Non-invasive precision metrology using diffraction phase microscopy and space-frequency method

Abstract

The paper proposes a high throughput and non-contact technique based on diffraction phase microscopy and space-frequency method for non-invasive measurement of displacement and displacement derivatives. The technique relies on common-path interferometric design and interferogram processing based on the windowed Fourier transform, and has inherent advantages such as high stability, good throughput, single shot operation and robustness against noise and external disturbances. The utility of the proposed technique is demonstrated for practical applications in surface metrology using experimental results.