Patents by Inventor Hiraku Kozuka

Hiraku Kozuka 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: 20030057431
    Abstract: In order to reduce the capacitance of a light-receiving element, the present invention provides a light-receiving element comprises a first semiconductor region of the first conductivity type, a second semiconductor region of the second conductivity type, provided on the first semiconductor region, a third semiconductor region of the first conductivity type, provided between the second semiconductor region and an insulating film and an electrode region of the second conductivity type, provided in the second semiconductor region where the third semiconductor region is absent on and above the second semiconductor region, and connected to an anode or cathode electrode consisting of a conductor.
    Type: Application
    Filed: October 31, 2002
    Publication date: March 27, 2003
    Applicant: CANON KABUSHIKI KAISHA
    Inventors: Hiraku Kozuka, Toru Koizumi, Koji Sawada
  • Patent number: 6538693
    Abstract: In a one-dimensional or two-dimensional photoelectric converting apparatus for simultaneously executing an accumulation of a photosignal and an output of a signal, in order to remove a reset noise of a sensor unit and to reduce a random noise, the apparatus has a photosensor, a resetting circuit of the photosensor, noise signal holding elements for holding a noise signal when a resetting operation of the photosensor is executed, and a noise signal removing circuit for removing a noise from the signal accumulated in the photosensor after completion of the same resetting operation by using the noise signal held.
    Type: Grant
    Filed: January 21, 1997
    Date of Patent: March 25, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiraku Kozuka
  • Patent number: 6534757
    Abstract: This invention has as its object to provide an image sensor chip and an image sensor using the image sensor chip capable of reducing random noise in the image sensor chip to obtain a high-quality image. An image sensor chip having a plurality of light-receiving element includes a noise reduction circuit for reducing random noise contained in an output signal from the light-receiving element in the ON state and outputting the random noise contained in the output signal from the light-receiving element without any processing in the OFF state, a first control circuit for controlling the ON/OFF state of the noise reduction circuit, a clamp circuit for clamping an output signal output through the noise reduction circuit to a reference potential, and a second control circuit for controlling an ON/OFF state of the clamp circuit. An image sensor chip and an image sensor formed by arraying a plurality of image sensor chips are also provided.
    Type: Grant
    Filed: January 25, 1999
    Date of Patent: March 18, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumihiro Inui, Takamasa Sakuragi, Hiraku Kozuka
  • Patent number: 6531690
    Abstract: For implementing optional setting of resolutions in a main scanning direction and in a sub-scanning direction and attaining of higher recording speed in a low resolution mode, a photoelectric conversion apparatus is provided with a plurality of photodetectors arrayed in the main scanning direction and in the sub-scanning direction, and a resolution switching circuit for effecting switching between resolutions by selecting read signals to be read from the photodetectors arrayed in the main scanning direction and in the sub-scanning direction.
    Type: Grant
    Filed: May 2, 2000
    Date of Patent: March 11, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiraku Kozuka
  • Patent number: 6528832
    Abstract: An image sensor having a plurality of photodetectors and a source follower, storing photo-charges generated by the photodetectors in gate of a MOS transistor and outputting voltage signals converted from the photo-charges, integrally formed on a single semiconductor substrate. The source follower is configured with p-channel MOS transistors to restrain generation of stray carrier. Further, the p-channel MOS transistor of the source follower on the power source side is formed on an n-type well whose impurity concentration is higher than that of an n-type semiconductor substrate where the p-channel MOS transistor on the ground side is formed. In this configuration, the absolute value of the threshold voltage of the p-channel MOS transistor on the ground side becomes lower than that of the p-channel MOS transistor on the power source side, thus gain of the source follower is increased.
    Type: Grant
    Filed: October 6, 2000
    Date of Patent: March 4, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Sawada, Hiraku Kozuka
  • Publication number: 20030020000
    Abstract: For implementing optional setting of resolutions in a main scanning direction and in a sub-scanning direction and attaining of higher recording speed in a low resolution mode, a photoelectric conversion apparatus is provided with a plurality of photodetectors arrayed in the main scanning direction and in the sub-scanning direction, and a resolution switching circuit for effecting switching between resolutions by selecting read signals to be read from the photodetectors arrayed in the main scanning direction and in the sub-scanning direction.
    Type: Application
    Filed: May 2, 2000
    Publication date: January 30, 2003
    Inventor: Hiraku Kozuka
  • Patent number: 6473538
    Abstract: To obtain an excellent image signal, an image sensor having a plurality of photoelectric conversion devices each including a plurality of light-receiving elements includes a resolution switching circuit for switching a resolution of a signal read from the light-receiving element, a scanning circuit for reading a signal from the light-receiving element in accordance with the resolution switched by the resolution switching circuit, and a start timing control circuit for controlling a start timing from one of the photoelectric conversion devices to the next photoelectric conversion device in accordance with the resolution switched by the resolution switching circuit.
    Type: Grant
    Filed: February 17, 1999
    Date of Patent: October 29, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiraku Kozuka
  • Patent number: 6437309
    Abstract: A photoelectric transducer having a CMOS constant-current-source circuit which can reduce fixed-pattern noise even if the CMOS constant-current-source circuit and photosensors are formed in the same semiconductor substrate is provided. The photoelectric transducer includes a constant-current-source circuit in which a current mirror circuit including pMOS transistors and a current mirror circuit including nMOS transistors are subjected to tandem connection between power supplies, and a plurality of photosensors formed by a second-conduction-type semiconductor formed near a surface of a first-conduction-type semiconductor substrate. The constant-current-source circuit and the plurality of photosensors are formed on the same semiconductor substrate. A voltage drop circuit is provided at one of tandem connection portions of the current mirror circuits in order to suppress stray carriers present near the plurality of photosensors.
    Type: Grant
    Filed: October 24, 2000
    Date of Patent: August 20, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiraku Kozuka, Shigetoshi Sugawa
  • Publication number: 20020070331
    Abstract: This invention has as its object to provide an image sensor chip and an image sensor using the image sensor chip capable of reducing random noise in the image sensor chip to obtain a high-quality image. An image sensor chip having a plurality of light-receiving element includes a noise reduction circuit for reducing random noise contained in an output signal from the light-receiving element in the ON state and outputting the random noise contained in the output signal from the light-receiving element without any processing in the OFF state, a first control circuit for controlling the ON/OFF state of the noise reduction circuit, a clamp circuit for clamping an output signal output through the noise reduction circuit to a reference potential, and a second control circuit for controlling an ON/OFF state of the clamp circuit. An image sensor chip and an image sensor formed by arraying a plurality of image sensor chips are also provided.
    Type: Application
    Filed: January 25, 1999
    Publication date: June 13, 2002
    Inventors: FUMIHIRO INUI, TAKAMASA SAKURAGI, HIRAKU KOZUKA
  • Publication number: 20020063199
    Abstract: A photoelectric conversion apparatus is comprised of a light-receiving element having a first semiconductor region of a first conduction type, and a second semiconductor region of a second conduction type for storing a charge generated by photoelectric conversion adjacent to the first semiconductor region, a readout electrode for reading a signal based on the charge stored in the second semiconductor region; and at least a pair of electrode portions spaced from each other along a photoreceptive surface so as to place a photoreceptive portion of the second semiconductor region in between, and connected to the first semiconductor region. Applied to the pair of electrode portions is a voltage that completely depletes the photoreceptive portion of the second semiconductor region and that can create a potential gradient for moving the charge stored in the second semiconductor region, to the readout electrode side.
    Type: Application
    Filed: November 21, 2001
    Publication date: May 30, 2002
    Inventor: Hiraku Kozuka
  • Publication number: 20020044699
    Abstract: To obtain an excellent image signal, an image sensor having a plurality of photoelectric conversion devices each including a plurality of light-receiving elements includes a resolution switching circuit for switching a resolution of a signal read from the light-receiving element, a scanning circuit for reading a signal from the light-receiving element in accordance with the resolution switched by the resolution switching circuit, and a start timing control circuit for controlling a start timing from one of the photoelectric conversion devices to the next photoelectric conversion device in accordance with the resolution switched by the resolution switching circuit.
    Type: Application
    Filed: February 17, 1999
    Publication date: April 18, 2002
    Inventor: HIRAKU KOZUKA
  • Patent number: 6303951
    Abstract: Photoelectric conversion chips having the same structure are disposed in line and electrically connected together to constitute a multi-chip type image sensor. The gate of a load transistor of a source follower circuit of each of the photoelectric conversion chips is connected in common to one constant current source circuit. The constant current source circuit and photoelectric conversion chips are mounted on a substrate. With this structure, the common current source circuit is used for all the source follower circuits so that noises will not be generated on the photoelectric conversion chip unit basis. The multi-chip type image sensor can therefore improve the image quality, and horizontal or vertical stripes to be caused by noises otherwise generated in separate constant current source circuits can be removed.
    Type: Grant
    Filed: April 10, 2000
    Date of Patent: October 16, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Sawada, Hiraku Kozuka
  • Patent number: 6184516
    Abstract: A photoelectric conversion device and an image sensor having a plurality of photodetectors and peripheral circuits, configured with MOS transistors, which are integrally formed on a semiconductor substrate. In the peripheral circuits, including a MOS operational amplifier, for outputting electric signals obtained from the photodetectors to outside, a source follower using an n-channel MOS transistor and a source follower using a p-channel MOS transistor are formed subsequent to the MOS operational amplifier. Output from the MOS operational amplifier enters the gate of the source follower of the n-channel MOS transistor, output from the source follower of the n-channel MOS transistor enters the gate of the source follower using a p-channel MOS transistor, and output from the source follower of the p-channel MOS transistor enters a negative input terminal of the MOS operational amplifier as well as is outputted to outside to drive an external load.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: February 6, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Sawada, Hiraku Kozuka
  • Patent number: 6169317
    Abstract: To make the thickness of an interlevel insulating film uniform and suppress variations in output signal, in a photoelectric conversion element including a plurality of photoelectric conversion portions, and light-shielding units having openings formed above the photoelectric conversion portions, the light-shielding units have first light-shielding layers, and second light-shielding layers formed on the first light-shielding layers via an interlevel insulating film. The first light-shielding layers have gaps (GP) for allowing two adjacent openings (OP) to communicate with each other. The second light-shielding layers have light-shielding portions (12a) above the gaps of the first light-shielding layers.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: January 2, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Sawada, Hiraku Kozuka, Shigeru Nishimura
  • Patent number: 6163024
    Abstract: A photoelectric transducer having a CMOS constant-current-source circuit which can reduce fixed-pattern noise even if the CMOS constant-current-source circuit and photosensors are formed in the same semiconductor substrate is provided. The photoelectric transducer includes a constant-current-source circuit in which a current mirror circuit including pMOS transistors and a current mirror circuit including nMOS transistors are subjected to tandem connection between power supplies, and a plurality of photosensors formed by a second-conduction-type semiconductor formed near a surface of a first-conduction-type semiconductor substrate. The constant-current-source circuit and the plurality of photosensors are formed on the same semiconductor substrate. A voltage drop circuit is provided at one of tandem connection portions of the current mirror circuits in order to suppress stray carriers present near the plurality of photosensors.
    Type: Grant
    Filed: May 28, 1998
    Date of Patent: December 19, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiraku Kozuka, Shigetoshi Sugawa
  • Patent number: 6150682
    Abstract: An image sensor having a plurality of photodetectors and a source follower, storing photo-charges generated by the photodetectors in gate of a MOS transistor and outputting voltage signals converted from the photo-charges, integrally formed on a single semiconductor substrate. The source follower is configured with p-channel MOS transistors to restrain generation of stray carrier. Further, the p-channel MOS transistor of the source follower on the power source side is formed on an n-type well whose impurity concentration is higher than that of an n-type semiconductor substrate where the p-channel MOS transistor on the ground side is formed. In this configuration, the absolute value of the threshold voltage of the p-channel MOS transistor on the ground side becomes lower than that of the p-channel MOS transistor on the power source side, thus gain of the source follower is increased.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: November 21, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koji Sawada, Hiraku Kozuka
  • Patent number: 6150704
    Abstract: There are provided a photoelectric conversion apparatus which comprises a light-receiving element including a semiconductor substrate of a first conductivity type, a first semiconductor region of a second conductivity type formed on the surface of the semiconductor substrate, a transparent insulating layer formed on the semiconductor substrate, and a light-shielding layer formed on the insulating layer and having an opening with an area larger than the first semiconductor region, and in which the light-receiving element includes a plurality of first semiconductor regions in a single opening, and the first semiconductor regions in the single opening are electrically connected to each other, and an image sensor using the apparatus.
    Type: Grant
    Filed: October 1, 1998
    Date of Patent: November 21, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiraku Kozuka
  • Patent number: 6118115
    Abstract: A photoelectric conversion apparatus is provided which can reduce FPNs as much as possible even if there is an unbalanced quantity between the capacitance values of a light signal capacitor CTS and a noise signal capacitor CTN, and can suppress FPNs as much as possible from being varied with irregular process precision degrees and operation conditions.
    Type: Grant
    Filed: July 14, 1998
    Date of Patent: September 12, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiraku Kozuka, Shigetoshi Sugawa, Yoshio Koide
  • Patent number: 6002157
    Abstract: In a photoelectric conversion device driven by a current mirror circuit, the current mirror circuit is constituted by four transistors, e.g., first and second PMOS transistors and first and second NMOS transistors. A photodiode which has a cathode connected to the drain of the second PMOS transistor and receives reverse bias is arranged. Electrons generated in the photodiode can prevent potential rise of a node connected to the photodiode to normally operate the photoelectric conversion device even upon irradiation of light.
    Type: Grant
    Filed: February 11, 1999
    Date of Patent: December 14, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiraku Kozuka
  • Patent number: 5998779
    Abstract: Disclosed is a photoelectric conversion apparatus including a photoelectric conversion unit, a plurality of output lines to which a signal output from the photoelectric conversion unit is read out, a unit for resetting the plurality of output lines to a fixed potential, and a unit for directly connecting the plurality of output lines.
    Type: Grant
    Filed: December 18, 1997
    Date of Patent: December 7, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventor: Hiraku Kozuka