Development of a new 3D educational eye model to understand refractive errors, their detection, and correction

Abstract

This work introduces a three-dimensional (3D) model of the human eye, designed for educational and outreach purposes in the fields of optics and optometry. Created using the online software Tinkercad, the model aims to enhance the understanding of key concepts such as image formation, refractive errors, and their correction. The model is constructed with proportions similar to those of the human eye and includes the main optical elements: a lens simulating the cornea, another representing the crystalline lens (with options for spherical, cylindrical, or accommodative components), an interchangeable pupil, and a detection screen to visualize images formed on the retina. Unlike traditional two-dimensional demonstrators, this model allows for exploration in a three-dimensional environment, improving comprehension of phenomena such as astigmatism, retinal image inversion, and the impact of object position and corrective lenses. Additionally, it features an external support in the form of glasses, enabling the simulation of optical correction using real ophthalmic lenses. The model has been utilized in workshops with secondary and high school students, proving its effectiveness in sparking interest in optics, optometry, and vision. It has successfully demonstrated concepts such as retinal image inversion, accommodation, off-axis astigmatism, and the functioning of optometric tests like the clock dial test. Furthermore, it has been used to introduce advanced concepts such as the point spread function (PSF) and the Scheiner method. In summary, this 3D model offers an accessible, versatile, and effective tool for teaching the process of image formation in the human eye, benefiting both students of optics and optometry and the general public through scientific outreach.