中圖分類號： TN204
文獻標識碼： A
DOI：10.16157/j.issn.0258-7998.191411
中文引用格式： 巫濤江，趙雅，趙杰，等. 一種準確測量溫濕度的光纖Bragg光柵傳感器[J].電子技術應用，2020，46(6)：68-72.
英文引用格式： Wu Taojiang，Zhao Ya，Zhao Jie，et al. A fiber Bragg grating sensor for accurate measurement of temperature and humidity[J]. Application of Electronic Technique，2020，46(6)：68-72.

A fiber Bragg grating sensor for accurate measurement of temperature and humidity

Abstract： To accurately measure the temperature and humidity in the elevator car, a simple fiber Bragg grating(FBG) temperature and humidity sensor was developed. The sensor was composed of FBG with a grating length of 20 mm, where in the region with a grating length of 12 mm was etched to 7.8 μm by wet etching, and a polyimide moisture sensitive material was coated on the etched surface to measure relative humidity. The unetched 8 mm FBG was used to detect temperature. In the experiments, firstly, the response characteristics of the etched and unetched FBGs to the temperature and humidity were studied. Secondly, the influence of the thickness of the polyimide film on the humidity response of the etched FBG was examined. Thirdly, the response of the etched FBG with polyimide coating to temperature was checked. Fourthly, we investigated the response of the sensor that includes etched and unetched FBGs in variable temperature and humidity environment. The experimental results show that when the thickness of the humidity sensitive film was 80 μm, the response sensitivity of the etched FBG to humidity was 17.1 pm/(%RH). The sensitivity of the unetched FBG to temperature was 9.9 pm/℃. The sensor can accurately measure temperature and humidity in the temperature range of 30 to 70 ℃ and in the humidity range of 20~90%RH.

Key words : temperature and humidity；polyimide；fiber Bragg grating；accurate measurement；sensitivity