APPLICATION OF THIN-FILM OPTICAL FILTERS TO THE TEMPERATURE COMPENSATION OF OPTICAL-FIBER GRATING-BASED DEVICES

A major problem currently affecting the implementation of in-fiber ref ractive-index grating-based optical fiber devices is the drift in wave length modulation due to the change in the ambient temperature. For ac curate and reliable long-term operation of these devices, suitable tem perature compensation techniques are a necessity, This paper presents a novel temperature compensation technique for in-fiber refractive ind ex grating-based devices and components, The proposed technique is bas ed on the temperature-dependent spectral characteristics of a dielectr ic multilayer thin-film interference filter fabricated on the endface of refractive-index grating impressed optical fiber, Temperature compe nsation is achieved by comparing the reflected intensities at the grat ing-reflected and the interference filter-reflected wavelengths, The p roposed scheme also compensates for light source fluctuations and lead -in fiber bending losses.