Ex) Article Title, Author, Keywords
New Phys.: Sae Mulli 2020; 70: 681-685
Published online August 31, 2020 https://doi.org/10.3938/NPSM.70.681
Copyright © New Physics: Sae Mulli.
Su-Jeong PARK, Young-min KO, Jong-Ju MOON, Tae-Jung AHN*
Department of Photonic Engineering, Chosun University, Gwangju 61452, Korea
A fiber-optic pulsed ultraviolet (UV) light sensor, based on a functional polymer-coated optical fiber and butt-coupling of the waveguides, is proposed. The azobenzene polymer was prepared by mixing an azobenzene compound and an UV curing agent. The polymer was applied as a coating on one of two optical fibers and aligned in an alumina fiber ferrule by using a UV curing process. This coating was reversibly stretched by UV light, and in the coated region, the UV light along the fiber induced tensile strains. The strain induced a gap variation between the fibers that resulted in a variation in the optical coupling ratio. The coupling intensity was measured using lock-in amplification to suppress the system noises. We achieved fast detection of UV light, pulsed with a time duration of 0.1 s. This sensing technique is an initial step required to monitor instantaneous UV light in a defective insulator.
Keywords: Ultraviolet sensor, Defective insulator, Fiber-optic sensors, Azobenzene material