Interference cancellation analysis of output spectrum of virtual image phased array (VIPA) and application of VIPA in spontaneous Brillouin backscattering measurement

Abstract

This paper mainly introduced a VIPA-based Brillouin spectroscopy technology, analysed VIPA in principle, deduced a convenient Brillouin frequency shift calculation equation, analysed the output spectral characteristics of VIPA through simulation, and proposed the most simple and effective way to avoid interference cancellation in the spectrum. Finally, a single stage VIPA spontaneous Brillouin backscattering system was built, and the standard sample water was measured many times. The results are consistent with the theoretical values reported in other literatures that verified the accuracy of the theory in this paper and the stability of the system.