Patents Examined by Amzre Mengistu
  • Patent number: 5231382
    Abstract: The invention provides voltage potential differences for selectively discharging cells in a plasma display device, with greater brightness and reduced power consumption. The driving pulses applied to either selected cells or non-selected cells during one scanning cycle includes a high frequency hold mode period after a low frequency address mode period. During the hold mode period, a duty factor of its pulse train is selected to be smaller than that of the address mode period. Particularly, the pulse width of the pulse train in the hold mode period is shorter than an interval of pulses thereof. In other words, the duty factor of the hold mode period is selected to be less than 1/2 to decrease the voltage causing an erroneous discharge. In another embodiment, to improve brightness, the duration of hold mode is, extended to cover one more scanning cycle.
    Type: Grant
    Filed: February 27, 1991
    Date of Patent: July 27, 1993
    Assignee: NEC Corporation
    Inventor: Akio Tanaka