在分析空间外差光谱仪干涉图生成及特点的基础上,提出了基于改进旋滤波的干涉图降噪方法。该方法是在干涉条纹的切线方向进行滤波,能够在不改变干涉图条纹细节的基础上减少干涉图中的随机噪声和暗斑噪声的影响。同时该方法还能有效降低平均光谱的背景噪声,提高特征光谱与背景噪声的信噪比,结果显示旋滤波方法对加入噪声前后干涉图的平均光谱背景噪声信噪比改善分别为47%和240%,能够将一些峰值较小的特征谱从背景噪声中提取出来,提高空间外差光谱技术对一些弱特征光谱的识别率。

A denoising method for interferogram was proposed based on the improved spin filtering by analyzing the production and characteristics of the interferogram of spatial heterodyne spectrometer. Filtering was carried out on tangent fringe-pattern to reduce the influences of random and dark spot noises without changing the details of fringe-pattern. In addition, the background noise of average spectrum was effectively decreased, the ratio of characteristic spectrum to background noise was increased. Results show that by using the spin filter method, the SNR of the average spectrum of interferogram is improved by 47% without noise and 240% with noise, respectively, and the characteristic spectra with small peak values can be extracted from the background noise to improve the recognition rate of spatial heterodyne spectroscopy as far as weak characteristic spectrum is concerned.