基于正弦结构光相移法的高效精确投影仪校准方法

Efficient and accurate projector calibration method based on phase-shifting method with sinusoidal structured light.

作者信息

Li Wenguo, Zhong Yongpeng, Liu Tao, Tai Manli

机构信息

Faculty of Mechanical & Electrical Engineering, Kunming University of Science & Technology, Kunming, 650500, China.

出版信息

Heliyon. 2023 Mar 31;9(4):e15067. doi: 10.1016/j.heliyon.2023.e15067. eCollection 2023 Apr.

DOI:10.1016/j.heliyon.2023.e15067

PMID:37095954

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC10121812/

Abstract

OBJECTIVE

Projector calibration is one of the most basic and important steps in structured light three-dimensional measurement. However, such as complicated calibration process and low accuracy are still the inevitable problems in the calibration process. In this paper, a projector calibration method based on phase-shifting method with sinusoidal structured light is proposed to improve the accuracy of the calibration and simplify the operation of the calibration.

METHODS

Firstly, projecting a set of sinusoidal fringes onto a black-and-white circular calibration board, and collecting the images synchronously by a CCD camera; Secondly, establishing the correspondence between camera pixels and projector pixels by using the consistency of phase information which means that the absolute phase value of an arbitrary point on the calibration board is equal to the absolute phase value of this point in the camera image and virtual projector image; And then a set of virtual DMD images on the projector can be obtained by using the principle above; Finally, using this set of virtual DMD images, the parameters of the projector can be calibrated with camera calibration method based on circular calibration board.

RESULTS

The experimental results show that the maximum reprojection error of the projector calibrated by this method is 0.0419 pixels, and the average reprojection error is 0.0343 pixels. The equipment involved in the calibration process is simple and the experimental operation is easy. The experimental results indicated that this method has high calibration accuracy and efficiency.

摘要

目的

投影仪校准是结构光三维测量中最基本且重要的步骤之一。然而，校准过程中诸如复杂的校准流程和低精度等问题仍是不可避免的。本文提出一种基于正弦结构光相移法的投影仪校准方法，以提高校准精度并简化校准操作。

方法

首先，将一组正弦条纹投影到黑白圆形校准板上，并用电荷耦合器件（CCD）相机同步采集图像；其次，利用相位信息的一致性建立相机像素与投影仪像素之间的对应关系，即校准板上任意一点的绝对相位值等于该点在相机图像和虚拟投影仪图像中的绝对相位值；然后，利用上述原理可获得投影仪上的一组虚拟数字微镜器件（DMD）图像；最后，使用这组虚拟DMD图像，基于圆形校准板的相机校准方法对投影仪参数进行校准。