Diffractive Structure Soft Contact Lens Thickness Variation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional ophthalmic lenses face challenges in manufacturing sharp junction zones for varying optical powers, leading to discomfort and reduced refraction power due to significant thickness variations across the optic zone, which are difficult to fabricate and do not satisfy optical correction requirements for higher power lenses.

Innovation Solution

Incorporating diffractive structures in the peripheral regions of the optic zone to modify optical ray power, minimizing thickness variation and allowing for reduced edge thickness differences, thereby enabling the use of mixed refractive and diffractive designs to achieve desired optical powers without sharp junctions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If thickness variation is increased to achieve higher optical power correction, then refraction power is improved, but lens edge thickness becomes very thin or very thick leading to sharp junction zones that are difficult to manufacture and uncomfortable for patients

Engineering Contradiction:

Improverefraction powerVSAvoidmanufacturing difficulty of sharp junction zones

Core Design Contradiction:

PowerVSEase of manufacture

Solution Approach 1:

The lens is divided into two functional zones: a refractive optic zone for optical power correction and a diffractive junction zone for thickness transition. This segmentation allows the refractive zone to achieve high optical power while the diffractive zone handles the thickness variation, eliminating the need for sharp junctions and improving manufacturability.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different optical mechanisms are applied to different regions of the lens: refraction in the optic zone for power correction and diffraction in the junction zone for thickness transition. This local differentiation allows each zone to optimize its function, achieving high refraction power while maintaining manufacturable thickness profiles.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If thickness variation is minimized to reduce sharp junction areas and improve comfort, then ease of manufacture is improved, but refraction power is reduced and cannot satisfy optical correction requirements for higher power lenses

Engineering Contradiction:

Improveease of manufactureVSAvoidrefraction power

Core Design Contradiction:

Ease of manufactureVSPower

Solution Approach 1:

The lens combines refractive and diffractive optical mechanisms within a single structure. The refractive optic zone provides the necessary optical power while the integrated diffractive junction zone manages thickness transitions, allowing the lens to achieve both high refraction power and ease of manufacture simultaneously.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The diffractive junction zone acts as an intermediary between the refractive optic zone and the lens periphery. It mediates the thickness transition by using diffraction to gradually reduce thickness variation, allowing the refractive zone to maintain high power while avoiding sharp junctions.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Stability of the object's composition

If sharp junction zones are created to connect optic zone to periphery, then lens stability is improved, but manufacturing complexity increases and patient comfort is reduced

Engineering Contradiction:

Improvelens stabilityVSAvoidmanufacturing complexity

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The patent replaces the mechanical sharp junction structure with a diffractive optical structure. Instead of using a sharp physical transition zone, the diffractive patterns create an optical effect that achieves thickness transition, reducing manufacturing complexity while maintaining lens stability and improving comfort.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

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 solution allows for the production of lenses with uniform thickness profiles and enhanced optical performance across a range of powers, maintaining comfort and achieving 20/20 vision performance with reduced manufacturing complexity.

Implementation Method 1

Incorporating diffractive structures in the peripheral regions of the optic zone to modify optical ray power

Methodology Applied

Scientific EffectDiffraction: Diffraction

Implementation Method 2

Within optic zone, rays were refracted with different angles across the optic zone region and thus visual correction can be achieved

Methodology Applied

Scientific EffectRefraction: Refraction

Data Source

PatentUS11360325B2Employing diffractive structure to reduce soft contact lens variation

Publication Date: 2022.06.14 JOHNSON & JOHNSON VISION CARE INC

AI summary

An ophthalmic lens may comprise a main body comprising an optic zone and a peripheral zone disposed adjacent the optic zone, wherein the optic zone comprises a refractive structure that exhibits a first optical power and a diffractive structure disposed within the optic zone, wherein the diffractive structure exhibits a second optical power, wherein the ophthalmic lens is associated with a first target SKU optical power.