Composite High Index Layers for Ophthalmic Lens Antireflective Stacks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing antireflective stacks for ophthalmic lenses face a challenge in balancing the mean reflection factor in the UV range (Ruv) and visible range (Rv), where minimizing one often results in unsatisfactory performance in the other range.
Innovation Solution
The use of composite high index layers, specifically comprising zirconium oxide and other metal oxides like tantalum oxide and niobium oxide, in the antireflective stack, allows for simultaneous optimization of Ruv and Rv performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If the antireflective stack is designed to minimize Ruv (UV reflection), then UV protection is improved, but Rv (visible reflection) becomes too high
Solution Approach 1:
The patent uses composite high index layers combining zirconium oxide and tantalum oxide to achieve simultaneous optimization of both UV and visible range antireflective performance. This composite material approach allows tuning of optical properties to balance Ruv and Rv values, resolving the contradiction between minimizing UV reflection and maintaining acceptable visible reflection.
Solution Approach 2:
The patent modifies the refractive index parameters and composition ratios of the composite layers to achieve the desired balance between Ruv and Rv. By adjusting the proportions of zirconium oxide and tantalum oxide, as well as optimizing layer thicknesses, the design simultaneously minimizes both UV and visible reflection factors.
2Object-generated harmful factors
If the antireflective stack is designed with very low Rv (visible reflection), then cosmetic appearance is improved, but Ruv (UV reflection) becomes unsatisfying
Solution Approach 1:
The composite high index layers of zirconium oxide and tantalum oxide provide a broader and more tunable refractive index range compared to single materials, enabling the design to achieve very low Rv values while simultaneously maintaining satisfactory Ruv performance through proper composition and thickness optimization.
Solution Approach 2:
The patent applies different composite compositions and thicknesses to different layers within the antireflective stack, with each layer optimized for specific wavelength ranges. This local optimization allows the overall system to achieve low reflection across both UV and visible spectra simultaneously.
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 design of efficient antireflective stacks that achieve low Ruv and Rv values, improving eye protection against UV reflection and reducing cosmetic issues from visible light reflection, with Ruv below 2% and Rv below 1.25% for ophthalmic lenses.
Implementation Method 1
anti reflective stack which strongly reduces reflection in the UV range and in the visible range
Implementation Method 2
composite high index layers comprising zirconium oxide and another metal oxide such as tantalum oxide and niobium oxide
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
Ophthalmic lens comprising an antireflective stack which strongly reduces reflection in the UV range and in the visible range. The antireflective stack comprises composite high index layers comprising zirconium oxide and another metal oxide.