Patent ID: 8049845

Claim:
An optical diffusion device comprising: a plate having one side and an opposite side; multiple optical microstructures provided on at least one of the side and the opposite side of the plate; and multiple light sources disposed on the one side of the plate, with each light source having a long direction and a short direction, wherein each optical microstructure has a longer axis and a shorter axis; with the longer axis of each optical microstructure being approximately arranged in parallel with the long direction of the multiple light sources, with the one side of the plate being intermediate the multiple light sources and the opposite side of the plate, wherein the one side of the plate is an incident plane and the opposite side is an irradiation plane opposite to the incident plane; wherein the multiple light sources are disposed below the incident plane; wherein each optical microstructure is disposed on the irradiation plane; and wherein the multiple optical microstructures are more densely arranged over the multiple light sources.