Patents by Inventor Masatoshi Shiiki

Masatoshi Shiiki 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: 7138965
    Abstract: The present invention provides a plasma display device, a luminescent device, and an image display system each having an excellent moving-image quality, a long lifetime, and high performance. The plasma display device has a plasma display panel having at least a pair of substrates, a discharge gas space formed between the pair of substrates, electrodes formed on the respective opposing surfaces of the substrates, and a phosphor layer formed on the surface of one of the pair of substrates in contact with the discharge gas space and a driver circuit for driving the panel via the electrodes. In the plasma display device, the decay time ( 1/10 decay time) of light generated from each of the phosphor layers for providing red, green, and blue emission which compose the phosphor layer is not more than 8 ms.
    Type: Grant
    Filed: October 30, 2002
    Date of Patent: November 21, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Shiiki, Teruki Suzuki, Choichiro Okazaki
  • Publication number: 20060208998
    Abstract: A liquid crystal display including a blink backlight system light source and a liquid crystal panel for adjusting the amount of light transmitted from the light source. The light source is made of a plurality of light emitting tubes each having one or more kinds of phosphors, and having a turned-on state and a turned-off state within one frame. A luminance factor area of light from each of the phosphors is substantially equal to that of light from any other phosphor in at least one of a luminance rise time when the light source changes from the turned-off state to the turned-on state and a luminance fall time when the light source changes from the turned-on state to the turned-off state.
    Type: Application
    Filed: December 16, 2002
    Publication date: September 21, 2006
    Inventors: Kenji Okishiro, Yoshinori Aono, Masaaki Komatsu, Masatoshi Shiiki
  • Patent number: 7088315
    Abstract: A plasma display device is realized which has a high set-luminous-efficacy (i.e. provides a high-brightness display image at a low power consumption) and a high light-room contrast. The luminous efficacy hs and the display discharge voltage Vs are increased by increasing the product pd in discharge, or increasing the Xe proportion aXe of the discharge. As a result the display-discharge region area ratio Ad and the display region reflectance ? can be reduced by reducing the display-electrode area Sse approximately in inverse proportion to Vs2, and thereby the set-luminous efficacy hs and the set luminance Bpons and the light-room contrast Cb are increased.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: August 8, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Keizo Suzuki, Shirun Ho, Masatoshi Shiiki, Tatsuya Miyake, Kenichi Yamamoto
  • Publication number: 20060170325
    Abstract: A liquid crystal display device by the use of such a high quality light source in order to suppress brightness distribution and chromaticity distribution of a light source. The liquid crystal display device comprises a white light source provided with a blue phosphor that emits blue light, a green phosphor that emits green light, and a red phosphor that emits red light and a liquid crystal display panel having color filters to adjust the amount of transmitted light from the white light source for every pixel and transmit any one of blue, green, and red lights for every pixel, where the red phosphor to be used is represented by a composition formula (Y1-x-y,Gdx,Euy)2O3. At this time, it is desirable that the conditions of 0.45?x?0.85 and 0.025?y?0.040 respectively are satisfied.
    Type: Application
    Filed: January 27, 2006
    Publication date: August 3, 2006
    Inventors: Kenji Okishiro, Masatoshi Shiiki
  • Patent number: 7053422
    Abstract: The present invention provides a solid state light-emissive display apparatus of high brightness and efficiency, high reliability, and of thin type, and method of manufacturing the same at low cost. Said apparatus has the luminous thin film made up by laminating or mixing crystal fine particle coated with insulator (5) of nm size and fluorescent fine particles (7) of nm size, and the lower electrode and the transparent upper electrode sandwiching said luminous thin film, wherein the electrons injected from said lower electrode are accelerated in the crystal fine particle coated with insulator layer (6) not being scattered by phonons to become high energy ballistic electrons, and form excitons (13) by colliding excitation of fluorescent fine particles. Since said fluorescent fine particles are of nm size, the exciton concentration is high, and luminescence intensity by extinction of excitons is also high.
    Type: Grant
    Filed: September 30, 2002
    Date of Patent: May 30, 2006
    Assignee: Japan Science and Technology Agency
    Inventors: Masahiko Ando, Toshikazu Shimada, Masatoshi Shiiki, Shunri Oda, Nobuyoshi Koshida
  • Publication number: 20060049757
    Abstract: A plasma display panel includes plural discharge cells and a barrier rib layer which defines the discharge cells. Each discharge cells has two opposing electrodes on front and rear substrates, respectively, for generating discharge therebetween, discharge gas and phosphor films. The barrier rib layer is fabricated as a sheet separate from the substrates, is provided with openings each forming a discharge space, and is sandwiched between the substrates. The following relationships are satisfied: 0.1?S2/S1?0.4; 100 Torr×mm?pd?400 Torr×mm; and 0.2 mm?d, where S1 is an area of a projection of a space occupied by one discharge cell onto the front substrate, S2 is an area of a portion of the front substrate for projecting light from the discharge cell, p is a pressure of the discharge gas, and d is a distance between the electrodes.
    Type: Application
    Filed: January 27, 2005
    Publication date: March 9, 2006
    Inventors: Tatsuya Miyake, Keizo Suzuki, Masatoshi Shiiki, Tsuyoshi Fujita, Seiichi Tsuchida
  • Patent number: 7005197
    Abstract: The luminance of phosphor is enhanced by forming a phosphor screen of a fluorescence generation unit by phosphor expressed by the following composition formula: (L1-a-bGdaCeb)3(Al1-cGac)5O12:Md wherein, a, b and c are each in the following ranges of 0?a?1.0, 0<b?0.1 and 0?c?1.0, M is dopant of a monovalent metal element and is included in phosphor by approximately 0<d?1000 wt-ppm. Dopant M of a monovalent metal element is at least one type of element selected from a group consisting of K, Na, Li, Cu, Ag and Au. Thus, a display using a white light of improved luminescence and having excellent characteristics can be realized.
    Type: Grant
    Filed: February 14, 2002
    Date of Patent: February 28, 2006
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Shiiki, Choichiro Okazaki, Teruki Suzuki, Shin Imamura, Masaaki Komatsu, Hiromichi Yamada
  • Publication number: 20060033860
    Abstract: An object of the present invention is to provide a moving picture displayable liquid crystal display device capable of attaining satisfactory moving picture characteristics, color reproducibility and reliability at the same time.
    Type: Application
    Filed: June 17, 2005
    Publication date: February 16, 2006
    Inventors: Kenji Okishiro, Shin Imamura, Masatoshi Shiiki
  • Publication number: 20050264161
    Abstract: A blue-emitting phosphor is optimized by controlling mole fractions typically of Mg and Si in Sr3-eMgbSi2cO8d:Eue or by further including an optimal amount of at least one additional component such as Ba or Ca. The resulting phosphor exhibits a higher brightness and a higher color purity upon excitation by ultraviolet light emitted as a result of discharge of xenon gas. The optimized phosphor is incorporated into light emitting devices such as lamps and PDPs, and further into display devices.
    Type: Application
    Filed: May 24, 2005
    Publication date: December 1, 2005
    Inventors: Hitoshi Oaku, Choichiro Okazaki, Masatoshi Shiiki
  • Publication number: 20050236987
    Abstract: A plasma display panel has plurality discharge cells disposed between a pair of opposing first and second substrates. Each of the discharge cells includes at least: at least one pair of electrodes for generating a discharge for display; a discharge gas; and a phosphor film for emitting visible light by being excited by ultraviolet light produced by the discharge of the discharge gas. Laminated members are dispersed in a plane within each of the discharge cells inside the first substrate from which visible light for display is emitted. Each of the laminated members includes a light absorption layer disposed on a side of the first substrate on which ambient light is incident and a light reflection layer disposed on a phosphor-film side of each of the laminated members.
    Type: Application
    Filed: February 23, 2005
    Publication date: October 27, 2005
    Inventors: Choichiro Okazaki, Masatoshi Shiiki, Keizo Suzuki, Kenichi Yamamoto
  • Patent number: 6876142
    Abstract: The present invention relates to a field-emission display having a faceplate formed with a phosphor layer and means irradiating an electron beam onto the phosphor layer in order to improve the characteristic of life of the device. The feature of the present invention is in the structure of a phosphor layer. The phosphor layer is expressed by a general formula: ZnS: M, Al where M is an activator of at least one of Cu, Ag and Au; and Al is a coactivator, in which the concentration of Al is higher than that of M. According to the present invention, the electrification characteristic of the phosphor is improved for lower resistance. The defect concentration of the surface of the phosphor is reduced. The filed-emission display which can realize improvement in the characteristic of life which has not been solved in the prior art can be made.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: April 5, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Komatsu, Masatoshi Shiiki, Ryo Inoue
  • Publication number: 20050012447
    Abstract: The disclosed method can improve the luminescence life of an image display device. By using a blue luminescent phosphor having the phosphor component ZnS:M, N (where M is one or more elements selected from Cu, Ag, and Au, and N is one or more elements selected from Al, Ga, In, and Cl); wherein a shoulder is observed at around 400 nm (3.10 eV) of a cathode-luminescence spectrum of a field-emission display. A phosphor of a field-emission display of the present invention has improved characteristics against deterioration by electron-beam irradiation and an excellent luminescence maintenance factor, therefore, the luminescence life characteristics of a display are improved.
    Type: Application
    Filed: June 22, 2004
    Publication date: January 20, 2005
    Inventors: Masaaki Komatsu, Masatoshi Shiiki, Ryo Inoue
  • Publication number: 20050007308
    Abstract: A plasma display device is realized which has a high set-luminous-efficacy (i.e. provides a high-brightness display image at a low power consumption) and a high light-room contrast. The luminous efficacy hs and the display discharge voltage Vs are increased by increasing the product pd in discharge, or increasing the Xe proportion aXe of the discharge. As a result the display-discharge region area ratio Ad and the display region reflectance ? can be reduced by reducing the display-electrode area Sse approximately in inverse proportion to Vs2, and thereby the set-luminous efficacy hs and the set luminance Bpons and the light-room contrast Cb are increased.
    Type: Application
    Filed: August 25, 2003
    Publication date: January 13, 2005
    Inventors: Keizo Suzuki, Shirun Ho, Masatoshi Shiiki, Tatsuya Miyake, Kenichi Yamamoto
  • Patent number: 6838825
    Abstract: A plasma display includes a display panel and a driving circuit for driving the display panel. A space for at least one color, of spaces between barrier ribs for defining discharge spaces for red, green and blue colors of the display panel is different from the spaces for other colors.
    Type: Grant
    Filed: May 28, 2002
    Date of Patent: January 4, 2005
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Shiiki, Choichiro Okazaki, Teruki Suzuki, Keizo Suzuki, Tadashi Furukawa, Masaji Ishigaki
  • Publication number: 20040257304
    Abstract: There is provided a plasma display device capable of high luminous efficacy and stable driving for displaying images at various image display load factors. The plasma display device performs the sustain discharge for a light-emission display, and is configured to apply a sustain pulse voltage between a sustain electrode pair in a respective one of the plural discharge cells to generate a sustain discharge in a respective one of the following operating modes selected based upon use of the plasma display device: (a) generating a pre-discharge and then a main discharge; (b) generating a main discharge without a pre-discharge preceding the main discharge; and (c) switching between the mode (a) and the mode (b). The sustain voltage waveforms are used which compensate for an increase in voltage drop due to an increase in discharge current when the image display load factor is excessively increased.
    Type: Application
    Filed: August 28, 2003
    Publication date: December 23, 2004
    Inventors: Kenichi Yamamoto, Keizo Suzuki, Masatoshi Shiiki, Kyoji Kariya, Tomokatsu Kishi, Tetsuya Sakamoto, Takashi Sasaki, Takayuki Shimizu
  • Publication number: 20040246408
    Abstract: The present invention provides a solid state light-emissive display apparatus of high brightness and efficiency, high reliability, and of thin type, and method of manufacturing the same at low cost.
    Type: Application
    Filed: March 25, 2004
    Publication date: December 9, 2004
    Inventors: Masahiko Ando, Toshikazu Shimida, Masatoshi Shiiki, Shunri Oda, Nobuyoshi Koshida
  • Patent number: 6791253
    Abstract: A field-emission display apparatus includes a faceplate on which a phosphor layer is formed, and a means for irradiating electron beam onto the phosphor layer and the phosphor layer is constituted by phosphors formed by mixing main phosphors with small particle phosphors, the averaged particle diameter of which is smaller than ½ of an averaged particle diameter of the main phosphors, enhancing the filing density of the phosphor layer and also enhancing both a lifetime characteristic and a luminescent characteristic of the phosphor layer.
    Type: Grant
    Filed: June 20, 2002
    Date of Patent: September 14, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Masaaki Komatsu, Masatoshi Shiiki, Shin Imamura
  • Patent number: 6762551
    Abstract: A white light source includes an ultraviolet-visible excitation light generation unit capable of generating visible light and ultraviolet light, and a fluorescence generation unit having a phosphor layer and being capable of generating visible light upon excitation by the ultraviolet light and uses, in the phosphor layer, a red light emitting phosphor represented by the following compositional formula: (Ca1−a−bSraEub)S:Mc, wherein a, b and c satisfy the following conditions: 0≦a<1.0, 0≦b<0.1 and 0≦c≦0.1; and M is a dopant element having absorption of excitation energy at about 350 nm to about 500 nm. The dopant element M includes rare earth elements such as Ce, Yb, Gd and Tm. By substituting part of Ca and/or Sr with Zn, the white light source can exhibit further improved performances.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: July 13, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Masatoshi Shiiki, Masaaki Komatsu, Choichiro Okazaki, Shin Imamura, Teruki Suzuki
  • Patent number: 6753099
    Abstract: The present invention provides a green emitting phosphor which includes an excess of the ordinary SiO2 component included in parent material Y2−2xSiO5 activated by Tb in terms of stoichiometric ratio. The composition of the above phosphor is represented by chemical formula: {(Y1−y−zMyGdz)1−xTbx}2(Si1−bGebO2)1+aO3 where values of x, y, z, a, and b are assigned, subject to 0<x≦1, 0≦y≦1, 0≦z≦1, 0<a≦1, and 0≦b≦1, and M is at least one element selected from a group comprising Sc, In, La, Lu, Yb, Ce, Eu, Sm, Tm, Ho, Er, and Nd. By using this phosphor, phosphors that emit light of higher luminance with less luminance degradation and are suitable for high-quality image display and imaging devices producing high-quality images are obtained.
    Type: Grant
    Filed: June 27, 2002
    Date of Patent: June 22, 2004
    Assignees: Hitachi, Ltd., Hitachi Device Engineering Co., Ltd., Kasei Optonix, Ltd.
    Inventors: Shin Imamura, Masatoshi Shiiki, Masaaki Komatsu, Hidetsugu Matsukiyo, Yoshihiro Koseki, Takashi Hase, Tsutomu Yamada
  • Patent number: 6696782
    Abstract: Green-emitting phosphor having a composition formula represented by (Y1-x-aGdxMa)3-3yTb3y(Al1-zGaz)5O12, where 0<x≦1, 0≦a<1, 0<x+a≦1, 0<y<1 and 0≦z≦1 and M is at least one of Sc, Yb and La, improves emission color of phosphors of Y3(Al, Ga)5O12:Tb series, and in case that y=0.07, z=0.4 and a=0 in the foregoing composition, color y is increased with increasing Gd concentration, when Gd concentration x is changed, and the emission color becomes clear green.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: February 24, 2004
    Assignee: Hitachi, Ltd.
    Inventors: Shin Imamura, Masatoshi Shiiki, Hiromichi Yamada, Masaaki Komatsu