Abstract

Since the discovery of optical phase conjugation in 1972 researchers tried to generate phase conjugated beams with different nonlinear media and various techniques for many applications^1-3. Self-pumped phase conjugation (SPPC) is obtained by stimulated Brillouin scattering or wave mixing in photorefractive crystals. The SBS-effect is observed with pulsed lasers at a high threshold power in the range of about 10 kW whereas photoreffactives operate with continuous powers in the mW-range. These crystals are expensive and available only for small optical apertures of about 1 cm². In contrast liquid crystal cells may have much larger dimensions and offer also high optical nonlinearities. It was shown⁴ that self-pumped phase conjugation in liquid crystals can be realized by wave mixing effects with threshold powers less than 1 W.

© 1996 Optical Society of America