High-efficiency Phase-hologram Gratings

Optimum conditions for the generation of high-efficiency hologram gratings are presented. The most efficient phase holograms were obtained for exposures 10 to 20 times larger than those for optimally exposed amplitude holograms. Hologram gratings produced on Agfa Gevaert 8 E 70 recording plates diffracted 40 percent of the incident radiation into the holographic image. This experimentally obtained efficiency is 60 percent of the theoretical maximum for a hologram with a geometric parameter Q of 4.6.