Penetration depth of focused beams in highly scattering media investigated with a numerical solution of Maxwell's equations in two dimensions.

The propagation of different focused beams (e.g., Gaussian or quasi-Bessel beams) through scattering media is studied. The finite-difference time-domain method, a numerical solution of Maxwell's equations, is applied to propagate the light beams in two dimensions. The focused beams are modeled by applying the angular spectrum of the plane waves method. The results show that weakly focused beams exhibit comparable performance to strongly focused beams in delivering focused light deep into scattering media.