Yuan Leiwen, Kang Jiehu, Feng Luyuan, Chen Yifei, Wu Bin
Opt Express. 2023 Jul 3;31(14):23115-23126. doi: 10.1364/OE.495388.
The crosstalk coefficient calibration of de-crosstalk in color fringe projection profilometry is an essential step for the high-accuracy measurement. In this paper, a novel approach for calibrating crosstalk matrix of color camera is proposed. The wrapped phase error model introduced by color crosstalk in orthogonal pattern is established. Compared with the existing calibration methods depending on calculating the modulation of the crosstalk channel, the crosstalk coefficients are obtained from phase error in our method. By projecting the designed color orthogonal phase-shifting fringe patterns onto a white plate, the phase-shifting fringe patterns in both horizontal and vertical directions can be separated from captured images. The coefficients between different channels are calibrated by fitting the error relationship between the wrapped phase containing crosstalk and the standard ones. Coefficient fitting simulations and experimental validations including shape measurement of a white plate and distance measurement of a step block are carried out to verify the effectiveness of the proposed method.
彩色条纹投影轮廓术中去串扰的串扰系数校准是高精度测量的关键步骤。本文提出了一种校准彩色相机串扰矩阵的新方法。建立了正交图案中彩色串扰引入的包裹相位误差模型。与现有的依赖于计算串扰通道调制的校准方法相比，我们的方法从相位误差中获取串扰系数。通过将设计的彩色正交相移条纹图案投影到白板上，可以从采集的图像中分离出水平和垂直方向的相移条纹图案。通过拟合包含串扰的包裹相位与标准相位之间的误差关系，校准不同通道之间的系数。进行了系数拟合仿真和实验验证，包括白板形状测量和台阶块距离测量，以验证所提方法的有效性。
