基于光子晶体光纤和单模光纤错芯结构的光纤传感器

A fiber sensor based on the core-offset structure of PCF to SMF

制作了一种基于光子晶体光纤(PCF)和单模光纤(SMF)错芯结构的全光纤传感器。实验中,采用5cm的PCF,将其两端分别与SMF错芯熔接,制成传感单元。第1个错芯结构将宽带光源的光分别耦合到PCF的纤芯和包层中,纤芯模式和包层模式经过一定传输距离后进行SMF的纤芯,满足相位条件的发生干涉。在光谱仪(OSA)中观测其干涉谱。当外界温度、折射率变化时,观测干涉峰位置的改变可实现对温度和折射率的传感。实验结果显示,本文光纤传感器对温度的灵敏度为-8×10-3 nm/℃,对折射率的灵敏度为102nm/RIU。对PCF填充乙醇后,制成相同结构的传感器,温度灵敏度达到-1.008nm/℃,提高了123倍。本文传感器制作简单,操作方便,能够广泛应用于生物和物理传感领域。

A fiber sensor based on photonic crystal fiber（PCF）and core-offset structure is proposed.It is manufactured by splicing PCF and single mode fiber（SMF）.Transmitting through the core-offset structure,the light is coupled into the core and cladding of PCF.The modes of core and cladding interfere when the phase condition is achieved.The dips of transmission spectrum can be used to measure the variations of temperature and refractive index.Experimental results show that temperature sensitivity and refractive index sensitivity are-8×10^-3 nm/℃ and 102nm/RIU,respectively.Then alcohol is filled into the PCF and the sensor with the same structure is manufactured.Experimental results show that the temperature sensitivity reaches-1.008nm/℃,which improves by 123 times.The sensor has the advantages of easy fabrication and simple operation,and it can be widely applied in biological and physical sensing fields.