Patents by Inventor Yuzuru Tanabe

Yuzuru Tanabe 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: 7534370
    Abstract: To provide optical elements such as a phase plate suitably used in a broadband range and a polarizing diffraction element excellent in diffraction efficiency, a polymerizable liquid crystal composition to be used for them, and an optical head device using them.
    Type: Grant
    Filed: October 15, 2007
    Date of Patent: May 19, 2009
    Assignee: Asahi Glass Company, Limited
    Inventors: Kara Yoshida, Tomoki Gunjima, Nobuhiko Takeshita, Yuzuru Tanabe, Hiroki Hotaka, Hiromasa Sato
  • Patent number: 7388822
    Abstract: A liquid crystal lens element having a lens function is provided, which is small sized without having moving part, and which can stably carry out correction of spherical aberration containing a power component corresponding to focal point change of incident light.
    Type: Grant
    Filed: August 3, 2006
    Date of Patent: June 17, 2008
    Assignee: Asahi Glass Company, Limited
    Inventors: Yoshiharu Ooi, Hiromasa Sato, Ryuichiro Shimizu, Takuji Nomura, Yuzuru Tanabe, Mitsuo Oosawa
  • Publication number: 20080048149
    Abstract: To provide optical elements such as a phase plate suitably used in a broadband range and a polarizing diffraction element excellent in diffraction efficiency, a polymerizable liquid crystal composition to be used for them, and an optical head device using them.
    Type: Application
    Filed: October 15, 2007
    Publication date: February 28, 2008
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Kara YOSHIDA, Tomoki GUNJIMA, Nobuhiko TAKESHITA, Yuzuru TANABE, Hiroki HOTAKA, Hiromasa SATO
  • Publication number: 20070251270
    Abstract: A method for producing a glass substrate for a magnetic disk by polishing a circular glass plate, which comprises a step of polishing the principal plane of the circular glass plate by using a slurry containing a CeO2 crystal powder, the CeO2 crystal powder being obtained in such a manner that a melt containing CeO2 is quenched to obtain an amorphous material, and the amorphous material is subjected to heat treatment to obtain a CeO2 crystals-precipitated amorphous material, which is subjected to acid treatment to separate and extract the CeO2 crystal powder from the CeO2 crystals-precipitated amorphous material.
    Type: Application
    Filed: April 25, 2007
    Publication date: November 1, 2007
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Katsuaki Miyatani, Osamu Miyahara, Yuzuru Tanabe, Hiroshi Usui, Yoshihisa Beppu, Kazuo Sunahara, Mitsuru Horie, Satoshi Kashiwabara, Tomohiro Sakai, Yoshinori Kon, Iori Yoshida
  • Publication number: 20070183293
    Abstract: A liquid crystal lens element capable of finely adjusting focal length according to the magnitude of applied voltage, and an optical head device employing such a liquid crystal lens element, are provided. On one surface of a transparent substrate 511, a transparent electrode 513 and a concave-convex portion 517 made of a transparent material having a cross section shape approximated by a saw-tooth shape, are formed so as to constitute a plurality of annular portions, and on one surface of a transparent substrate 512, a transparent electrode 514 is formed. The transparent electrodes 513 and 514 constitute annular divided electrode segments, and division positions of the annular electrode segments are made to be agree with division positions of annular portions of the saw-tooth-shaped concave-convex portion 517 of the transparent substrate 511.
    Type: Application
    Filed: February 2, 2007
    Publication date: August 9, 2007
    Applicant: ASAHI GLASS CO., LTD.
    Inventors: Kouichi MURATA, Takuji Nomura, Mitsuo Oosawa, Yoshiharu Ooi, Yuzuru Tanabe
  • Publication number: 20070146625
    Abstract: A liquid crystal lens element is provided, which can realize a small sized element having no moving part, and which has a lens function of switching the focal length among multiple focal lengths of at least 3 types according to an applied voltage.
    Type: Application
    Filed: October 30, 2006
    Publication date: June 28, 2007
    Applicant: ASAHI GLASS COMPANY LIMITED
    Inventors: Yoshiharu Ooi, Yuzuru Tanabe, Hiromasa Sato, Takuji Nomura, Ryuichiro Shimizu
  • Publication number: 20070127348
    Abstract: A liquid crystal lens element is provided, which does not produce change of transmission wavefront regardless of polarization state of incident light when it is off-state at a time of no voltage application, and which exhibits concave lens function for extraordinarily polarized incident light when it is on-state at a time of voltage application.
    Type: Application
    Filed: January 19, 2007
    Publication date: June 7, 2007
    Applicant: ASAHI GLASS COMPANY LIMITED
    Inventors: Yoshiharu Ooi, Takuji Nomura, Toshimasa Kakiuchi, Mitsuo Oosawa, Yuzuru Tanabe
  • Publication number: 20060280100
    Abstract: A liquid crystal lens element having a lens function is provided, which is small sized without having moving part, and which can stably carry out correction of spherical aberration containing a power component corresponding to focal point change of incident light.
    Type: Application
    Filed: August 3, 2006
    Publication date: December 14, 2006
    Applicant: ASAHI GLASS COMPANY LIMITED
    Inventors: Yoshiharu Ooi, Hiromasa Sato, Ryuichiro Shimizu, Takuji Nomura, Yuzuru Tanabe, Mitsuo Oosawa
  • Publication number: 20060090024
    Abstract: A single bus apparatus enables the simultaneous execution of both high-speed data transfer, which requires real time operation, and low-speed data transfer. At least one of slaves I/F 22-0, 22-1, . . . that control slave devices SV0-SV3 upon the request from master devices MS0-MS3 connected to interconnection bus BS via master I/Fs 21-0 through 21-3 has a constitution made of multiport slave I/F 23 corresponding to a multi-access function that allows simultaneous access from plural master devices MS0-MS3.
    Type: Application
    Filed: October 24, 2005
    Publication date: April 27, 2006
    Inventor: Yuzuru Tanabe
  • Patent number: 6917576
    Abstract: An adhesive is coated on at least one surface of a thin film of organic material having birefringent properties and a phase-difference producing function, and a fixing substrate having transmitting or reflecting properties is bonded to the thin film of organic material by the adhesive, wherein materials satisfying relations of E1<E2 and E3<E2 where E1 is the linear expansion coefficient of the thin film of organic material, E2 is the linear expansion coefficient of the adhesive and E3 is the linear expansion coefficient of the fixing substrate, and the glass transition temperature of the thin film of organic material being 150° or more, are selected.
    Type: Grant
    Filed: March 31, 2003
    Date of Patent: July 12, 2005
    Assignee: Asahi Glass Company, Limited
    Inventors: Takehiko Nishiyama, Naomitsu Umemura, Hiromasa Sato, Masahiro Murakawa, Yoshiharu Ooi, Yuzuru Tanabe
  • Publication number: 20030174631
    Abstract: An adhesive is coated on at least one surface of a thin film of organic material having birefringent properties and a phase-difference producing function, and a fixing substrate having transmitting or reflecting properties is bonded to the thin film of organic material by the adhesive, wherein materials satisfying relations of E1<E2 and E3<E2 where E1 is the linear expansion coefficient of the thin film of organic material, E2 is the linear expansion coefficient of the adhesive and E3 is the linear expansion coefficient of the fixing substrate, and the glass transition temperature of the thin film of organic material being 150° or more, are selected.
    Type: Application
    Filed: March 31, 2003
    Publication date: September 18, 2003
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Takehiko Nishiyama, Naomitsu Umemura, Hiromasa Sato, Masahiro Murakawa, Yoshiharu Ooi, Yuzuru Tanabe
  • Publication number: 20030123371
    Abstract: An adhesive is coated on at least one surface of a thin film of organic material having birefringent properties and a phase-difference producing function, and a fixing substrate having transmitting or reflecting properties is bonded to the thin film of organic material by the adhesive, wherein materials satisfying relations of E1<E2 and E3<E2 where E1 is the linear expansion coefficient of the thin film of organic material, E2 is the linear expansion coefficient of the adhesive and E3 is the linear expansion coefficient of the fixing substrate, and the glass transition temperature of the thin film of organic material being 150° or more, are selected.
    Type: Application
    Filed: November 19, 2002
    Publication date: July 3, 2003
    Applicant: ASAHI GLASS COMPANY, LIMITED
    Inventors: Takehiko Nishiyama, Naomitsu Umemura, Hiromasa Sato, Masahiro Murakawa, Yoshiharu Ooi, Yuzuru Tanabe
  • Patent number: 6580674
    Abstract: An adhesive is coated on at least one surface of a thin film of organic material having birefringent properties and a phase-difference producing function, and a fixing substrate having transmitting or reflecting properties is bonded to the thin film of organic material by the adhesive, wherein materials satisfying relations of E1<E2 and E3<E2 where E1 is the linear expansion coefficient of the thin film of organic material, E2 is the linear expansion coefficient of the adhesive and E3 is the linear expansion coefficient of the fixing substrate, and the glass transition temperature of the thin film of organic material being 150° or more, are selected.
    Type: Grant
    Filed: May 22, 2001
    Date of Patent: June 17, 2003
    Assignee: Asahi Glass Company, Limited
    Inventors: Takehiko Nishiyama, Naomitsu Umemura, Hiromasa Sato, Masahiro Murakawa, Yoshiharu Ooi, Yuzuru Tanabe
  • Publication number: 20010030732
    Abstract: An optically anisotropic diffraction grating for an optical read/write head, comprising optically isotropic polymer liquid crystal held between two transparent base plates. Gratings of different refractive indexes are formed by periodically changing the orientation of the polymer liquid crystal of the diffraction grating. This enables a high light-utilization efficiency and a high reliability to be obtained.
    Type: Application
    Filed: June 13, 2001
    Publication date: October 18, 2001
    Applicant: Asahi Glass Company, Ltd.
    Inventors: Yuzuru Tanabe, Tomoki Gunjima, Hiromasa Sato, Hiroki Hotaka
  • Patent number: 6304312
    Abstract: As an optically anisotropic diffraction grating in an optical head for reading and/or writing of an optically recording medium, optically anisotropic diffraction grating which comprises an optically anisotropic polymer liquid crystal sandwiched between two transparent substrates are used. The optically anisotropic polymer liquid crystal can have an alignment direction periodically changed to form a grating of different refractive indices, obtaining a high-utilization efficiency by light ray and a high degree of reliability.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: October 16, 2001
    Assignee: Asahi Glass Company Ltd.
    Inventors: Yuzuru Tanabe, Tomoki Gunjima, Hiromasa Sato, Hiroki Hotaka
  • Patent number: 6271966
    Abstract: An object is to provide an optical head device whereby the light utilization efficiency can be increased and which can be produced at a low cost. A glass substrate 1 having projections and recesses 2 formed by patterning a SiON type transparent thin film on its inner surface by dry etching, and a second glass substrate 3 having a polyimide film 4 formed as an alignment film on its inner surface, are laminated with a space, the periphery is sealed by a sealing material made of an epoxy resin 5, and liquid crystal 6 is injected under vacuum into the interior to form an optically anisotropic diffraction grating. On the outer surface of this second glass substrate 3, a quarter-wave film 7 is laminated, and a third glass substrate 9 is bonded by a photopolymer 8 to obtain a diffracting element 10. This diffracting element 10 is disposed between a light source and an optical recording medium to obtain an optical head device.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: August 7, 2001
    Assignee: Asahi Glass Company Ltd.
    Inventors: Yuzuru Tanabe, Tomoki Gunjima, Hiromasa Sato, Hiroki Hotaka
  • Patent number: 6180028
    Abstract: High molecular liquid crystal obtained by photopolymerizing a liquid crystal composition which comprises CH2═CHCOO—X—OC6H4—C6H4CN (X is an alkylene group) and CH2═CHCOOC6H4—C6H4CN. An optical element which is a polarized hologram element made by using the high molecular liquid crystal and an optical head having the polarized hologram element as a beam splitter.
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: January 30, 2001
    Assignee: Asahi Glass Company Ltd.
    Inventors: Hiroki Hotaka, Tomoki Gunjima, Mitsuru Kurosawa, Hiromasa Sato, Yuzuru Tanabe
  • Patent number: 6118586
    Abstract: An object is to provide an optical head device whereby the light utilization efficiency can be increased and which can be produced at a low cost. A glass substrate 1 having projections and recesses 2 formed by patterning a SiON type transparent thin film on its inner surface by dry etching, and a second glass substrate 3 having a polyimide film 4 formed as an alignment film on its inner surface, are laminated with a space, the periphery is sealed by a sealing material made of an epoxy resin 5, and liquid crystal 6 is injected under vacuum into the interior to form an optically anisotropic diffraction grating. On the outer surface of this second glass substrate 3, a quarter-wave film 7 is laminated, and a third glass substrate 9 is bonded by a photopolymer 8 to obtain a diffracting element 10. This diffracting element 10 is disposed between a light source and an optical recording medium to obtain an optical head device.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: September 12, 2000
    Assignee: Asahi Glass Company Ltd.
    Inventors: Yuzuru Tanabe, Tomoki Gunjima, Hiromasa Sato, Hiroki Hotaka
  • Patent number: 5274652
    Abstract: A harmonic wave generator comprises a semiconductor laser for generating a fundamental wave and a KNbO.sub.3 crystal which transforms the fundamental wave to a harmonic wave, wherein the KNbO.sub.3 crystal is provided with electrodes for applying an electric field to a pair of opposing surfaces of the crystal.
    Type: Grant
    Filed: April 12, 1993
    Date of Patent: December 28, 1993
    Assignee: Asahi Glass Company Ltd.
    Inventors: Tadanori Senoh, Yuzuru Tanabe, Motoichi Ohtsu
  • Patent number: 5119361
    Abstract: An optical information readout system including a record medium having a record layer capable of storing information and of reading the same optically, a resonating mirror arranged in substantially parallel to and apart at a predetermined distance from the record medium, a laser medium arranged between the record medium and the resonating mirror, a light source for pumping the laser medium, and a detector for detecting changes in a laser resonance, wherein the information recorded in the record medium is read by utilizing the surface of the recording medium as the other resonating mirror of the laser resonator and by detecting the changes of laser resonance resulted from the changes of the record medium surface by the detector.
    Type: Grant
    Filed: September 27, 1989
    Date of Patent: June 2, 1992
    Assignee: Asahi Glass Company Ltd.
    Inventor: Yuzuru Tanabe