Light-Sheet Skew-Ray Enhanced Pump-Absorption for Sensing

Abstract

We present a new sensing technique exploiting light-sheet excitation of skew rays in a multimode fiber, which can be applied to enhance the sensitivity of a range of sensing mechanisms such as pump absorption. The underlying principle is that a light sheet (i.e., thin plane of light) can selectively concentrate the optimum ray group, giving rise to enhanced interaction between light and matter (e.g., fluorophores). We compared this excitation method with others in terms of attenuation of pump light through Rhodamine B. It was observed that the attenuation experienced by light-sheet skew rays can be up to one order of magnitude higher than that of collimated skew rays, and three orders of magnitude higher than that of normal-incidence rays.