Directional optical coupler

Abstract

A directional optical coupler is shown and described, which includes an optical cell that is made of a first transparent conductor, a second transparent conductor and an electro-optical member interposed between the two transparent conductors, the electro-optical member having an index of refraction which can be varied only along one crystal axis by application of an electric field.

1 . An optical coupler comprising: 
 at least two optical cells each capable of changing the direction of light, each optical cell including: 
 a first optically transparent electrode;  
 a second optically transparent electrode and spaced from said first optically transparent electrode; and  
 an electro-optic layer interposed between said first optically transparent electrode and said second optically transparent electrode, said electro-optic layer having an index of refraction that is substantially variable only along one crystal axis upon application of an electric field and negligible along other crystal axes for said electric field;  
   wherein one optical cell is disposed over the other optical cell, and where one optical cell is larger than the other optical cell.    
   
   
       2 . An optical coupler according to  claim 1 , wherein electric field is created by application of a voltage between said first optically transparent electrode and said second optically transparent electrode.  
   
   
       3 . An optical coupler according to  claim 1 , wherein said electro-optic material comprises of Strantium Barium Niobate.  
   
   
       4 . An optical coupler according to  claim 1 , further comprising a substrate, wherein said optical cells are disposed over said substrate.  
   
   
       5 . An optical coupler according to  claim 1 , wherein said first optically transparent electrode and said second optically transparent electrode comprise of Indium-Tin oxide.