Applications of photorefractive materials include holographic data storage, image processing (amplifiers, novelty filters, optical correlators), imaging through turbid medium, phase conjugation, optical limiting, optical computing, non-contact surface defect control, optical waveguiding, and many others.L. Solymar, D. Webb, A. Grunnet-Jepsen, "The physics and applications of photorefractive materials", Clarendon Press: Oxford, 1996