根据相似性准则,对采集到的干涉图像进行干涉图元的拆分,通过寻址定位,得到与离散光程差序列相匹配的采样干涉图序列。采用过零采样方式,对大单边干涉图序列与小双边干涉图序列利用不同的窗函数进行切趾。为了校正相位误差,结合所研究采样干涉图的特点,对频域光谱乘积校正和空域干涉图卷积校正进行了研究和改进,获得了比较理想的光谱线形,其中空域干涉图卷积校正后的光谱偏差仅为0.012088,具有最好的校正效果。
The sampling mode of static Fourier transform spectrometer is spatial domain sampling.The interferogram function is sampled by two orthogonal stepped mirrors and the interference irradiance is received by the detector.The interferogram image is a planar spatial array which consists of M×M interferogram units.After image segmentation,the interferogram image is divided into M×M interferogram units according to comparability criterion.By means of addressing location,the sampled interferogram sequence which matches up to the discrete optical path difference sequence could be gained.Using over-zero sampling technique,the big single side interferogram sequence and the small double side interferogram sequence are apodizated by different window functions.For the sake of correcting phase error,the frequency-domain spectrum correction and space-domain interferogram correction are researched and improved.The simulation result shows that the two methods can both gain the perfect spectrum line shape,and the effect of space-domain interferogram correction is better than others with the spectrum standard deviation only 0.012 088.