Patent ID: 7824091

Claim:
A backlight arrangement comprising at least a first and a second light source providing light having a first and a second angular spread to a first and a second waveguide plate respectively, each of the first and the second waveguide plate comprising a front surface and an opposing back surface and at least one surface for receiving light from said corresponding first and second light source, said at least one surface connecting said front and back surfaces, wherein at least one of said front surface and back surface is a facetted surface comprising a plurality of planar parallel portions and a plurality of facets connecting said planar parallel portions, the plurality of facets being formed such that the thickness of said waveguide plate decreases stepwise with the distance from said surface for receiving light, and such that at least part of the light received into each of the first and the second waveguide plate via said surface for receiving light is extracted from each of the first and the second waveguide plate through said plurality of facets.