设计并实验研究了一种基于机械微应变引入长周期光纤光栅(MLPFG)的横向压力传感系统。利用机械线加工技术制作周期为600μm,长度为60 mm的不锈钢压力槽板,测定了槽板对待写制光纤施加的横向压力与MLPFG谐振峰峰值之间的关系,并借助布拉格光纤光栅(FBG)搭建了高精度横向压力解调系统。实验表明,在0～60 N的范围内,压力与MLPFG透射谱深度有很好的线性关系,线性度达0.9950,灵敏度约为0.35 dB/N。保持45 N的压力20 h,MLPFG谐振峰峰值最大波动小于0.06 dB,具备良好的稳定性。采用中心波长为1542.890 nm的FBG实现了系统解调,系统灵敏度为0.12μW/N,进一步提高了检测系统的实用性。 A transverse pressure sensing system based on mechanical micro-strain introduced into long-period fiber grating (MLPFG) was designed and experimentally studied. The fabrication of stainless steel pressure plate with 600μm length and 60mm length by mechanical wire processing technique was used to measure the relationship between the transverse pressure applied by the groove plate and the peak value of resonance peak of MLPFG. With the aid of FBG (Fiber Bragg Grating) Set up a high-precision horizontal pressure demodulation system. Experiments show that there is a good linear relationship between the pressure and the depth of MLPFG transmission spectrum in the range of 0 ~ 60 N. The linearity is 0.9950 and the sensitivity is about 0.35 dB / N. Maintaining the pressure of 45 N for 20 h, the maximum fluctuation of resonance peaks of MLPFG is less than 0.06 dB, with good stability. The FBG system with 1542.890 nm central wavelength is used to demodulate the system. The sensitivity of the system is 0.12 μW / N, which further improves the practicability of the detection system.