Figure 1: Simulation of light guiding by human Müller cells.

(a) Schematic representation of Müller cells (M) and photoreceptors organization in the human parafoveal retina. Müller cells' (in black) proximal cup-like funnel of ~12 μm in diameter, covers ~15 rods in addition to the central cone. Nerve fibre layer (NFL), and inner nuclear layer (INL) are outlined. (b) A data cube of 1,000 × 256 × 256 grid containing a Müller cell (of 130 μm length) and its surrounding tissue was reconstructed, based upon measured indices of refraction profile (scale on the right). (c,d) Simulation of light passing through a single Müller cell (top) and the corresponding distribution at the distal part of the cell (bottom), for an incident light of 430 nm (blue) and 560 nm (green–yellow). Light concentration into the centre (cone’s receptive field) is higher for the green than for the blue. (e) The transmitted spectrum into the central cone is calculated by summing the pixels inside the Müller cell’s area, and averaged over the last longitudinal intensity cycle. The peak transmission is at 560 nm, corresponding for the green-yellow part of the visible spectrum.