高精度光纤光栅波长测试系统研究CSCD

为了准确测量光纤光栅（FBG）的中心波长,设计了一种高精度光纤光栅波长测试系统,主要由可调谐激光器和光功率计组成,采用波长扫描的方法进行测试。利用可调谐激光器输出光波长精度和信噪比高的特点,通过在光功率计的全量程范围进行波长扫描,得到高精度、大动态范围的光纤光栅反射光谱曲线,然后应用四次多项式拟合来计算中心波长。测试结果表明,系统在（1520 - 1590）nm 波长范围内,测量重复性优于0.5pm,测量不确定度为2pm（k=2）,可以满足传感用光纤光栅的测试需要。

Research on the High Precision Test System for Wavelength of FBG

In order to measure the center wavelength of Fiber Bragg Grating (FBG) accurately, a high precision test system for wavelength of FBG is designed, it mainly consists of a tunable laser and a optical power meter, the measurement is achieved by using the method of wavelength sweeping. The output of tunable laser has advantage of high wavelength accuracy and signal to noise ratio, through wavelength sweeping at full scale range of optical power meter, the high precision and wide dynamic range reflected spectrum of FBG is obtained, four polynomial fitting is then applied to calculate the center wavelength. The measurement results showed that in the wavelength range of (1 520~1 590)nm, the measurement repeatability is better than 0.5pm, the uncertainty of measurement is 2pm (k=2), it can fulfill the measuring requirement of FBG which wildly used in sensing field.