Experimental results on optical effects induced in epoxy resin based PDLC

A thermosetting matrix based on a bifunctional epoxy resin was employed to realize a Polymer Dispersed Liquid Crystal (PDLC) system. Two different switching effects From an opaque to a transparent state have been observed: an electro-optical one occurring at a threshold value of the applied electric field and a self-switchi effect of thermal nature, occurring at a critical incident intensity in a PDLC. The experimental results showed promisi switching times with a rise time of 200 mu sec and a decay time of 2.2 msec and an exceptionally high contrast ratio up to 430 for the electro-optical switch. The self-transparency effect is taking into account the beam profile variations of the light propagating inside such a medium. A three-dimensional analysis is reported.