Hologram phase separation

When the hologram is illuminated with a beam similar to the original reference wave, it modulates the phase and/or amplitude ol llie illuminating wave in such a way that the transmitted wave divided into three separate components, one of which exactly duplicates the original object wave. 

Azobenzene-Containing Materials for Hologram describes block copol)rmers with well-defined structures that can eliminate the scattering of visible light by microphase separation and prohibit photoinduced surface deformation when azobenzene blocks form the minority phase. Thick films (> 200 microns) with good optical transparency can be prepared with random copol)rmers or blended block copolymers, for recording volume holograms. 

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