A noncontact method for measuring the surface profile of a reflecting surface is presented. The scheme is based on the measurement of the phase difference between a surface reflected laser beam and a reference beam. Both beams are scanned past a photodetector by means of a rotating beam splitter. The slope of the surface at various points is electronically obtained, and then the surface profile in a plane is determined by direct integration. The accuracy of the method falls between the more elaborate interferometric techniques and mechanical contact schemes. A complete theoretical analysis of the method is presented as well as the results of various experimental tests.
© 1978 Optical Society of America
F. M. Smolka and T. P. Caudell, "Surface profile measurement and angular deflection monitoring using a scanning laser beam: a noncontact method," Appl. Opt. 17, 3284-3289 (1978)