Volume Grating Recording in Acrylate-Based Photopolymers

Norland Optical Adhesive (NOA) acrylate-based photopolymers were studied as a material for fabrication of volume gratings. Photopolymers were irradiated by a He-Cd laser of 325nm line interference pattern during holographic recording. We recorded transmission and reflection holograms. The formation of grating in photo-polymers can be explained by photopolymerization during the UV light irradiance. Diffraction efficiency in dependence on the sample thickness and on the polarization state/intensity of recording beam was investigated in the transmission mode. To achieve a better angular selectivity of the diffracted beam, the thickness of the prepared samples was raised up to 2.4 mm. In this work the diffraction efficiency >80% was achieved. The best angular selectivity of a diffracted beam was several minutes. Gratings with high diffraction efficiency and good angular selectivity can successfully be used in the telecommunications and data storage devices. The advantages of such a grating are long-term mechanical stability, low dependence on the temperature changes as well as simple and cheap preparation.