马赫-曾德光纤干涉光谱测量系统的设计

光纤干涉光谱仪由于其体积小、分辨率高、抗电磁干扰和耐高温的特点，广泛应用于各种领域的物质检测中。设计了一种使用电动光纤延迟线实现光程差调制的基于Mach-Zehnder光纤干涉仪的光谱测量系统。介绍了系统的构成，推导了基于该系统的光谱计算公式以及分辨率计算公式。搭建了实验平台，对一宽谱光源进行测试，并采集其干涉信号，解调出了相应的光谱图。对结果进行分析，当最大光程差变为0.479 5 cm时，光谱分辨率为2.085 4 cm-1。电动光纤延迟线的性能在很大程度上决定了最终解调出的光谱的分辨率、精度，尤其是速度和延时时间的精度和线性度。

Design of spectrum measurement system based on Mach-Zehnder optical fiber interference

Optical fiber interference spectrometer is widely used in various fields of substance detection, because it has many characteristics such as small size, high resolution, anti-electromagnetic interference, high temperature resistance, etc. A spectrum measuring system based on Mach-Zehnder optical fiber interferometer is designed, which uses an electric optical fiber delay line to modulate the optical path difference.System constitution is introduced, spectrum calculation formula and spectral resolution calculation formula are deduced.Then experimental platform is setup, and a light source with wide spectrum is measured by the system, interference signal is collected and its spectrogram is demodulated.Results show the spectral resolution is 2.085 4 cm-1, when the maximum optical path difference is 0.479 5 cm. Analysis on the system shows that, performance of the optical fiber delay line, to a great extent, determines the resolution, accuracy and precision of the final demodulation spectrum, especially the accuracy of the speed and the delay time, and the linearity.