Retroreflective grating generation and analysis for surface measurement.

An efficient system for retroreflective grating generation andanalysis has been constructed to measure the derivative and the contourof specular surfaces. In this system, a new optical configurationhas been provided to generate and capture a grating image with aretroreflective screen. Tests show that the system can detectindents and outdents with a maximum depth of less than 10mum. The method can be developed for automated industrialinspection and machine vision.