Voxel-Based Lithography for Custom Ophthalmic Lens Fabrication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for fabricating ophthalmic lenses, such as cast molding, are limited in customizing the size and shape of lenses to specific patient needs or purposes, as the design is constrained by the mold used.
Innovation Solution
The use of a Voxel-based lithography method that exposes a reactive mixture to actinic radiation, allowing for the formation of lenses with multiple voxels and layered volumes of crosslinkable material, enabling the creation of customized lenses with optical quality surfaces and features like troughs or elevated areas, and allowing for both spherical and non-spherical shapes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If cast molding techniques are used to fabricate ophthalmic lenses, then the manufacturing process is simple and efficient, but the design of the lens is limited to the mold utilized and cannot be customized to specific patient needs
Solution Approach 1:
The lens is divided into multiple voxels (volume elements) that can be independently controlled during polymerization. Each voxel can be selectively cured or left uncured, allowing complex custom designs to be built up from simple unit structures. This segmentation enables customization without requiring a completely new mold design.
Solution Approach 2:
The traditional mechanical mold-based fabrication process is replaced with a photopolymerization process using actinic radiation. Instead of physically shaping material with molds, the lens is formed by selectively polymerizing crosslinkable material in a reactive mixture using light exposure patterns, enabling digital customization of lens design.
2Shape
If traditional mold-based fabrication is used, then the manufacturing process is straightforward, but the lens design is constrained by the physical mold and cannot achieve free-form custom shapes
Solution Approach 1:
The fabrication process transitions from two-dimensional mold surfaces to three-dimensional voxel control. By controlling polymerization in the third dimension (depth into the reactive mixture), the system can create complex free-form shapes and curved surfaces that would be difficult to achieve with traditional two-dimensional molding techniques.
Solution Approach 2:
The system controls multiple parameters during polymerization including wavelength of actinic radiation, exposure time, intensity, and spatial pattern to precisely control where and when polymerization occurs. This multi-parameter control enables precise customization of lens shape, thickness, and optical features.
3Adaptability or versatility
If voxel-based lithography with multiple rays of actinic radiation is used, then customized lens shapes and optical features can be created, but the fabrication process becomes more complex
Solution Approach 1:
The polymerization process uses periodic or sequential exposure to multiple rays of actinic radiation. Instead of requiring all rays to be active simultaneously, the system can cycle through different radiation patterns, exposing different portions of the reactive mixture at different times, which reduces the total fabrication time while maintaining customization capability.
Solution Approach 2:
The system can pre-position or pre-expose certain portions of the reactive mixture before final polymerization. By performing preliminary actions such as partial polymerization or positioning of material layers before the main fabrication process, the overall fabrication time is reduced while still achieving the final customized lens design.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enables the production of customized ophthalmic lenses with precise control over the polymerization process, allowing for the creation of lenses that can be tailored to individual patient needs and specific optical requirements, overcoming the limitations of traditional molding techniques.
Implementation Method 1
A Reactive Mixture including a photoabsorptive component is exposed to source of actinic radiation... Each ray of actinic radiation can be reflected towards a predetermined portion of the reactive mixture
Implementation Method 2
the actinic radiation is controllable to cure a portion of the Reactive Mixture in a predefined pattern... polymerized crosslinkable material... polymerized above a gel point
Implementation Method 3
a second portion with a layered volume of crosslinkable material polymerized above a gel point
Data Source
AI summary
This invention provides for an ophthalmic lens with at least one portion of the lens including multiple voxels of polymerized crosslinkable material. In addition, the present invention provides for apparatus for generating an ophthalmic lens with at least one portion including multiple voxels of polymerized crosslinkable material. In some embodiments, an ophthalmic Lens includes a surface with one or both of a raised area and a depressed area.