Photon Trajectory in the Human Cornea

TL;DR

This paper introduces the Trajectron algorithm to accurately model photon trajectories in the human cornea's gradient refractive index, enabling precise analysis of non-paraxial light bending with implications for refractive surgery.

Contribution

The paper presents the first quantitative method for non-paraxial intra-corneal light-bending analysis using a novel Trajectron algorithm based on closed-form solutions.

Findings

Demonstrates non-paraxial intra-corneal light-bending phenomena

Provides a new tool for refractive surgery algorithm development

Improves accuracy over previous paraxial models

Abstract

In this article, we follow the trajectory of a photon in the human cornea. Prior to experimental evidence of the cornea's gradient refractive index (GRIN) nature, schematic eye models used a constant or average as the corneal refractive index. A few recent models respect the intra-corneal GRIN, but are based on the paraxial approximation, and thereby have limited validity in peripheral visual field analysis and non-paraxial photon tracking. Here, we introduce the Trajectron algorithm. It uses a closed form solution of the ray equation of constant axial GRIN media, and evaluates over piece-wise constant GRIN. Using Trajectron, we present the first quantitative demonstration of non-paraxial intra-corneal light-bending phenomena. This demonstration has significant implications in the development of refractive surgery algorithms.