Patents by Inventor Ikuo Kasuga

Ikuo Kasuga 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: 6798819
    Abstract: A deflector deflects laser light emitted from a laser light emitting device. A lens driver moves an objective lens for conversing the laser light deflected by the deflector onto an optical recording disk in a focusing direction and a tracking direction thereof. A frame member supports the laser light emitting device, the deflector and the lens driver. The deflector is positioned such that the center of an intensity distribution of the laser light is aligned with an optical axis of the objective lens.
    Type: Grant
    Filed: February 24, 2000
    Date of Patent: September 28, 2004
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventors: Tohru Hotta, Ikuo Kasuga
  • Patent number: 6584061
    Abstract: An optical system of an optical pick-up device 1 comprises a half mirror 13 and a prism 14 which serve to guide a first laser beam L1 for a CD and a second laser beam L2 for a DVD to the optical recording medium side and a common light receiving element 19. The half mirror 13 is set to have a ratio of a reflectance to a transmittance of 5:1 in the first laser beam L1 to be a P polarized light and the prism 14 is set to have a ratio of a reflectance to a transmittance of 1:3 in the first laser beam L2 having a P polarization component and an S polarization component mixed. The first laser beam for a CD can be guided to the optical recording medium without a light quantity loss. At the same time, a return light Lr can be sent in a sufficient light quantity back to the light receiving element 19 for servo signal generation. Therefore, it is possible to implement a reliable CD recording operation by using the first laser beam.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: June 24, 2003
    Assignees: Kabushiki Kaisha Sankyo Seiki Seisakusho, Kabushiki Kaisha Toshiba
    Inventors: Katsushige Yanagisawa, Tohru Hotta, Ikuo Kasuga, Satoru Kishita
  • Patent number: 6522619
    Abstract: An optical pick-up device (1) includes a laser diode (2) for recording which acts as a fixation side light source attached to an attachment portion (5) of a device frame (4) and has a great calorific value, and a laser diode (3) for reproduction which acts as an adjustment side light source held in a holder (6) fixed with an adhesive (7) in a clearance (46) provided on a side surface (45) of the device frame. Heat generated from the laser diode (2) for recording is radiated efficiently through the device frame (4), and heat generated from the laser diode (3) is also radiated efficiently through the holder (6) fixed with the adhesive (7) which is partially filled for the device frame (4) with the clearance (46) formed.
    Type: Grant
    Filed: December 4, 2000
    Date of Patent: February 18, 2003
    Assignees: Kabushiki Kaisha Sankyo Seiki Seisakusho, Toshiba Corporation
    Inventors: Katsushige Yanagisawa, Tohru Hotta, Ikuo Kasuga, Toshihiko Okina, Satoru Kishita, Hidenori Sai
  • Patent number: 6369963
    Abstract: An optical pickup apparatus has an objective lens, a lens holder that mounts the objective lens, a main frame holding the lens holder, and first and second inclination angle adjusting mechanism for adjusting angles of inclination of the objective lens. A main shaft guide frame is mounted on one side of the main frame. A main shaft mounted on the main shaft guide frame for guiding the objective lens in a radial direction of an optical disc. An auxiliary shaft guide frame is mounted on another side of the main frame. An auxiliary shaft is mounted on the auxiliary shaft guide groove to allow the objective lens to slidably move in parallel with the main shaft. The first inclination angle adjusting mechanism has a first bearing shaft for rotatably supporting the main shaft guide frame about a first axis with respect to the main frame. The main shaft defines a second axis extending generally in parallel with the main shaft and perpendicular to the first axis.
    Type: Grant
    Filed: July 6, 2000
    Date of Patent: April 9, 2002
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventors: Tohru Hotta, Ikuo Kasuga, Katsushige Yanagisawa
  • Publication number: 20010043520
    Abstract: An optical pick-up device 1 comprises a laser diode 2 for recording which acts as a fixation side light source attached to an attachment portion 5 of a device frame 4 and has a great calorific value, and a laser diode 3 for reproduction which acts as an adjustment side light source held in a holder 6 fixed with an adhesive 7 in a clearance 46 provided on a side surface 45 of the device frame. Heat generated from the laser diode 2 for recording is radiated efficiently through the device frame 4, and heat generated from the laser diode 3 is also radiated efficiently through the holder 6 fixed with the adhesive 7 which is partially filled for the device frame 4 with the clearance 46 formed.
    Type: Application
    Filed: December 4, 2000
    Publication date: November 22, 2001
    Inventors: Katsushige Yanagisawa, Tohru Hotta, Ikuo Kasuga, Toshihiko Okina, Satoru Kishita, Hidenori Sai
  • Publication number: 20010002896
    Abstract: An optical system of an optical pick-up device 1 comprises a half mirror 13 and a prism 14 which serve to guide a first laser beam L1 for a CD and a second laser beam L2 for a DVD to the optical recording medium side and a common light receiving element 19. The half mirror 13 is set to have a ratio of a reflectance to a transmittance of 5:1 in the first laser beam L1 to be a P polarized light and the prism 14 is set to have a ratio of a reflectance to a transmittance of 1:3 in the first laser beam L2 having a P polarization component and an S polarization component mixed. The first laser beam for a CD can be guided to the optical recording medium without a light quantity loss. At the same time, a return light Lr can be sent in a sufficient light quantity back to the light receiving element 19 for servo signal generation. Therefore, it is possible to implement a reliable CD recording operation by using the first laser beam.
    Type: Application
    Filed: December 4, 2000
    Publication date: June 7, 2001
    Inventors: Katsushige Yanagisawa, Tohru Hotta, Ikuo Kasuga, Satoru Kishita
  • Patent number: 6125091
    Abstract: An optical pickup apparatus comprises a first semiconductor laser, a first beam splitter which partially reflects or transmits a laser beam generated by the first semiconductor laser in a given direction, a second semiconductor laser which emits a laser beam having a different wave length from the laser beam of the first semiconductor laser, a second beam splitter which partially reflects or transmits the laser beam generated by the second semiconductor laser in a given direction, a single photodetector which receives laser beams from the first and second semiconductor lasers when the laser beams are reflected by a recording medium, and a first reflective portion which is formed on the first beam splitter. The first reflective portion partially reflects a given polarized light beam from the first semiconductor laser and transmits a polarized light beam from the second semiconductor laser beam, which differs from the given polarized light beam. A second reflective portion is formed on the second beam splitter.
    Type: Grant
    Filed: April 30, 1998
    Date of Patent: September 26, 2000
    Assignee: Sankyo Seiki Mfg Co., Ltd.
    Inventor: Ikuo Kasuga
  • Patent number: 5844881
    Abstract: An objective lens driving device includes drive coils mounted on one of a lens holder bearing an objective lens and a stationary member; magnets mounted on the other in such a manner that said drive coils are confronted with the magnets, and the lens holder is moved in a focusing direction and a tracking direction by application of current to the drive coils; and magnetic pieces arranged in magnetic circuits including the magnets, so that magnetic attraction forces acting on the magnetic pieces produce restoring forces two-dimensionally in the focusing direction and in the tracking direction to hold the objective lens at a neutral point. The magnetic pieces are so arranged that, at the neutral point, the drive coils are confronted straightly with the magnets.
    Type: Grant
    Filed: June 23, 1995
    Date of Patent: December 1, 1998
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventors: Ikuo Kasuga, Fumio Kobayashi, Toru Kamada, Akihiko Okumura
  • Patent number: 5761174
    Abstract: An optical pickup device includes a light source irradiating a record medium with plural light spots of light emitted therefrom, a plurality of light detecting elelments to which reflected light of the light spots are guided, respectively, to adequately synthesize and compare outputs of said light detecting elements, thereby reading information recorded in tracks of the record medium, and detecting an tracking error and a focusing error, and a hologram element which splits light emitted from the light source into plural beams is disposed in an optical path between the light source and the record medium, said hologram element is split by a split line, said split line elongating in a direction perpendicular to a track of the medium on an optical axis, and a hologram pattern having a diffraction function which is substantially directed in the track direction is disposed on at least one side of said split line, thereby differentiating diffraction conditions on both sides of said split line from each other.
    Type: Grant
    Filed: September 5, 1995
    Date of Patent: June 2, 1998
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventors: Tadashi Takeda, Yoshio Hayashi, Ikuo Kasuga, Kazuo Higashiura, Noriyuki Satoh, Hisahiro Ishihara
  • Patent number: 5599864
    Abstract: A polyarylene sulfide resin composition having an excellent fluidability and a good moldability is disclosed. The resin composition is useful as a material for an optical pick-up part which has a high reliability and a high tenacity and does not generate deviation of an optical axis with changes in environmental conditions such as temperature and humidity. The polyarylene sulfide resin composition comprises, as main components, a polyarylene sulfide resin, a fibrous filler and a particulate filler, and, optionally, a silane coupling agent and an alicyclic hydrocarbon.
    Type: Grant
    Filed: October 3, 1994
    Date of Patent: February 4, 1997
    Assignees: Kabushiki Kaisha Sankyo Seiki Seisakusho, Shikoku Chemicals Corporation
    Inventors: Shogo Ogawa, Hajime Hata, Ikuo Kasuga, Hiromasa Marumo, Masamichi Hayakawa
  • Patent number: 5541898
    Abstract: An objective lens-driving used in the optical pickup of an optical disk drive. The device comprises an objective lens holder for holding an objective lens, a sheet coil, and a counterbalance mounted on the opposite side of the objective lens. The sheet coil comprises an insulating sheet on which focusing helical coil patterns and tracking helical coil patterns are juxtaposed. The holder has sheet-holding portions of an arc-shaped cross section. The focusing and tracking coil patterns are formed on the curved surfaces of the sheet-holding portions. Focusing magnets are mounted opposite to the focusing coil patterns. Tracking magnets are mounted opposite to the tracking coil patterns.
    Type: Grant
    Filed: October 4, 1995
    Date of Patent: July 30, 1996
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventors: Ikuo Kasuga, Toru Kamada, Fumio Kobayashi, Yasuyuki Nakahara
  • Patent number: 5517362
    Abstract: An optical pickup device operates to irradiate a disk with an optical beam from a light source by an objective lens and to detect the beam reflected from the disk by a light receiving element. A frame is provided for said device having an optical element fixed therein. The frame is formed with a press-fit hole into which the light source is press-fit and fixed so as to adjust the press-fit depth, thereby adjusting alignment between the optical pickup device and the disk.
    Type: Grant
    Filed: April 20, 1994
    Date of Patent: May 14, 1996
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventors: Ikuo Kasuga, Tatuki Wade, Akira Miyamae
  • Patent number: 5496993
    Abstract: Disclosed is an optical pickup device comprising a light source for irradiating a light beam onto an object from a light source, a half mirror for introducing said light beam reflected by the object to an optical detector; and a wedge-shaped photosensitive element, disposed between said half mirror and said optical detector, for cancelling out a coma produced by said half mirror.
    Type: Grant
    Filed: July 23, 1993
    Date of Patent: March 5, 1996
    Assignee: Kabushiki Kaisha Sanko Seiki Seisakusho
    Inventor: Ikuo Kasuga
  • Patent number: 5488594
    Abstract: Disclosed is an objective actuator comprising an object lens holder for holding an object lens, the object lens holder being mounted on a support shaft in a manner that the object lens holder is slidable along and rotatable about the support shaft; a drive coil mounted on the object lens holder; first yoke provided with drive magnets, the first yoke being mounted in such manner that the drive magnets confront with the drive coil, the first yoke having a center hole which is larger in diameter than the support shaft, the first yoke and the support shaft are integrally connected by molding; and shaft holding member defined by filling a resin at the center hole of the first yoke, the shaft holding member including a base portion.
    Type: Grant
    Filed: August 24, 1993
    Date of Patent: January 30, 1996
    Assignee: K. K. Sankyo Seiki Seisakusho
    Inventors: Fumio Kobayashi, Ikuo Kasuga, Akira Miyamae
  • Patent number: 4998802
    Abstract: An objective lens driving device is disclosed, in which the objective lens is moved in the direction of the optical axis thereof by a thrusting force generated between a magnet for focusing and a driving coil for focusing to effect focusing and it is moved in the direction perpendicular to that of the optical axis thereof by another thrusting force generated between a magnet for tracking and a driving coil for tracking to effect tracking.
    Type: Grant
    Filed: May 25, 1989
    Date of Patent: March 12, 1991
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventors: Ikuo Kasuga, Toru Kamada, Fumio Kobayashi
  • Patent number: 4968874
    Abstract: An optical pickup using a parallel plane plate type beam splitter is disclosed, in which the astigmatism produced by the fact that the light beam passes through the beam splitter is compensated by means of a correcting lens having anisotropically curved surfaces.
    Type: Grant
    Filed: May 25, 1989
    Date of Patent: November 6, 1990
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventor: Ikuo Kasuga
  • Patent number: 4962999
    Abstract: An optical pick-up device is disclosed, in which a bearing member for moving it along a guiding shaft is disposed separately and independently from a base plate and the bearing member can be mounted selectively on one side surface or the rear surface of the base plate.
    Type: Grant
    Filed: September 16, 1988
    Date of Patent: October 16, 1990
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventor: Ikuo Kasuga
  • Patent number: 4664476
    Abstract: A driving apparatus for an objective lens includes an electromagnetic driving device normally holding the objective lens and its support at a neutral position. When a coil of the driving device is energized, the support may be driven so as to pivot about an axis to adjust the position of the lens.
    Type: Grant
    Filed: November 6, 1985
    Date of Patent: May 12, 1987
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventor: Ikuo Kasuga