Tilted Fiber Bragg Gratings (TFBGs) Temperature Sensing Element Using 244nm AR+ Laser Written on Side Hole Fiber

Abstract

Tilted Fiber Bragg Gratings (TFBGs) are designed and implemented at the 1550 nm communication window in Institute of Optoelectronic Technology, China Jiliang University, Hangzhou, China. They are experimentally demonstrated to work as high sensitive temperature sensing element. The tilted fiber Bragg gratings of 10 mm were written on the core of 7-cm and 26-cm hydrogen loaded side hole fibers using 244 nm frequency doubled 488 nm Argon ion laser based on phase mask technique. The transmission spectrum of the first TFBG sensing element showed two resonant dips at 1579.614 nm and 1582.502 nm respectively. The transmission spectrum of the second TFBG sensing element showed two resonant dips at 1579.108 nm and 1580.304 nm. The achieved sensitivity is about 10 pm / °C. To the best of our knowledge our finding regarding setup with low cost is very close to the performance of other types of Fiber Bragg Gratings (FBGs) (1).