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 ∼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. © 2005 Society of Photo-Optical Instrumentation Engineers.