摘要
Long-period fiber gratings have the advantages of small size,corrosion resistance,anti-electro-magnetic interference,and high sensitivity,making them widely used in biomedicine,the power industry,and aerospace.This paper develops a long-period fiber grating sensor based on periodic microchannels.First,a series of linear structures were etched in the cladding of a single-mode fiber by femtosecond laser microma-chining.Then,the laser-modified region was selectively eroded by selective chemical etching to obtain the periodic microchannel structure.Finally,the channels were filled with polydimethylsiloxane(PDMS)to im-prove the spectral quality.The experimental results show that the sensor has good sensitivity in the measure-ment of various parameters such as temperature,stress,refractive index(RI),and bending.It has a temperat-ure sensitivity of−55.19 pm/℃,a strain sensitivity of−3.19 pm/με,a maximum refractive index sensitivity of 540.28 nm/RIU,and a bending sensitivity of 2.65 dB/m^(-1).All of the measurement parameters show good lin-ear responses.The sensor has strong application prospects in the field of precision measurement and sensing.
长周期光纤光栅因具有体积小、耐腐蚀、抗电磁干扰和灵敏度高等优点,广泛应用于生物医学、电力工业以及航空航天等领域。本文研制了一种基于周期微通道的长周期光纤光栅传感器。首先通过飞秒激光微加工在单模光纤的包层中刻蚀出一系列直线结构,然后通过湿法腐蚀技术对激光改性区域进行选择性腐蚀以获得周期性微通道结构,最后在通道中填充聚二甲基硅氧烷(PDMS)以改善光谱质量。实验结果表明,该传感器可以进行温度、应力、折射率和弯曲等传感参数测量,具有良好的传感灵敏度。温度灵敏度为−55.19 pm/℃,应变灵敏度为−3.19 pm/με,最大折射率灵敏度为540.28 nm/RIU,弯曲灵敏度为2.65 dB/m^(-1),且均表现出良好的线性响应。该传感器在精密测量和传感领域有良好的应用前景。
基金
国家自然科学基金(No.62090064,No.62131018,No.62305130,No.62090063,No.62075082,No.U20A20210,No.61827821)。
