Improved intensity-optimized dithering technique for 3D shape measurement

The recently proposed optimized dithering techniques are able to improve measurement quality obviously. However, those phase-based optimization methods are sensitive to the amount of defocusing while intensity-based optimization methods cannot reduce the phase error efficiently. This paper presents a novel method, minimizing a proposed objective function named intensity residual error (IRE), as well as a novel framework, optimizing pixels group by group, to construct binary patterns for high-quality 3D shape measurement. Both the simulation and experimental results show that this proposed algorithm can achieve phase quality improvements over other recently optimized dithering techniques with various amounts of defocusing. (C) 2014 Elsevier Ltd. All rights reserved.