Generalilzed Beamforming with Multiple Computer Originated Holograms
Final rept. Oct 1985-Oct 1988
ENVIRONMENTAL RESEARCH INST OF MICHIGAN ANN ARBOR ADVANCED CONCEPTS DIV
Pagination or Media Count:
Generalized beamforming with optical systems using multiple computer- originated holographic optical elements HOEs was studied theoretically, through computer simulations, and through fabrication and experiments. A two HOE system was built for polar formatting of spotlight synthetic aperture radar data and was used with a spatial light modulator and a third phase-correcting HOE for real-time image formation. A two HOE system was designed using a novel iterative algorithm and successfully used for energy-efficient conversion of a Gaussian beam to a uniform far-field beam. A necessary condition was derived that a one- to-one coordinate transformation must satisfy to enable it to be performed with only two optical coordinate tranformations, each using the stationary phase approximation. Because of the importance of computer-generated holograms to this work, a brief study was made of computer-generated hologram fabrication facilities. Keywords Computer generated holograms Holographic optical elements.