<title>Electrical properties of polymer-dispersed liquid crystal films</title>

Abstract

Polymer-dispersed liquid crystal (PDLC) films are useful in light control applications because they can be switched electrically between light scattering and transparent states. PDLC films are also being considered for solar heat load reduction because they can be made to backscatter the solar radiation. Since the size of the PDLC film required for such applications could be as large as one or more square meters, special consideration must be given to the electrical power required to activate those (mostly capacitive) films. We measured the electrical response of PDLC films to applied voltages of amplitude and frequency in the range of those typically used in most applications. A voltage-dependent and materials-based RC circuit was developed to model the PDLC film and its circuit parameters were adjusted to fit the data. We found that the model and the fitted values of the circuit parameters are useful for understanding the electrical properties of PDLC films and identifying sources of power consumption. In addition, the values obtained for the circuit parameters allowed us to estimate several previously unknown PDLC material parameters.