投影栅相位法三维检测的频域相对解相技术  

Relative phase demodulation technique in frequency domain in projected grating phase method

作　　者：许庆红[1] 钟约先[1] 由志福[1] 

机构地区：[1]清华大学机械工程系,北京100084

出　　处：《清华大学学报（自然科学版）》2000年第4期8-10,20,共4页Journal of Tsinghua University(Science and Technology)

摘　　要：为提高投影栅相位法在三维检测实际应用中的解相精度 ,分析了频谱混叠及移频方法的不准确对解相精度造成的影响 ,建立了一种新的频域相对解相技术。基于小波变换得到相对栅线图像 ,其频谱中背景成分基本消除 ,有利于有用频带的提取。同时 ,通过计算两幅图像的相对位相 ,避免了单幅图像移频方法所带来的系统误差。实例证明该技术改善了解相的精度和稳定性 。Precision of phase demodulation in practical 3D detection using the projected grating phase method was improved by recognizing that spectrum mixing and inaccurate frequency moving greatly affected the accuracy of phase demodulation. A new relative technique in the frequency domain was then developed to improve the accuracy. The relative distorted grid image obtained using wavelet transform was used to remove the background components in the spectrum to obtain the desired spectrum. The systematic errors from the frequency moving with one image have been eliminated by calculating the relative phase of two images. Expereice has shown that the new technique can improve the precision and the stability of phase demodulation with the projected grating phase method.

关 键 词：投影栅相位法 三维检测 解相 频域 小波变换 

分 类 号：O348.12[理学—固体力学]