High-speed phase-shifting profilometry under fluorescent light. (May 2020)

• Record Type: Journal Article
• Authors: Zheng, Dongliang; Kemao, Qian; Han, Jing; Wang, Jing; Yu, Haotian; Bai, Lianfa
• Is Part Of: Optics and lasers in engineering. Volume 128(2020)
• Publication Date: 2020-05
• Subjects: Phase-shifting profilometry -- Fluorescent light -- Phase error suppression; Lasers in engineering -- Periodicals; Optical measurements -- Periodicals; Optics -- Periodicals; Lasers en ingénierie -- Périodiques; Mesures optiques -- Périodiques; Optique -- Périodiques; 621.36605
• DOI: 10.1016/j.optlaseng.2020.106033
• Languages: English
• ISSNs: 0143-8166

Abstract

Highlights: This is the first time to discover and describe the fluorescent light problem, but was totally ignored in phase-shifting profilometry. The fluorescent light problem could be serious especially for high-speed phase-shifting profilometry and generates the phase error up to 0.12 rad. A fluorescent light error suppression algorithm is proposed, which can reduce the phase error to a comparable level with system noise of 0.02 rad. Abstract: Phase-shifting profilometry (PSP) has been widely used in three-dimensional (3-D) shape measurement because of its attributes of high-accuracy and high-resolution. However, PSP typically works under fluorescent light, flickering with a double frequency of the alternating current frequency, which may generate a non-ignorable phase error, and result in a PSP's measurement error, especially for PSP using a high sampling speed. We first mathematically describe the fluorescent light problem, model the PSP's phase error, and state the problem in high-speed PSP. Next, a fluorescent light error suppression (FLES) algorithm is proposed to suppress the phase error. Both the phase error model and the proposed algorithm are theoretically analyzed, and then numerically and experimentally verified. The provided numerical and experimental results coincide with the theoretical analysis. The proposed algorithm can reduce the phase error from 0.12 rad to a comparable level with system noise of 0.02 rad, which is significant for the accurate measurement of 3-D shapes for high-speed PSP in a fluorescent light environment.