High resolution Moiré contouring by a hybrid technique combining light and electron optics

Abstract

A technique for measuring the form of small objects is presented. The process is similar to conventional Moiré contouring but, by combining the advantages of light and electron optics, the problem of obtaining a large depth of field and high resolution is overcome. The technique is applied to the measurement of a Rockwell diamond indenter, using a scanning electron microscope to form height contours over a field diameter of 800 μm and to a depth of 200 μm. Qualitative results are presented and the expected accuracy of subsequent microprocessor aided, quantitative metrology is predicted.