A real-time response relative humidity sensor based on a loop microfiber coated with polyvinyl alcohol film. (January 2022)

• Record Type: Journal Article
• Authors: Sun, Dandan; Chen, Jiguang; Fu, Yongming; Ma, Jie
• Is Part Of: Measurement. Volume 187(2022)
• Publication Date: 2022-01
• Subjects: Loop microfiber interferometer -- Polyvinyl alcohol (PVA) -- Relative humidity (RH) sensor -- Good stability; Weights and measures -- Periodicals; Measurement -- Periodicals; Measurement; Weights and measures; Periodicals; 530.8
• DOI: 10.1016/j.measurement.2021.110359
• Languages: English
• ISSNs: 0263-2241

Abstract

Highlights: A loop microfiber with polyvinyl alcohol film for measuring relatively humidity. The sensor has high sensitivity, fast response, and low temperature influence. Sensitive materials are low-cost, nontoxic, and environmentally friendly. The proposed sensor provides a better choice for relatively humidity detection. Abstract: A high sensitivity optical fiber loop-based relative humidity (RH) sensor coated with polyvinyl alcohol (PVA) film is demonstrated, which has low-temperature sensitivity. The loop region of the sensor (micron-sized diameter) is very sensitive to the environmental medium due to strong evanescent fields out of fiber cladding. The refractive index (RI) sensitivity is as high as 2979 nm/RIU, while the temperature sensitivity is relatively low at 0.0075 nm/°C. The experimental results show that the sensor has the RH sensitivity of 0.533 nm/%RH (wavelength modulation) and −0.213 dBm/%RH (intensity modulation). The proposed sensor has good real-time, stability and repeatability, which provides a guarantee for accurate RH measurement.