OPTICAL-ABERRATION CORRECTION BY REAL-TIME HOLOGRAPHY IN LIQUID-CRYSTALS

We present results of experiments that use nematic-phase liquid crystal as a real-time holographic recording medium. Plane-wave gratings were written with as little as 10 mJ/cm2 of incident write-beam energy from a pulsed Nd:YAG laser, and diffraction efficiencies greater than 25% were measured at 633 nm. Grating decay times were observed to fall within two distinct time regimes: a rapid-decay time of 60 to 100 μsec and a slower-decay time of 6 to 30 msec. The rapid-decay regime was used to demonstrate real-time correction of severely aberrated images by degenerate four-wave mixing. © 1990 Optical Society of America.