基于三种不同微腔状态的F-P干涉型高灵敏度温度传感器

High Sensitivity Fabry-Pérot Interferometric Temperature Sensor Based on Three Different Microcavity States

设计了一种基于法布里-珀罗干涉结构的温度传感系统。分别利用空气、蒸馏水、5%NaCl溶液、无水乙醇、甲醇以及有机硅橡胶作为传感器的温度敏感材料,以提高温度灵敏度。实验结果表明,当腔内介质为空气时,F-P干涉结构的温度灵敏度与腔长成反比;而当液体材料作为腔内介质或固体材料作为F-P型检测探针时,腔的长度几乎不会影响结构的温度灵敏度,因为此时波长漂移的主要原因是材料热光系数的改变,温度灵敏度与材料的热光系数成正比。实验中,甲醇作为热光系数绝对值最高的液体,充满法布里-珀罗腔时温度灵敏度为-564 pm/℃,而固化后的有机硅橡胶直接作为法布里-珀罗型检测探针时温度灵敏度可高达1.15 nm/℃。该温度传感结构具有体积小、重复性好、灵活可塑性强等优点,在温度传感领域具有潜在的应用价值。

A temperature sensing system based on the Fabry-Pérot interference structure is designed.Air,distilled water,5%NaCl solution,absolute ethanol,methanol and cured silicon rubber are used as the temperature sensitive materials of the sensor to improve the temperature sensitivity effectively.The experimental results show that when the medium in the cavity is air,the temperature sensitivity of the F-P interference structure is inversely proportional to the cavity length.However,when the medium in the cavity is liquid or the solid material constitutes F-P type detection probe,the length of the cavity will hardly affects the temperature sensitivity of the structure.Because at this time the main reason of the wavelength shift is the change of material’s thermo-optical coefficient,the temperature sensitivity is proportional to it.In the experiment,methanol is the liquid with the highest absolute value of the thermooptical coefficient.And when it is filled with F-P cavity,the temperature sensitivity is-564 pm/℃.In addition,when the cured silicone rubber is used as an F-P type detection probe directly,the temperature sensitivity can be as high as 1.15 nm/℃.The temperature sensing structure has the advantages of small size,good repeatability,strong flexibility and plasticity,and has potential application values in the field of temperature sensing in the future.