To model the light-guiding properties of a hexagonal array of dielectric cylinders, we have numerically solved Maxwell's equations with the finite-difference time-domain technique. The sizes and refractive indices of the cylinders are representative of those of the outer segments of the cone photoreceptors in the human central retina. In the array, light propagates predominantly as a “slow” mode, with a noticeable contribution of a “fast” mode, with the optical field localized in the intra- and inter-cylinder spaces, respectively. Interference between these modes leads to substantial (up to approximately 60%) axial oscillations in optical power within the cylinders. Our numerical model offered approximate dependence of the optical intensity distribution within the cylinders on their radii and separations.
This paper was published in [Journal of the Optical Society of America A : optics, image science, and vision] and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: [http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-27-4-865]. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law.