kHz-speed optically induced phase gratings with liquid crystal light valves in transient dynamic mode.

Liquid crystal light valves (LCLV) are optically addressable spatial light modulators that allow controlling the phase and amplitude properties of optical beams. We show that sub-milliseconds phase and amplitude modulations can be obtained when operating the LCLV in the transient dynamic mode by setting the working point close to the saturation of the response. Thanks to the large birefringence of the liquid crystals, this condition provides enough phase shifts to respond to the needs of several methods for optical measurement, dynamic holography, interferometry, and imaging through phase disturbing media, while providing kilohertz (kHz) speed. These values of response times also allow foreseeing applications, for example, in biophotonics, and for monitoring the environment.