Snapshot Interferometric Systems with Polarization Cameras

Abstract

Interferometry has been established as an important tool for a variety of applications, including physics, industrial manufacturing, biology, and medicine. Phase-shifting interferometry is one of the most general methods in interferometric systems for its high measurement accuracy, rapid measurement, good results for low contrast fringes, and independence of irradiance variations across the pupil. In most cases, the phase calculation error caused by environmental noise is the primary error. Comparing with temporal phase-shifting, which introduces a phase-shift sequentially, spatial phase-shifting methods that capture phase-shifted interferograms simultaneously can significantly reduce the influence of environmental noise. In this dissertation, we present several snapshot phase-shifting interferometric systems with the pixelated mask spatial phase-shifting technique using a polarization camera. As a spatial phase-shifting method, the pixelated polarization camera method has the advantages of a common path configuration, compact design, achromatic over a very wide range, and fixed spatial interference patterns, which makes it suitable for dynamic measurement. Various applications based on this technique are presented, including on-machine interferometry, single-shot multi-wavelength interferometry, snapshot quantitative phase microscopy, and freeform surface metrology. The principles and applications are theoretical analyzed and experimental demonstrated for each system.