Effects of Material Systems on the Polarization Behavior of Holographic Polymer Dispersed Liquid Crystal Gratings

This study has investigated the effects of the material systems involved in the fabrication processes on the polarization behavior of a volume holographic grating. The diffraction efficiency of the gratings fabricated using prepolymer/liquid crystal mixtures shows strong dependence on the polarization of incoming light. Depending on the materials used in the formation of a grating, the diffraction properties are such that either p- or s-polarized light is strongly diffracted while the light with the other polarization is very weakly diffracted. The magnitude of the dependence on the polarization is greatly affected by the type of monomers, liquid crystals and substrates. The comparison of various types of monomers added to the base prepolymer mixtures, two distinctly different types of liquid crystals and glass slides and indium-tin oxide (ITO) coated glass as substrates was carried out using polyester-based and urethane-based oligomers.