Direct fringe projection profilometry based on the spatial frequency distribution function in optical 3D imaging

• Published in: Optics and laser technology Vol. 174; p. 110695
• Main Authors: Xu, Yongze, Yang, Jinfeng, Dong, Yanqing, Shi, Peng, Sun, Huarui
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.07.2024
• Subjects: Direct fringe projection profilometry; Spatial frequency distribution function; Without phase unwrapping; Without phase unwrapping; Direct fringe projection profilometry; Spatial frequency distribution function
• ISSN: 0030-3992; 1879-2545
• DOI: 10.1016/j.optlastec.2024.110695

Phase unwrapping has been a big hurdle in conventional optical three-dimensional (3D) measurement technologies, badly affecting speed and accuracy. To skip the complicated step of phase unwrapping, a direct fringe projection profilometry based on the spatial frequency distribution function is presented in this paper. First, the spatial frequency distribution function is defined according to the physical meaning of spatial frequency. Then, direct phase-shift method and direct Fourier transform profilometry are developed respectively with reference to the conventional fringe projection profilometry. Finally, both numerical simulations and experiments were carried out to test the proposed direct fringe projection profilometry. The direct phase-shift method without phase unwrapping combines the advantages of the conventional in terms of high accuracy, while the direct Fourier transform method does not get rid of the drawbacks of the conventional in spectral aliasing although it skips the phase unwrapping procedure. •Our research led to significant advancements in the optical 3D imaging by successfully addressing the issue of phase wrapping and eliminating the need for any phase unwrapping algorithms.•Both numerical simulations and experimental results demonstrated that the direct fringe projection profilometry offers advantages over traditional optical 3D measurement.•The proposed spatial-frequency-distribution-based optical 3D imaging method introduced novel insights into phase manipulation of light field that measuring the spatial frequency may be more direct than measuring phase.