Multiple exposure holography in volume materials

The objectives can be grouped into three categories: (1) extension of the coupled wave theory to include diffraction in multiply-exposed, thick holographic gratings; (2) study of the exposure properties of dichromated gelatin films including multiple exposures and nonlinearities; and (3) combining the diffraction analysis and the film properties study to produce a number of new diffractive optical elements. The coupled wave diffraction theory was extended to include double exposure holographic gratings for the geometry where two gratings have a common central Bragg angle. Closed form analytic solutions for diffraction efficiency are obtained for several readout geometries. The phenomenon of 100% efficient cross-coupling is predicted and experimentally verified. The coupled wave theory for the geometry where two angularly offset gratings are superimposed in one emulsion is then developed.