The present invention relates to a light beam deflector comprising a semi-conductor light beam deflecting device (4) adapted to receive an incident beam of light (5). According to the invention the semi-conductor device comprises a planar waveguide type thin film grating deflector (4) formed in a superlattice structure and including electrodes, such that if a variable voltage is applied to the electrodes the angle through which an incident beam of light can be deflected is varied. The invention also relates to a light beam deflecting device comprising a light beam deflector (4) as above and a laser source (1, 1).