Patent ID: 8228472

Claim:
An electrically tunable liquid crystal lens comprising: a planar liquid crystal layer supported between an opposed pair of transparent, insulating, alignment layers; a first planar electrode formed of a transparent conductive material supported adjacent to one of the alignment layers on the opposite side of the liquid crystal layer; a second transparent conductive electrode disposed on the second alignment layer on the side opposite to the liquid crystal layer, the second electrode comprising only one central tip electrode; and a variable voltage power supply connected to the first and second electrodes so as to impose a nonhomogeneous electric field on the liquid crystal layer, the field having a maximum intensity at a center of the electrodes and decreasing toward the edges of the electrodes, so that the refractive index of the liquid crystal layer is adjusted in a nonhomogeneous manner to provide a lens effect to light passing through the cell, the focal length of the lens being a function of the applied voltage between the electrodes.