Patents by Inventor Hiroyoshi Funato

Hiroyoshi Funato 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: 20040213133
    Abstract: In a diffraction grating used in an optical head device leading light, diffracted light exiting from each of the plurality of areas is lead to a corresponding particular photo-detecting area of the photodetector. Each of the plurality of areas of the diffraction grating is produced either by first two-beam interference exposure to interference fringes from first divergent light from a position equivalent to a light emitting point on the light source of the optical head device and second divergent light form a position equivalent to a light receiving point corresponding to each photo-detecting area, or by second two-beam interference exposure to interference fringes from first convergent light converging at the position equivalent to the light emitting point on the light source and second convergent light converging at the point equivalent to the light receiving point corresponding to each photo-detecting area.
    Type: Application
    Filed: April 23, 2004
    Publication date: October 28, 2004
    Inventors: Hiroyoshi Funato, Masanori Kobayashi, Kazuya Miyagaki, Hiroyuki Sugimoto
  • Patent number: 6754162
    Abstract: In an optical pickup method and device of the present invention, a grating unit separates a light beam, emitted by a light source, into a 0th order diffracted beam and 1st order diffracted beams. An objective lens focuses the diffracted beams, sent from the grating unit, onto a recording surface of an optical recording medium through a transparent substrate of the medium, so that a main spot is formed on the recording surface by the 0th order diffracted beam and sub-spots, interposing the main spot therebetween, are formed on the recording surface by the 1st order diffracted beams. A reflection beam detector receives reflection beams from the main spot and the sub-spots of the medium to generate detection signals from the received reflection beams.
    Type: Grant
    Filed: July 2, 2001
    Date of Patent: June 22, 2004
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuhiro Fujita, Hiroyoshi Funato, Hiroshi Koide
  • Publication number: 20040017760
    Abstract: An optical pickup apparatus includes first and second light sources which selectively emit one of first and second light beams, the first and second light beams being different in wavelength, the wavelengths of the first and second light beams being appropriate for accessing first and second optical disks respectively. A coupling lens converts a corresponding one of the first and second light beams into a collimated beam. An objective lens forms a light spot on a corresponding one of the first and second optical disks by focusing the collimated beam. A holographic optical element receives a reflection beam of the light spot from one of the first and second optical disks and provides holographic effects on the reflection beam so as to diffract the reflection beam in predetermined diffracting directions depending on the wavelength of the reflection beam.
    Type: Application
    Filed: July 18, 2003
    Publication date: January 29, 2004
    Inventor: Hiroyoshi Funato
  • Publication number: 20040013076
    Abstract: A polarization diffraction grating includes two media having different orientation states arranged alternately and cyclically, wherein each boundary between the media forms an oblique rectangular shape.
    Type: Application
    Filed: April 16, 2003
    Publication date: January 22, 2004
    Inventors: Hiroyoshi Funato, Junichi Kitabayashi, Shigeru Oohchida, Tsuyoshi Suzudo
  • Patent number: 6618344
    Abstract: An optical pickup apparatus includes first and second light sources which selectively emit one of first and second light beams, the first and second light beams being different in wavelength, the wavelengths of the first and second light beams being appropriate for accessing first and second optical disks respectively. A coupling lens converts a corresponding one of the first and second light beams into a collimated beam. An objective lens forms a light spot on a corresponding one of the first and second optical disks by focusing the collimated beam. A holographic optical element receives a reflection beam of the light spot from one of the first and second optical disks and provides holographic effects on the reflection beam so as to diffract the reflection beam in predetermined diffracting directions depending on the wavelength of the reflection beam.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: September 9, 2003
    Assignee: Ricoh Company, Ltd.
    Inventor: Hiroyoshi Funato
  • Publication number: 20030072047
    Abstract: An optical pickup unit includes a light source of semiconductor laser chips of different light-emission wavelengths; a plurality of holograms placed between the light source and an optical recording medium, the holograms including at least one non-polarization hologram having a substantially uniform diffraction efficiency irrespective of the direction of polarization of incident light and at least one polarization hologram having a diffraction efficiency varying depending on the direction of polarization of incident light; and a wave plate provided between the optical recording medium and the polarization hologram. The returning beam of a light beam emitted from a selected one of the semiconductor laser chips is diffracted by the corresponding one of said holograms to be received by a light-receiving element. The wave plate turns the direction of polarization of the returning beam to a different direction from that of the emitted light beam.
    Type: Application
    Filed: September 26, 2002
    Publication date: April 17, 2003
    Inventors: Hiroyoshi Funato, Shigeru Oohchida
  • Publication number: 20020003755
    Abstract: In an optical pickup method and device of the present invention, a grating unit separates a light beam, emitted by a light source, into a 0th order diffracted beam and 1st order diffracted beams. An objective lens focuses the diffracted beams, sent from the grating unit, onto a recording surface of an optical recording medium through a transparent substrate of the medium, so that a main spot is formed on the recording surface by the 0th order diffracted beam and sub-spots, interposing the main spot therebetween, are formed on the recording surface by the 1st order diffracted beams. A reflection beam detector receives reflection beams from the main spot and the sub-spots of the medium to generate detection signals from the received reflection beams.
    Type: Application
    Filed: July 2, 2001
    Publication date: January 10, 2002
    Applicant: Ricoh Company, Ltd.
    Inventors: Kazuhiro Fujita, Hiroyoshi Funato, Hiroshi Koide
  • Publication number: 20010026523
    Abstract: An optical pickup apparatus used in an optical data recording/reproducing apparatus for reading/reproducing data on an optical recording medium, including a light source, a diffracting device configured to transmit a light beam and to diffract a light beam reflected from the optical recording medium, an optical device having a reflecting portion and a transmitting portion configured to reflect one part of the light beam emitted from the light source and to transmit another part of the light beam to the optical recording medium and from the optical recording medium, and a photodetecting device to detect the light beam from the optical recording medium for signal light detection, and the light beam reflected by the reflecting portion of the optical device for monitor light detection of the light source.
    Type: Application
    Filed: March 8, 2001
    Publication date: October 4, 2001
    Inventors: Shigeru Ohuchida, Hiroyoshi Funato
  • Patent number: 6072579
    Abstract: An optical pickup apparatus includes first and second light sources which selectively emit one of first and second light beams, the first and second light beams being different in wavelength, the wavelengths of the first and second light beams being appropriate for accessing first and second optical disks respectively. A coupling lens converts a corresponding one of the first and second light beams into a collimated beam. An objective lens forms a light spot on a corresponding one of the first and second optical disks by focusing the collimated beam. A holographic optical element receives a reflection beam of the light spot from one of the first and second optical disks and provides holographic effects on the reflection beam so as to diffract the reflection beam in predetermined diffracting directions depending on the wavelength of the reflection beam.
    Type: Grant
    Filed: August 24, 1999
    Date of Patent: June 6, 2000
    Assignee: Ricoh Company, Ltd.
    Inventor: Hiroyoshi Funato
  • Patent number: 5684779
    Abstract: An optical head which records data onto an optical data recording medium and reproduces the data therefrom includes a laser light source, a collimator lens, an objective lens, a light splitting device arranged between the laser light source and the objective lens, for splitting the emitted light from the laser light and a reflected light from the optical data recording medium. A diffraction grating is provided to which only the reflected light split at the light splitting device is incident to, and which leads the reflected light split at the optical element onto a photo-detector. Thereby, an optical head of high effectiveness in utilization of light and low cost can be obtained.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: November 4, 1997
    Assignee: Ricoh Company, Ltd.
    Inventors: Shigeru Ohuchida, Hiroyoshi Funato
  • Patent number: 5481636
    Abstract: A wavelength conversion element includes a substrate made of LiTaO.sub.3 of non-linear medium, a three-dimensional waveguide formed in the substrate and a second harmonic generation portion for defining a change in refractive index in the waveguide with a period .LAMBDA. and generating a second harmonic of a fundamental wave introduced into the wave guide, where .LAMBDA.=2 m.pi./{.beta.(2.omega.)-2.beta.(.omega.)}, m is a natural number, .omega. is a frequency of fundamental harmonic, .beta.(.omega.) is a propagation constant of the fundamental wave, and .beta.(2.omega.) is a propagation constant of second harmonic.
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: January 2, 1996
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroaki Fukuda, Hiroyoshi Funato, Shigeyoshi Misawa
  • Patent number: 5402154
    Abstract: An optical shutter device comprises an electro-optic layer of a material that shows the electro-optic Kerr effect, an array of shutter regions defined on the electro-optic layer for controlling a passage of an optical beam through the layer, a plurality of electrodes provided on the electro-optic layer in correspondence to the shutter regions for applying a predetermined electric field upon energization, a driver circuit connected to each pair of the electrodes for energizing the same independently from each other, a biasing circuit connected to the plurality of electrodes for applying a predetermined d.c. bias voltage thereto, a switching circuit for inverting the polarity of the d.c.
    Type: Grant
    Filed: August 7, 1992
    Date of Patent: March 28, 1995
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Shibaguchi, Hiroyoshi Funato
  • Patent number: 5355220
    Abstract: An optical movement measuring method and apparatus measures a movement of an object. A light from a light source is irradiated on a diffraction grating which is provided on the object so as to generate diffracted lights of different order of diffraction. The diffraction grating has light transmitting portions and light blocking portions which are alternately and periodically arranged. Interference fringes which comprises bright and dark stripes which occur alternately and are generated by overlapping spots of diffracted lights of different order of diffraction are detected, and a movement of the object is measured based on a counted number of stripes of the detected interference fringes.
    Type: Grant
    Filed: August 21, 1992
    Date of Patent: October 11, 1994
    Assignees: Ricoh Company, Ltd., Hiroshi Kobayashi, Haruhiko Machida
    Inventors: Hiroshi Kobayashi, Haruhiko Machida, Jun Akedo, Tomoyuki Yamaguchi, Hiroyoshi Funato
  • Patent number: 5333231
    Abstract: A wavelength conversion element includes a substrate made of LiTaO.sub.3 of non-linear medium, a three-dimensional waveguide formed in the substrate and a second harmonic generation portion for defining a change in refractive index in the waveguide with a period .LAMBDA. and generating a second harmonic of a fundamental wave introduced into the wave guide, where .LAMBDA.=2m.pi./{.beta.(2.omega.)-2.beta.(.omega.)}, m is a natural number, .omega. is a frequency of fundamental harmonic, .beta.(.omega.) is a propagation constant of the fundamental wave, and .beta.(2.omega.) is a propagation constant of second harmonic.
    Type: Grant
    Filed: April 30, 1992
    Date of Patent: July 26, 1994
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroaki Fukuda, Hiroyoshi Funato, Shigeyoshi Misawa
  • Patent number: 5208800
    Abstract: A magneto-optical signal detection device comprising a thin film type optical waveguide unit having a substrate on which a waveguide is formed. The unit has a coupling portion for coupling two polarization components simultaneously in a same plane of the waveguide as a TE mode and a TM mode. The modes TE and TM are included in reflection light reflected from a magneto-optical recording medium and perpendicular to each other. The unit also has a TE-TM mode separating portion having a taper boundary. A waveguide layer is gradually thinned in the taper boundary toward an outer end thereof.
    Type: Grant
    Filed: April 11, 1991
    Date of Patent: May 4, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Tami Isobe, Shigeyoshi Misawa, Kiyoshi Yokomori, Syunsuke Fujita, Magane Aoki, Yoshinobu Nakayama, Hiroyoshi Funato
  • Patent number: 5195071
    Abstract: An optical head for detecting defocuses of a target comprises a waveguide element having a substrate and an optical waveguide layer formed thereon. An optical coupler and one or more pairs of photodetectors are integrated with the waveguide layer. Light reflected back from the target is coupled with the waveguide layer through the coupler and then waveguided toward the photodetectors while being collected. Each of the photodetectors can detect the waveguided light so that a focus error signal can be obtained from the difference of the outputs of the photodetectors. The photodetectors of each pair are spaced from each other in a propagation direction of the waveguide layer so that one of the photodetectors can block off a fraction of the waveguided light from the other photodetector when the target surface is in focus.
    Type: Grant
    Filed: February 13, 1990
    Date of Patent: March 16, 1993
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroyoshi Funato, Shigeyoshi Misawa
  • Patent number: 5175642
    Abstract: A light source unit comprises a laser unit for emitting a laser beam; a deflection element for deflecting the laser beam emitted from the laser unit and for outputting a deflected laser beam, a deflection angle of the deflected laser beam being controlled by a control signal supplied from an external controller to the deflection element; and a shading member for partly or entirely shading the deflected laser beam output from the deflection element, a spot size of a laser beam passing through the shading member being changed in accordance with the deflection angle of the deflected laser beam. The light source unit outputs the laser beam passing through the shading element.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: December 29, 1992
    Assignee: Ricoh Company, Ltd.
    Inventor: Hiroyoshi Funato
  • Patent number: 5124835
    Abstract: An optical scanning apparatus for scanning a beam of light from a light source over a target surface by a scanning mechanism to form an image on the target surface. The optical scanning apparatus includes an electro-optic lens provided in an optical path between the light source and the scanning mechanism, a plurality of electrodes being provided on top and bottom surfaces of the electro-optic lens for producing an electric field in a direction perpendicular to the direction of the optical path, and a voltage applying unit being connected to the electrodes. The electro-optic lens is made from an electro-optic medium, and has an ingress surface and and egress surface which are ground to exhibit an adequate electro-optic effect. The beam is cast on the target surface to produce a dot having an enlarged diameter in the vertical scanning direction and in the horizontal scanning direction due to the electro-optic effect of the electro-optic medium when the electric field is produced within the electro-optic lens.
    Type: Grant
    Filed: June 20, 1990
    Date of Patent: June 23, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Takashi Shibaguchi, Hiroyoshi Funato
  • Patent number: 5119452
    Abstract: A high efficiency prism coupling device that comprises a substrate, an optical waveguide layer disposed on the substrate, a gap adjuster layer disposed on the waveguide layer and a prism secured to the gap adjuster layer through a dielectric adhesive agent. The gap adjuster layer has a refractive index which is lower than that of the waveguide layer. The gap adjuster layer has a recess formed therein for guiding an incident beam to the waveguide layer through a bottom portion thereof. The adhesive agent is disposed in and around the recess and has a refractive index which is higher than that of the waveguide layer. The prism is made from a dielectric material and disposed above the recess of the gap adjuster layer through the adhesive agent. The prism has a refractive index which is higher than that of the waveguide layer. The incident beam is introduced from outside through the prism, the adhesive agent and the bottom portion of the recess to the waveguide layer.
    Type: Grant
    Filed: June 7, 1990
    Date of Patent: June 2, 1992
    Assignee: Ricoh Company, Ltd.
    Inventors: Kiyoshi Yokomori, Yoshinobu Nakayama, Shigeyoshi Misawa, Tami Isobe, Syunsuke Fujita, Hiroyoshi Funato, Magane Aoki
  • Patent number: 5079415
    Abstract: An apparatus for converting optical information into an electrical information signal includes a plurality of one-dimensional conversion arrays arranged in parallel form. Each one-dimensional conversion array has first and second photoelectric conversion structures integrally formed. The first photoelectric conversion structure has photoelectric conversion elements each having a light receiving surface onto which an information light is projected. The second photoelectric conversion structure has photoelectric conversion elements each having a sweep light receiving surface onto which a sweep light is projected. The sweep light has a cross section which simultaneously scans the sweep light receiving surface of one of the photoelectric conversion elements included in each of the one-dimensional conversion arrays.
    Type: Grant
    Filed: April 2, 1990
    Date of Patent: January 7, 1992
    Assignees: Ricoh Company, Ltd., Agency of Industrial Science & Technology
    Inventors: Yutaka Hayashi, Hiroyoshi Funato, Iwao Hamaguchi, Shunsuke Fujita