Patents by Inventor Takamasa Yoshikawa

Takamasa Yoshikawa 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: 20230418142
    Abstract: A light source device includes: a light source unit emitting first light in a first polarization direction and second light in a second polarization direction; a polarization separation element receiving the first light and the second light; a phosphor receiving the first light transmitted through the polarization separation element; and a phase conversion element receiving the second light reflected by the polarization separation element. The polarization separation element reflects visible light having a longer wavelength than a polarization transmission wavelength region. The phosphor converts the received first light into third light having a longer wavelength than the polarization transmission wavelength region. The phase conversion element phase-converts the received second light into fourth light in the first polarization direction.
    Type: Application
    Filed: June 1, 2023
    Publication date: December 28, 2023
    Inventors: Takamasa YOSHIKAWA, Takao YAMASHITA, Nao MORISHITA
  • Patent number: 11088006
    Abstract: An electrostatic chuck includes a platform, a power feed pin, a tubular insulator, an adhesive layer, and a first primer. The platform includes an electrode. The power feed pin contacts the electrode. The tubular insulator is provided around the power feed pin. The adhesive layer bonds the platform and the tubular insulator together. The first primer is provided on a surface of the tubular insulator facing toward the adhesive layer.
    Type: Grant
    Filed: June 4, 2019
    Date of Patent: August 10, 2021
    Assignee: SHINKO ELECTRIC INDUSTRIES CO., LTD.
    Inventors: Takamasa Yoshikawa, Hiroharu Yanagisawa, Nobuyuki Iijima
  • Publication number: 20190385883
    Abstract: An electrostatic chuck includes a platform, a power feed pin, a tubular insulator, an adhesive layer, and a first primer. The platform includes an electrode. The power feed pin contacts the electrode. The tubular insulator is provided around the power feed pin. The adhesive layer bonds the platform and the tubular insulator together. The first primer is provided on a surface of the tubular insulator facing toward the adhesive layer.
    Type: Application
    Filed: June 4, 2019
    Publication date: December 19, 2019
    Inventors: Takamasa Yoshikawa, Hiroharu Yanagisawa, Nobuyuki Iijima
  • Publication number: 20120083409
    Abstract: Disclosed is a TiO2 nano particle exhibiting a strongly activated catalyst function. The TiO2 nano particle is created by a step of mixing Ti powder and metal powder M (M is Ni, Cr, Pt, Rh, Ru or Cu), a step of generating heat plasma, and a step of supplying a mixture of the titanium powder and the metal powder to the heat plasma using an inert gas as a carrier gas and supplying oxygen gas to the heat plasma. The created TiO2 nano particle is injected with a metal and/or a metal oxide MxOy (M is Ni, Cr, Pt, Rh, Ru or Cu, x=1, 2, 3 . . . and y=0, 1, 2 . . . ), thereby exhibiting high photocatalytic activity.
    Type: Application
    Filed: January 29, 2010
    Publication date: April 5, 2012
    Applicants: NATIONAL INSTITUTE FOR MATERIALS SCIENCE, PIONEER CORPORATION
    Inventors: Hideo Okuyama, Yoshio Sakka, Noriyoshi Shida, Masahiro Uda, Atsushi Watanabe, Takamasa Yoshikawa
  • Patent number: 7994698
    Abstract: An electron emitting device includes an amorphous electron supply layer, an insulating layer formed on the electron supply layer, and an electrode formed on the insulating layer. The electron emits device emitting electrons when an electric field is applied between the electron supply layer and the electrode. The electron emitting device includes a concave portion provided by notching the electrode and the insulating layer to expose the electron supply layer, and a carbon layer covering the electrode and the concave portion except for an inner portion of an exposed surface 4a of the electron supply layer and being in contact with an edge portion of the exposed surface of the electron supply layer.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: August 9, 2011
    Assignee: Pioneer Corporation
    Inventors: Ryota Tanaka, Nobuyasu Negishi, Kazuto Sakemura, Yoshiyuki Okuda, Tomonari Nakada, Atsushi Watanabe, Takamasa Yoshikawa, Kiyohide Ogasawara
  • Patent number: 7902760
    Abstract: Provided is a method of driving an electron emission apparatus that drives the apparatus including a plurality of electron emission devices each having an electron supply layer formed of silicon, a silicon-based mixture or a compound thereof, an insulator layer formed on the electron supply layer and a thin film metal electrode formed on the insulator layer. The plurality of electron emission devices are sealed and the method includes: a driving step for supplying power between the electron supply layer and the thin film metal electrode to cause electrons to be emitted from the electron emission device and a reactivating step for applying a reactivating voltage at a level equal to or higher than an applied voltage value which causes discontinuity in differential value of the device current flowing between the electron supply layer and the thin film metal electrode with respect to the applied voltage.
    Type: Grant
    Filed: June 24, 2005
    Date of Patent: March 8, 2011
    Assignee: Pioneer Corporation
    Inventors: Nobuyasu Negishi, Kazuto Sakemura, Takamasa Yoshikawa, Kiyohide Ogasawara
  • Publication number: 20090284129
    Abstract: [PROBLEMS] To provide an electron emitting layer with improved efficiency of electron emission and prevented damage of the device. [SOLVING MEANS] An electron emitting device including an amorphous electron supply layer 4, an insulating layer 5 formed on the electron supply layer 4, and an electrode 6 formed on the insulating layer 5, the electron emitting device emitting electrons when an electric field is applied between the electron supply layer 4 and the electrode 6, wherein the electron emitting device includes a concave portion 7 provided by notching the electrode 6 and the insulating layer 5 to expose the electron supply layer 4, and a carbon layer 8 covering the electrode 6 and the concave portion 7 except for an inner portion 4b of an exposed surface 4a of the electron supply layer 4 and being in contact with an edge portion 4c of the exposed surface 4a of the electron supply layer 4.
    Type: Application
    Filed: March 26, 2007
    Publication date: November 19, 2009
    Inventors: Ryota Tanaka, Nobuyasu Negishi, Kazuto Sakemura, Yoshiyuki Okuda, Tomonari Nakada, Atsushi Watanabe, Takamasa Yoshikawa, Kiyohide Ogasawara
  • Publication number: 20080211401
    Abstract: An electron emission device including a lower electrode on a near side to a substrate and an upper electrode on a far side to the substrate and an insulator layer and an electron supply layer stacked between the lower electrode and the upper electrode and emitting an electron from the upper electrode side at the time of applying a voltage between the lower electrode and the upper electrode, which includes an electron emission part provided with an opening formed by an inner wall of a stepped shape in which a thickness of the insulator layer decreases stepwise; and a carbon-containing carbon region which is connected to the upper electrode side and which is brought into contact with the insulator layer and the electron supply layer.
    Type: Application
    Filed: November 15, 2005
    Publication date: September 4, 2008
    Inventors: Tomonari Nakada, Nobuyasu Negishi, Kazuto Sakemura, Yoshiyuki Okuda, Saburo Aso, Atsushi Watanabe, Takamasa Yoshikawa, Kiyohide Ogasawara
  • Publication number: 20080203947
    Abstract: Provided is a method of driving an electron emission apparatus used in displays, imaging devices, flat-surface light sources and the like which can restrain a change with time.
    Type: Application
    Filed: June 24, 2005
    Publication date: August 28, 2008
    Inventors: Nobuyasu Negishi, Kazuto Sakemura, Takamasa Yoshikawa, Kiyohide Ogasawara
  • Patent number: 7348531
    Abstract: Disclosed is an image pickup device capable of greatly reducing delay in drive signals supplied to field emission devices, and cross-talk and the like that originate in these drive signals. The image pickup device comprises a photoelectric conversion film for receiving incident light on one side thereof; a field emission layer having an electron emitting surface apart from and facing the other side of the photoelectric conversion film, and including a plurality of electron emission devices; and a drive layer formed on a back side of the field emission layer and including a plurality of device drive circuits for supplying drive signals to each of back electrodes of the plurality of electron emission devices.
    Type: Grant
    Filed: February 9, 2005
    Date of Patent: March 25, 2008
    Assignee: Pioneer Corporation
    Inventors: Yoshiyuki Okuda, Saburo Aso, Katsumi Yoshizawa, Takamasa Yoshikawa, Hideo Satoh, Nobuyasu Negishi, Kazuto Sakemura
  • Publication number: 20070241655
    Abstract: An electron emitting device having a lower electrode on a side near to a substrate and an upper electrode on a side remote from the substrate respectively, formed of a plurality of electron emitting elements remitting electrons from a side of the upper electrode side, wherein space is formed between the electron emitting elements, and the upper electrode extends across the plurality of electron emitting elements and the space by a bridging portion of the upper electrode.
    Type: Application
    Filed: March 22, 2005
    Publication date: October 18, 2007
    Inventors: Kazuto Sakemura, Saburo Aso, Koji Hanihara, Nobuyasu Negishi, Tomonari Nakada, Takamasa Yoshikawa
  • Patent number: 7125144
    Abstract: An illumination device includes plural lamps, a prism, a first lens array, and a second lens array, wherein the first lens array is formed such that images of the lamps are formed a predetermined space apart from each other on a lens, which corresponds to a predetermined lens among plural lenses of a second lens array, by light from the lamps having passed the predetermined lens of the first lens array. All or a part of plural images formed by a lens separate from the predetermined lens of the first lens array are practically arranged among the formed images of the lamps. And the second lens array is formed such that the images formed on the second lens array are irradiated on a light-receiving surface in a predetermined relation.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: October 24, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yusaku Shimaoka, Takamasa Yoshikawa
  • Patent number: 7118227
    Abstract: An illuminating optical system for focusing a radiant light of a light source (1) onto a reflecting light valve (6) and a projection lens (7) for magnifying and projecting a reflected light from the reflecting light valve (6) onto a screen are provided, a diaphragm (31) is disposed at a substantially conjugate position of an entrance pupil of the projection lens (7) on an optical path of the illuminating optical system, the diaphragm (31) has an opening whose area is changed by a light-shielding member, and a shape of a shielded portion of the diaphragm (31) shielded by the light-shielding member is rotationally asymmetric to an optical axis (12) of the illuminating optical system. Accordingly, shielding of necessary light can be better avoided compared with a diaphragm for changing the light-shielding area in a rotationally symmetric manner, for example, a diaphragm for narrowing the opening concentrically, making it possible to improve contrast performance while minimizing brightness reduction.
    Type: Grant
    Filed: April 23, 2002
    Date of Patent: October 10, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shinya Sannohe, Hideki Ishinaga, Takamasa Yoshikawa
  • Patent number: 7095040
    Abstract: An electron-emitting device includes an electron source layer made of a metal, a metal alloy or a semiconductor, an insulating layer formed on the electron source layer and a metal thin film electrode formed on the insulating layer. Electrons are emitted upon application of an electric field between the electron source layer and the metal thin film electrode. The insulating layer has at least one island region which constitutes an electron-emitting section in which the film thickness of the insulating layer is gradually reduced. The electron-emitting device further includes a carbon region made of carbon or a carbon compound on at least one of a top, bottom and inside of the island region.
    Type: Grant
    Filed: January 4, 2001
    Date of Patent: August 22, 2006
    Assignee: Pioneer Corporation
    Inventors: Shingo Iwasaki, Takashi Yamada, Takuya Hata, Takashi Chuman, Nobuyasu Negishi, Kazuto Sakemura, Atsushi Yoshizawa, Hideo Satoh, Takamasa Yoshikawa, Kiyohide Ogasawara
  • Patent number: 7033030
    Abstract: An illuminating optical system for focusing a radiant light of a light source (1) onto a reflecting light valve (6) and a projection lens (7) for magnifying and projecting a reflected light from the reflecting light valve (6) onto a screen are provided, a diaphragm (31) is disposed at a substantially conjugate position of an entrance pupil of the projection lens (7) on an optical path of the illuminating optical system, the diaphragm (31) has an opening whose area is changed by a light-shielding member, and a shape of a shielded portion of the diaphragm (31) shielded by the light-shielding member is rotationally asymmetric to an optical axis (12) of the illuminating optical system. Accordingly, shielding of necessary light can be better avoided compared with a diaphragm for changing the light-shielding area in a rotationally symmetric manner, for example, a diaphragm for narrowing the opening concentrically, making it possible to improve contrast performance while minimizing brightness reduction.
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: April 25, 2006
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shinya Sannohe, Hideki Ishinaga, Takamasa Yoshikawa
  • Patent number: 7010939
    Abstract: In a first polishing step, or in a first half of a super precision polishing, a surface of a glass substrate is polished with a first suspension. The first suspension contains particles and a dispersion agent in which the particles are dispersed. The main ingredient of the particles is silicon dioxide (SiO2), and the average size (D50) of the particles is equal to or less than 100 nm. The dispersion medium comprises an acid solution the pH of which is equal to or less than 4. In a second polishing step, or in a latter half of the super precision polishing, the surface of the glass substrate is continuously polished with a second suspension. The second suspension contains particles and a dispersion agent in which the particles are dispersed. The main ingredient of the particles is silicon dioxide (SiO2), and the average size (D50) of the particles is equal to or less than 100 nm. The dispersion medium comprises an alkaline solution the pH of which is equal to or more than 8.5.
    Type: Grant
    Filed: June 4, 2003
    Date of Patent: March 14, 2006
    Assignee: Hoya Corporation
    Inventors: Takamasa Yoshikawa, Koichi Suzuki
  • Publication number: 20050237496
    Abstract: An illuminating optical system for focusing a radiant light of a light source (1) onto a reflecting light valve (6) and a projection lens (7) for magnifying and projecting a reflected light from the reflecting light valve (6) onto a screen are provided, a diaphragm (31) is disposed at a substantially conjugate position of an entrance pupil of the projection lens (7) on an optical path of the illuminating optical system, the diaphragm (31) has an opening whose area is changed by a light-shielding member, and a shape of a shielded portion of the diaphragm (31) shielded by the light-shielding member is rotationally asymmetric to an optical axis (12) of the illuminating optical system. Accordingly, shielding of necessary light can be better avoided compared with a diaphragm for changing the light-shielding area in a rotationally symmetric manner, for example, a diaphragm for narrowing the opening concentrically, making it possible to improve contrast performance while minimizing brightness reduction.
    Type: Application
    Filed: June 23, 2005
    Publication date: October 27, 2005
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shinya Sannohe, Hideki Ishinaga, Takamasa Yoshikawa
  • Publication number: 20050225978
    Abstract: An illumination device includes plural lamps a prism, a first lens array, and a second lens array, wherein the first lens array is formed such that images of the lamps are formed a predetermined space apart from each other on a lens, which corresponds to a predetermined lens among plural lenses of a second lens array, by light from the lamps having passed the predetermined lens of the first lens array. All or a part of plural images formed by a lens separate from the predetermined lens of the first lens array are practically arranged among the formed images of the lamps. And the second lens array is formed such that the images formed on the second lens array are irradiated on a light-receiving surface in a predetermined relation.
    Type: Application
    Filed: October 9, 2003
    Publication date: October 13, 2005
    Inventors: Yusaku Simaoka, Takamasa Yoshikawa
  • Publication number: 20050184220
    Abstract: Disclosed is an image pickup device capable of greatly reducing delay in drive signals supplied to field emission devices, and cross-talk and the like that originate in these drive signals. The image pickup device comprises a photoelectric conversion film for receiving incident light on one side thereof; a field emission layer having an electron emitting surface apart from and facing the other side of the photoelectric conversion film, and including a plurality of electron emission devices; and a drive layer formed on a back side of the field emission layer and including a plurality of device drive circuits for supplying drive signals to each of back electrodes of the plurality of electron emission devices.
    Type: Application
    Filed: February 9, 2005
    Publication date: August 25, 2005
    Applicant: Pioneer Corporation
    Inventors: Yoshiyuki Okuda, Saburo Aso, Katsumi Yoshizawa, Takamasa Yoshikawa, Hideo Satoh, Nobuyasu Negishi, Kazuto Sakemura
  • Publication number: 20050101230
    Abstract: The present invention provides a method which can simultaneously grind inner peripheral edges and outer peripheral edges of a multiplicity of glass substrates used for magnetic storage media or the like. In order to chamfer the outer edges of the glass substrates g, a multiplicity of annular glass substrates g are firstly stacked with buffer sheets 5 interposed between the glass substrates to make a glass substrate block G. Then, a first plates 1, 1 of the above described clamping jig are applied to both sides of the glass substrate block G, and a first fastening tool 3 is inserted through center holes of the first plates 1, 1 and the glass substrate block G. Next, the glass substrate block G is clamped from an inside thereof for chamfering the outer edges with a grindstone 6.
    Type: Application
    Filed: December 3, 2004
    Publication date: May 12, 2005
    Applicant: HOYA CORPORATION
    Inventors: Takamasa Yoshikawa, Koji Okuhata, Kensuke Matsuno, Takeo Watanabe