Methods for driving electrophoretic display so as to avoid persistent unidirectional current through TFT switches

摘要

Certain types of displays such as electrophoretic displays tend to deteriorate if their pixel units are persistently driven by currents flowing in only one direction for the purpose of maintaining (i.e. refreshing) a relatively constant optical state. A first method pulses the pixel unit with a drive pulse of opposed polarity but duration too short (i.e. less than 1/25 second) for a viewer to notice. A second method pulses the pixel unit with a drive pulse of opposed polarity but magnitude to small to effect change in optical state.