Loss peak adjustment of long period fiber grating fabricated with CO₂ laser by applying tension

Abstract

This study aims to propose a method for adjusting loss peak in the spectrum of long period fiber grating fabricated with CO₂ laser by applying tension with some weight to make the loss peak suitable for a multi-point temperature sensor under a high temperature environment. This method could achieve an increase of 5.3 dB in the value of loss peak by loading the fiber with a weight of 150 g. Furthermore, it was found that the method had a minimal influence on the temperature sensitivity of the long period fiber grating in the range varying from room temperature to 800°C.