Polyvinyl alcohol coated photonic crystal optical fiber sensor for humidity measurement
Wong, Wei Chang
Chan, Chi Chiu
Chen, Li Han
Lee, Kok Xian
Leong, Kam Chew
Date of Issue2012
School of Chemical and Biomedical Engineering
A polyvinyl alcohol (PVA) coated photonic crystal optical fiber (PCF) sensor has been proposed as a relative humidity (RH) sensor. It was fabricated by collapsing the holes of PCF at both ends to form a Michelson interferometer with cladding mode excitation. PVA was dip coated onto the sensor and the interference shift was measured when the sensor was exposed to varying RH. The sensor with 9% (w/w) coating showed a high sensitivity of 0.60 nm/%RH, displayed little hysteresis, high repeatability, low cross-sensitivity to temperature and ammonia gas and stability over 7 days of testing. A rise/fall time of 300/500 ms was achieved respectively.
Sensors and actuators B: chemical
© 2012 Elsevier B.V.