Share Email Print
cover

Optical Engineering • Open Access

Phase error elimination considering gamma nonlinearity, system vibration, and noise for fringe projection profilometry
Author(s): Jun Yao; Xiong Chen; Yihao Zhou; Hong Miao; Jubing Chen

Paper Abstract

Fringe projection profilometry (FPP) using a digital video projector is widely used for three-dimensional shape measurement. However, the gamma nonlinearity, system vibration, and noise cause the captured fringe patterns to be nonsinusoidal waveforms and have a grayscale deflection from their true value. This leads to an additional phase measurement error for a general phase-shifting algorithm. Based on the theoretical analysis, we propose a method to eliminate the phase error considering two factors. In this method, four-step phase-shifting is done four times with an initial phase offset of 22.5 deg and the average of these four phase maps precisely results in the real phase. As a result, phase error caused by gamma nonlinearity can be effectively suppressed. In addition, every image in phase shifting is replaced by the average of 20 fringe images continuously captured at the same state to avoid the phase error caused by system vibration and noise. Experimental results show that this method is effective in eliminating the phase error in practical phase-shifting FPP. In general, more than 90% of the phase error can be reduced.

Paper Details

Date Published: 24 September 2014
PDF: 7 pages
Opt. Eng. 53(9) 094102 doi: 10.1117/1.OE.53.9.094102
Published in: Optical Engineering Volume 53, Issue 9
Show Author Affiliations
Jun Yao, Shanghai Jiao Tong Univ. (China)
Xiong Chen, Univ. of Science and Technology of China Club (China)
Yihao Zhou, Shanghai Jiao Tong Univ. (China)
Hong Miao, Univ. of Science and Technology of China (China)
Jubing Chen, Shanghai Jiao Tong Univ. (China)


© SPIE. Terms of Use
Back to Top