The development of an optical profilometer for determining surface profile roughness is a fairly pressing problem, as it is indicated by a considerable number of publications dealing with this subject. Analysis of the most advanced developments used in solving this problem shows two different concepts for creating such profilometer being described either by the field amplitude or phase scatter models. If a field amplitude scatter model can describe such a measuring system as BRDF, then the phase scatter model describes laser shift interferometers. The field amplitude measuring systems demonstrate a high precision in roughness determination but they need to be calibrated. For this reason it is difficult to use them to control the profile of the moving surfaces. The phase shift laser interferometers present a high accuracy but their spatial resolution limited by a size of the focused spot. As it was mentioned, they have practically reached the limit of their potentials and further progress might be made by a development and implementation of the new photodetectors with a better spatial resolution. Recent developments in the area of creating the new instruments for determination of the surface roughness presently increase an amount of software for the data processing, solving the new measuring problems, especially for the laser interferometric applications. In this paper the problems related to the creating a new amplitude-phase scatter model with the advantages of the above mentioned models are discussed with a demonstration the results of a developed appropriate software.

Date Published: 15 December 1992
PDF: 12 pages
Proc. SPIE 1776, Interferometry: Surface Characterization and Testing, (15 December 1992); doi: 10.1117/12.139241

Published in SPIE Proceedings Vol. 1776:
Interferometry: Surface Characterization and Testing
Katherine Creath; John E. Greivenkamp, Editor(s)