| 摘要 |
PROBLEM TO BE SOLVED: To directly inspect a boundary surface between a slider and a real hard disk by compensating for influence of double refraction created by a stress pattern of a glass disk that rotates at a high speed. SOLUTION: There are disclosed a device and a method for measuring and compensating for double refraction in a rotating abrasion glass disk 2 used for an optical floating height tester utilizing polarization. A polarized light 1, 3 is projected to an upper surface 24 of a disk 20 and is refracted to pass through the disk 20. It reaches a measuring point 90 on the opposite surface 25, reflected thereat to pass through the disk 20 and refracted to go out from the disk 20. It becomes a light beam 9 including a and p polarizations. A difference of phase between s and p polarzations is measured and detected by a phase detector 13. The variation of a phase θG with respect to the position determined by the measuring position provides double refraction parameters bp , bo on the disk 20. The phase detector 13 measures the phase θG at an inclination angleξ determined in an incident plane 101 which is determined by an incident ray 3 and an exit ray 9 drown by lines passing through the measuring point 90 perpendicular to a radius line 102 of the disk 20. |
