Patents Examined by David M. Miller
  • Patent number: 4920410
    Abstract: A drive method for a color CRT in which a point-sequential color video signal is produced to drive a modulation electrode of the CRT, in which an index signal is generated consisting of pulses at a frequency identical to a frequency of scanning successive screen phosphor color trios of the CRT, multi-phase index signals are derived from that index signal, and respective time differences between scanning timings of each color trio in each scan line and a specific index signal phase are successively measured, stored in memory, and subsequently read out to produce timing control signals for gating the color components of the point-sequential video signal. Requirements for timing accuracy and assembly precision of the CRT can thereby be substantially relaxed by comparison with a prior art single-phase index signal method.
    Type: Grant
    Filed: April 25, 1988
    Date of Patent: April 24, 1990
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kaoru Tomii, Hiroshi Miyama, Yoshikazu Kawauchi, Jun Nishida