Abstract

This paper describes the fabrication, sensitivity characteristics, transducer design and multiplexing of heterodyning sensors based on dual-frequency DBR lasers. The laser naturally emits output with two polarizations modes with a frequency difference as a result of the intrinsic birefringence, and can be applied as photonic sensors by monitoring the beat frequency. The heterodyning sensor presents intrinsic sensitivities to transverse load, magnetic field and ultrasonic signals, and can be exploited to measure a number of perturbations inlcuding accelaration, acoustic wave, and hydrostatic pressure with enhanced sensitivities through transducer design. The laser sensors can be multiplexed in both wavelength and frequency domains towards large-scale applications. Compared with other existing sensing schemes, the DBR heterodyning sensor is a promising approach which simultaneously presents advantages including high measurement resolution/sensitivity, low demodulation cost, and the multiplexing capability.

© 2014 Optical Society of America