Passive Temperature-Compensating Technique for Microstructured Fiber Bragg Gratings

TL;DR

This paper presents a passive temperature compensation method for microstructured fiber Bragg gratings by filling their holes with a suitable liquid, significantly reducing thermal drift and enhancing sensing accuracy.

Contribution

It introduces a novel passive compensation technique using liquid infiltration into MOF holes, reducing thermal sensitivity of FBGs.

Findings

Spectral variation divided by a factor of 4

Maximum sensitivity significantly reduced

Effective for temperature ranges over 20°C

Abstract

The thermal drift of the characteristic wavelength of fiber Bragg gratings (FBGs) photowritten in the core of microstructured fibers (MOFs) is significantly reduced by inserting a liquid of suitable refractive index into their holes. For instance, the spectral range of variations is divided by a factor of 4 over a temperature range larger than 20\degree C in a six-hole MOF, and the maximum sensitivity is reduced. Such passive FBG temperature compensation technique is of great interest for applications involving accurate sensing free of thermal effects.