提高膜片式F-P腔光纤压力传感器灵敏度的试验研究

膜片式F-P腔光纤压力传感器是基于法布里-珀罗干涉原理,采用微电子机械系统(MEMS)技术加工而成。在实际应用中,不同的测试环境对传感器灵敏度的要求各不相同,如果针对不同灵敏度,分别采用MEMS工艺批量化生产,则会造成生产成本过高,经济化效益降低。本文利用湿法腐蚀的方法对传感器进行膜片减薄试验,在一定范围内提高了传感器的压力灵敏度,从而满足了不同的测试需求。膜片减薄后,传感器的灵敏度可达34.2 nm/kPa,压力标定曲线的线性度为0.9997,传感器的非线性误差为0.05%,能够实现0~120 kPa(绝压)范围内压力的准确测量。

Research on Improvement of Sensitivity of Diaphragm Type Optical Fiber Pressure Sensors Based on F-P Cavity Interference

The fiber optic pressure sensors based on Fabry-Perot （ F-P ） interferometric principle are fabricated by employing the micro-eletromechanical system （ MEMS） . In practical application, different sensitivities are required in different testing environments. The cost of pro-duction will be excessive if the sensors are fabricated by MEMS with different sensitivities. In this paper, the thickness-reduction of the diaphragm in sensors is discussed, and the pressure sensitivity is improved within certain limits through the wet-etching. The sensitivity reached 34.2 nm/kPa after the reduction of the diaphragm thickness. The result of the pressure calibration shows that the linearity of the curve is 0.9997, and the non-linear error reaches 0.05% in the range of 0-120 kPa （ absolute pressure） .