Optical Eye Modelling for Myopia Control

Myopia is posing a big threat to the global eye health and putting the young generation in danger of blindness. To prevent the development of high myopia, optical lenses have been developed based on the findings that the peripheral optical properties of the eye can affect myopia progression. As the core for many applications in myopia control, a realistic eye model should be established that reproduces the optical and structural features of the human eye. Based on the ocular data obtained from the recent measurement technologies, this thesis investigates the peripheral optical features of the ocular components and develops new models to achieve a more realistic description of the human eye for the wide visual field. As the most complex component in the eye model, a new crystalline lens model is proposed in Chapter 2 to represent the structural and functional features of the lens of children. The model has the capability of involving most parameters measurable on the in vivo human lens, while maintaining realistic values of optical power and spherical aberration. Starting from the lens model proposed in Chapter 2, Chapter 3 develops a method for evaluating the peripheral refracting properties of the lens. The impacts of the lens structural parameters to the peripheral lens power are systematically evaluated. Specifically, the contribution of the gradient refractive index structure to the peripheral lens power has been revealed. In Chapter 4, a fast computation method based on generalized ray tracing is developed to analyze the peripheral optical power of the cornea defined in a similarly way as proposed in Chapter 3. The method is tested on the realistic corneal model constructed from measurement data. The contribution of the cornea to the ocular refractions over the entire visual field can be formulated based on the proposed procedure. Chapter 5 and 6 investigates the role of the retinal contour to the peripheral optical properties of the eye. Specifically, a highly efficient method is proposed that can reproduce the peripheral spherical equivalent refraction over the entire visual field by retinal contour modeling. Overall, this work contributes a theoretical framework and knowledge base on the peripheral optics of the human eye, which are instrumental for developing potential approaches aimed for higher efficacy in myopia control.