CONCAVE-CONVEX PATTERN DETECTOR

PROBLEM TO BE SOLVED: To provide a highly reliable concave-convex pattern detector. SOLUTION: The concave-convex pattern detector comprises a slant FOP 3 having an input end face 4 that an object surface comes in contact with and an output end face 5 roughly parallel to the input end face 4, an irradiation light source 10 disposed on the output end face 5 side of the slant FOP 3 for irradiating the output end face 5 with light, and a CCD camera 11 disposed on the output end face 5 side of the slant FOP 3 for detecting a concave-convex pattern based on the light emitted from the output end face 5. The optical axis Rf of an optical fiber 6 is slanted to form a first angle α less than 90° around one direction from the output end face 5 in a predetermined plane roughly perpendicular to the output end face 5. The irradiation light source 10 irradiates the output end face 5 with light from a direction forming a second angle β less than 90° around the other direction from the output end face 5 in the predetermined plane. The first angle α and the second angle β are set such that the light incident on a core 8 of the optical fiber 6 from the output end face 5 enters a clad 9. COPYRIGHT: (C)2011,JPO&INPIT