Ceramic-coated type III femtosecond Fiber Bragg Grating for high temperature environments

Boron nitrite-based ceramic coating is developed to protect fiber Bragg gratings (FBG) for harsh environment use. Coated FBGs are manufactured. Characterization and tests are made in Air at different high temperature levels (700°C, 800°C, 900°C) during 500 hours. Long-term behavior (up to 1500 hours) is also studied at 800°C.