膜片式微型F-P腔光纤压力传感器研究

对基于Fabry-Perot（F-P）干涉仪原理的膜片式微型光纤压力传感器的制作工艺进行了实验研究。在单模光纤端面上直接熔接外径约175μm的毛细石英管，在石英管的另一端制作敏感膜片，从而在光纤端面与膜片内表面之间形成F-P干涉腔。首先采用电弧熔接、切割、腐蚀膜片的方法制作了石英膜片式压力传感器，该传感器在0-3.1MPa压强范围内F-P腔的腔长变化灵敏度为41.09nm/MPa，压强测量分辨率681Pa，并具有很小的温度敏感系数。在30-140℃的温度范围内，温度交差敏感小于1.07KPa/℃。为了克服石英膜片减薄困难的缺点，选用聚合物材料（PSQ）作为压力敏感膜片制作了F-P传感器，室温下在0.1-2.1MPa压强范围内PSQ膜片的F-P腔长变化灵敏度达到 1 886.85nm/MPa,压强测量分辨率达到53Pa。

Diaphragm based miniature F-P cavity fiber optic pressure sensor

Miniature fiber optic pressure sensor based on Fabry-Perot (F-P) interferometric principle is described. A piece of hollow fiber with 175 μm out diameter is fused directly onto a ?ber tip to form an air gap for the F-P cavity. The essential pressure sensing element is a thin diaphragm which is fused onto the other end of the hollow ?ber. First, an entire quartz structure miniature fiber optic pressure sensor is fabricated by cleaving, fused splicing and etching. The pressure response of the sensor has been tested, showing a sensitivity of 41.09nm/MPa in the full pressure scale of 0-3.1MPa. The system resolution of 681Pa has been reached for the pressure measurement. The temperature sensitivity of the sensor has also been tested under atmospheric pressure, exhibiting a weak temperature dependence of 1.07KPa/℃ in the test temperature range from 20 to140℃. Since it is hard to further decrease the thickness of the quartzose diaphragm，A polymer（PSQ） diaphragm is used instead to increase the sensitivity of the sensor. The pressure response of the PSQ diaphragm based sensor has also been tested under room temperature, showing a sensitivity of 1 886.85nm/MPa, in the full pressure scale of 0.1-2.1MPa, with a system resolution of 53Pa.