Novel concept for obtaining continuously variable topographic contour mapping using holographic interferometry

A holographic technique is developed which allows one to obtain in real time the contour map of an arbitrarily shaped object. The method provides a relatively coarse contouring of the object. While still operating at low sensitivities, the method suffers from a breakdown in its functioning due to a saturation of the phase carrying capacity of the interferometer. As a consequence, a phase management strategy is introduced, whose incorporation to the technique enables a substantial improvement of its performance. These developments are systematically analyzed and presented. The method is whole field and noncontacting. The live and flexible character of the method enables one to rapidly generate sensitivities tuned to the relief variations of objects of broadly varying depths. Experimental results are presented to illustrate the feasibility of the proposals.