US 7,537,369 B2
	Surface radiation conversion element, liquid crystal display device, and method of producing a surface radiation conversion element
Yoshiki Takata, Taki-gun (Japan)
Assigned to Sharp Kabushiki Kaisha, Osaka (Japan)
Filed on Feb. 27, 2004, as Appl. No. 10/787,188.
Claims priority of application No. 2003-053551 (JP), filed on Feb. 28, 2003.
Prior Publication US 2004/0228112 A1, Nov. 18, 2004
Int. Cl. F21V 7/04 (2006.01)

U.S. Cl. 362—606  [382/600; 382/615; 382/616; 382/618]

39 Claims

1. A liquid crystal display device having a surface radiation conversion element for converting an electromagnetic wave, which is radiated from a radiation source, to surface radiation, characterized in that an element body has a generally plate shape constituted with a material having a larger electric permittivity than air outside said element body and, in the inside of the element body, a plurality of recesses formed in one surface of said element body form completely closed spaces of substantially uniform size on said one surface and whose electric permittivity is smaller than that of the material constituting the element body and whose surfaces opposite to a radiation surface are generally flat, wherein a number of said completely closed spaces near an edge of the element body near the radiation source is of greater density than the density of said completely closed spaces in a central portion of the element body.