| 摘要 |
PROBLEM TO BE SOLVED: To measure accurately the surface whose curvature center is approximately positioned on an rotation center, regardless of the size of the radius of curvature of the surface. SOLUTION: The surface of a measuring object 100 is irradiated with laser light so that a focal point is positioned on the rotation center (an approximate curvature center of the measuring object surface) of the measuring object 100. Hereby, even in the case where the radius of curvature is small (a), or where the radius of curvature is large (b), the largest incident angle to the measuring object surface of the laser light becomes equal as shown in the figure c, and consequently the largest reflection angle becomes equal and an expansion angle of reflected light 43 becomes equal. Resultantly, the quantity of the reflected light 43 receivable by a lens optical system 71 can be equal and excellent regardless of the size of the radius of curvature of the measuring object 100 surface. COPYRIGHT: (C)2007,JPO&INPIT
|
