Optimized active-matrix drives for liquid crystal displays

A combination of computer simulation and experimental methods is used to pr ovide a reliable and systematic means of optimizing the response time of ac tive-matrix liquid crystal displays. Optical transients are measured and si mulated (within a continuum elastic framework including hydrodynamic backfl ow) and are thereby related to director reorientation processes under vario us driving conditions. We find that an unconventional "overdrive" method, i n which the device is briefly biased to a voltage exceeding the target volt age, leads to dramatic improvements in device response time which approach a factor of 6 in some cases. The computational model is capable of accurate ly predicting the optimum overdrive voltage. The physical origins of these findings and the importance of hydrodynamic backflow are discussed. (C) 200 1 American Institute of Physics.