Patents by Inventor Iwao Ohwada

Iwao Ohwada 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: 7176609
    Abstract: An electron emitter has an emitter made of a dielectric material, and an upper electrode and a lower electrode to which a drive voltage is applied to emit electrons. The upper electrode is formed on a first surface of the substance serving as the emitter, and the lower electrode is formed on a second surface of the substance serving as the emitter. The upper electrode has a plurality of through regions through which the emitter is exposed. The upper electrode has a surface which faces the emitter in peripheral portions of the through regions and which is spaced from the emitter.
    Type: Grant
    Filed: December 8, 2003
    Date of Patent: February 13, 2007
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Patent number: 7129642
    Abstract: An electron emitter has an emitter section formed on a substrate, and a cathode electrode and an anode electrode formed on a same surface of the emitter section. A slit is formed between the cathode electrode and the anode electrode. A drive voltage from a pulse generation source is applied between the cathode electrode and the anode electrode, and the anode electrode is connected to the ground. A collector electrode is provided above the emitter section at a position facing the slit. The collector electrode is connected to a bias voltage source through a resistor. The emitter section is made of a piezoelectric material.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: October 31, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20060214556
    Abstract: A light source has a transparent substrate, a fixed substrate disposed in facing relation to the transparent substrate, at least one electron emitter disposed on the fixed substrate, a phosphor layer disposed on a surface of the transparent substrate which confronts the fixed substrate, and a trajectory deflector for deflecting the trajectory of a pulsed electron flow intermittently emitted from the electron emitter. The pulsed electron flow is deflected by the trajectory deflector to two-dimensionally scan a position of the phosphor layer which is irradiated with the pulsed electron flow for thereby spreading the pulsed electron flow.
    Type: Application
    Filed: March 20, 2006
    Publication date: September 28, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Natsumi Shimogawa, Tetsuyuki Kameji, Naoki Goto, Isao Shikata
  • Publication number: 20060214557
    Abstract: A light source has a transparent substrate, a fixed substrate disposed in facing relation to the transparent substrate, and a plurality of electron emitters disposed on a principal surface of the fixed substrate. A light reflecting film is disposed on a portion of the principal surface of the fixed substrate which is free of the electron emitters. An anode electrode in the form of a transparent electrode is disposed on a substantially entire reverse side of the transparent substrate. Phosphor layers are disposed on the anode electrode at respective positions facing the electron emitters.
    Type: Application
    Filed: March 16, 2006
    Publication date: September 28, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Natsumi Shimogawa, Tetsuyuki Kameji, Naoki Goto, Isao Shikata
  • Patent number: 7109962
    Abstract: A display device has drive circuits each having a logic gate for inhibiting the inputting of a data signal from a signal line when unselected and permitting the inputting of a data signal from the signal line when selected, based on a drive signal (select voltage) applied from a select line, a capacitor for holding the output of the logic gate when selected and outputting the held output as a control voltage, and a drive voltage generating circuit for generating a drive voltage for displacing the actuator based on the control voltage from the capacitor.
    Type: Grant
    Filed: March 25, 2003
    Date of Patent: September 19, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Yasuharu Kuno, Takayoshi Akao
  • Publication number: 20060192213
    Abstract: A light-emitting device includes electron emitters for planarly emitting electrons, collector electrodes disposed to face corresponding one electron emitter, and a phosphor formed near the collector electrodes. During a period when electrons are emitted from the electron emitter, a collector voltage is applied to each of the collector electrodes in the sequence. Electrons are attracted toward a region of the phosphor in the vicinity of the collector electrode to which the collector voltage is applied, and impinge on the region of the phosphor, whereby light is emitted therefrom. The remaining region of the phosphor emit afterglow.
    Type: Application
    Filed: February 23, 2006
    Publication date: August 31, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Tetsuyuki Kameji, Hirokazu Nakamura
  • Patent number: 7088049
    Abstract: An electron-emitting element includes an electric field applying portion comprising of a dielectric formed on a substrate, a first electrode formed on one surface of the electric field applying portion, a second electrode being formed on the surface of the electric filed applying portion, and a slit formed in cooperation with the first electrode.
    Type: Grant
    Filed: December 20, 2001
    Date of Patent: August 8, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Tomoya Horiuchi
  • Patent number: 7071628
    Abstract: An electronic pulse generation device has an emitter section having a plate shape, a cathode electrode formed on a front surface of the emitter section, an anode electrode formed on a back surface of the emitter section, and a pulse generation source which applies a drive voltage between the cathode electrode and the anode electrode through a resistor. The anode electrode is connected to GND through another resistor. A collector electrode is provided above the cathode electrode, and the collector electrode is coated with a phosphor layer. A bias voltage is applied to the collector electrode through another resistor.
    Type: Grant
    Filed: November 21, 2003
    Date of Patent: July 4, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20060138907
    Abstract: Heat-treating niobium pentoxide powder causes the powder to become agglutinated and bonded while phase transformation from an orthorhombic crystal to a monoclinic crystal occurs and resultantly bar-shaped c-axis-oriented niobium pentoxide particles, the longitudinal direction of which is identical to the c axis direction, are formed. A slurry is produced by mixing the c-axis-oriented niobium pentioxide particles with lithium carbonate and a binder and is molded as a tape by a doctor blade method to form a sheet-shaped compact. By so doing, bar-shaped or columnar c-axis oriented niobium pentoxide particles are aligned in the direction of forming the tape and in the meantime a compact filled with lithium carbonate is produced. By heating the compact, a dielectric layer including a c-axis-oriented lithium niobate polycrystalline material is produced.
    Type: Application
    Filed: December 13, 2005
    Publication date: June 29, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Takaaki Koizumi, Hirofumi Yamaguchi, Iwao Ohwada, Tsutomu Nanataki
  • Patent number: 7067970
    Abstract: A light emission device has an emitter made of a dielectric material, a cathode electrode disposed on a surface of the emitter, an anode electrode disposed on a reverse surface of the emitter, and a pulse generation source for applying a drive voltage between the cathode electrode and the anode electrode through a resistor. A fluorescent body is disposed on the surface of the emitter out of contact with the cathode, but as closely to the cathode electrode as possible.
    Type: Grant
    Filed: August 25, 2003
    Date of Patent: June 27, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20060132024
    Abstract: An electron-emitting apparatus includes an emitter section made of a dielectric material, lower electrodes, upper electrodes having micro through holes, insulating layers disposed on the upper surface of the emitter section and between the adjacent upper electrodes, and focusing electrodes to which a predetermine potential is applied and which are disposed on the insulating layers. The electron-emitting apparatus applies a negative potential to the upper electrode to accumulate electrons in the emitter section and then applies a positive potential to the upper electrode. As a result, the polarization of the emitter section is reversed, and the accumulated electrons are emitted through the micro through holes in the upper electrodes by Coulomb repulsion. Owing to electric fields generated by the focusing electrodes, the emitted electrons travel in the upward direction of the upper electrode without spreading into a shape of a cone.
    Type: Application
    Filed: September 12, 2005
    Publication date: June 22, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao, Hirokazu Nakamura
  • Publication number: 20060132052
    Abstract: An electron-emitting apparatus includes an electron-emitting element having a lower electrode, an emitter section having a dielectric material, and a plurality of upper electrodes having micro through holes, and a drive voltage applying circuit having a circuit for applying a drive voltage Vin between the lower electrode and the upper electrode. The drive voltage applying circuit applies a drive voltage between the lower electrode and the upper electrode to set an element voltage Vka, which is a potential of the upper electrode relative to a potential of the lower electrode, at a negative voltage for a charge accumulation period Td so as to accumulate electrons in the emitter section, and to set the element voltage Vka at a predetermined positive voltage for an electron emission period Th so as to emit electrons from the emitter section.
    Type: Application
    Filed: September 16, 2005
    Publication date: June 22, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Takayoshi Akao, Naoki Goto, Tomohiko Sugiyama
  • Publication number: 20060118827
    Abstract: An electron emitting apparatus includes a lower electrode, an emitter section made of a dielectric material, a plurality of upper electrodes having micro through holes, and a collector electrode opposing the upper electrodes. In this electron-emitting apparatus, electrons are accumulated in the emitter section by controlling the potential difference (drive voltage) between the lower and upper electrodes with respect to the potential of the lower electrode to a negative predetermined voltage. At this time, the collector electrode of the electron-emitting apparatus is grounded. Thus, unnecessary electron-emitting is suppressed. Subsequently, the drive voltage is changed to a positive predetermined voltage. As a result, polarization reversal occurs in the emitter section, and accumulated electros are emitted through the micro through holes in the upper electrodes by Coulomb repulsion. At this time, a positive voltage Vc is applied to the collector electrode to give large energy to accelerate the electrons.
    Type: Application
    Filed: September 27, 2005
    Publication date: June 8, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Takayoshi Akao, Tetsuyuki Kameji, Hirokazu Nakamura
  • Publication number: 20060113608
    Abstract: An electron-emitting device includes an emitter section composed of a dielectric material, a lower electrode disposed on the lower side of the emitter section, and an upper electrode disposed on the upper side of the emitter section so as to be opposed to the lower electrode with the emitter section therebetween, electrons being emitted from the emitter section through the upper electrode by the application of a drive voltage between the lower electrode and the upper electrode, wherein the upper electrode is provided with a plurality of through-holes which expose the emitter section and which have an average diameter of 10 nm or more and less than 100 nm, and a peripheral portion of each through-hole facing the emitter section is separated at a predetermined distance from the emitter section.
    Type: Application
    Filed: November 29, 2005
    Publication date: June 1, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Masao Takahashi, Takayoshi Akao, Shuichi Ozawa, Kei Kosaka
  • Publication number: 20060082318
    Abstract: An electron-emitting element has an electron emission unit including a lower electrode, an emitter section composed of a dielectric material, and an upper electrode having a plurality of micro through holes; and a power supply for applying a power supply voltage to the electron emission unit. During the period between the point at which emission of electrons accumulated in the emitter section is started and the point at which the electron emission is completed, the power supply generates a first power supply voltage, whose absolute value changes with forming a sinusoidal wave so that the potential of the upper electrode is higher than the potential of the lower electrode.
    Type: Application
    Filed: September 27, 2005
    Publication date: April 20, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Takayoshi Akao, Tetsuyuki Kameji, Hirokazu Nakamura
  • Publication number: 20060082317
    Abstract: An electron-emitting apparatus includes an element having a lower electrode, an emitter section composed of a dielectric material, and an upper electrode having a plurality of micro through holes: and a drive voltage applying circuit having a power supply and a circuit that applies a voltage generated by the power supply between the lower electrode and the upper electrode. In order to emit electrons accumulated in the emitter section, the power supply generates a voltage gradually increasing from a first voltage to a second voltage. In order to accumulate electrons In the emitter section, the power supply generates a voltage gradually decreasing from the second voltage to the first voltage. A rapid change in element voltage and excessive element current can thereby be avoided, and unnecessary electron emission can be prevented.
    Type: Application
    Filed: September 26, 2005
    Publication date: April 20, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Takayoshi Akao, Tetsuyuki Kameji, Hirokazu Nakamura
  • Patent number: 7006061
    Abstract: A display device has first row select lines for selecting rows of picture elements, picture element signal lines for supplying picture element signals to picture elements which are selected, a drive unit having drive circuits arrayed at respective picture elements each for driving the corresponding actuator in response to a picture element signal, and a selector unit for selecting the actuators corresponding to selected picture elements. Each of the drive circuits has a drives potential generating circuit for applying a drive potential based on a signal from a picture element signal line to upper electrodes of actuators. The selector unit has selector circuits for applying a select potential to lower electrodes of the actuators corresponding to selected picture elements.
    Type: Grant
    Filed: March 24, 2003
    Date of Patent: February 28, 2006
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Yasuharu Kuno, Takayoshi Akao
  • Publication number: 20060022604
    Abstract: A light source has a rear glass substrate and a front glass substrate having a plate surface disposed in facing relation to a principal surface of the rear glass substrate. The plate surface of the front glass substrate is coated with a phosphor. A two-dimensional array of electron emitters is disposed on the principal surface of the rear glass substrate. A space defined between the rear glass substrate and the front glass substrate is filled with a gas. The gas may be an Hg (mercury) gas or an Xe (xenon) gas.
    Type: Application
    Filed: March 17, 2005
    Publication date: February 2, 2006
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20050280346
    Abstract: During each of frame periods, an image including gradation information is displayed at once on a display screen. Electrons are emitted in a second stage from all the pixels, independent of row scanning, separately from a first stage based on the row scanning. A display has a plurality of electron emitters arrayed in association with a plurality of pixels, and the image is displayed by electrons emitted from electron emitters. In each of the electron emitters, electrons are emitted from a first electrode toward an emitter to charge the emitter in the first stage, and the electrons are emitted from the emitter in the second stage.
    Type: Application
    Filed: June 3, 2005
    Publication date: December 22, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Patent number: 6975074
    Abstract: An electron emitter has an emitter section having a plate shape, a cathode electrode formed on a front surface of the emitter section, and an anode electrode formed on a back surface of the emitter section. A drive voltage from a pulse generation source is applied between the cathode electrode and the anode electrode through a resistor. The anode electrode is connected to GND (ground) through another resistor. A collector electrode is provided above the cathode electrode, and the collector electrode is coated with a fluorescent layer. A bias voltage is applied to the collector electrode through another resistor.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: December 13, 2005
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada