Fabricating micro fiber Fabry-Perot sensor with femtosecond laser pulses

Based on femtosecond laser inscription technology, a novel method for femtosecond laser micromachining system is proposed to fabricate a microfiber Fabry-Perot(F-P) cavity on the fiber end surface. This technique can solve the parallelism problem of the traditional fiber F-P sensors inscribed by femtosecond laser. The F-P interferometric sensor made by the proposed technique shows over 20 dB fringe visibility. This technique is parameter-controllable and easy to implement. It is a promising candidate of strain measurement in the case of extreme temperature circumstances.