Title :
An improved low temperature sensing using PMMA coated FBG
Author :
Sengupt, D. ; Shankar, M. Sai ; Reddy, P. Saidi ; Prasad, R. L N Sai ; Narayana, K.S. ; Kishore, P.
Author_Institution :
Dept. of Phys., Nat. Inst. of Technol., Warangal, India
Abstract :
Fiber Bragg Gratings have been shown to have a much improved thermal sensitivity when coated by Polymethyle methacrylate (PMMA) at cryogenic regime has been proposed. The PMMA has large thermal expansion coefficients and acts as driving elements. It is coated on the FBG at room temperature and the FBG is under compression at lower temperatures. This allows a much wider tuning of Bragg grating as fiber can stand at more compression than tension. An overall sensitivity of 0.039nm/K in the 1550nm wavelength regime has been achieved and the Bragg wavelength has been tuned upto 8.97nm in the temperature range 77K to 303K.
Keywords :
Bragg gratings; fibre optic sensors; low-temperature techniques; optical fibres; optical polymers; optical tuning; temperature sensors; thermal expansion; Bragg wavelength; FBG; PMMA; compression; cryogenics; fiber Bragg gratings; low temperature sensing; polymethyle methacrylate; room temperature; sensitivity; temperature 293 K to 298 K; temperature 77 K to 303 K; tension; thermal expansion coefficients; thermal sensitivity; wavelength 1550 nm; Abstracts; Heating; Optical sensors; Strain; Substrates; Thermal expansion; Bragg grating; Low temperature sensitivity; PMMA coating; Strain;
Conference_Titel :
Communications and Photonics Conference and Exhibition, 2011. ACP. Asia
Conference_Location :
Shanghai
Print_ISBN :
978-0-8194-8961-6
