| 摘要 |
<p>PURPOSE: To detect and evaluate a rim part of an object or a plurality of rim parts of an object in a non contact method. CONSTITUTION: A work face A is scanned by focused light beam, typically laser beam emitted from a light source L at 40-45 degrees. A first and a second detector D1, D2 receive reflected light from the work face A. The first detector D1 is installed behind a focusing imaging optical system O, e.g. off axis parabolic mirrors arranged coaxially, in other words all are arranged in the surrounding of laser beam, or under light beam emitted in relation to the main work face H. The second detector D is placed approximately on light spot formed by light emitted to the main work face. The stray light measured by the first detector D1 is received at a prescribed angle to the main work face and the angle is equal to the angle between the emitted light and the plane face or smaller than that.</p> |
