Two-Wavelength Single-Shot Interferometry

Abstract

A new surface profiling technique is proposed, which enables us to measure a surface profile without losing high frequency components of sharp edges and with extended phase measurement range. It is accomplished by a newly developed two-wavelength imaging system and the local model fitting (LMF) algorithm for carrier fringe pattern analysis. The experimental results demonstrated that the proposed method can measure steep steps fast and accurately with an extended measurement range, while the robustness against vibration in the conventional single-shot methods is maintained.