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).

  • Publication number: 20050269929
    Abstract: An electron emitter includes an emitter layer formed of a dielectric material, an upper electrode, and a lower electrode. A drive voltage is applied between the upper electrode and the lower electrode, for emitting electrons. The upper electrode is formed of scale-like conductive particles on the upper surface of the emitter layer and has a plurality of opening portions. The surfaces of overhanging portions of the opening portions that face the emitter layer are apart from the emitter layer. The overhanging portions each have such a cross-sectional shape as to be acutely pointed toward the inner edge of the opening portion, or the tip end of the overhanging portion, so that lines of electric force concentrate at the inner edge.
    Type: Application
    Filed: June 2, 2005
    Publication date: December 8, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Kei Sato, Nobuyuki Kobayashi, Shohei Yokoyama
  • Patent number: 6946800
    Abstract: An electron emitter has an electric field receiving member formed on a substrate, a cathode electrode formed on one surface of the electric field receiving member, and an anode electrode formed on the one surface of the electric field receiving member, with a slit defined between the cathode electrode and the anode electrode. The electric field receiving member is made of a dielectric material. The electron emitter also has a modulation circuit for modulating a pulse signal applied between the cathode electrode and the anode electrode based on a control signal supplied from a controller such as a CPU to control at least an amount of emitted electrons.
    Type: Grant
    Filed: February 25, 2003
    Date of Patent: September 20, 2005
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Nobuyuki Kokune, Tomoya Horiuchi
  • Patent number: 6937034
    Abstract: A sensor element formed of PZT is overlapped onto an actuator formed of electrostrictive elements, and both members are pinched between a rigid body that is not deformed. By impressing an alternating-current signal to the actuator, the sensor element is deformed in accordance with the amount of deformation thereof to use the thus generated electromotive force of the sensor element as a signal for the absolute value calculation.
    Type: Grant
    Filed: October 11, 2000
    Date of Patent: August 30, 2005
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Iwao Ohwada
  • Patent number: 6936972
    Abstract: An electron-emitting element is provided, including an electric field applying portion composed of a dielectric, a first electrode formed on one surface of the electric field applying portion, and a second electrode formed on the surface and forming a slit in cooperation with the first electrode, and which is formed on a substrate.
    Type: Grant
    Filed: November 1, 2002
    Date of Patent: August 30, 2005
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Tomoya Horiuchi
  • Publication number: 20050116603
    Abstract: An electron emitter 10A has an emitter 12 made of a dielectric material and an upper electrode 14 and a lower electrode 16 for being supplied with a drive voltage Va for emitting electrons. The upper electrode 14 is disposed on an upper surface of the emitter, and the lower electrode 16 is disposed on a lower surface of the emitter 12. The upper electrode 14 has a plurality of through regions 20 through which the emitter 12 is exposed. Each of the through regions 20 of the upper electrode 14 has a peripheral portion 26 having a surface facing the emitter 12 and spaced from the emitter 12.
    Type: Application
    Filed: July 29, 2004
    Publication date: June 2, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Patent number: 6897620
    Abstract: An electron emitter has an emitter section formed on a substrate, a cathode electrode formed on one surface of the emitter section, and an anode electrode formed on the same one surface of the emitter section and cooperating with the cathode electrode in providing a slit. A pulse generation source applies a drive voltage between the cathode electrode and the anode electrode. The anode electrode is connected to GND (ground). The slit has a width in the range from 0.1 ?m to 50 ?m.
    Type: Grant
    Filed: June 11, 2003
    Date of Patent: May 24, 2005
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Nobuyuki Kokune
  • Publication number: 20050104504
    Abstract: An electron emitter has an emitter made of a dielectric material and an upper electrode and a lower electrode for being supplied with a drive voltage for emitting electrons. The upper electrode is disposed on an upper surface of the emitter, and the lower electrode is disposed on a lower surface of the emitter. The upper electrode has a plurality of through regions through which the emitter is exposed. Each of the through regions of the upper electrode has a peripheral portion having a surface facing the emitter and spaced from the emitter.
    Type: Application
    Filed: September 27, 2004
    Publication date: May 19, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20050073261
    Abstract: An electron emitter includes 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 gap is formed between an outer peripheral portion of the cathode electrode and the front surface of the emitter section. The front surface of the emitter section contacts a lower surface of the outer peripheral portion to form a base end as a triple junction. The gap expands from the base end toward a tip end of the outer peripheral portion.
    Type: Application
    Filed: September 28, 2004
    Publication date: April 7, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050073232
    Abstract: An electron emitter includes an emitter element made of a dielectric material, and an upper electrode and a lower electrode. A drive voltage is applied between the upper electrode and the lower electrode for emitting electrons from the emitter element. The upper electrode is formed on an upper surface of the emitter element, and the lower electrode is formed on a lower surface of the emitter element. The emitter element is exposed through a plurality of through regions of the upper electrode. Peripheral surfaces around the through regions facing the emitter element are spaced from the emitter element.
    Type: Application
    Filed: October 3, 2003
    Publication date: April 7, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050073233
    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: Application
    Filed: December 8, 2003
    Publication date: April 7, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20050073790
    Abstract: A microdevice has an electron emitter including a memory for accumulating electric charges corresponding to an input voltage, for emitting electrons corresponding to the electric charges accumulated in said memory; and an amplifier connected to a power supply and including a collector electrode for capturing the electrons emitted from the electron emitter. The atmosphere between at least the electron emitter and the collector electrode is a vacuum. When the electrons emitted from the electron emitter are captured by the collector electrode of the amplifier, a collector current flows between the collector electrode and the electron emitter to amplify the input voltage.
    Type: Application
    Filed: September 28, 2004
    Publication date: April 7, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050073234
    Abstract: An electron emitter has an emitter made of a dielectric material and an upper electrode and a lower electrode for being supplied with a drive voltage for emitting electrons. The upper electrode is disposed on an upper surface of the emitter, and the lower electrode is disposed on a lower surface of the emitter. The upper electrode has a plurality of through regions through which the emitter is exposed. Each of the through regions of the upper electrode has a peripheral portion having a surface facing the emitter and spaced from the emitter.
    Type: Application
    Filed: June 25, 2004
    Publication date: April 7, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20050073235
    Abstract: An electron emitter includes a lower electrode formed on a glass substrate, an emitter section made of dielectric film formed on the lower electrode, and an upper electrode formed on the emitter section. A drive voltage for electron emission is applied between the upper electrode and the lower electrode. At least the upper electrode has a plurality of through regions through which the emitter section is exposed. The upper electrode has a surface which faces the emitter section in peripheral portions of the through regions and which is spaced from the emitter section.
    Type: Application
    Filed: September 28, 2004
    Publication date: April 7, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050062400
    Abstract: An electron emitter has an anode electrode formed on a substrate, an electric field receiving member formed on the substrate to cover the anode electrode, and a cathode electrode formed on the electric field receiving member. The cathode electrode is supplied with a drive signal from a pulse generation source, and the anode electrode is connected to an anode potential generation source (GND in this example). A collector electrode is provided above the cathode electrode, and the collector electrode is coated with a fluorescent layer. The collector electrode is connected to a collector potential generation source (Vc in this example) through a resistor.
    Type: Application
    Filed: April 2, 2003
    Publication date: March 24, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050062390
    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: Application
    Filed: August 25, 2003
    Publication date: March 24, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050057175
    Abstract: A drive circuit has a drive voltage generating circuit for generating a drive voltage, to be applied between a first electrode and a second electrode of a corresponding electron emitter, based on a selection signal from a corresponding selection line. The drive circuit further includes a modulation circuit for stepwise modulating the amplitude of a drive pulse based on a pixel signal from a corresponding signal line, for thereby controlling the luminance gradation of a corresponding pixel, wherein the drive voltage has a waveform including a drive pulse appearing in timed relation to a selection instruction from the selection line, and wherein the drive pulse, having a predetermined amplitude level, is applied between the first electrode and the second electrode, to cause at least part of an emitter to invert or change the polarization thereof to emit electrons from the electron emitter.
    Type: Application
    Filed: August 16, 2004
    Publication date: March 17, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada
  • Publication number: 20050040750
    Abstract: A light source has a light emission section comprising a two-dimensional array of electron emitters and a drive circuit for applying a drive voltage to each of the electron emitters of the light emission section. The drive circuit applies the drive voltage between upper and lower electrodes of each of the electron emitters based on a control signal representative of turn-on/turn-off from an external source (a turn-on/turn-off switch or the like), for thereby controlling each of the electron emitters. Each of the electron emitters has a plate-like emitter, an upper electrode disposed on a face side of the emitter, and a lower electrode disposed on a reverse side of the emitter.
    Type: Application
    Filed: August 16, 2004
    Publication date: February 24, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20040256995
    Abstract: One image is displayed in a period as one frame, which includes one charge accumulation period and one light emission period. In the charge accumulation period, all electron emitters are scanned, and voltages depending on the luminance levels of corresponding pixels are applied to the electron emitters which correspond to pixels to be turned on (to emit light), to accumulate charges (electrons) in amounts depending on the luminance levels of corresponding pixels in the electron emitters which correspond to pixels to be turned on. In the next light emission period, a constant voltage is applied to all the electron emitters to emit electrons in amounts depending on the luminance levels of corresponding pixels from the electron emitters which correspond to pixels to be turned on, thereby emitting light from the pixels to be turned on.
    Type: Application
    Filed: December 9, 2003
    Publication date: December 23, 2004
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20040233136
    Abstract: One image is displayed in a period as one frame, which includes one charge accumulation period and one light emission period. In the charge accumulation period, all electron emitters are scanned, and voltages depending on the luminance levels of corresponding pixels are applied to the electron emitters which correspond to pixels to be turned on (to emit light), to accumulate charges (electrons) in amounts depending on the luminance levels of corresponding pixels in the electron emitters which correspond to pixels to be turned on. In the next light emission period, a constant voltage is applied to all the electron emitters to emit electrons in amounts depending on the luminance levels of corresponding pixels from the electron emitters which correspond to pixels to be turned on, thereby emitting light from the pixels to be turned on.
    Type: Application
    Filed: March 24, 2004
    Publication date: November 25, 2004
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao
  • Publication number: 20040189548
    Abstract: A circuit element comprises a first lead wire; a second lead wire; a third lead wire; first and second rectifying elements which are connected in series in a forward direction between the first lead wire and the second lead wire; and a load which is connected between the third lead wire and a connection point between the first and second rectifying elements. V1≧V2 over an entire operating period provided that V1 represents an electric potential of the first lead wire and V2 represents an electric potential of the second lead wire. V2≦V3≦V1 in a period in which a current is blocked and does not flow into the load, provided that V3 represents an electric potential of the connection point.
    Type: Application
    Filed: March 26, 2004
    Publication date: September 30, 2004
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Iwao Ohwada, Takayoshi Akao