At cryogenic temperature, a fiber Bragg grating (FBG) temperature sensor with controllable sensitivity and variable measurement range is demonstrated by using bimetal configuration. In experiments, sensitivities of -51.2, -86.4, and -520 pm/K are achieved by varying the lengths of the metals. Measurement ranges of 293-290.5, 283-280.5, and 259-256.5 K are achieved by shortening the distance of the gap among the metals.
© 2009 Chinese Optics Letters
Kuo Li, Zhen'an Zhou, and Aichun Liu, "A high sensitive fiber Bragg grating cryogenic temperature sensor," Chin. Opt. Lett. 7, 121-123 (2009)