Single function crystalline lens capable of mimicking ciliary body accommodation.

Area of Science:

• Ophthalmology
• Biomedical Optics
• Computational Biology

Background:

• The human eye lens is optically complex due to its aspherical surface and gradient refractive index (GRIN).
• Existing lens models often treat shape and refractive index separately, requiring complex optimization for imaging properties.

Purpose of the Study:

• To develop a single, physiologically realistic GRIN model of the human lens.
• To simultaneously describe the lens shape and refractive index distribution across different accommodative states.
• To integrate this model into a schematic eye for simulating accommodation and image quality.

Main Methods:

• A novel, single-function model was developed to represent the entire lens, incorporating GRIN properties.
• A single parameter, linked to ciliary body function, was used to adjust accommodative states.
• The model was implemented in a schematic eye using experimental biometric data, simulating accommodation from 0 to 6 diopters.

Main Results:

• The model accurately describes lens shape and refractive index distribution during accommodation.
• Simulated changes in lens thickness and aberrations during accommodation fall within reported experimental ranges.
• Optimal image quality levels were identified through accommodation simulation.

Conclusions:

• The proposed GRIN lens model offers a simple yet highly accurate representation of the human eye's optical system.
• This model facilitates realistic simulation of accommodation and its impact on image quality.
• The findings contribute to a better understanding of ocular optics and potential vision correction strategies.