Zenodo · May 19, 2026
Age-Dependent Geometric-Energy Refraction Model: Extended Nature-Style Article with Figures
By yildirim B
Human vision arises from a multilayered optical system involving the cornea, crystalline lens, aqueous humour, vitreous media, and finally the retinal mosaic. While classical geometric optics provides a macroscopic description, increasingly detailed retinal imaging has revealed age-dependent optical deviations that conventional Snell-based models cannot capture. Young eyes display highly stable, symmetric optical signatures, whereas elderly eyes show heterogeneous alterations in retinal sharpness, contrast distribution, and microvascular visibility. This motivates a refined model that incorporates corneal differential geometry, curvature-derived geometric energy, and a Laplacian-energy correction term. Additionally, optical performance is known to degrade or diversify with age due to biomechanical changes in corneal elasticity, lens stiffness, and microstructural scattering. Accordingly, age-dependent coefficients must be introduced into the refraction model to describe the continuum from stable youth to heterogeneous aging. Here, we develop an age-dependent geometric-energy refraction framework and validate it using fundus images from the TREND database. Our central claim is that curvature-energy and Laplacian effects generate observable differences in retinal imaging, and that these effects become significantly modulated—and more individualised—with aging. Originality and AI-use statement: This work is an original research output by Begüm Yıldırım. AI tools, if used, were limited to language refinement, grammar correction, formatting, translation assistance, and clarity improvement. The conceptual framework, research direction, interpretation, models, and conclusions belong to the author. External sources, datasets, or prior works are cited where applicable.