In order to allow application of any coating under a vacuum over a volatile gelatinous
layer, such as polymer dispersed liquid crystal (PDLC) on an optical glass substrate
with a transparent electrode, such as indium tin oxide (ITO) on its surface, a
layer of an intermediate stress absorbing polymeric material is first applied to
cover the volatile gelatinous layer to prevent evaporation and escape of volatiles,
thereafter the coating is applied under a very high vacuum using for example a
technique called Physical Vapor Deposition (PVD) or sputtering.