US 7,616,881 B2
Zoom flash with liquid crystal lens
Rongguang Liang, Penfield, N.Y. (US); Xiang-Dong Mi, Rochester, N.Y. (US); and David Kessler, Rochester, N.Y. (US)
Assigned to Eastman Kodak Company, Rochester, N.Y. (US)
Filed on Apr. 03, 2007, as Appl. No. 11/695,734.
Prior Publication US 2008/0247743 A1, Oct. 09, 2008
Int. Cl. G03B 15/06 (2006.01); G03B 15/02 (2006.01); G02B 3/12 (2006.01); F21V 9/14 (2006.01)
U.S. Cl. 396—175  [359/666; 362/17; 362/18; 362/19; 362/355] 13 Claims
OG exemplary drawing
 
1. A zoom flash comprising:
a first solid optical element;
a liquid crystal element;
a first electrode between the first optical element and the liquid crystal element;
a second solid optical element;
a second electrode between the liquid crystal element and the second optical element;
an electronic controller for applying a voltage across the first and second electrodes;
wherein an optical power of the liquid crystal element changes according to the voltage applied;
a light source on a side of the first optical element opposite the first electrode; and
wherein light passing through the first, liquid crystal, and second optical elements is redirected by the elements and wherein a diffuser is located adjacent the second optical element on a side of the second optical element opposite the second optical electrode.