Applications of Bragg and non-Bragg orders in holography and interferometry

It is well known that when two beams (object and reference) are incident on a recording material, high order diffraction may be observed during both the writing and reading of the hologram. These higher or non-Bragg orders contain the phase conjugate and the phase amplified versions of the object. In this talk, the utility of Bragg and non-Bragg orders during holographic construction and reconstruction using photorefractive materials and photothermoplastics is investigated with applications to object shape determination and deformation. Specifically, we discuss applications of non-Bragg orders in the 3d reconstruction of objects, and holographic interferometry using Bragg order to determine object attitude and deformation. The advantages of using non-Bragg orders (viz., phase conjugate and phase doubling) are also discussed.