Patents by Inventor Seiji Okamoto

Seiji Okamoto 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: 5432513
    Abstract: In a codec having a coding section A/D converting an analog signal into a digital signal, and a decoding section D/A converting a received digital signal into an analog signal, a decoding timing generating circuit (50) is provided to generate a D/A conversion timing signal (S50) on the basis of a clock signal (S30b) generated by a coding PLL circuit (30) and a reading completion signal (S61a) supplied from decoding controller (61). In synchronism with this signal (S50), a D/A converter 62 converts the digital signal Di read by the decoding controller 61, into an analog signal, and sends it to the decoding filter 63. The decoding filter (63) operates synchronism with the clock signal (S30b) generated by the coding PLL circuit (30) to filter the output of the D/A converter (62), and outputs it as the analog signal (Ao).
    Type: Grant
    Filed: September 8, 1994
    Date of Patent: July 11, 1995
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Seiji Okamoto
  • Patent number: 5420934
    Abstract: An electronic sound processing system comprises a sound waveform looping apparatus which cuts out a portion of an input sound waveform and conducts a looping process for a predetermined cycle of the portion of the waveform. The sound waveform looping process comprises a discrete Fourier transformer for applying a discrete Fourier transform to the input sound waveform, a frequency band remover for removing a predetermined frequency band of the discrete Fourier transformed sound waveform, an inverse discrete Fourier transformer for applying an inverse discrete Fourier transform to the sound waveform from which the predetermined frequency band has been removed, and a looping processor for looping a predetermined cycle of the inverse discrete Fourier transformed sound waveform. By executing the sound waveform looping process, the electronic sound processing system can obtain smooth looped waveforms with easy processes and simple equipment.
    Type: Grant
    Filed: April 14, 1994
    Date of Patent: May 30, 1995
    Assignee: Kabushiki Kaisha Kawai Gakki Seisakusho
    Inventor: Seiji Okamoto
  • Patent number: 5379294
    Abstract: An analog front-end circuit has a low-group low-pass filter and a low-group high-pass filter connected in series, a high-group low-pass filter and a high-group high-pass filter connected in series, and switching means enabling the low-group high-pass filter and high-group low-pass filter to be connected in series, thus providing three bandpass filters with different passbands.
    Type: Grant
    Filed: March 28, 1991
    Date of Patent: January 3, 1995
    Assignee: Oki Electric Industry Co., Ltd.
    Inventors: Hisao Ohtake, Seiji Okamoto, Shoji Fujii
  • Patent number: 5289058
    Abstract: An operational amplifier circuit is composed of a differential amplifier circuit for delivering a signal which is obtained by amplifying a difference between voltage levels of two signals; a level shift circuit for shifting and delivering the voltage level of the signal delivered from the differential amplifier circuit; a first amplifier circuit for amplifying and delivering the signal from the level shift circuit; and a second amplifier circuit for amplifying and delivering the voltage level of the signal delivered from the differential amplifier circuit, and a CMOS output circuit whose conductive state is controlled in accordance with voltage levels of the signals delivered from the first and second amplifier circuits.
    Type: Grant
    Filed: November 24, 1992
    Date of Patent: February 22, 1994
    Assignee: Oki Electric Industry Co., Ltd.
    Inventor: Seiji Okamoto
  • Patent number: 4494824
    Abstract: A liquid crystal display device comprises a pair of opposed substrates, a transparent electrode on at least one of the substrates, a liquid crystal composition, a characteristic orienting film comprising an organic high copolymer resin film formed at least over the surface of the electrode, and which shows an excellent orientation, and conductive particles mixed within the orienting film to reduce the resistance of the orienting film.
    Type: Grant
    Filed: December 17, 1982
    Date of Patent: January 22, 1985
    Assignee: Sharp Kabushiki Kaisha
    Inventors: Takeshi Nakamura, Seiji Okamoto, Kazuyoshi Hirayama