Multi-objective strategy to optimize dithering technique for high-quality three-dimensional shape measurement*

Abstract

Dithering optimization techniques can be divided into the phase-optimized technique and the intensity-optimized technique. The problem with the former is the poor sensitivity to various defocusing amounts, and the problem with the latter is that it cannot enhance phase quality directly nor efficiently. In this paper, we present a multi-objective optimization framework for three-dimensional (3D) measurement by utilizing binary defocusing technique. Moreover, a binary patch optimization technique is used to solve the time-consuming issue of genetic algorithm. It is demonstrated that the presented technique consistently obtains significant phase performance improvement under various defocusing amounts.

A fast and precise three-dimensional measurement system based on multiple parallel line lasers

“…[10] The projected fringe is meticulously coded, the phase of the projected light fringe modulated by the surface of the object is calculated through algorithms, [11,12] and the 3D profile is restored according to the phase information. [13] Classic phase extraction algorithms include the three-step phase shift method [14] and the Fourier transform method. [15] Another measurement technique based on the principle of laser triangulation is more widely applied in the field of industrial precision measurement due to its advantages in measurement accuracy.…”