Patent ID: 9500955
Filing Date: 2016-11-22
CPC Classification: G03F

Claim Text:
1. An exposure apparatus comprising a light source and a diffusing sheet provided below the light source, wherein a side of the diffusing sheet adjacent to the light source is an incident side and the other side opposite to the incident side is an emitting side; light emitted from the light source enters the diffusing sheet through the incident side, is refracted within the diffusing sheet, and after being diffused, emits out evenly throughout the emitting side, one of the incident side and the emitting side is a flat surface, and the other comprises a central spherical surface and a plurality of concentric annular cambered surfaces and a distance between each concentric annular cambered surfaces and an immediately inner concentric annular cambered surface becomes larger from a center thereof; wherein the diffusing sheet is located between the light source and the mask plate carrier.