3D shape measurement using axial lateral parallel optical interferometry

Abstract

Axial lateral parallel optical interferometry obtains a X-Z interference image using diffracted light as the reference beam and a linear illumination beam without any scan. By scanning a sample mechanically, 300 interference images were measured using an InGaAs camera (320x256 pixels, 60 frames/s, 1.05-ms exposure). 3D shape of a sample was obtained by performing the subtraction of the DC image, which was an averaged interference image, from each interference image, a high-pass filter for the axial direction and the Hilbert transform.