Multiple Cell Liquid Crystal Optical Device With Coupled Electric Field Control

Abstract

A liquid crystal optical device is provided. The optical device includes a liquid crystal cell controlling optical properties of light passing therethrough and has: a liquid crystal layer, a planar electrode located to one side of said liquid crystal layer; an electric field control structure located to the opposite side of the liquid crystal layer; and a wavefront adjustment structure configured to provide optical phase front adjustment. In some embodiments the wavefront adjustment structure is a conductive floating electrode. In other embodiments the wavefront adjustment structure is a weakly conductive structure having spatially variable sheet resistance. In other embodiments the wavefront adjustment structure a weakly conductive structure having spatially variable sheet resistance having a frequency dependent characteristic.

1 .- 23 . (canceled) 
     
     
         24 . A liquid crystal optical device of the type having at least one liquid crystal layer provided between substrates bearing alignment layers, and a hole-patterned electrode arrangement with a weakly conductive material within an aperture of the arrangement configured to provide a spatially modulated electric field, characterized in that:
 the hole-patterned electrode arrangement is structured to change a phase front in the liquid crystal layer by having an electrically floating electrode structure external to the electrode arrangement over the aperture; and   the hole-patterned electrode arrangement includes at least one hole patterned electrode comprising a segmented hole-patterned electrode configured to apply asymmetric phase profiles for light beam tilting, optical image stabilization and light beam shifting.   
     
     
         25 . The device as defined in  claim 24 , wherein the device is a lens, said aperture is essentially circular, and the floating electrode comprises a conductive disc positioned centrally over the aperture. 
     
     
         26 . The device as defined in  claim 25 , wherein the electrode arrangement is provided on said substrates next to the alignment layers, said conductive disc being located on a side of one of said substrates opposite a ring electrode of said electrode arrangement. 
     
     
         27 . The device as defined in  claim 24 , wherein the device is a lens, said aperture is essentially circular, and includes a spatially non-uniform layer of said weakly conductive material, the spatially non-uniform layer comprises a ring of weakly conductive material within said aperture. 
     
     
         28 . The device as defined in  claim 27 , wherein said ring of weakly conductive material is deposited on a substantially uniform layer of said weakly conductive material. 
     
     
         29 . The device as defined in  claim 24 , wherein the electrode arrangement is provided on said substrates next to the alignment layers. 
     
     
         30 . The device as defined in  claim 24 , wherein the device comprises:
 two said liquid crystal layers each having a pair of corresponding alignment layers arranged essentially in orthogonal directions between said pairs; and   at least one weakly conductive layer of said weakly conductive material.   
     
     
         31 . The device as defined in  claim 30 , wherein alignment layers within each pair of alignment layers are arranged essentially in opposite directions to each other. 
     
     
         32 . A device as defined in  claim 24 , wherein said weakly conductive material is in contact with said hole patterned electrode arrangement and spaced apart from said liquid crystal layer. 
     
     
         33 . A liquid crystal optical device of the type having two liquid crystal layers each provided between substrates bearing alignment layers, and a hole-patterned electrode arrangement with a weakly conductive material within an aperture of the arrangement configured to provide a spatially modulated electric field to each liquid crystal layer, characterized in that:
 the hole-patterned electrode arrangement includes at least one hole patterned electrode comprising a segmented hole-patterned electrode configured to apply asymmetric phase profiles for light beam tilting, optical image stabilization and light beam shifting, the hole-patterned electrode arrangement being structured to change a phase front in each liquid crystal layer by having one or more of:   an electrically floating electrode structure external to the electrode arrangement over the aperture; and   two weakly conductive layers, each weakly conductive layer corresponding to one of said liquid crystal layers.   
     
     
         34 . The device as defined in  claim 33 , wherein the device is a lens, said aperture is essentially circular, and the floating electrode structure comprises a conductive disc positioned centrally over the aperture. 
     
     
         35 . The device as defined in  claim 34 , wherein the electrode arrangement is provided on said substrates next to the alignment layers, said conductive disc being located between said liquid crystal layers. 
     
     
         36 . The device as defined in  claim 33 , wherein the device is a lens, said aperture is essentially circular, and at least one weakly conductive layer includes a spatially non-uniform layer of said weakly conductive material. 
     
     
         37 . The device as defined in  claim 36 , wherein at least one spatially non-uniform layer comprises a ring of weakly conductive material within said aperture. 
     
     
         38 . The device as defined in  claim 37 , wherein said ring of weakly conductive material is deposited on a substantially uniform layer of said weakly conductive material. 
     
     
         39 . The device as defined in  claim 33 , wherein said weakly conductive layers are in contact with each other. 
     
     
         40 . The device as defined in  claim 33 , wherein pairs of alignment layers corresponding to said liquid crystal layers are arranged essentially in orthogonal directions to each other. 
     
     
         41 . The device as defined in  claim 40 , wherein alignment layers within each pair of alignment layers are arranged essentially in opposite directions to each other. 
     
     
         42 . A liquid crystal optical device including:
 a first liquid crystal layer acting on a first light polarization provided between substrates bearing first alignment layers, a first planar electrode, a first hole patterned electrode and at least one first weakly conductive layer located adjacent to said first hole patterned electrode; and   a second liquid crystal layer acting on a second light polarization provided between substrates bearing second alignment layers, a second planar electrode, a second hole patterned electrode and at least one second weakly conductive layer located adjacent to said second hole patterned electrode,   each hole patterned electrode and corresponding weakly conductive layer being configured to provide a spatially modulated electric field to a corresponding liquid crystal layer for changing a phase front in each liquid crystal layer, characterized in that:   each hole-patterned electrode includes a segmented hole-patterned electrode configured to apply asymmetric phase profiles for light beam tilting, optical image stabilization and light beam shifting; and   the device includes an electrically floating electrode structure external to the electrode arrangement over an aperture of the device.   
     
     
         43 . The device as defined in  claim 42 , wherein the device is a lens with an essentially circular aperture, and the floating electrode structure comprises a conductive disc positioned centrally over the aperture. 
     
     
         44 . The device as defined in  claim 43 , wherein the each segmented hole patterned electrode arrangement is provided on said substrates next to corresponding alignment layers, said conductive disc being located between said liquid crystal layers. 
     
     
         45 . The device as defined in  claim 42 , wherein the device is a lens with essentially circular aperture, and at least one weakly conductive layer includes a spatially non-uniform layer of weakly conductive material. 
     
     
         46 . The device as defined in  claim 45 , wherein said spatially non-uniform layer comprises a ring of weakly conductive material within said aperture. 
     
     
         47 . The device as defined in  claim 46 , wherein said ring of weakly conductive material is deposited on a substantially uniform layer of said weakly conductive material. 
     
     
         48 . The device as defined in  claim 42 , wherein said weakly conductive layers are in contact with each other. 
     
     
         49 . The device as defined in  claim 42 , wherein pairs of alignment layers corresponding to said liquid crystal layers are arranged essentially in orthogonal directions to each other. 
     
     
         50 . The device as defined in  claim 49 , wherein alignment layers within each pair of alignment layers are arranged essentially in opposite directions to each other.