Continuously controllable, wide-angle liquid crystal beam deflector based on the transversal field effect in a three-electrode cell

A controllable, refractive, electro-optical liquid crystal (LC) beam deflector is studied both theoretically and experimentally. The principle of operation of this device is based on a beam deflection from a large gradient of refractive index, generated in an LC layer by a transversal electric field, formed between two lateral electrodes, in a simple three-electrode LC cell. A continuous, controllable deflection of a Gaussian laser beam, focused into the narrow region at the electrode gap is demonstrated. Maximum deflection angles of similar to 18 to 25 deg, depending on the LC birefringence, as well as a high deflection efficiency of up to 98% are demonstrated experimentally, backed by a theoretical analysis. (c) 2005 Society of Photo-Optical Instrumentation Engineers.