基于低相干光的光子晶体光纤熔点背向反射测量

光子晶体光纤(PCF)与传统单模光纤熔接时斜切熔接可以大大减小熔点处反射,但是仍然存在微弱的残余背向反射,为了精确测量该残余背向反射大小,本文基于低相干光干涉测量原理提出了一种Mach-Zehnder与Michelson混合型干涉仪。基于该干涉仪,对包层直径125μm实芯光子晶体光纤与传统单模光纤斜8°熔点,以及包层直径100μm实芯光子晶体光纤与传统单模光纤斜8°熔点处的背向反射进行了测量,得到背向反射率分别为-52.12 d B和-49.35 d B,并获得了熔点的位置信息。该干涉仪为光子晶体光纤斜切熔点残余背向反射的精确定位和测量提供了工具和手段,为熔点质量的改善奠定了基础。

Measurement for back-reflection of photonic crystal fiber fusion splicing point based on low-coherence light

Although angle-cleaved fusion splice can greatly reduce the reflection of the fusion splicing point between photonic crystal fiber (PCF) and conventional single mode fiber,a weak residual back-reflection still exists at the fusion splicing point.A Mach-Zehnder and Michelson hybrid interferometer based on the principle of low-coherence interferometry was designed to achieve accurate positioning measurement of the residual back-reflection.Utilizing the interferometer,a-52.12 dB back reflectance of the 8° oblique splicing point between 125 μm cladding diameter solid-core PCF and conventional single mode fiber and a-49.35 dB back reflectance of the 8° oblique splicing point between 100 μm cladding diameter solid-core PCF and conventional single mode fiber were obtained.The locations of the two fusion splicing points were also acquired.The interferometer provides tools and means for precise positioning and measurement of the residual back-reflection of PCF angle-cleaved fusion splicing point,and lays a foundation for the quality improvement of the fusion splicing point.