Laser ranging system having reduced sensitivity to surface defects

摘要

An improved apparatus and method for measuring the distance between a known point and a point of the surface of a component having an imperfection therein. The apparatus includes an optical range finding system having a light source that generates a collimated beam of light for illuminating the point on the surface of the component and a detector for receiving light reflected from the point on the surface. The detector generates a signal indicative of the distance between the known point and the point of illumination. The present invention utilizes an actuator for moving the component in a plane perpendicular to a line from the known point to the point on the surface such that the collimated beam scans an area larger than the imperfection. The output of the detector is averaged over the scanned area to provide a distance measurement that is less sensitive to the imperfection.