Elektro-optisch steuerbare Linse

The lens (8) has an electro-optical crystal plate (9) with applied surface electrodes (11,12) enabling the application of an electrical field. The crystal plate has a region (10) in which the direction of the spontaneous polarisation is inverted relative to the normal direction, with respect to the remainder of the crystal plate. The latter region is defined by a curved line in a plane perpendicular to the normal direction, and is fully covered by the rectangular electrodes applied to the upper and lower surfaces of the crystal plate. USE/ADVANTAGE - For CD player. Allows wide variation of lens focal width.