Beveled fiber-optic probe couples a ball lens for improving depth-resolved fluorescence measurements of layered tissue: Monte Carlo simulations

In this study, we evaluate the feasibility of designing a beveled fiber- optic probe coupled with a ball lens for improving depth- resolved fluorescence measurements of epithelial tissue using Monte Carlo ( MC) simulations. The results show that by using the probe configuration with a beveled tip collection fiber and a flat tip excitation fiber associated with a ball lens, discrimination of fluorescence signals generated in different tissue depths is achievable. In comparison with a flat- tip collection fiber, the use of a large bevel angled collection fiber enables a better differentiation between the shallow and deep tissue layers by changing the excitation - collection fiber separations. This work suggests that the beveled fiber- optic probe coupled with a ball lens has the potential to facilitate depth- resolved fluorescence measurements of epithelial tissues.