Shaped gradient lens

Abstract

One embodiment provides a method for receiving parallel rays at a lens. A first surface of the lens can receive first substantially parallel rays incoming from a first direction. The first surface of the lens also can receive second substantially parallel rays incoming from a second direction that is substantially different than the first direction. The lens can focus the first substantially parallel rays onto a first focal point on a second surface of the lens and focus the second substantially parallel rays onto a second focal point on the second surface of the lens, the second focal point being different than the first focal point.

1 - 23 . (canceled) 
     
     
         24 . A method for receiving parallel rays at a gradient lens, comprising the steps of: receiving a first plurality of substantially parallel rays incoming from a first direction at a first surface of the lens;
 receiving a second plurality of substantially parallel rays incoming from a second direction at the first surface of the lens, the second direction being substantially different than the first direction;   focusing the first plurality of substantially parallel rays onto a first focal point on a second surface of the lens; and   focusing the second plurality of substantially parallel rays onto a second focal point on the second surface of the lens, the second focal point being different than the first focal point.   
     
     
         25 . The method of  claim 24 , wherein the first and second surfaces of the lens comprise a convex shape. 
     
     
         26 . The method of  claim 24 , wherein the lens comprises a gradient index between the first surface of the lens and the second surface of the lens. 
     
     
         27 . The method of  claim 26 , wherein the lens comprises a plurality of gradient layers disposed inside the lens between the first and second surfaces of the lens. 
     
     
         28 . The method of  claim 27 , wherein adjacent gradient layers comprise different indices of refraction. 
     
     
         29 . The method of  claim 28 , wherein gradient layers closer to the first surface of the lens comprises an index of refraction less than that of gradient layers closer to the second surface of the lens. 
     
     
         30 . The method of  claim 27 , wherein the step of focusing the first plurality of substantially parallel rays onto the first focal point comprises the step of bending at least a portion of the first plurality of substantially parallel rays toward the first focal point as the first plurality of substantially parallel rays pass from one gradient layer to an adjacent gradient layer.