A shaped voltage pulse is applied to a polymer dispersed liquid crystal (PDLC) cell to control its transmission characteristics. The voltage has an initially high level that substantially exceeds the PDLC's threshold voltage. The initial voltage duration is relatively short, and is followed by a gradual...http://www.google.com.au/patents/US5170271?utm_source=gb-gplus-sharePatent US5170271 - Shaped voltage pulse method for operating a polymer dispersed liquid crystal cell, and light valve employing the same
