Design and fabrication of volume holographic optical couplers for a range of non-normal incidence angles

Abstract

A theoretical model has previously been developed to calculate the holographic recording beam angles required in air (at any recording wavelength) to produce a Volume Holographic Optical Element (VHOE) for operation as a coupler for different input and output angles. In this paper, the experimental study is extended to further validate the VHOE coupler design and fabrication approach for additional incident beam angles, comparing -40° -45° and -50° (in air). The output angle for each VHOE is +45° within the medium and the coupler operational wavelength is 633nm. Holographic recording in Bayfol HX 200 photopolymer at 532nm is used to fabricate the VHOE couplers. The experimental Bragg curves for each VHOE coupler obtained at 633 nm demonstrate agreement of the measured angles to within ±1.5° (in air) with the expected values.