Patent ID: 7564495

Claim:
A thin image-capturing device for forming an image of an uneven surface of an object, said thin image forming device comprising: a primary light source; a light-guiding plate made of a transparent material and having a detection surface adapted for contacting the uneven surface of the object, a pair of lateral surfaces directly connected respectively to opposite edges of said detection surface, wherein said primary light source is disposed adjacent to one of said lateral surfaces and said lateral surface receives incident light from said primary light source, such that the incident light is able to illuminate the uneven surface of the object on said detection surface, a total internal reflection surface opposite to said detection surface, wherein said total internal reflection surface is able to reflect light that was scattered by the uneven surface of the object on said detection surface back into said light-guiding plate, a light-exiting surface, and a reflector surface connected to and forming a tilt angle with said total internal reflection surface, wherein said reflector surface is able to reflect the light that was reflected back into said light-guiding plate by said total internal reflection surface so as to cause the light to exit said light-guiding plate at said light-exiting surface; and an imaging system disposed to receive the light that was reflected by said reflector surface and that exits said light-guiding plate so as to form the image of the uneven surface of the object, said imaging system having one of a cylindrical surface and a toric surface.