摘要
首次提出了一种基于U型波导耦合的新型单微环结构湿度传感器,该传感器以聚酰亚胺（polyimide,P1）作为感湿材料,当外界环境相对湿度变化时,引起感湿部位折射率的相应变化,导致传感器的输出光谱发生漂移。根据传输矩阵法推导U型波导耦合单微环结构的传递函数,重点讨论了不同感湿部位对输出光谱的影响,通过Matlab理论仿真,确定以U型波导耦合单微环结构整体作为最佳感湿部位。当U型波导的两个耦合点间的距离为微环周长的整数倍时,相比于传统的单微环结构,自由光谱范围（FSR）实现加倍。外界相对湿度从10%RH变化到100%RH时,传感器的输出光谱漂移量在0.027~0.191μm之间变化,灵敏度高达0.001 8μm/%RH,相比于具有高灵敏度的光纤光栅类湿度传感器,灵敏度提高了10~100倍,实现了在高灵敏度感湿的同时兼顾谐振峰两侧大范围的滤波选频。
The paper proposes a novel high sensitivity humidity sensor based on a U-shaped waveguide-coupled single micro-ring, Polyimide is used as the wet material, the refractive index of humidity-sensing part changes as relative humidity changes, thus leading to a obvious peak drift. The transfer function of the structure is derived basing on transfer matrix method and the paper mainly discusses the influence on the output spectrum with different humidity-sensing parts. Through the theoretical simulation of Matlab, the whole structure of U-shaped waveguide coupled single micro-ring is proved to be the best humidity-sensing part. The free spectral range （FSR） will be doubled compared to the traditional single micro ring structure while the length between the two coupling points of the U-shaped waveguide is an integer multiple of circumference of the micro-ring. When the relative humidity of external environment changes from 10 %RH to 100%RH, the output spectrum appears a obvious drift from 0. 027 to 0. 191 tLm and the sensitivity reaches up to 0. 001 8 μm/%RH. Compared to FBG humidity sensor with high sensitivity, the sen- sitivity in this article is increased by 10 to 100 times, achieving a high sensitivity in the sense of humidity when the wide range of filter frequency selection is taken into account.
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2015年第2期563-567,共5页
Spectroscopy and Spectral Analysis
基金
国家自然科学基金项目(60877047
61172044)
河北省自然科学基金项目(F20100002002)资助
关键词
U型波导耦合单微环结构
传输矩阵法
湿度传感器
灵敏度
FSR
U-shaped waveguide-coupled single micro-ring structure
Transfer matrix method
Humidity sensor
Sensitivity
FSR
