Phase error analysis and compensation for phase shifting profilometry with projector defocusing

Zheng, Dongliang; Da, Feipeng; Kemao, Qian; Seah, Hock Soon

doi:10.1364/ao.55.005721

Cited by 80 publications

(26 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…, and k 0 are also the fitting coefficients after transformation calculation in formula (20). It is concluded that there is actually a nonlinear response of order 3c in the measurement system.…”

Section: Phase Error Compensation Methods Based On Phasementioning

confidence: 99%

“…ree-Frequency with ree-Phase Shifts. e multifrequency heterodyne method usually projects sinusoidal fringe pattern sequence with multifrequency to measure the object, and then, a set of phase distribution with smaller frequency will be obtained from their heterodyne calculation [19,20]. erefore, it is necessary to select both the sinusoidal fringe with appropriate frequency and the appropriate period T 1 , T 2 , and T 3 .…”

Section: Reverse Calculation Initial Phase Methods Based Onmentioning

confidence: 99%

See 1 more Smart Citation

Gamma Precorrection and Phase Error Compensation Methods Based on Three-Frequency with Three-Phase Shift

Feng

Tang

et al. 2021

International Journal of Optics

View full text Add to dashboard Cite

Digital fringe projection measurement technology has been widely used in computer vision and optical three-dimensional (3D) measurement. Considering the phase error caused by the gamma distortion and nonlinear error, the active gamma precorrection and phase error compensation methods based on the three-frequency with three-phase shifts are designed to reversely solve the initial phase and accurately compensate phase error. On the one hand, the gamma coefficient of the measurement system depends on precoding two groups of fringe sequences with different gamma coefficients to calculate the corresponded proportional coefficient of harmonic component. On the other hand, the phase error compensation method is designed to compensate the phase error and improve the accuracy and speed of phase calculation after gamma correction. Experiments show that the proposed precalibration gamma coefficient method can effectively reduce the sinusoidal error in nearly 80 percent which only needs fewer fringe patterns. Compared with the traditional three-frequency with four-phase shift method, the proposed method not only has higher phase accuracy and better noise resistance but also has good robustness and flexibility, which is not limited to the gamma distortion model.

show abstract

Section: Phase Error Compensation Methods Based On Phasementioning

confidence: 99%

Section: Reverse Calculation Initial Phase Methods Based Onmentioning

confidence: 99%

Gamma Precorrection and Phase Error Compensation Methods Based on Three-Frequency with Three-Phase Shift

Feng

Tang

et al. 2021

International Journal of Optics

View full text Add to dashboard Cite

show abstract

“…In FPP systems that employ structured-light projectors, nonsinusoidal error can dominate as the major error. Nonsinusoidal phase errors can be satisfactorily modeled as a periodic sinusoidal function with multiple spatial frequencies of a multiple number of phase-shifting steps [31,32,33,34,35]:σϕ2=∑i=0N−1][∂ϕ∂Ii2σ2…”

Section: Literature Reviewmentioning

confidence: 99%

Absolute Depth Measurement Using Multiphase Normalized Cross-Correlation for Precise Optical Profilometry

Duong

Chen

2019

Sensors

View full text Add to dashboard Cite

In a multifrequency phase-shifting (MFPS) algorithm, the temporal phase unwrapping algorithm can extend the unambiguous phase range by transforming the measurement range from a short fringe pitch into an extended synthetic pitch of two different frequencies. However, this undesirably amplifies the uncertainty of measurement, with each single-frequency phase map retaining its measurement uncertainty, which is carried over to the final unwrapped phase maps in fringe-order calculations. This article analyzes possible causes and proposes a new absolute depth measurement algorithm to minimize the propagation of measurement uncertainty. Developed from normalized cross-correlation (NCC), the proposed algorithm can minimize wrong fringe-order calculations in the MFPS algorithm. The experimental results demonstrated that the proposed measurement method could effectively calibrate the wrong fringe order. Moreover, some extremely low signal-to-noise ratio (SNR) regions of a captured image could be correctly reconstructed (for surface profiles). The present findings confirmed measurement precision at one standard deviation below 5.4 µm, with an absolute distance measurement of 16 mm. The measurement accuracy of the absolute depth could be significantly improved from an unacceptable level of measured errors down to 0.5% of the overall measuring range. Additionally, the proposed algorithm was capable of extracting the absolute phase map in other optical measurement applications, such as distance measurements using interferometry.

show abstract

“…The similar model based on the Hilbert transform was also proposed to eliminate the phase error [ 28 ]. Zheng et al applied the above two methods to the phase error correction of BGPSP with projector defocusing [ 29 ]. In addition, a large-step phase-shifting method can be used to eliminate the non-linearity error [ 30 ].…”

Section: Introductionmentioning

confidence: 99%

Phase Error Analysis and Correction for Crossed-Grating Phase-Shifting Profilometry

Chen

2021

Sensors

View full text Add to dashboard Cite

Crossed-grating phase-shifting profilometry (CGPSP) has great utility in three-dimensional shape measurement due to its ability to acquire horizontal and vertical phase maps in a single measurement. However, CGPSP is extremely sensitive to the non-linearity effect of a digital fringe projection system, which is not studied in depth yet. In this paper, a mathematical model is established to analyze the phase error caused by the non-linearity effect. Subsequently, two methods used to eliminate the non-linearity error are discussed in detail. To be specific, a double five-step algorithm based on the mathematical model is proposed to passively suppress the second non-linearity. Furthermore, a precoding gamma correction method based on probability distribution function is introduced to actively attenuate the non-linearity of the captured crossed fringe. The comparison results show that the active gamma correction method requires less fringe patterns and can more effectively reduce the non-linearity error compared with the passive method. Finally, employing CGPSP with gamma correction, a faster and reliable inverse pattern projection is realized with less fringe patterns.

show abstract

Phase error analysis and compensation for phase shifting profilometry with projector defocusing

Cited by 80 publications

References 35 publications

Gamma Precorrection and Phase Error Compensation Methods Based on Three-Frequency with Three-Phase Shift

Gamma Precorrection and Phase Error Compensation Methods Based on Three-Frequency with Three-Phase Shift

Absolute Depth Measurement Using Multiphase Normalized Cross-Correlation for Precise Optical Profilometry

Phase Error Analysis and Correction for Crossed-Grating Phase-Shifting Profilometry

Contact Info

Product

Resources

About