Patents by Inventor Keiichiro Yusu

Keiichiro Yusu 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: 8989525
    Abstract: According to an embodiment, a light deflecting element includes a dielectric body, a first electrode, and a second electrode. The second electrode is configured to sandwich the dielectric body with the first electrode so as to apply a voltage to the dielectric body. The second electrode includes orthogonal portions that are substantially orthogonal to an incident direction of a light beam passing through the dielectric body, parallel portions that are substantially parallel to the incident direction of the light beam. The orthogonal portions and the parallel portions are formed in an alternate manner on the light beam incident side of the dielectric body. The second electrode includes a linear sloping portion that slopes in a direction toward intersection with the incident direction of the light beam. The orthogonal portions, the parallel portions, and the linear sloping portion are formed integrally.
    Type: Grant
    Filed: December 26, 2012
    Date of Patent: March 24, 2015
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Yuuzo Kamiguchi, Katsuya Sugawara, Masahiro Kanamaru, Keiichiro Yusu, Masatoshi Sakurai
  • Publication number: 20130258452
    Abstract: According to an embodiment, a light deflecting element includes a dielectric body, a first electrode, a second electrode, and a third electrode. Each of the second electrode and third electrode is configured to sandwich the dielectric body with the first electrode. The second electrode includes an electrode having a side that lies substantially orthogonal to an incident direction of a light beam, a side that is substantially parallel to the incident direction, and a side that intersects with the incident direction. The third electrode includes an electrode having a side that is aligned with the second electrode, a side that is substantially parallel to an incident direction of the light beam, and a side that intersects with the light beam, and that slopes in an opposite to that of the side of the second electrode that intersects with the light beam.
    Type: Application
    Filed: December 28, 2012
    Publication date: October 3, 2013
    Inventors: Yuuzo KAMIGUCHI, Masahiro Kanamaru, Katsuya Sugawara, Keiichiro Yusu, Masatoshi Sakurai
  • Publication number: 20130259417
    Abstract: According to an embodiment, a light deflecting element includes a dielectric body, a first electrode, and a second electrode. The second electrode is configured to sandwich the dielectric body with the first electrode so as to apply a voltage to the dielectric body. The second electrode includes orthogonal portions that are substantially orthogonal to an incident direction of a light beam passing through the dielectric body, parallel portions that are substantially parallel to the incident direction of the light beam. The orthogonal portions and the parallel portions are formed in an alternate manner on the light beam incident side of the dielectric body. The second electrode includes a linear sloping portion that slopes in a direction toward intersection with the incident direction of the light beam. The orthogonal portions, the parallel portions, and the linear sloping portion are formed integrally.
    Type: Application
    Filed: December 26, 2012
    Publication date: October 3, 2013
    Inventors: Yuuzo Kamiguchi, Katsuya Sugawara, Masahiro Kanamaru, Keiichiro Yusu, Masatoshi Sakurai
  • Publication number: 20130077459
    Abstract: In a recording and reproducing apparatus, an optical disc is rotated in a rotating direction and an optical system focuses a laser beam on the optical disc to form a beam spot on the optical disc. The optical system is provided with a scanner which deflects the laser beam along a radial direction of the optical disc in such a manner that the beam spot follows a first scan trajectory along a first direction crossing the rotating direction and a second scan trajectory along a second direction different from the first direction. A first data track with a sequence of recording pits along the first scan trajectory is formed and arranged on the optical disc.
    Type: Application
    Filed: June 29, 2012
    Publication date: March 28, 2013
    Inventors: Yuuzo KAMIGUCHI, Masahiro KANAMARU, Katsuya SUGAWARA, Keiichiro YUSU, Masatoshi SAKURAI, Kazuki MATSUMOTO, Takehiro HIRAMATSU
  • Publication number: 20120153487
    Abstract: A substrate for electron-beam drawing, characterized by including a base layer 20, a first layer 30 formed on the base layer 20 comprising one of Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, In, Sn, Sb, La, Ce, Pr, Nd, Pm, Sm, Hf, Re, Os, Ir, Pt, Au, Pb, and Bi, a second layer 40 formed on the first layer 30 comprising one of C and B and having a film-thickness of 100 ?m to 300 ?m, and a resist layer 50 formed above the second layer 40.
    Type: Application
    Filed: February 29, 2012
    Publication date: June 21, 2012
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventor: Keiichiro Yusu
  • Patent number: 8077586
    Abstract: According to one embodiment, an optical recording head device includes a light source which outputs such a relaxation oscillation optical pulse that a full width at half maximum of a single pulse is 820 ps or less, a driving unit for driving the light source, an objective lens which converges emission light from the light source on a recording layer of a recording medium, and captures reflective light which is reflected by the recording layer of the recording medium, a distribution unit, placed between the light source and the objective lens, for distributing incident light, and a photodetection unit for receiving via the distribution unit the reflective light which is reflected by the recording layer of the recording medium, wherein a resonator length of the light source is 6560 ?m or less.
    Type: Grant
    Filed: October 23, 2008
    Date of Patent: December 13, 2011
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Kazuo Watabe, Takashi Usui, Keiichiro Yusu, Chosaku Noda, Kazuto Kuroda, Nobuaki Kaji, Masahiro Saito
  • Patent number: 7858166
    Abstract: According to one embodiment, in a phase change optical disk which has a substrate and a multi-layered including an interference film, phase change recording film, interface film, and reflecting film, and in which information is reversibly recorded in or erased from the recording film by using light, an element (e.g., Ge or Te) forming the phase change recording film has segregation or a concentration distribution in the thickness direction of the recording film from a portion in contact with the phase change recording film.
    Type: Grant
    Filed: January 31, 2007
    Date of Patent: December 28, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukasa Nakai, Noritake Oomachi, Sumio Ashida, Naomasa Nakamura, Keiichiro Yusu, Yasuhiro Satoh
  • Patent number: 7767285
    Abstract: A phase-change optical recording medium has a recording film that brings about reversible phase-change between a crystalline phase and an amorphous phase upon irradiation with light and an interface film formed in contact with at least one surface of the recording film and comprising hafnium (Hf), silicon (Si), oxygen (O) and carbon (C).
    Type: Grant
    Filed: February 22, 2007
    Date of Patent: August 3, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukasa Nakai, Sumio Ashida, Keiichiro Yusu, Takayuki Tsukamoto, Noritake Oomachi, Naomasa Nakamura, Katsutaro Ichihara
  • Patent number: 7736715
    Abstract: In a single-sided, recordable/rewritable phase change optical recording medium having one or more layers, an interface layer adjacent to a phase change optical recording film contains at least Zr (zirconium), O (oxygen), and N (nitrogen), and further contains one or both of Y (yttrium) and Nb (niobium).
    Type: Grant
    Filed: June 8, 2006
    Date of Patent: June 15, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukasa Nakai, Noritake Oomachi, Sumio Ashida, Naomasa Nakamura, Keiichiro Yusu, Yasuhiro Satoh
  • Patent number: 7643397
    Abstract: The present invention relates to an optical recording media including two or more information layers, at least one of the information layers including a writable recording film. In the optical recording media, at least one information layer has protrusions and recesses that permit tracking and at least another one information layer is substantially flat.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: January 5, 2010
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Tsukasa Nakai, Yasuaki Ootera, Sumio Ashida, Keiichiro Yusu, Nobuhisa Yoshida, Koji Takazawa, Naomasa Nakamura
  • Publication number: 20090268580
    Abstract: According to one embodiment, a pit having a shape wherein the shapes of the top of a recording mark (recording start position) and the end of the recording mark (recording end position) are symmetrical can be formed on a stamper master with high reproducibility. As a result, the noise level/jitter degree of the reproduction signal obtained by reproduction from an optical disc as a final product can be reduced, thereby manufacturing at low cost the optical disc from which a signal can be stably reproduced.
    Type: Application
    Filed: April 23, 2009
    Publication date: October 29, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Keiichiro YUSU, Masaaki MATSUMARU, Ryosuke YAMAMOTO
  • Publication number: 20090196142
    Abstract: According to one embodiment, in an information recording medium for which a phase change material is used and in which information is recorded on, reproduced from, and erased from a recording layer by light irradiation, a recrystallization width WR at a periphery of an amorphous recording mark formed on the recording layer by light irradiation, and a recording mark width WA and a track pitch TP satisfy 1.0<WR/WA<1.1 and 2/3<WA/TP<4/3.
    Type: Application
    Filed: January 29, 2009
    Publication date: August 6, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Keiichiro YUSU, Masahiro SAITO, Kazuto KURODA, Takashi USUI, Kazuo WATABE, Chosaku NODA, Nobuaki KAJI, Tsukasa NAKAI
  • Publication number: 20090196157
    Abstract: According to one embodiment, an information recording medium includes a substrate, a phase-change recording layer formed on the substrate, and a reflecting layer formed on the phase-change recording layer. The phase-change recording layer contains tellurium and antimony or bismuth as main components, has a crystallization rate of 2 to 10 ns, and forms a recording mark by changing its crystal state when irradiated with a light pulse having a half-width of 200 ps to 1 ns.
    Type: Application
    Filed: January 8, 2009
    Publication date: August 6, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Naomasa NAKAMURA, Keiichiro YUSU
  • Publication number: 20090196148
    Abstract: According to one embodiment, the invention provides a master recording apparatus and method which can form a pit having a symmetrical pit shape with excellent reproducibility. An embodiment of the invention is a master recording apparatus where a resist film on a master for an optical disk is irradiated with irradiation light from a semiconductor laser to record information on the resist film, where the resist film is formed as an inorganic resist film, and means for outputting the irradiation light from the semiconductor laser as a short pulse laser with a pulse width between 200 ps and 1 ns is provided.
    Type: Application
    Filed: January 29, 2009
    Publication date: August 6, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Keiichiro YUSU, Masahiro SAITO, Kazuto KURODA, Takashi USUI, Kazuo WATABE, Chosaku NODA, Nobuaki KAJI, Masaaki MATSUMARU, Ryosuke YAMAMOTO
  • Publication number: 20090196138
    Abstract: According to one embodiment, in one embodiment of the invention, a laser drive circuit is provided with a first current source, a second drive current source, and a third current source. The control section selectively obtains a plurality of laser light use mode of controlling the from first to third current sources to use pulse laser light accompanying relaxation oscillation, and a complex laser light use mode of using laser light where laser pulses are combined, whose starting end has an abrupt impulse change portion caused by relaxation oscillation and whose intermediate section is a flat portion with a fixed intensity.
    Type: Application
    Filed: January 9, 2009
    Publication date: August 6, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Nobuaki Kaji, Kazuo Watabe, Takashi Usui, Keiichiro Yusu, Chosaku Noda, Kazuto Kuroda, Masahiro Saito
  • Publication number: 20090141760
    Abstract: According to one embodiment, a drive control apparatus of a semiconductor laser includes a driving circuit which drives the semiconductor laser by applying pulses transiting from bias current to peak current to the semiconductor laser as laser driving current that causes relaxation oscillation of emission light intensity of the semiconductor laser, and a control circuit which controls the bias current such that the bias current has a predetermined ratio limiting fluctuation of a leading peak value of the relaxation oscillation occurring for each application of pulses relative to threshold current of the semiconductor laser. The control circuit changes the bias current to maintain the predetermined ratio relative to fluctuation of the threshold current.
    Type: Application
    Filed: October 29, 2008
    Publication date: June 4, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Masahiro Saito, Takashi Usui, Kazuo Watabe, Keiichiro Yusu, Chosaku Noda, Nobuaki Kaji, Kazuto Kuroda
  • Patent number: 7542404
    Abstract: An optical recording media has a disc substrate and two or more recording layers arranged apart from each other with a dielectric layer interposed therebetween to cause optical change simultaneously by irradiation with light, in which a first recording layer positioned near the disc substrate has a higher optical change temperature and a higher extinction coefficient compared with those of a second recording layer and a later recording layer.
    Type: Grant
    Filed: July 15, 2005
    Date of Patent: June 2, 2009
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Keiichiro Yusu, Sumio Ashida, Tsukasa Nakai, Shinichi Tatsuta, Hideki Ito
  • Publication number: 20090109816
    Abstract: According to one embodiment, a calibration section controls an LD driving section so as to carry out test writing on a recording layer of an optical disc using a light pulse having relaxation oscillation, irradiates the test-written area with a reproduction laser beam so as to detect reflected light, and determine write strategy based on the detected result. A recording process is executed on the optical disc by using the light pulse having relaxation oscillation based on the write strategy determined by the calibration section.
    Type: Application
    Filed: October 22, 2008
    Publication date: April 30, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takashi Usui, Kazuo Watabe, Keiichiro Yusu, Chosaku Noda, Kazuto Kuroda, Nobuaki Kaji, Masahiro Saito
  • Publication number: 20090109809
    Abstract: According to one embodiment, a laser drive circuit includes a photodetector which receives part of laser light emitted from a laser element to a recording medium independently of reflection laser light reflected by the recording medium, and outputs an output corresponding to the strength thereof, an integration circuit which integrates the output from the photodetector for a predetermined time, and a setting circuit which sets the intensity of a laser drive current supplied to the laser element on the basis of the output from the integration circuit.
    Type: Application
    Filed: October 24, 2008
    Publication date: April 30, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Kazuto Kuroda, Kazuo Watabe, Keiichiro Yusu, Chosaku Noda, Nobuaki Kaji, Takashi Usui, Masahiro Saito
  • Publication number: 20090109815
    Abstract: According to one embodiment, an optical disc device includes a light source portion which applies laser light to an optical disc, a drive portion which supplies a drive current to the light source portion so as to cause the light source portion to apply laser light of light pulses having relaxation oscillation, and a controller which controls the drive portion to supply a drive current so as to cause the light source portion to emit laser light of (n?1)×N (N is an integral number) light pulses having relaxation oscillation with respect to a mark with recording mark length nT (n: integral number, T: channel clock) to be recorded on the optical disc.
    Type: Application
    Filed: October 29, 2008
    Publication date: April 30, 2009
    Applicant: KABUSHIKI KAISHA TOSHIBA
    Inventors: Takashi Usui, Kazuo Watabe, Keiichiro Yusu, Chosaku Noda, Kazuto Kuroda, Nobuaki Kaji, Masahiro Saito