付立叶变换轮廓术中参数的优化选择

OPTIMIZED CHOICE OF ARGUMENTS IN FTP

利用等效波长的概念对ＦＴＰ（付立叶变换轮廓术）测量方法中的参数θ与载频ｆ０进行优化选择，保证了付立叶频谱中各级谱的完全分离与系统测量精度．运用空间带宽积的概念，实现了对ＦＴＰ测量系统中若干参数（如测量范围、探测器成象系统放大倍数、探测器的抽样频率、投影光栅空间频率）的最高允许值进行选择与限制．计算机模拟的结果验证了理论上的推导．

With the conception of equivalent wavelength,the authors are albe to make better choices of arguments θ and f 0.By doing so,the authors can ensure the complete separation of all the spectra in frequency domain and the measuring precision of system.The authors also realized the choice and restraint of some arguments in FTP measuring system,such as measuring range,imaging magnification of detective system,sampling frequency of detective,the max permitted space frequency of the projected grating pattern,by using the conception of space bandwidth product.The result was confirmed by the computer simulation experiments.