Abstract
We have investigated prepolymers and their photo-polymerization conditions to design a holographic polymer-dispersed liquid crystal (HPDLC) device with high reflectivity. Results show that the reflectivity of an HPDLC device increases as the concentration of urethane acrylate oligomer in the prepolymers increases, and it also increases with laser intensity. These results indicate that accelerating the phase separation during photo-polymerization can improve reflectivity in HPDLCs.
We have also found that a prepolymer containing an oligomer fixes liquid crystal alignment during photo-polymerization. A reverse mode HPDLC device was demonstrated that uses this prepolymer and a dual frequency addressable liquid crystal. The device is transparent in the absence of an electric field and reflective in the presence of an electric field at a frequency higher than the cross over frequency of the liquid crystal.
