Talbot moire deflectrometry with direct spatial reconstruction of optical phase

Improvements in Talbot-moire deflectometry are presented. A Talbot-moire interferometer, using a laser diode as light source, a single grating and a CCD camera, placed in one of the Talbot planes, was set-up. The computer yields a moire pattern by mixing the acquired Talbot image of the first grating with the reference generated by computer or stored as an undisturbed external grating Talbot image. For moire pattern processing, direct spatial reconstruction of optical phase, in spatial and Fourier domains, implemented in a high-level image processing language (IDL TM ), was employed. The theoretical limit of the relative error of Talbot-moire deflectometry was verified by measuring the focal length of a lenticular system with controlled-focal- length.