Servin M, Malacara D, Malacara Z, Vlad V I
Appl Opt. 1994 Jul 1;33(19):4103-8. doi: 10.1364/AO.33.004103.
A novel method to demodulate undersampled interferograms using a computer-stored undersampled compensator is presented. First, the sine and cosine of the computer-stored wave front is correlated with the interferogram that emerges from the asphere under test. Afterward, these two correlation images are used to find the phase map. The detected phase of the correlation fringes is the estimated phase difference between the software compensator and the frame-grabbed interferogram. The prior information required for this method is a good knowledge of the wave front being tested to a few wavelengths of error. Complying with this prior knowledge, the undersampled interferogram under analysis may be easily demodulated. Given that the proposed method is based on the correlation of the frame-grabbed interferogram and the computer-stored one, the method also withstands noise.
提出了一种使用计算机存储的欠采样补偿器解调欠采样干涉图的新方法。首先，将计算机存储的波前的正弦和余弦与从被测非球面产生的干涉图进行相关。之后，利用这两个相关图像来找到相位图。相关条纹的检测相位是软件补偿器与帧抓取干涉图之间的估计相位差。该方法所需的先验信息是对被测波前有精确到几个波长误差的良好了解。符合这一先验知识，分析中的欠采样干涉图就可以很容易地被解调。鉴于所提出的方法基于帧抓取干涉图与计算机存储的干涉图的相关性，该方法也具有抗噪声能力。
