3D Printing of Multimaterial Contact Lenses for Ophthalmic Applications

Abstract

The concept of smart multifunctional contact lenses has attracted immense attention in recent years. Smart multifunctional contact lenses can simultaneously perform various functionalities like vision correction, health monitoring, and drug delivery. However, the production of such multifunctional lenses is highly challenging. There are no standard processes for producing smart multifunctional contact lenses. Complex processes like chemical vapor deposition, etching, and laser ablation are often used in multiple steps to produce a single multifunctional lens. The complexity of the production process leads to increased costs, which makes them unaffordable and uneconomical. 3D printing processes can be useful for overcoming the current difficulties in their production. The layer-by-layer production strategy of 3D printers offers a great deal of flexibility. 3D printing also provides the benefit of easy customization. Vat photopolymerization is the most suited 3D printing process for contact lenses due to its high resolution, low cost, and capability to print hydrogels. Recently, a few studies have explored the 3D printing of simple single material contact lenses. However, the production of multimaterial contact lenses has not been explored. Multimaterial 3D printing processes have emerged recently with the ability to deposit multiple materials in different regions of the printed object. However, there have not been studies that explore the use of multimaterial 3D printing of optical devices like contact lenses. This thesis explores the use of multimaterial vat photopolymerization 3D printing for the production of multifunctional contact lenses. Contact lenses were printed with the primary functionality of color vision correction. Functionalities of UV protection, monitoring of ocular pH, and temperature are also explored. Color vision correction was incorporated through the addition of wavelength-filtering Atto dyes. Multimaterial 3D printing enabled the deposition of multiple dyes in different sections of a single lens. The resulting multimaterial lens was compared with commercial color vision correction glasses. The challenges in multimaterial 3D printing, like material change interface and material change in the x-y plane, were explored in detail, and methods to overcome these challenges were identified. Multiple techniques were identified for the application of multimaterial 3D printing for contact lenses: pause and material change, re-attaching a 3D printed single material contact lens to buildplate and printing functionalized structures on its surface, and 3D printing functionalized components on a commercial contact lens. Multifunctional contact lenses that simultaneously incorporate four different functionalities were also produced. It is expected that this study will pave the way toward the inexpensive production of smart multifunctional contact lenses.

Date of Award	5 May 2025
Original language	American English
Supervisor	HAIDER BUTT (Supervisor)