摘要
为了提高条纹投影偏折法对自由曲面的测量精度，通过分析投影到待测面的条纹光强变化形式，推导出一种可以免疫光强变化的五步移相算法，并通过频域傅里叶分析论述了该算法的可行性。数值实验结果表明，免疫光强变化的五步移相算法在基准光强变化1％～5％，杂散光噪声为0．1％～0．5％的情况下，相位计算精度峰值为0．0042λ，均方根值为0．0014λ，在消除离焦影响后，相位计算精度可以达到0．00092。与其他移相算法的对比分析，进一步说明了该算法的优势，免疫光强变化五步移相算法在利用条纹投影偏折法测量自由曲面领域有着较高的应用价值。
In order to improve the accuracy of projected fringe deflectometry （PFD） in measuring the free-form surface, a standard intensity insensitive five-step phase-shifting algorithm in PFD test is proposed by analyzing the change patterns of the intensity on the tested surface. Fourier techniques are used to analyze the feasibility of the algorithm. The result of the computer simulation indicates that the peak value of phase retrieve precision of the proposed algorithm is 0. 0042~ and the root mean square value is 0. 0014;t with 1% ~5 % change in standard intensity and 0.1% ~0.5 % stray noise. After removing defocus, the precision of phase retrieve is 0. 0009;t. By comparing with other phase-shifting algorithms, the performance of the algorithm manifests the advantages. As a result, the standard intensity insensitive five-step phase-shifting algorithm has a high application value in the measurement of free-form surface in PFD.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2013年第11期203-209,共7页
Chinese Journal of Lasers
基金
国家科技重大专项(2009ZX02205)
关键词
光学检测
移相算法
条纹投影偏折法
光强变化
optical measurement~ phase-shifting algorithm
projected fringe deflectometry
intensity change
