Patents by Inventor Jun Ashiwa

Jun Ashiwa 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: 7330321
    Abstract: A method of simultaneously recording multiple reference magnetic signals by using a magnetic head having multiple recording portions is provided. A writing yoke formed of a ferromagnetic material thin film and a back yoke are provided to a side wall of a slider, which is formed of a hard ceramic, as a distal end portion of the magnetic head. After forming the yokes to the slider, grooves are formed by focused ion beam machining from the slider side. All of the materials of the slider, the back yoke, and the writing yoke are thus locally removed. Magnetic writing is thus blocked by the grooves, and magnetic recording is only performed by four recording portions of the writing yoke.
    Type: Grant
    Filed: July 8, 2004
    Date of Patent: February 12, 2008
    Assignee: Canon Kabushiki Kaisha
    Inventor: Jun Ashiwa
  • Patent number: 6923522
    Abstract: Each of pixels of recorded image is formed by a plurality of dots composed with ink droplets ejected from a plurality of different orifices at individual different main-scannings. With this recording process, the variation of ink ejection characteristics between a plurality of orifices in a recording head can be reduced in forming pixels.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: August 2, 2005
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideki Tanaka, Yasuyuki Tamura, Hiroto Takahashi, Shinji Takagi, Makoto Shioya, Masayoshi Tachihara, Tatsuo Kimura, Jun Ashiwa
  • Publication number: 20050013043
    Abstract: A method of simultaneously recording multiple reference magnetic signals by using a magnetic head having multiple recording portions is provided. A writing yoke formed of a ferromagnetic material thin film and a back yoke are provided to a side wall of a slider, which is formed of a hard ceramic, as a distal end portion of the magnetic head. After forming the yokes to the slider, grooves are formed by focused ion beam machining from the slider side. All of the materials of the slider, the back yoke, and the writing yoke are thus locally removed. Magnetic writing is thus blocked by the grooves and, and magnetic recording is only performed by four recording portions of the writing yoke.
    Type: Application
    Filed: July 8, 2004
    Publication date: January 20, 2005
    Inventor: Jun Ashiwa
  • Publication number: 20030090537
    Abstract: Each of pixels of recorded image is formed by a plurality of dots composed with ink droplets ejected from a plurality of different orifices at individual different main-scannings. With this recording process, the variation of ink ejection characteristics between a plurality of orifices in a recording head can be reduced in forming pixels.
    Type: Application
    Filed: September 16, 2002
    Publication date: May 15, 2003
    Applicant: Canon Kabushiki Kaisha
    Inventors: Hideki Tanaka, Yasuyuki Tamura, Hiroto Takahashi, Shinji Takagi, Makoto Shioya, Masayoshi Tachihara, Tatsuo Kimura, Jun Ashiwa
  • Patent number: 6513906
    Abstract: Each of pixels of recorded image is formed by a plurality of dots composed with ink droplets ejected from a plurality of different orifices at individual different main-scannings. With this recording process, the variation of ink ejection characteristics between a plurality of orifices in a recording head can be reduced in forming pixels.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: February 4, 2003
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hideki Tanaka, Yasuyuki Tamura, Hiroto Takahashi, Shinji Takagi, Makoto Shioya, Masayoshi Tachihara, Tatsuo Kimura, Jun Ashiwa
  • Patent number: 6260939
    Abstract: A liquid jet recording method of recording on a recording material with liquid droplets discharged trough plural scanning nozzles, in which: n/(s/p)≧2 n/(s/p)×k=g−1 are satisfied, where n (n≧2) is a number of the nozzles arranged at pitch P (&mgr;m); s (&mgr;m) is a distance of relative movement between the nozzles and the recording material between adjacent scans; k (k≧1) is a maximum number of ink droplets per pixel and per scan; g (g≧3) is a number of tone levels.
    Type: Grant
    Filed: December 1, 1998
    Date of Patent: July 17, 2001
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Shioya, Yasuyuki Tamura, Hiroto Takahashi, Masayoshi Tachihara, Tadashi Yamamoto, Genji Inada, Tatsuo Kimura, Jun Ashiwa
  • Patent number: 6043622
    Abstract: A one-phase electromagnetic motor drive controller includes a one-phase electromagnetic motor, a position detection mechanism for detecting a rotational position of the motor and a control mechanism for controlling the drive of the one-phase electromagnetic motor from the detected rotational position. When the torque constant of the motor is used as a parameter of a control calculation, the torque constant parameter is corrected by the relationship between it and the rotational position of the electromagnetic motor.
    Type: Grant
    Filed: April 23, 1998
    Date of Patent: March 28, 2000
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroyuki Shiomi, Naoki Kawamata, Jun Ashiwa
  • Patent number: 5930066
    Abstract: An apparatus records information on a hard disk with a magnetic head arm provided in a hard disk drive. The apparatus comprises an interference measuring system, containing an outgoing portion for a measuring light beam to the arm and a reference light forming portion, for obtaining relative displacement information with respect to the arm by interfering the reference light with reflected light of the measuring light from the arm or a slider belonging to the arm, the interference measuring system having a light beam deflecting member for deflecting the measuring light and thus guiding the measuring light to a lateral surface of the arm or of the slider, a control system for generating a signal for positioning the arm with respect to the hard disk on the basis of the relative displacement information obtained by the interference measuring system, and a signal system for transmitting a signal for recording information on the hard disk to the magnetic head.
    Type: Grant
    Filed: August 26, 1997
    Date of Patent: July 27, 1999
    Assignee: Canon Kabushiki Kaisha
    Inventors: Kou Ishizuka, Hidejiro Kadowaki, Naoki Kawamata, Hiroyuki Hagiwara, Jun Ashiwa
  • Patent number: 5812250
    Abstract: A Doppler velocimeter determines a state of noise generation in a detection signal including a Doppler signal component based on comparison by a preceding/succeeding-signal comparator for comparing the detection signals before and after passing through a band-pass filter for cutting noise adjusted to the frequency of the detection signal, and/or includes a filter circuit for determining passage/interruption of the detection signal after passing through the band-pass filter from a relationship between the count value of a first counter, in which the output of a first frequency multiplier for multiplying the frequency of the detection signal by N is made to be a clock signal and a leading edge in the detection signal is made to be a reset trigger, and a leading edge in the detection signal, and/or includes an error signal generator for generating an error detection signal by detecting a periodic error in the detection signal after passing through the band-pass filter from a relationship between the count value
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: September 22, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasuhiko Ishida, Hidejiro Kadowaki, Makoto Takamiya, Jun Ashiwa, Shigeki Kato, Shinji Ueda
  • Patent number: 5777640
    Abstract: A liquid jet recording method for recording on a recording material with liquid droplets discharged through plural scanning nozzles arranged in a width measured in a direction of main scan. The recording method includes a first main scan by relative movement between the nozzles and the recording material, in which pixels are recorded with numbers of droplets through a nozzle, the numbers of droplets corresponding to respective tone signals. The method also includes a sub-scan by relative movement between the nozzles and the recording material in a direction crossing with a movement direction of the first main scan. The method further includes a second main scan in which the pixels are recorded with numbers of droplets through a different nozzle, the latter numbers of droplets corresponding to tone level signals. The sub-scan and second main scan steps are repeated to record a tone image by discharging plural droplets for a pixel.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: July 7, 1998
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Shioya, Yasuyuki Tamura, Hiroto Takahashi, Masayoshi Tachihara, Tadashi Yamamoto, Genji Inada, Tatsuo Kimura, Jun Ashiwa
  • Patent number: 5696578
    Abstract: This invention has as its object to provide a frequency tracking method, a frequency control apparatus (tracking apparatus) using this method, and a Doppler velocity meter using the same, which easily and quickly allow the center frequency of a band pass filter to coincide with the frequency of an input signal even when an input signal suffers from a large level drift.
    Type: Grant
    Filed: May 13, 1993
    Date of Patent: December 9, 1997
    Assignee: Canon Kabushiki Kaisha
    Inventors: Yasuhiko Ishida, Hidejiro Kadowaki, Makoto Takamiya, Jun Ashiwa, Shigeki Kato, Shinji Ueda
  • Patent number: 5552879
    Abstract: A Doppler velocimeter includes an illuminating system for projecting a light beam for measurement onto an object to be measured at a predetermined working distance, and a light-receiving system for receiving light from the object illuminated with the light beam by the illuminating system. Information relating to a speed of the object is detected by a Doppler shift of the light received by the light-receiving system. The Doppler velocimeter further includes a changing device for changing the working distance of the illuminating system.
    Type: Grant
    Filed: August 4, 1994
    Date of Patent: September 3, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Takamiya, Hidejiro Kadowaki, Yasuhiko Ishida, Jun Ashiwa, Shigeki Kato, Shinji Ueda
  • Patent number: 5517222
    Abstract: An ink jet recording apparatus which has at least one ink jet recording head to perform recording on a recording medium held on a rotary drum by discharging liquid ink from discharging nozzles, comprises a receptor, arranged on the rotary drum at a position which does not overlap with a position at which a recording medium is placed, for receiving ink droplets discharged by the ink jet recording head not for recording.
    Type: Grant
    Filed: February 14, 1995
    Date of Patent: May 14, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Hiroshi Sugiyama, Kousuke Yamamoto, Yoshitaka Okamura, Jun Ashiwa
  • Patent number: 5502466
    Abstract: A position information detection apparatus includes a first detection system for radiating two collimated light beams onto an object to be measured at a predetermined crossing angle to form interference fringes at a predetermined interval, and detecting scattered light emanating from the object to be measured by the interference fringes at the predetermined interval, a second detection system for radiating two light beams onto the object to be measured at a predetermined crossing angle to form interference fringes having a gradient with each other in an opposing direction to the object to be measured, and detecting scattered light emanating from the object to be measured by the interference fringes having the gradient, and a detection unit for comparing output signals from the first and second detection systems, and detecting relative position information, along the opposing direction of the first and second detection systems, of the object to be measured.
    Type: Grant
    Filed: June 28, 1994
    Date of Patent: March 26, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shigeki Kato, Hidejiro Kadowaki, Yasuhiko Ishida, Makoto Takamiya, Jun Ashiwa, Shinji Ueda
  • Patent number: 5483332
    Abstract: A doppler velocimeter determines the velocity of an object moving through a beam intersection area by using a doppler frequency obtained by detecting light from the beam intersecting area. The doppler velocimeter includes: a light source; a diffraction grating for diffracting light received from the light source; first and second lens systems for transmitting diffracted light from the diffraction grating to irradiate a portion of a movable object to be examined, the first and second lens systems having the same focal length F; and a detector device for receiving light from the portion of the object irradiated with the light which has been transmitted through the first and second lens systems and for obtaining a doppler signal used for velocity determination. The interval between the first and second lens systems is twice as long as the focal length F.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: January 9, 1996
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Takamiya, Jun Ashiwa, Hidejiro Kadowaki, Yasuhiko Ishida
  • Patent number: 5430469
    Abstract: A liquid jet recording method of recording on a recording material with liquid droplets discharged trough plural scanning nozzles, in which:n/(s/p).gtoreq.2n/(s/p).times.k=g-1are satisfied,where n (n.gtoreq.2) is a number of the nozzles arranged at pitch P (.mu.m); s (.mu.m) is a distance of relative movement between the nozzles and the recording material between adjacent scans; k (k.gtoreq.1) is a maximum number of ink droplets per pixel and per scan; g (g.gtoreq.3) is a number of tone levels.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: July 4, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Makoto Shioya, Yasuyuki Tamura, Hiroto Takahashi, Masayoshi Tachihara, Tadashi Yamamoto, Genji Inada, Tatsuo Kimura, Jun Ashiwa
  • Patent number: 5384587
    Abstract: After an ink-jet recording head with a plurality of discharging portions arranged is main-scanned in a direction perpendicular to the direction of the discharging portion arrangement to record a first image area, sub-scanning of the head is performed. Before the head is main-scanned to record a second image area, the sub-scanning is performed so that a few discharging portions on an upper edge portion of the head in second main-scanning overlap part of the first image area. Ink droplets land on pixels in the overlapping portion twice for each main-scanning, and image density of the pixels in the overlapping portion is controlled by the sum number of the landing ink droplets. This enables image density unevenness of image density, example, a "black stripe (banding)" or a "white stripe (banding)" in a boundary of an image area being recorded in each main-scanning, to be markedly reduced.
    Type: Grant
    Filed: June 3, 1992
    Date of Patent: January 24, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Shinji Takagi, Hideki Tanaka, Tatsuo Kimura, Jun Ashiwa
  • Patent number: 4283697
    Abstract: A high frequency filter for frequencies higher than the VHF band comprises a closed conductive housing, a pair of input and/or output means like an antenna provided at both the extreme ends of said housing, a plurality of resonators arranged on a straight line between said antennas, each of said resonators having an elongated inner conductor and a cylindrical dielectric body surrounding said inner conductor, one end of each of said resonators being fixed on the single plane of the housing and the other end of each of said resonators being free standing, and the length between each of the resonators being defined according to the specified coupling coefficient for the desired characteristics of the filter.The present filter utilizes the coupling effect between resonators by the displacement current relating to surface TM mode and the conductive current relating to TEM mode. Therefore, no coupling means for providing the coupling between resonators is provided.
    Type: Grant
    Filed: November 9, 1979
    Date of Patent: August 11, 1981
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Yoshio Masuda, Atsushi Fukasawa, Jun Ashiwa, Takuro Sato
  • Patent number: 4255729
    Abstract: A high frequency filter for frequencies higher than the VHF band comprising at least one resonator has been found. Each resonator comprises a conductive housing, an inner conductor one end of which is fixed at the bottom of the housing and the other end of which is free standing, a cylindrical dielectric body surrounding said inner conductor, and the diameter of the dielectric body is approximately four times as large as that of said inner conductor.
    Type: Grant
    Filed: May 9, 1979
    Date of Patent: March 10, 1981
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Atsushi Fukasawa, Jun Ashiwa, Takuro Sato