Effects of apertures on scattered light: A Monte Carlo study of confocal imaging

Abstract

A study is carried out to understand better the effect of apertures towards spatial and angular/directional dynamics of light scattered from a scattering medium at different planes of observations. Several types of aperture such as circular, semi-circular and annular aperture are considered. The investigation is done within the context of a reflectance mode confocal microscope based on a 4-f optical system. A Monte Carlo simulation method to describe the focusing and propagation of light in a turbid medium is adopted. A mechanism based on direction cosines is applied to simulate photon propagation through different planes within the microscope system. The spatial distribution and spatial frequency distribution (directional cosine) profile coupled with scattering statistics from such photonic simulations are observed and discussed.