Bragg grating-based laser sensors systems with interferometric interrogation and wavelength division multiplexing

We describe the use of fiber Bragg grating based lasers as sensors. An interferometric detection technique is presented for interrogating laser wavelength shifts due to measurand induced laser cavity strain with high resolution from both single-mode and multimode lasers. The principle of integrating multiple sensors to form an array is demonstrated using a wavelength division multiplexing approach.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>