METHOD AND APPARATUS FOR EVALUATING SURFACE DISPLACEMENT

摘要

PROBLEM TO BE SOLVED: To provide a method and apparatus for evaluating the displacement of a surface while requiring no optical lens in an optical path and ensuring a high accuracy although using a simple structure. SOLUTION: The invention includes: a beam scanning means 2 for scanning laser beams; a photoelectric sensor 5 for receiving the laser beam applied to the surface of a sample and reflected; one or two parabolic mirrors 3, 4 provided within the optical path of an optical system; a shield part 6 provided on the light-receiving surface of the photoelectric sensor 5; and a judging means for judging the condition of the sample surface from an output of the photoelectric sensor 5.