High-quality binary fringe patterns generation by combining optimization on global and local similarity

Feng Lu,Chengdong Wu,Jikun Yang

doi:10.1186/s41476-018-0081-0

Abstract

BackgroundThe recently proposed optimized dithering techniques can improve measurement quality. However, the objective function in these optimization methods just qualifies the global similarity of the pattern while the global optimization methods ignore the influences of local structure.MethodIn order to get high quality binary dithered patterns, this paper presents an algorithm which combines optimization on global and local similarity and implements it in the whole-fringe optimization.ResultsBoth the simulation and experimental results demonstrate that the proposed algorithm can achieve binary fringe patterns with higher phase quality and less intensity difference. The fringe patterns based on the proposed method can get high quality measurement results.ConclusionThe proposed method can get high quality binary dithered patterns under different defocusing levels by combining global similarity and local structure similarity. The proposed method can improve the robustness to the amounts of defocusing.

Highlights

The recently proposed optimized dithering techniques can improve measurement quality
In order to contain the local similarity in the objective function, we propose a weighted synthetic function (WSF)
The measurement quality is determined by phase quality of the binary dithering fringes

Summary

Introduction

The recently proposed optimized dithering techniques can improve measurement quality. Digital fringe projection (DFP) techniques based on sinusoidal fringe patterns have been widely used for high-quality 3D shape measurement due to their flexibility and speed [1]. There are major limitations of the conventional DFP technique: high speed measurement (i.e., typically 120 Hz) and projection nonlinearity, which make it difficult to be applied to high-speed measurement [2]. To overcome these limitations, two categories of methods are proposed: the 1-D pulse width modulation methods [3, 4] and the 2-D area modulation methods [5, 6]. Some researchers have developed the dithering techniques to make

Methods

Results

Conclusion