Abstract: | In this work, we have theoretically and experimentally investigated the process of image amplification in photorefractive crystals as a result of the self-diffraction phenomenon. We have found that the amplification process is of the threshold type and is observed only for an angle of convergence of the light rays greater than a threshold value. The gain coefficient is rather high. For the LiNbO3 crystal, at a wavelength of 0.63 µm the gain coefficient reached 15 dB; at a wavelength of 0.44 µm, the gain was greater than 50 dB.Tomsk State Academy for Control Systems and Radioelectronics. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 22–26, June, 1994. |