相位高度的显函数模型及其标定

由于传统的相位轮廓术(PMP)使用的相位高度模型参数存储空间大,标定计算成本高,本文由绝对相位与深度坐标的关系推导出相位差高度模型的显函数模型,并提出了一种基于未知标定平面的灵活标定方法。该模型只需9个非共线的像素数据即可计算出模型的15个参数,降低了计算量,节约了内存空间。提出的标定方法无需精密运动台,标定板无需覆盖整个测量范围,无需知道位置姿态,降低了标定成本,提高了标定的灵活性。对提出的模型和标定方法分别进行了仿真和实验,仿真结果验证了相位高度显函数模型的正确性和标定方法的有效性。对提出的模型和标定方法在实际的结构光系统中进行了实验,用标定后的系统对实际物体进行了测量,结果表明三维曲面具有较高的质量,证明了提出方法的可行性。

Explicit phase height model and its calibration

As the phase height model in traditional Phase Measuring Profilometry(PMP)has a larger storage space and higher calibration cost, this paper deduces an explicit function model of phase difference height according to the relationship between absolute phase and depth coordinate, and proposes a flexible calibration method based on unknown calibration plane. The model can calculate 15 model parameters only by 9 nonlinear pixel data, so it saves the memory space and reduces the computing cost. The proposed calibration method does not need any movement platform and position posture, and brings the advantage of small calibration board and well flexible ability. The simulation and experiment on the model and calibration method are performed. The simulation results verify the validity of explicit function model of phase difference height and the availability of the proposed calibration method. Moreover, an actual experiment for the model and the calibration method is done in a structure light system. The calibrated system is used to test a real objective, and the results show that the 3D curved surface has higher quality, which demonstrates the proposed method is feasibility.