Photo-induced anisotropy in electro-optical crystals

The results of theoretical and experimental studies carried out by the author on non-linear parameter transformation of light signals by a photorefractive effect in crystals are presented. The following items are considered: results of photoinduced variations of the natural eigenwaves refraction index and their polarization; formation processes of photo-charges stipulating the recording of polarizing--phase gratings due to longitudinal and transverse electrooptical effects; the operative transformation means of spatial-temporal characteristics of coherent beams; investigation results of non-stationary response providing the transformation of light beams carrying complex information in the time evolution process. Thus the main attention is focused on establishing a non-linear relationship between spatial properties of the photo-active light intensity in the image being recorded and optical anisotropy arising under the photo-charge effect.