| 摘要 |
A liquid crystal display unit has a video signal receiver and a first store for storing video signals. Time-modulation grey-scale addressing of the ferroelectric liquid crystal pixels in a display panel is provided to a change-of-state store which records the number of changes of state for each pixel during one picture-signal. Once the most-significent bit has been processed and is being displayed on the panel, the change-of-state store has the net number of changes which the pixel has undergone in that picture. A controller causes the change-of-state store to output the value appropriate to that pixel and pass it to a pixel driver unit to produce a compensating pulse (whether positive, negative or zero) necessary to ensure that there is no net electrical potential over the entire picture interval. The display produced by the compensating pulse is cleared immediately the first data of the next picture is input to the pixel. Assuming that the LSB of the data for a pixel is already on display in the display panel, then in the next scan, a bit extractor passes the next LSB to a comparator whose other input is connected to a pixel-state store. Accordingly, the new bit-value is compared with the existing state of the pixel, and the comparator passes on an instructing signal to the pixel driver unit only if the state of the pixel requires changing; in such an eventuality, the pixel driver unit issues an appropriate monopulse select voltage. The comparator also passes such an instructing signal. |
