| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface inspection device and a defect measurement method, which have high spacial resolution with a large lift-off, capable of measuring defects under scale.SOLUTION: The surface inspection device comprises: a nonlinear optical crystal 5 for generating a terahertz wave; a parabolic mirror 7 and a polarizing plate 19 for collimating the terahertz wave generated from the nonlinear optical crystal 5 and for emitting the terahertz wave including P polarized light to a steel plate 8 at a Brewster angle for an oxide film of the steel plate 8; a terahertz wave detection device 17 for detecting a terahertz wave intensity distribution, which is reflected on an interface between the steel plate 8 and the oxide film of the steel plate 8, on a plane perpendicular to the advancing direction of the terahertz wave; and a defect determination device 18 for detecting a defect on the basis of the terahertz wave intensity distribution detected by the terahertz wave detection device 17. |
