Hologram build-up in a near infrared sensitive photopolymer

A self-processing photopolymer material suitable for holographic recording in the near infrared region (at 780 nm) has been studied. It has been shown that the amount of the pre polymerizing exposure plays a crucial role in the build-up of the holographic grating. By a proper choice of the pre-exposure it is possible to reduce the inhibition period and to optimize holographic sensitivity and maximum diffraction efficiency. Maximum diffraction efficiencies above 70% have been measured. Significant differences have been found between gratings recorded with s and p polarised beams. (C) 2000 Elsevier Science B.V. All rights reserved.