Slices method to describe ray propagation in inhomogeneous media

We describe an alternative method that numerically calculates the trajectory followed by a light ray in rotationally symmetric inhomogeneous media in the paraxial approximation. The medium is divided into thin parallel slices and a radial quadratic refractive index is considered for each slice. The ABCD matrix is calculated in each slice and the trajectory of the ray was obtained. The method is demonstrated considering media with a refractive index distribution used to describe the human eye lens. The results are compared with the exact numerical solution for each particular distribution. In all cases, a good agreement is obtained for the proposed method and the exact numerical solution.