Abstract

Surface relief (SR) gratings with a molecularly oriented structure and pure polarization hologram were fabricated on a photo-cross-linkable liquid crystalline copolymer using a 325 nm laser with various two beam polarization modes. For intensity holography, the polarization information from the two beams simultaneously provided the molecular motion and molecular reorientation; the SR height reached up to 186 nm and the concave area revealed a molecular reorientation when the exposing beams were linearly polarized. In contrast, SR formation was negligible for polarization holography when molecular reorientation due to the polarization modulation was observed. The resulting polarization gratings changed the polarization property of the diffraction beams, and their diffraction efficiency was up to 24%, which agreed with theoretical expectations.