RECESS AND PROJECTION DETECTOR

PROBLEM TO BE SOLVED: To provide a recess and projection detector capable of detecting readily presence or absence of recesses and projections on a surface to be measured, at low costs. SOLUTION: This embodiment comprises a contactor (arm 40) of which a front end part (a probe 41) comes into contact with a surface to be measured and displaces succeeding recesses and projections of the surface to be measured; a collision sensor (pickup 50) which collides with the contactor according to the displacement of the contactor when the front end part passes through recesses and projections 21, 25, and converts vibrations due to collisions with the contactor into an electric signal; moving means which retains the contactor and the collision sensor and moves a position to a direction of an arrow A along the surface to be measured; and judging means (judging device 70) for judging presence or absence of a recess and projection part from the electric signal.