This paper presents the principle of a new method of laser beamsteering using the photo-refractive effect. This method uses variable, thick diffraction gratings recorded in a photorefractive medium to deflect a laser beam. Two geometrical configurations for writing .he thick gratings, and the relative merits of each are discussed using k-space diagrams. Two methods of controlling the writing beams to vary the recorded grating are also discussed. The results of a proof of concept experiment using bismuth silicon oxide crystals are reported.
Philip D. Henshaw,
"Configurations Forphotorefractive Laser Beamsteering", Proc. SPIE 0464, Solid-State Optical Control Devices, (23 May 1984); doi: 10.1117/12.966220; https://doi.org/10.1117/12.966220