An Iterative Deflectometry Method of Reconstruction of Separate Specular Surfaces

TY - JOUR

T1 - An Iterative Deflectometry Method of Reconstruction of Separate Specular Surfaces

AU - Liu, Cheng

AU - Liu, Jianhua

AU - Xing, Yanming

AU - Ao, Xiaohui

AU - Shen, Hongda

AU - Yang, Chunguang

N1 - Publisher Copyright: © 2025 by the authors.

PY - 2025/3

Y1 - 2025/3

N2 - Phase measuring deflectometry (PMD) plays a more and more significant role in the measurement of specular surfaces. However, most of the deflectometric methods are only suitable for continuous specular surfaces, but not for the discontinuous surfaces. In this work, with the hardware of stereoscopic PMD, a mechanism is introduced so that a specular surface can be reconstructed iteratively with the pre-known coordinate of a reflecting point. Based on the mechanism and the excellent local properties of the B-spline surface, a reconstruction method suitable for both kinds of specular surfaces is proposed. Meanwhile, to resist the noise of the single point, this work mathematically analyzes the mechanism of the method. With the mathematical conclusion, the sparse point cloud solved using stereoscopic PMD is employed to scale the B-spline surfaces, improving the accuracy of reconstruction. Simulated and actual experiments are carried out, and the results show high accuracy and robustness of the PMD system and the reconstruction method.

AB - Phase measuring deflectometry (PMD) plays a more and more significant role in the measurement of specular surfaces. However, most of the deflectometric methods are only suitable for continuous specular surfaces, but not for the discontinuous surfaces. In this work, with the hardware of stereoscopic PMD, a mechanism is introduced so that a specular surface can be reconstructed iteratively with the pre-known coordinate of a reflecting point. Based on the mechanism and the excellent local properties of the B-spline surface, a reconstruction method suitable for both kinds of specular surfaces is proposed. Meanwhile, to resist the noise of the single point, this work mathematically analyzes the mechanism of the method. With the mathematical conclusion, the sparse point cloud solved using stereoscopic PMD is employed to scale the B-spline surfaces, improving the accuracy of reconstruction. Simulated and actual experiments are carried out, and the results show high accuracy and robustness of the PMD system and the reconstruction method.

KW - B-spline surface

KW - deflectometry

KW - separate specular surfaces

KW - stereoscopic PMD

UR - https://www.scopus.com/pages/publications/86000594438

U2 - 10.3390/s25051549

DO - 10.3390/s25051549

M3 - Article

AN - SCOPUS:86000594438

SN - 1424-8220

VL - 25

JO - Sensors

JF - Sensors

IS - 5

M1 - 1549

ER -