Concave-convex pattern detector

To provide a highly reliable concave-convex pattern detector. 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 [alpha] less than 90[deg.] 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 [beta] less than 90[deg.] around the other direction from the output end face 5 in the predetermined plane. The f