| 摘要 |
PROBLEM TO BE SOLVED: To obtain an apparatus for inspecting the surface of a disk, which has reduced background noise and is capable of especially detecting projected fine flaws with high sensitivity. SOLUTION: The apparatus for inspecting the surface of the disk consists of a light surface unit for emitting a laser beam L having a wavelengthλ, a proximity optical element 10 having a refractive index (n) arranged at a distance of the wavelengthλor shorter from the surface of a disk substrate 1 and a photodetector 16 for detecting the scattered light of the evanescent light from the element 10. The optical axis of laser beam L is set to sin-1 (1/n) or smaller, with respect to a normal line N, and the incident optical axis C2 of the photodetector 16 is set to sin-1 (1/n) or larger with respect to the normal line N.
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