Lens Thickness Reduction via Curvature Optimization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Traditional methods for modifying the thickness of ophthalmic lenses with free-form surfaces are inefficient, particularly for high-power lenses, as they require complex tools and increased processing time and cost, and do not effectively minimize center thickness or edge thickness, leading to wearer discomfort and aesthetic issues.

Innovation Solution

A computer-implemented method that modifies the back surface of an uncut lens blank by optimizing the curvature profile to reduce thickness, preserving the original curvature profile within a boundary line and transitioning to a predefined extreme curvature value radially outward, allowing for efficient processing with existing tools and maintaining optical properties.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If traditional methods are used to modify lens thickness for high-power lenses, then optical properties are maintained, but device complexity increases and processing time increases

Engineering Contradiction:
Improveoptical propertiesVSAvoidtool complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent applies parameter changes by systematically modifying the back surface curvature profile through mathematical optimization. The method varies curvature parameters radially outward from the optical zone to achieve thickness reduction while maintaining optical performance. This approach replaces complex physical tools with computational parameter optimization, directly resolving the contradiction between maintaining optical precision and reducing device complexity.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If traditional methods are used to modify lens thickness, then optical properties are maintained, but processing time increases

Engineering Contradiction:
Improveoptical propertiesVSAvoidprocessing time
Core Design Contradiction:
Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent implements preliminary action by pre-calculating the optimized back surface curvature profile using computer algorithms before manufacturing. The optimization process determines the complete thickness reduction strategy in advance, including the radial curvature distribution and transition zones. This pre-computation eliminates iterative adjustments during manufacturing, significantly reducing processing time while ensuring optical properties are maintained.

Inventive Principle:
Principle #10Preliminary action

3Ease of operation

If lens thickness is reduced to improve aesthetics and comfort, then wearer comfort improves, but manufacturing difficulty increases

Engineering Contradiction:
Improvewearer comfortVSAvoidmanufacturing difficulty
Core Design Contradiction:
Ease of operationVSEase of manufacture

Solution Approach 1:

The patent applies local quality by implementing different curvature characteristics in different radial zones of the lens. The optical zone maintains the original curvature profile to preserve optical performance, while the peripheral zones progressively transition to higher curvature values to reduce thickness. This localized differentiation allows thickness reduction for comfort and aesthetics without compromising the optical quality in the critical viewing area, and the systematic zonal approach simplifies manufacturing by providing clear regional specifications.

Inventive Principle:
Principle #3Local quality

4Shape

If extreme curvature values are applied to reduce edge thickness, then aesthetic appearance improves, but manufacturing precision requirements increase

Engineering Contradiction:
Improveedge thicknessVSAvoidcurvature control
Core Design Contradiction:
ShapeVSManufacturing precision

Solution Approach 1:

The patent implements dynamics by creating a continuous, progressive curvature transition from the optical zone to the peripheral zones. Rather than abrupt changes, the curvature profile dynamically adapts through intermediate zones with gradually increasing curvature values. This dynamic transition approach allows extreme curvature values at the edges for aesthetic thinness while maintaining manufacturability through controlled gradual changes, reducing the precision requirements compared to abrupt curvature changes.

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP2947505B1Method for reducing the thickness of a lens shape
Publication Date: 2018.10.31 CARL ZEISS VISION INC
  • EP2947505B1 patent drawingFigure 1
  • EP2947505B1 patent drawingFigure 2a
  • EP2947505B1 patent drawingFigure 2b

AI summary

The current invention is directed to a method (100), in particular a computer-implemented method, for providing a modified lens design (40) for an uncut lens blank (60), in particular through the use of a non-transitory computer readable medium. Further, a method (130), in particular a computer-implemented method, for reducing a thickness of an original lens design (10) of an uncut lens blank (60), in particular through the use of a non-transitory computer readable medium, is provided. Furthermore, a method (150) for manufacturing an uncut lens blank (60) and an uncut lens blank (60) are provided.