Modal content of living human cone photoreceptors

摘要: Decades of experimental and theoretical investigations have established that photoreceptors capture light based on the principles optical waveguiding. Yet considerable uncertainty remains, even for most basic prediction as to whether support more than a single waveguide mode. To test modal behavior in human cone near infrared, we took advantage adaptive-optics coherence tomography (AO-OCT, λc = 785 nm) noninvasively image three dimensions reflectance profile cones. Modal content reflections generated at inner segment outer junction (IS/OS) tip (COST) was examined over range diameters 1,802 cones from 0.6° 10° retinal eccentricity. Second moment analysis conjunction with predictions indicate IS OS properties consistent waveguides, which depend diameter refractive index. Cone found mode fovea (≤3°) multiple modes further away (>4°). In contrast, no evidence OSs. The IS/OS COST share common aperture, are circular fovea, show orientation preference, temporally stable. We tested conventional step-index fiber model order fit our AO-OCT results required lower estimate index introduction an focusing/tapering effect.