Fiber optic evanescent wave humidity sensor based on SiO2/TiO2 bilayer films

被引：17

作者：

Huang, Xixi ^{[1
,2
,3
]}

Lai, Min ^{[1
,2
,3
]}

Zhao, Ziming ^{[1
,2
,3
]}

Yang, Yang ^{[1
,2
,3
]}

Li, Jinze ^{[1
,2
,3
]}

Song, Huatang ^{[1
,2
,3
]}

He, Jixiang ^{[1
,2
,3
]}

Ma, Yan ^{[1
,3
,4
]}

Liu, Bo ^{[2
,3
]}

机构：

[1] Nanjing Univ Informat Sci & Technol, Jiangsu Collaborat Innovat Ctr Atmospher Environm, Nanjing 210044, Peoples R China

[2] Nanjing Univ Informat Sci & Technol, Jiangsu Key Lab Optoelect Detect Atmosphere & Oce, Nanjing 210044, Peoples R China

[3] Nanjing Univ Informat Sci & Technol, Sch Phys & Optoelect Engn, Nanjing 210044, Peoples R China

[4] Nanjing Univ Informat Sci & Technol, NUIST Reading Acad, Nanjing 210044, Peoples R China

来源：

APPLIED OPTICS | 2021年 / 60卷 / 08期

基金：

中国国家自然科学基金;

关键词：

RELATIVE-HUMIDITY; FAST-RESPONSE; SENSITIVITY; TEMPERATURE; FABRICATION; RESISTANCE;

D O I：

10.1364/AO.416286

中图分类号：

O43 [光学];

学科分类号：

070207 ; 0803 ;

摘要：

A SiO2/TiO2 bilayer thin-film-based fiber optic humidity sensor was fabricated via a modified dip coating process with enhanced sensitivity. SiO2 film was coated on the surface of the fiber core, followed by deposition of the TiO2 layer on SiO2. The relative humidity (RH) is measured by modulation in intensity of the transmitted laser at room temperature. The optical fiber humidity sensor based on SiO2/TiO2 film shows two-segmented linearity in measurement with sensitivities of 5.35 and 1.94 mu W/% RHat 15%-50% RHand 50%-95% RH, respectively. The response time and recovery time are 25 s and 50 s, respectively. To our knowledge, the superior response time and recovery time of the sensor in our study were achieved over those fiber optic humidity sensors reported with modulation in intensity. Furthermore, this fiber optic humidity sensor has a good reproducibility and long-term stability. The sensing mechanism is attributed to effects of moisture on the refractive index and the light absorption coefficient of SiO2 film and modulation in the transmission characteristic of evanescent waves in the optical fiber. (C) 2021 Optical Society of America

引用

页码：2158 / 2165

页数：8