准相干干涉法测量光纤群折射率

介绍了用准相干干涉法测量光纤群折射率的方法。通过准相干干涉定位 ,用精密光栅数显系统测长 ,由计算机采集并处理数据获得一段短光纤的光学长度 ,然后利用常规精密测长手段测得其几何长度 ,从而得到光纤的群折射率。实验结果及误差分析得出 :测量不确定度优于 7× 10 -5(2σ)。

Measurement of group refractive index of fibers using semi-coherent interference

The measurement of group refractive index of fibers using semi coherent interference is introduced. The optical length of a short fiber is acquired firstly by a measurement system, which consists of a semi coherent interferometer, precise grating length measuring unit, and a computer used to acquire and process the data. After the geometrical length of the fiber under test is measured by the conventional method, its group reflective index can be determined. The results of the experiment and error analysis give the measurement uncertainty of 7×10 -5 (2 σ ).