Wavelength/frequency-division multiplexing of heterodyning fiber grating laser sensors with the assistance of CO_2-laser treatment

摘要

In this paper, we demonstrate the implementation of a 1×10 array of heterodyning fiber grating laser sensors, pumped by a single 980 nm laser diode. The sensors are wavelength-multiplexed by inscribing fiber gratings with different periods and frequency-multiplexed in the RF domain with the assistance of CO_2-laser treatment. Through the side irradiation from the CO_2 laser, the intra-cavity birefringence can be significantly changed and the output frequency of the individual lasers can be continuously adjusted. The frequency range that can be achieved is as much as 1.5 GHz. As a result, the multiplexing capability of this kind of sensor is greatly improved.