基于LabVIEW的光纤傅里叶变换光谱仪数据处理技术

Data processing technique for optical-fiber Fourier transform spectrometer based on Lab VIEW

为了提高编程效率与增强光谱仪数据分析处理能力,结合LabVIEW软件在信号处理方面的优势,利用虚拟仪器技术实现了光纤傅里叶变换光谱仪干涉图处理与光谱复原。采用均匀抽样算法,利用由光纤Mach-Zehnder干涉仪输出的参考光干涉图过零点取样,实现对测试光干涉图的等光程间隔采样,消除了由压电陶瓷非线性光程调制引起的误差。采用求摸法复原出光谱图,自动消除了相位误差。利用LabVIEW软件完成了对宽带ASE光源的干涉图数据采集、显示与处理并最终得到光谱图。结果表明,与光栅光谱仪测得的光谱相比,光谱线型趋于一致。

To improve programming efficiency and data analyzing and processing capability in spectrometer, considering the advantages of LabVIEW in signal processing,we have realized interferogram processing and spectrum reproduction of fiber Fourier transform spectrometer using virtual instrument technology.Uniform sampling algorithm is used.Reference light interferogram produced by optical-fiber Mach-Zehender interferometer is sampled using zero crossing sampling to accomplish equal optical path interval sampling of the interferogram of the test light.Thus,the nonlinear error induced by the nonlinear modulation of piezoelectric ceramic is eliminated. The spectrogram is reconstructed using modular multiplication algorithm to eliminate phase error automatically. Data acquisition,display and processing of the interferogram produced by broadband light source ASE are completed using LabVIEW software.The spectrogram is obtained finally.Result demonstrates that the spectrum-line shape tends to be uniform compared with that obtained using grating spectrometer.