A new type of holographic optical element combines some of the flexibility of computer-generated holograms with the high light efficiency of volume phase holograms to produce optical elements capable of arbitrary illumination transformations with nearly 100% light efficiency. The optical element is recorded by subdividing a volume hologram film surface into numerous small areas (facets), each of which is individually exposed. A final optical system consisting of two dichromated gelatin holograms in series is demonstrated. The first hologram spatially redistributes the incident light, and the second hologram produces a desired phase front on the redistributed light.
© 1981 Optical Society of America
S. K. Case, P. R. Haugen, and O. J. Løkberg, "Multifacet holographic optical elements for wave front transformations," Appl. Opt. 20, 2670-2675 (1981)