Patents Examined by Kevin N. Nguyen
  • Patent number: 6414668
    Abstract: Arrangement of connection points of sampling switches to video bus lines within a signal line drive circuit 200 is improved such that connection points of video buses (SVn1 to SVn6) supplied with positive-polarity video signals relative to a predetermined reference potential and video buses (SVp1 to SVp6) supplied with negative-polarity video signals to analog switches (SWn11 to SWn22 and SWp11 to SWp22) make substantially symmetric patterns in the extending direction of the video buses. Since the sum of lengths of connection wirings belonging to a switch pair and their total resistance value becomes substantially equal in all switch pairs, the effective vales of shift amounts in signal line potentials are substantially flattened. Therefore, here is provided a drive circuit built-in liquid crystal display device realizing a good imaging quality removing noise such as stripe-shaped imaging defects which may occur when video signals are supplied to analog switches through a plurality of video buses.
    Type: Grant
    Filed: January 21, 1999
    Date of Patent: July 2, 2002
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Masao Karube, Kazuo Nakamura, Masaki Miyatake, Hoko Hirai, Akihiko Saitoh, Yoshiro Aoki