Off-axis Anti-reflective Intraocular Lens Coating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Intraocular lenses (IOLs) often cause unwanted reflective phenomena such as glare, halos, and ghost images due to off-axis light reflections, which are cosmetically undesirable and can affect visual performance, especially in individuals with larger pupils.

Innovation Solution

Applying a dual-layer anti-reflective coating with specific refractive indices and thicknesses to reduce off-axis light reflections, while minimizing adverse effects on axial light transmission, using materials with refractive indices between 1.46 and 1.60, and applying the coating to the entire lens surface or peripheral regions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If an intraocular lens is implanted to correct vision, then vision correction is achieved, but off-axis light reflections cause unwanted visual phenomena such as glare, halos, and ghost images

Engineering Contradiction:
Improvevision correctionVSAvoidoff-axis light reflections
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

A dual-layer anti-reflective coating is applied to the intraocular lens surface. The first layer has a refractive index between 1.46-1.56 and the second layer has a refractive index between 1.36-1.46. These intermediate refractive index layers act as mediators between the lens material and the surrounding medium, reducing off-axis light reflections by an order of magnitude while maintaining vision correction functionality.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the optical parameters of the lens surface by applying coatings with specific refractive indices (1.46-1.56 for the first layer, 1.36-1.46 for the second layer) and specific thicknesses (65-85 nm for the first layer, 45-85 nm for the second layer). These parameter changes reduce off-axis reflections while minimizing impact on axial light transmission.

Inventive Principle:
Principle #35Parameter changes

2Object-generated harmful factors

If an anti-reflective coating is applied to reduce off-axis reflections, then visual disturbances are minimized, but the coating complexity increases

Engineering Contradiction:
Improvevisual disturbancesVSAvoidcoating structure
Core Design Contradiction:
Object-generated harmful factorsVSDevice complexity

Solution Approach 1:

Instead of using a complex multi-layered or nanostructured anti-reflective coating, the patent achieves effective reflection reduction by precisely controlling the refractive index and thickness parameters of just two layers. The first layer has refractive index 1.46-1.56 and thickness 65-85 nm, while the second layer has refractive index 1.36-1.46 and thickness 45-85 nm. This parameter-based approach simplifies the coating structure while maintaining effectiveness.

Inventive Principle:
Principle #35Parameter changes

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

The dual-layer coating reduces off-axis light reflections by an order of magnitude, enhancing wearer acceptance and visual performance by minimizing ghost images and other visual disturbances.

Implementation Method 1

a first anti-reflective coating layer (520) having a refractive index n1 that is less than the IOL lens body's refractive index nIOL... A second anti-reflective coating layer (530) is layered over the first anti-reflective coating layer (520), and the second anti-reflective coating layer (530) has a refractive index n2 less than the refractive index n1 of the first anti-reflective coating layer (520)

Methodology Applied
Scientific EffectOptical interference: Interference

Implementation Method 2

the first anti-reflective coating layer (520) has a thickness t1 in a range from about 65 nm to about 85 nm... the second anti-reflective coating layer (530) has a thickness t2 in a range from about 45 nm to about 85 nm

Methodology Applied
Scientific EffectRefraction: Refraction

Data Source

PatentEP2166986B1Off-axis Anti-reflective intraocular lenses
Publication Date: 2016.03.30 NOVARTIS AG
  • EP2166986B1 patent drawingFigure 1~2
  • EP2166986B1 patent drawingFigure 3~5
  • EP2166986B1 patent drawingFigure 6

AI summary

Exemplary embodiments provide a coated intraocular lens (400) that has a lens body (410) with a first refractive index and an anti-reflective coating (420). The coating covers at least a portion of the lens body and has a second index of refraction that is less than the first index of refraction of the lens body. The anti-reflective coating reduces the intensity of reflections produced from off axis light incident on the lens body by at least a factor of 2.5 times and enhancing light transmission.