Patents by Inventor Katsumi Ashizawa

Katsumi Ashizawa 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: 20070085776
    Abstract: An electron emission type display apparatus has on a flat plane a matrix layout of multiple light-emitting elements which are connected to cross-points of longitudinal and lateral common electrodes, for sequentially turning on a line of light-emitting elements connected to a common electrode. In such the device, distortion takes place in drive waveform since a low-pass filter (LPF) is formed by a combination of the wiring resistance of the common electrode and the capacitance of a light-emitting element. To avoid such waveform distortion, the width of a light-emitting element driving voltage pulse is caused to be greater than the width of a scan voltage pulse.
    Type: Application
    Filed: September 19, 2006
    Publication date: April 19, 2007
    Inventors: Mikio Shiraishi, Eiji Miwa, Toshiyuki Kurita, Katsumi Ashizawa
  • Publication number: 20060221001
    Abstract: A display unit converts the image signal having the converted frame rate into an interlacing scanning format when the scanning frequency of a progressive image signal having the converted frame rate is higher than a predetermined value. The predetermined value corresponds to the maximum operation frequency of a display device or a drive circuit that drives the display device.
    Type: Application
    Filed: February 2, 2006
    Publication date: October 5, 2006
    Inventors: Takaaki Matono, Mutsumi Suzuki, Toshimitsu Watanabe, Fumio Haruna, Katsumi Ashizawa
  • Publication number: 20060092115
    Abstract: The invention intends to realize long lifetime of electron-emitter elements and a display apparatus by preferably eliminating charges accumulated in the electron-emitter elements. The display apparatus of the invention has: a non-display period extending circuit for extending a non-display period of an input video signal to a period longer than the non-display period of the input video image and outputting the extended signal; a plurality of electron-emitter elements for emitting electrons on the basis of the video signal outputted from the non-display period extending circuit; and a scan driver having a pulse applying circuit for applying a pulse signal to the electron-emitter elements in the non-display period of the video signal extended by the non-display period extending circuit. A pulse width of the pulse signal is set to be longer in accordance with the extended non-display period.
    Type: Application
    Filed: August 26, 2005
    Publication date: May 4, 2006
    Applicant: Hitachi, Ltd.
    Inventors: Takaaki Matono, Mutsumi Suzuki, Toshimitsu Watanabe, Katsumi Ashizawa