【摘要】 在数字条纹投射技术中,系统的非线性是影响投射条纹质量的主要因素,其直接导致变形条纹中出现高次谐波,从而影响系统的测量精度。提出了一种系统非线性校正的新方法,利用N阶多项式拟合代替传统的单一伽马参数表示系统的非线性关系,并依据条纹图像累积直方图匹配方法,通过迭代操作同时求得系统非线性关系和较高精度的物体位相分布。计算机模拟及实验结果表明,该方法能够有效地抑制系统非线性的影响,获得理想的物体位相分布,从而验证了该方法的可行性。更多还原

【Abstract】 The nonlinearity of the digital fringe projection system is an important influencing factor to the quality of the fringe patterns,which introduces specific higher-order harmonics in the distorted fringe patterns,and decreases the accuracy of the measurement inevitably.A novel nonlinearity correction method is proposed for fringe projection profilometry.In order to describe the nonlinearity of system,polynomial fitting is introduced instead of single gamma parameter.The coefficients of the polynomial are calculated by iterative operation to map the cumulative distribution functions of the captured fringe patterns and a standard sinusoidal signal.The phase distribution of the fringe pattern is also solved with higher accuracy.Computer simulation and experimental results show that the influence of nonlinear system is suppressed and the phase of object is measured with higher precision,which verifies the effectiveness of the suggested method.更多还原