Patents by Inventor Akira Torisawa

Akira Torisawa 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: 6459721
    Abstract: A receiving apparatus includes a base-band conversion circuit, a synchronizing circuit/code generator and a demodulator. The base-band conversion circuit converts a received signal into a base-band signal. The synchronizing circuit/code generator detects a spread code included in the received signal to generate a plurality of spread codes in synchronization with the spread code included in the received signal. The demodulator uses the plurality of spread codes supplied by the synchronizing circuit/code generator to demodulate the base-band signal.
    Type: Grant
    Filed: October 29, 1998
    Date of Patent: October 1, 2002
    Assignee: Canon Kabushiki Kaisha
    Inventors: Norihiro Mochizuki, Katsuo Saito, Akira Torisawa, Toshihiko Myojo, Ichiro Kato, Tetsuo Kanda, Atsushi Takasaki, Kazuo Moritomo, Rie Suzuki
  • Patent number: 6122068
    Abstract: An image forming apparatus includes a scan unit for scanning a light beam modulated based on an image signal in the main scan direction, and a drive unit for rotating an image carrier in the subscan direction of an image. The rotation period of the image carrier is set to be an integer multiple of the scan period in the main scan direction of the light beam by the scan unit.
    Type: Grant
    Filed: December 14, 1995
    Date of Patent: September 19, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akira Torisawa, Eihiro Sakaki, Fumihiro Ueno
  • Patent number: 6020672
    Abstract: A surface acoustic wave converter for converting an electric signal into a surface acoustic wave includes an interdigital transducer provided on a piezoelectric substrate. The interdigital transducer has first and second electrode groups each having one or more electrode fingers to which a first signal is almost simultaneously inputted. The surface acoustic wave converters includes first input unit for inputting the first signal to the one or more electrode fingers of the first electrode group, and second input unit for inputting the first signal to the one or more electrode fingers of the second electrode group when at least one of surface acoustic waves excited by the first signal in the one or more electrode fingers of the first electrode group reaches one of the one or more electrode fingers of the second electrode group.
    Type: Grant
    Filed: September 26, 1996
    Date of Patent: February 1, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akane Yokota, Akira Torisawa, Koichi Egara, Tadashi Eguchi, Akihiro Koyama, Takahiro Hachisu
  • Patent number: 5962950
    Abstract: In a surface acoustic wave apparatus, a surface acoustic wave element for obtaining a convolution signal is housed in a recess of a substrate. Since the surface acoustic wave element is housed in the recess of the substrate in this surface acoustic wave apparatus, the apparatus can be compactified. This effect of compactification is remarkable, because the surface acoustic wave element has an output electrode for obtaining the convolution signal and thus originally has a big element size. When a laminate substrate is used as the substrate, a configuration for effectively using surfaces of respective layers may be arranged in such a manner that output wiring of the convolution signal is separately formed in the layers. This further enhances the effect of compactification. There are further disclosed a spread spectrum signal receiver using the above surface acoustic wave apparatus for receiving a spread spectrum signal, and a spread spectrum communication system using the spread spectrum signal receiver.
    Type: Grant
    Filed: April 10, 1996
    Date of Patent: October 5, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Koichi Egara, Akira Torisawa, Tadashi Eguchi, Akihiro Koyama, Takahiro Hachisu, Akane Yokota
  • Patent number: 5856997
    Abstract: A receiving apparatus includes a base-band conversion circuit, a synchronizing circuit/code generator and a demodulator. The base-band conversion circuit converts a received signal into a base-band signal. The synchronizing circuit/code generator detects a spread code included in the received signal to generate a plurality of spread codes in synchronization with the spread code included in the received signal. The demodulator uses the plurality of spread codes supplied by the synchronizing circuit/code generator to demodulate the base-band signal.
    Type: Grant
    Filed: October 20, 1995
    Date of Patent: January 5, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Norihiro Mochizuki, Katsuo Saito, Akira Torisawa, Toshihiko Myojo, Ichiro Kato, Tetsuo Kanda, Atsushi Takasaki, Kazuo Moritomo, Rie Suzuki
  • Patent number: 5815055
    Abstract: A matched filter has an input IDT and an output IDT, and also has a device for preventing propagating surface acoustic waves from diverging. By preventing the divergence of surface acoustic waves, signals obtained in units of electrode finger pairs of the output IDT are uniformed. Furthermore, this application also discloses the following arrangement. That is, an arrangement for converging surface acoustic waves is adopted, and the width of surface acoustic waves input to the output IDT is set to be larger than at least the crossing width of electrode fingers, nearest to the input IDT, of those of the output IDT, so that some surface acoustic waves propagate along non-crossing portions of the electrode fingers, on the input IDT side, of those of the output IDT. With this arrangement, the influence of the crossing portions of the electrode fingers, closer to the input IDT, on the surface acoustic waves input to the crossing portions of the electrode fingers, farther from the input IDT, can be relaxed.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: September 29, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Eguchi, Akira Torisawa, Koichi Egara, Akihiro Koyama, Takahiro Hachisu, Akane Yokota
  • Patent number: 5760525
    Abstract: A surface acoustic wave device includes a piezoelectric substrate, first and second input transducers formed on the substrate and adapted for respectively generating surface acoustic waves corresponding to input signals, the first and second input transducers each having a shape to focus the surface acoustic waves generated thereby, an output transducer formed between the first and second input transducers on the substrate and adapted for obtaining a convolution -signal of the surface acoustic waves generated by the first and second input transducers, and conductive films, one formed between the first input transducer and the output transducer and another between the second input transducer and the output transducer on the substrate.
    Type: Grant
    Filed: July 23, 1996
    Date of Patent: June 2, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takahiro Hachisu, Akira Torisawa, Norihiro Mochizuki, Koichi Egara, Tadashi Eguchi, Akihiro Koyama
  • Patent number: 5754303
    Abstract: An image processing apparatus includes a first delay generation circuit, requiring no high-frequency clocks, for obtaining a pixel formation start timing signal from a digital input signal, a second delay generation circuit, requiring no high-frequency clocks, for obtaining a pixel formation end timing signal from the digital input signal, and a unit for obtaining a pixel formation interval signal from the pixel formation start and end timing signals.
    Type: Grant
    Filed: June 24, 1996
    Date of Patent: May 19, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasuo Ito, Akira Torisawa, Eihiro Sakaki, Masaki Ohtake, Fumihiro Ueno
  • Patent number: 5717274
    Abstract: A surface acoustic wave device includes a piezoelectric substrate, a wave guide path provided on the piezoelectric substrate and an interdigital transducer for exciting a surface acoustic wave. The interdigital transducer is provided with plural portions of mutually different pitches of the electrode finger, respectively corresponding to different frequencies. The portions are parallelly arranged along a direction perpendicular to the propagation direction of the surface acoustic wave. The surface acoustic wave generated by the interdigital transducer is entered in concentrated manner into the wave guide path.
    Type: Grant
    Filed: January 29, 1997
    Date of Patent: February 10, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Eguchi, Akira Torisawa, Norihiro Mochizuki, Koichi Egara, Akihiro Koyama, Takahiro Hachisu
  • Patent number: 5638191
    Abstract: An image forming apparatus includes a scan unit for scanning a light beam modulated based on an image signal in the main scan direction, and a drive unit for rotating an image carrier in the subscan direction of an image. The rotation period of the image carrier is set to be an integer multiple of the scan period in the main scan direction of the light beam by the scan unit.
    Type: Grant
    Filed: March 19, 1996
    Date of Patent: June 10, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akira Torisawa, Eihiro Sakaki, Fumihiro Ueno
  • Patent number: 5629781
    Abstract: This disclosure relates to an image forming and processing apparatus having a plurality of storage device capable of forming an image at a high speed by reading image data in parallel. Since a predetermined quantity of image data is stored in a plurality of hard discs, and the image data is read from the hard discs to a double buffer in parallel, an image can be formed continuously at a high speed. Another structure is arranged in a manner such that images are stored in hard discs of an optional number and the images are transmitted to a printer engine by using a FIFO (First In First Out) buffer which corresponds to the hard discs. Therefore, an image can be transmitted continuously at a high speed asynchronously with the printer output.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: May 13, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumihiro Ueno, Akira Torisawa, Yasuo Ito, Eihiro Sakaki, Masaki Ohtake, Hiromi Kataoka, Atsushi Kashihara, Kaoru Seto
  • Patent number: 5596426
    Abstract: This disclosure relates to an image forming and processing apparatus having a plurality of storage devices capable of forming an image at a high speed by reading image data in parallel. Since a predetermined quantity of image data is stored in a plurality of hard discs, and the image data is read from the hard discs to a double buffer in parallel, an image can be formed continuously at a high speed. Another structure is arranged in a manner such that images are stored in hard discs of an optional number and the images are transmitted to a printer engine by using a FIFO (First In First Out) buffer which corresponds to the hard discs. Therefore, an image can be transmitted continuously at a high speed asynchronously with the printer output.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 21, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Fumihiro Ueno, Akira Torisawa, Yasuo Ito, Eihiro Sakaki, Masaki Ohtake, Hiromi Kataoka, Atsushi Kashihara, Kaoru Seto
  • Patent number: 5539687
    Abstract: A correlator includes a reference signal generating device for generating a reference signal with period T, n-convolvers each having an action time of T/n where n is an integer of at least 2, into each of which an information signal and a reference signal are input and each of which outputs a convolution signal of the information signal and the reference signal, a delay device for delaying an information signal input into a k-th convolver among the n convolvers for a time of (k-1)T/n where k=1, 2, . . . , n and for delaying a reference signal input into the k-th convolver for a time of (n-k)T/n, and an adder for adding convolution signals respectively output from the n convolvers. A receiver includes such a correlator for outputting a correlation signal of a received information signal and a reference signal, and a decoding circuit for decoding data from the correlation signal output from the correlator.
    Type: Grant
    Filed: December 15, 1993
    Date of Patent: July 23, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akira Torisawa, Koichi Egara, Tadashi Eguchi
  • Patent number: 5477098
    Abstract: A surface acoustic wave device includes a piezoelectric substrate, a wave guide path provided on the piezoelectric substrate and an interdigital transducer for exciting a surface acoustic wave. The interdigital transducer is provided with plural portions of mutually different pitches of the electrode finger, respectively corresponding to different frequencies. The portions are parallelly arranged along a direction perpendicular to the propagation direction of the surface acoustic wave. The surface acoustic wave generated by the interdigital transducer is entered in concentrated manner into the wave guide path.
    Type: Grant
    Filed: May 31, 1994
    Date of Patent: December 19, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Tadashi Eguchi, Akira Torisawa, Norihiro Mochizuki, Koichi Egara, Akihiro Koyama, Takahiro Hachisu
  • Patent number: 5457487
    Abstract: A color image forming apparatus forms a color image by superposing images of plural colors in plane-sequential manner. In the color image forming apparatus, the amount of aberration between the detection signal for the recording medium for the first color and the horizontal synchronization signal is measured by a counter, and the start timing of image formation of the second and subsequent colors is controlled by a delay device, according to the measured amount of aberration.
    Type: Grant
    Filed: December 30, 1992
    Date of Patent: October 10, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Eihiro Sakaki, Hidekazu Tominaga, Yasuo Ito, Akira Torisawa, Masaki Ohtake, Tetsuya Kobayashi, Fumihiro Ueno, Tomohiro Hashimoto, Eiichiro Teshima
  • Patent number: 5097189
    Abstract: A recording apparatus in which a stepping motor is used as a driving source to reciprocate a carriage on which a recording head is mounted and recording is executed by the recording head in accordance with the timing when the stepping motor rotates. The apparatus includes a rotational position detector to detect a rotational position of the stepping motor; a current switching circuit to switch energization currents to the stepping motor on the basis of a detection signal from the rotational position detector; a motor speed control circuit to closed loop control a rotational speed of the stepping motor through the current switching circuit; and a controller for detecting a load corresponding to the stepping motor by a speed control output from the motor speed control circuit and for controlling the motor so as to change output torque of the stepping motor in accordance with the load.
    Type: Grant
    Filed: July 12, 1990
    Date of Patent: March 17, 1992
    Assignee: Canon Kabushiki Kaisha
    Inventors: Noriaki Ito, Akira Torisawa
  • Patent number: 5075609
    Abstract: A recording apparatus in which the movement of a recording head for recording scanning is effected includes a carriage carrying the recording head thereon, a step motor for moving the carriage, a linear encoder for detecting the amount of movement of the carriage, the linear encoder being installed over the movement range of the carriage and generating pulse signals in conformity with the amount of movement of the carriage, a controller for counting the pulse signals from the linear encoder and outputting a control signal for the starting and stoppage of the carriage in conformity with the count value, and current switch-over device for switching over and controlling an energization current supplied to the coil of the step motor in conformity with the pulse signals from the linear encoder.
    Type: Grant
    Filed: May 31, 1990
    Date of Patent: December 24, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Noriaki Ito, Akira Torisawa
  • Patent number: 5029264
    Abstract: The present invention provides a recording apparatus wherein recording is performed by reciprocably shifting a carriage on which a recording head is mounted by means of a stepping motor and which comprises a rotational position detection device for detecting a rotational position of a rotor of the stepping motor, and a control unit for performing a closed loop control for the change-over timing of excitation currents to coils of the stepping motor and for the driving speed of the stepping motor, on the basis of the detection signal from the rotational position detection device, and judges whether the initial drive of the stepping motor and the change-over timing are normal, through the control unit.
    Type: Grant
    Filed: September 27, 1989
    Date of Patent: July 2, 1991
    Assignee: Canon Kabushiki Kaisha
    Inventors: Noriaki Ito, Akira Torisawa, Masaaki Kakizaki
  • Patent number: 4972109
    Abstract: A stepping motor comprising a rotor having magnetic poles on the peripheral surface thereof at a predetermined pitch, first and second stator yoke units each having pole teeth at the predetermined pitch and disposed with deviation of 1/4 pitch therebetween relative to the rotor, and a coil for exciting the first and second stator yoke units, characterized by means for adjusting the phase deviation between the first and second stator yoke units.
    Type: Grant
    Filed: December 8, 1988
    Date of Patent: November 20, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Masaaki Kakizaki, Akira Torisawa, Noriaki Ito
  • Patent number: 4963808
    Abstract: A motor control apparatus disclosed in this invention counts output signals from an encoder upon rotation of a rotor, and performs energization switching of a motor coil when the count value has reached a predetermined value.
    Type: Grant
    Filed: August 30, 1989
    Date of Patent: October 16, 1990
    Assignee: Canon Kabushiki Kaisha
    Inventors: Akira Torisawa, Noriaki Itou, Masaaki Kakizaki, Hiroshi Kato, Shigeru Okamura