光纤温湿度传感器功率响应与涂覆层厚度关系

Relationship between power response and thickness of coating layer of optical fiber temperature / humidity sensor

采用了一种基于光强度调制的双包层单模光纤温湿度传感器,对其结构特性和工作机理进行研究;根据光波导理论推导出了双包层光纤的模式场分布情况与特征方程;在传感器的制作过程中,对光纤的腐蚀工艺、温湿度敏感材料的选择、涂覆方法等作出实验分析。实验研究表明:敏感材料的涂覆厚度对传感器的光功率输出响应范围和线性度具有很大的影响,需要控制好涂覆层的厚度,以达到理想的光强调制深度和响应线性度。

A double cladding single-mode fiber temperature/humidity sensor based on light intensity modulation is adopted and its structure characteristics and working mechanism are studied. According to optical waveguide theory, mode field distribution and characteristic equation of double cladding fiber are deduced. Corrosion technology of optical fiber, choice of temperature/humidity sensitive material and coating methods are experimentally analyzed. It is found that coating thickness of sensitive materials has great influence on range and linearity of light power output response, so it needs to control thickness of coating layer, in order to achieve ideal modulation depth of light intensity and response linearity.