Method and apparatus for driving active matrix liquid crystal device
AssigneeCanon Kabushiki Kaisha
InventorsShuzo Kaneko, Akio Yoshida, Ryoji Fujiwara
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Abstract
An active matrix liquid crystal device is driven by sequentially applying a first scanning pulse to reset each pixel on a first selected line, a second scanning pulse to write each pixel on a second selected line and a third scanning pulse to provide a voltage signal which is equal to or less than the optical threshold value of the liquid crystal to each pixel on a third selected line. According to the driving method, the first, second and third selected lines are spaced at a predetermined number of lines from each other, and a sum of time integrated values of the applied voltage signals is or approaches zero.
Claims13
A method of driving an active matrix liquid crystal device, in which the device incorporates a liquid crystal having a memory performance and is line scan sequentially driven with an access time for accessing the pixels of each line of the device, said method comprising the steps of:
- applying a first scanning pulse in a reset interval in a first vertical scanning operation to provide a reset voltage signal for resetting each pixel on a first selected line;
- applying a second scanning pulse in a recording interval in a second vertical scanning operation to provide a recording voltage signal for writing each pixel on a second selected line;
- and
- applying a third scanning pulse in a further interval in a third vertical scanning operation to provide a further voltage signal, whose level is equal to or less than an optical threshold value of the liquid crystal, to each pixel on a third selected line,
- wherein the first, second and third selected lines in each of said reset interval, said recording interval and said further interval are spaced at a predetermined number of lines from each other, and wherein a sum of time integrated values of the voltage signals which are applied to the pixels is equal to almost zero.
Dependencies are inferred from the claim text.