Patents by Inventor Fujio Matsu

Fujio Matsu 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: 5912655
    Abstract: A display device includes a liquid crystal panel, a controller, a common driver and a segment driver. The common driver is powered by a high power supply voltage and outputs row driving waveforms having predetermined voltage levels, which are relatively high. The segment driver is powered by a low power supply voltage and outputs column driving waveforms having predetermined voltage levels, which are relatively low. By this construction, it is not necessary for both the segment and common drivers to be high withstand voltage integrated circuit devices.
    Type: Grant
    Filed: February 28, 1995
    Date of Patent: June 15, 1999
    Assignee: Seiko Instruments Inc.
    Inventors: Masafumi Hoshino, Shuhei Yamamoto, Hiroyuki Fujita, Hirotomo Oniwa, Kentaro Yagi, Fujio Matsu
  • Patent number: 5815128
    Abstract: A liquid crystal display panel gray shade driving device comprises first circuitry for applying row signals represented by a set of orthonormal functions to a group of row electrodes throughout one frame by set sequential scanning for each of selecting periods, and second circuitry for sequentially carrying out a dot product computation between the set of orthonormal functions and a set of pixel data consisting of bits, and applying a column signal having a voltage level corresponding to a result of the computation to each of a group of column electrodes in synchronization with the set sequential scanning for each of the selecting periods. The first circuitry has a vertical driver for applying the row signal, by doubling the rate thereof, to the group of row electrodes and repeating the same set sequential scanning at least for two frames of previous and subsequent frames.
    Type: Grant
    Filed: December 27, 1995
    Date of Patent: September 29, 1998
    Assignee: Seiko Instruments Inc.
    Inventors: Masafumi Hoshino, Fujio Matsu, Shuhei Yamamoto
  • Patent number: 5696524
    Abstract: A display device includes a vertical driver for applying to row electrodes a set of row signals represented by a set of orthogonal functions supplied by an orthogonal function generator at each selection period by group-sequential scanning within one frame. A dot product processor successively carries out a dot product computation between the set of orthogonal functions and a set of pixel data. A horizontal driver applies to column electrodes column signals having voltage levels determined by the results of the dot product computation at each selection period in synchronization with the group-sequential scanning. A frame memory stores the pixel data for each frame in divided bit form. The dot product processor reads out the set of stored pixel data in divided bit form and executes the dot product computation to produce a column signal component for each respective bit.
    Type: Grant
    Filed: May 9, 1995
    Date of Patent: December 9, 1997
    Assignee: Seiko Instruments Inc.
    Inventors: Masafumi Hoshino, Hiroyuki Fujita, Hirotomo Oniwa, Fujio Matsu, Shuhei Yamamoto
  • Patent number: 5619224
    Abstract: In order to prevent signal distortion using a multiple line selection driving technique when using pulse width modulation to achieve a half-tone display in a liquid crystal display panel, respective bits of column signals are arranged in a descending pulse width order and a voltage generating circuit is used to lower level differences in adjacent bits. An orthonormal function generating circuit generates a plurality of row signals to drive a group of row electrodes through a vertical driver. A dot product computation circuit computes a dot product of the orthonormal functions and pixel display data to generate a column signal in the above manner. A horizontal driver applies the column signal to a group of column electrodes. Pixel data is stored in a frame memory, each datum being represented by a series of bits corresponding to a gray scale. The dot product computation circuit divides the pixel data into the respective bits, and individually carries out the dot product computation for each bit.
    Type: Grant
    Filed: December 27, 1994
    Date of Patent: April 8, 1997
    Assignee: Seiko Instruments Inc.
    Inventors: Masafumi Hoshino, Shuhei Yamamoto, Hiroyuki Fujita, Hirotomo Oniwa, Teruo Ebihara, Fujio Matsu