Voltage controlled microlens sheet

Abstract

This disclosure provides systems, methods and apparatus relating to implementations of an electrically controlled light conditioning sheet. In one aspect, the electrically controlled light conditioning sheet includes a planar electrode having a first conductor and a second conductor and a transmissive elastic layer. The transmissive elastic layer is configured to deform in response to a potential difference applied between the first and the second conductor and produce regions of optical refractive power. The angular spread and/or the radiation pattern of an incoming beam of light incident on the electrically controlled light conditioning sheet is altered by the action of the regions of optical refractive power produced by the applied potential difference.

What is claimed is: 
     
         1 . A method of changing angular divergence of a light beam input on a light conditioning film, the method comprising:
 applying a potential difference between a first conductor and a second conductor of an electrode included in the light conditioning film;   allowing an elastic layer included in the light conditioning film to deform in response to the electric field to produce regions of optical refractive power; and   passing the input beam of light through the regions of optical refractive power such that light transmitted from the light conditioning film has an angular divergence that is different from an angular divergence ±δθ in  of the input beam of light.   
     
     
         2 . The method of  claim 1 , wherein applying the potential difference includes applying an electrical current or an electrical voltage that has a shape selected from a group consisting of DC, sinusoidal shape, square shape and triangle shape. 
     
     
         3 . The method of  claim 1 , wherein the electrode includes a plurality of interdigitated lines and applying the electric field includes generating a potential difference between adjacent interdigitated lines. 
     
     
         4 . The method of  claim 1 , wherein the regions of optical refractive power have a pitch that is at least 5 times the largest wavelength of interest of the input light beam. 
     
     
         5 . The method of  claim 1 , wherein deformation of the elastic layer produces multiple peaks and valleys, wherein a peak-to-valley deformation of the elastic layer is less than about 10% of a thickness of the elastic layer. 
     
     
         6 . The method of  claim 1 , wherein the input beam of light is emitted from a collimated light source, and wherein the angular divergence, ±δθ in  of the input beam of light emitted from the collimated source is less than 15 degrees from normal to the light conditioning film. 
     
     
         7 . The method of  claim 1 , wherein deformation of the elastic layer produces multiple peaks and valleys to form a plurality of substantially spherical regions. 
     
     
         8 . The method of  claim 1 , wherein the first conductor includes a plurality of conductive extensions, and wherein the second conductor includes a plurality of conductive extensions, wherein each of the plurality of conductive extensions of the second conductor includes an arcuate region that partially surrounds a conductive extension of the second conductor. 
     
     
         9 . A method of manufacturing a light conditioning film, the method comprising:
 providing a transmissive substrate having a transmissive elastic layer over the substrate; and   disposing an electrode pattern over the substrate or over the transmissive elastic layer,   wherein the elastic layer is configured to deform and produce regions of optical refractive power in response to a potential difference applied across adjacent conductors in the electrode pattern, and   wherein the regions of optical refractive power change an angular divergence of light incident on the light conditioning film and passing through the elastic layer.   
     
     
         10 . The method of  claim 9 , wherein providing the transmissive substrate having a transmissive elastic layer includes disposing the elastic layer over the substrate by way of at least one of: compression molding, casting, spin-coating, and dip coating. 
     
     
         11 . The method of  claim 9 , wherein disposing the electrode includes at least one of: thin film processing, patterning, and lithography. 
     
     
         12 . The method of  claim 9 , wherein disposing the electrode pattern comprises adhering the electrode pattern to the substrate. 
     
     
         13 . The method of  claim 9 , wherein disposing the electrode pattern comprises at least partially embedding the electrode pattern in the substrate. 
     
     
         14 . The method of  claim 9 , wherein disposing the electrode pattern comprises at least partially embedding the electrode pattern in the elastic layer. 
     
     
         15 . The method of  claim 9 , further comprising disposing a second electrode on a surface above the electrode pattern. 
     
     
         16 . The method of  claim 9 , wherein deformation of the elastic layer produces multiple peaks and valleys, wherein a peak-to-valley deformation of the elastic layer is less than about 10% of a thickness of the elastic layer. 
     
     
         17 . The method of  claim 9 , wherein the incident light is emitted from a collimated light source, and wherein the angular divergence, ±δθ in  of the incident light emitted from the collimated source is less than 15 degrees from normal to the light conditioning film. 
     
     
         18 . The method of  claim 9 , wherein deformation of the elastic layer produces multiple peaks and valleys to form a plurality of substantially spherical regions. 
     
     
         19 . The method of  claim 9 , wherein the electrode pattern includes a first conductor having a plurality of conductive extensions, and a second conductor having a plurality of conductive extensions, wherein each of the plurality of conductive extensions of the second conductor includes an arcuate region that partially surrounds a conductive extension of the second conductor. 
     
     
         20 . A method of manufacturing a lighting device, the method comprising:
 providing a light source including the light conditioning film manufactured by the method of  claim 9 ; and   providing a fixture adapted to receive the light source.