characteristics of a formed transistor becomes unnecessary, the cost of an imaging device can be reduced.
    Type: Grant
    Filed: May 20, 2005
    Date of Patent: January 13, 2009
    Assignee: Fujitsu Limited
    Inventors: Tsuyoshi Higuchi, Jun Funakoshi, Seiji Yamagata, Toshitaka Mizuguchi, Katsuyoshi Yamamoto
  • Patent number: 7477300
    Abstract: In order to reduce crosstalk caused between control signal wires in a semiconductor apparatus without increasing the size of the semiconductor apparatus, a noise guard circuit is provided at the opposite end of the control signal wire to the driver circuit. The noise guard circuit controls in such a way as to increase the impedance between the relevant control signal wire and a fixed potential when the logic of the relevant control signal wire is positive logic for driving the element, and as to decrease the impedance between the relevant control signal wire and a fixed potential when the logic of the relevant control signal wire is negative logic for driving the element.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: January 13, 2009
    Assignee: Fujitsu Limited
    Inventors: Jun Funakoshi, Tsuyoshi Higuchi
  • Publication number: 20090009822
    Abstract: A solid-state image pickup device and image pickup method eliminate a dark-current component by adjusting the black level appropriately even if the dark-current component varies among horizontal lines. A pixel array includes light-receiving pixel elements and light-blocking pixel elements disposed such that horizontal lines include the light-blocking pixel elements individually. A readout circuit block reads pixel signals of each of the horizontal lines from the pixel array, inputs the pixel signals to ADC circuits (column ADC circuit block), and outputs the pixel signals of the light-blocking pixel elements. A ramp signal generation circuit obtains the pixel signals of the light-blocking pixel elements output from the readout circuit block, generates a ramp signal by using a reference level of AD conversion adjusted for each of the horizontal lines in accordance with the obtained pixel signals of the light-blocking pixel elements, and inputs the ramp signal to the ADC circuits.
    Type: Application
    Filed: September 16, 2008
    Publication date: January 8, 2009
    Applicant: FUJITSU LIMITED
    Inventors: Toshitaka MIZUGUCHI, Katsuyoshi Yamamoto, Jun Funakoshi, Tsuyoshi Higuchi
  • Publication number: 20090002527
    Abstract: A solid-state image sensor where dark current components fluctuating due to temperature changes are removed from pixel signals without reducing resolution during AD conversion. The sensor has a DA converter for generating a reference signal that increases at a constant slope from a predetermined initial signal level, a comparator for comparing the reference signal with a pixel signal, a counter for performing a counting operation in synchronization with increase in the reference signal, a latch circuit for holding as a quantized value of the pixel signal a discrete value at the time when the reference signal and the pixel signal coincide with each other, an average calculator for calculating an average of the quantized values of pixel signals read out from plural light-shielded pixels, and a reference signal adjuster for setting based on the average the initial signal level of the reference signal compared with the pixel signal read out from a light-receiving pixel.
    Type: Application
    Filed: June 26, 2008
    Publication date: January 1, 2009
    Applicant: FUJITSU LIMITED
    Inventor: Tsuyoshi Higuchi
  • Publication number: 20080297636
    Abstract: A solid-state image pickup device having a reduced signal transfer time and a signal processing method using the solid-state image pickup device. A pixel array includes a plurality of light-receiving pixel elements and a plurality of light-blocked pixel elements. A read block reads the output signals of the plurality of light-blocked pixel elements. An AD conversion processing block includes a circuit for summing up the output signals of adjacent light-blocked pixel elements and transferring the signals of the light-blocked pixel elements in a reduced period.
    Type: Application
    Filed: May 30, 2008
    Publication date: December 4, 2008
    Applicant: FUJITSU LIMITED
    Inventors: Toshitaka MIZUGUCHI, Tsuyoshi HIGUCHI
  • Patent number: 7369170
    Abstract: A method for controlling a solid-state imaging apparatus, which includes a plurality of pixels, includes selecting a resetting element of one of the pixels, resetting a detecting unit connected to the pixel, transmitting to a detecting unit, an electric charge accumulated after photoelectric conversion performed by a photoelectric converting element of the pixel, and providing control to set a second end of a transmitting control signal line to an open state.
    Type: Grant
    Filed: November 30, 2004
    Date of Patent: May 6, 2008
    Assignee: Fujitsu Limited
    Inventors: Tsuyoshi Higuchi, Jun Funakoshi, Seiji Yamagata, Toshitaka Mizuguchi, Katsuyoshi Yamamoto
  • Patent number: 7345613
    Abstract: An image processing circuit for reducing noise. The image processing circuit includes a CDS circuit for taking a potential difference between a pixel signal at a reset of an image pickup device and a pixel signal after exposure, and an AD conversion circuit. The AD conversion circuit includes an increment counter and AD conversion clock provided for the AD conversion of the potential difference of the image pickup device between at a reset and after exposure, and an averaging ADC control circuit for averaging a plurality of digital code values obtained through the AD conversion repeated a plurality of times.
    Type: Grant
    Filed: October 12, 2006
    Date of Patent: March 18, 2008
    Assignee: Fujitsu Limited
    Inventor: Tsuyoshi Higuchi
  • Publication number: 20080002044
    Abstract: A photoelectric conversion unit converts a received light into an electric signal. An amplification circuit amplifying the electric signal includes a plurality of elements of which a characteristic value is formed as the same value, an amplifier of which an amplification ratio is determined by a characteristic value of two composite elements constituted by connecting one or more of the elements, a changeover unit for changing over the element constituting each of the composite elements by changing over a connection between the elements, and an averaging unit for averaging outputs of the amplifier, which are obtained at every time of changing over the elements and making the average an output of the amplification circuit.
    Type: Application
    Filed: October 6, 2006
    Publication date: January 3, 2008
    Inventor: Tsuyoshi Higuchi
  • Publication number: 20080001802
    Abstract: An image processing circuit for reducing noise. The image processing circuit includes a CDS circuit for taking a potential difference between a pixel signal at a reset of an image pickup device and a pixel signal after exposure, and an AD conversion circuit. The AD conversion circuit includes an increment counter and AD conversion clock provided for the AD conversion of the potential difference of the image pickup device between at a reset and after exposure, and an averaging ADC control circuit for averaging a plurality of digital code values obtained through the AD conversion repeated a plurality of times.
    Type: Application
    Filed: October 12, 2006
    Publication date: January 3, 2008
    Inventor: Tsuyoshi Higuchi
  • Patent number: 7301487
    Abstract: An image sensor includes: a pixel unit that outputs a first signal including an offset voltage inherent to a pixel; a CDS unit that performs correlated double sampling of a second signal that is obtained from the first signal by canceling the offset voltage inherent to the pixel, and outputs the second signal after the correlated double sampling as a third signal including an offset voltage due to the CDS unit; and an ADC unit that performs analog-to-digital conversion of a fourth signal that is obtained from the third signal by canceling the offset voltage due to the CDS unit.
    Type: Grant
    Filed: May 8, 2006
    Date of Patent: November 27, 2007
    Assignee: Fujitsu Limited
    Inventors: Jun Funakoshi, Toshitaka Mizuguchi, Tsuyoshi Higuchi, Katsuyoshi Yamamoto
  • Patent number: 7218166
    Abstract: A circuit for stabilizing an electric current includes a constant voltage supplying circuit configured to supply a constant voltage, and a current generating circuit coupled to the constant voltage supplying circuit to generate an electric current based on a predetermined voltage responsive to the constant voltage and to adjust a current amount of the electric current to a predetermined amount by feedback control based on comparison of the predetermined voltage with a voltage appearing across a predetermined resistance responsive to the electric current.
    Type: Grant
    Filed: November 19, 2004
    Date of Patent: May 15, 2007
    Assignee: Fujitsu Limited
    Inventors: Makoto Yanagisawa, Jun Funakoshi, Seiji Yamagata, Toshitaka Mizuguchi, Tsuyoshi Higuchi
  • Publication number: 20070075772
    Abstract: The challenge of the present invention is to suppress a variation in brightness of an image and make a reference value of a black level converge at an appropriate value in a short time. Acondition judgment circuit judges whether or not a frame of an amount of change in gains of a variable gain amplifier being equal to or greater than a threshold continues for a predefined frames or more. If a frame of an amount of change in the gains being equal to or greater than the threshold continues for the predefined frames, a black level value of the current frame is set for new black level reference. If not continues for the predetermined number, the previous black level reference value is retained in lieu of correcting the black level.
    Type: Application
    Filed: February 24, 2006
    Publication date: April 5, 2007
    Inventors: Asao Kokubo, Hiroshi Daiku, Jun Funakoshi, Tsuyoshi Higuchi
  • Publication number: 20070052564
    Abstract: An image sensor includes: a pixel unit that outputs a first signal including an offset voltage inherent to a pixel; a CDS unit that performs correlated double sampling of a second signal that is obtained from the first signal by canceling the offset voltage inherent to the pixel, and outputs the second signal after the correlated double sampling as a third signal including an offset voltage due to the CDS unit; and an ADC unit that performs analog-to-digital conversion of a fourth signal that is obtained from the third signal by canceling the offset voltage due to the CDS unit.
    Type: Application
    Filed: May 8, 2006
    Publication date: March 8, 2007
    Inventors: Jun Funakoshi, Toshitaka Mizuguchi, Tsuyoshi Higuchi, Katsuyoshi Yamamoto
  • Patent number: 7145494
    Abstract: A differential comparator which outputs positive and/or negative logic signals to an output terminal according to the coincidence/non-coincidence of first and second input signal levels inputted to first and second input terminals, respectively, comprises an offset cancel function composed of an offset capacitor device provided on the differential comparator side of the first and second terminals, a first switch for short-circuiting the first and second input terminals in such a way as to form a closed loop including the offset capacitor device, and a second switch for short-circuiting both the connection point between the offset capacitor device and the differential comparator, and the output terminal.
    Type: Grant
    Filed: December 10, 2004
    Date of Patent: December 5, 2006
    Assignee: Fujitsu Limited
    Inventors: Toshitaka Mizuguchi, Jun Funakoshi, Seiji Yamagata, Tsuyoshi Higuchi
  • Publication number: 20060176383
    Abstract: In order to reduce crosstalk caused between control signal wires in a semiconductor apparatus without increasing the size of the semiconductor apparatus, a noise guard circuit is provided at the opposite end of the control signal wire to the driver circuit. The noise guard circuit controls in such a way as to increase the impedance between the relevant control signal wire and a fixed potential when the logic of the relevant control signal wire is positive logic for driving the element, and as to decrease the impedance between the relevant control signal wire and a fixed potential when the logic of the relevant control signal wire is negative logic for driving the element.
    Type: Application
    Filed: June 2, 2005
    Publication date: August 10, 2006
    Inventors: Jun Funakoshi, Tsuyoshi Higuchi
  • Publication number: 20060170795
    Abstract: A differential amplifier has a first input terminal to which a voltage of a noise signal of the solid-state imaging device is supplied and a second input terminal to which a voltage of a temporary data signal having the noise signal of the solid-state imaging device superposed thereon is supplied. The differential amplifier inverts an output signal when a magnitude relationship in voltage between the first and second input terminals becomes reverse. A measurement circuit measures a variation amount of a voltage of the second input terminal from when the voltage of the second input terminal begins to vary in a direction to reverse the magnitude relationship to when the output signal of the differential amplifier is inverted, and outputs a measurement result as a digital value indicating a voltage of a real data signal obtained by removing the noise signal from the temporary data signal.
    Type: Application
    Filed: May 27, 2005
    Publication date: August 3, 2006
    Inventors: Tsuyoshi Higuchi, Jun Funakoshi, Seiji Yamagata, Toshitaka Mizuguchi, Katsuyoshi Yamamoto