Abstract

We have developed a new and useful technique for the quantitative optical analysis of microscopic phase objects and specular surfaces. This technique, based on recent developments in moire deflectometry, provides quantitative ray deflection maps of microscopic objects as well as contrast enhancement. The apparatus and its use are extremely simple and are readily adapted to most optical microscopes by the insertion of a recollimating lens and a matched grating pair external to the eyepiece. The dynamic range (i.e., the sensitivity to ray deflection) of the instrument is (continuously) varied merely by adjusting the spacing between the gratings. The ray deflection map of a microscopic sample can be interpreted straightforwardly to provide a slope map of specular objects or a refractive-index gradient map (or optical thickness gradient map) of phase objects. We compare this technique to interferometric, schlieren, and phase contrast methods now in common use and present some illustrative applications.

© 1985 Optical Society of America