Progressive Addition Lens Design via Extra Astigmatism

Solution Overview

Problem

Progressive addition lenses suffer from aberrations and distortion due to the difference in powers between distance and near vision regions, leading to issues like blurring and narrowing of the clear vision area, which existing transmission-based design methods have not fully addressed.

Innovation Solution

A method for designing progressive addition lenses that involves determining a transmission astigmatic performance parameter by adding a predetermined amount of extra astigmatism in the near and intermediate vision regions, allowing for a power distribution that reduces inherent astigmatism and expands the clear vision area, while maintaining comfortable vision.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If transmission-based design is used to reduce aberrations, then optical quality improves, but the clear vision area becomes narrowed and distortion increases

Engineering Contradiction:

Improveoptical qualityVSAvoidclear vision area

Core Design Contradiction:

Measurement precisionVSArea of stationary object

Solution Approach 1:

The patent applies local quality by introducing extra astigmatism specifically in the near and intermediate vision regions while maintaining different power distribution characteristics in different areas of the lens. This localized adjustment optimizes optical quality in specific regions without compromising the overall clear vision area

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the astigmatic parameter by adding a predetermined amount of extra astigmatism to the transmission astigmatic performance parameter. This parameter modification allows the lens to achieve better optical quality while maintaining an adequate clear vision area through adjusted power distribution

Inventive Principle:

Principle #35Parameter changes

2Area of stationary object

If power distribution is adjusted to expand clear vision area, then visual field improves, but aberrations and distortion increase

Engineering Contradiction:

Improveclear vision areaVSAvoidaberrations

Core Design Contradiction:

Area of stationary objectVSObject-generated harmful factors

Solution Approach 1:

The patent applies local quality by introducing extra astigmatism specifically in the near and intermediate vision regions while maintaining different power distribution characteristics in different areas of the lens. This localized adjustment optimizes optical quality in specific regions without compromising the overall clear vision area

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent changes the astigmatic parameter by adding a predetermined amount of extra astigmatism to the transmission astigmatic performance parameter. This parameter modification allows the lens to achieve better optical quality while maintaining an adequate clear vision area through adjusted power distribution

Inventive Principle:

Principle #35Parameter changes

3Measurement precision

If extra astigmatism is added to reduce inherent astigmatism, then optical performance improves, but lens design complexity increases

Engineering Contradiction:

Improveoptical performanceVSAvoidlens design

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes the astigmatic parameter by adding a predetermined amount of extra astigmatism to the transmission astigmatic performance parameter. This parameter modification approach simplifies the overall design process while achieving improved optical performance

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent applies preliminary action by pre-determining the extra astigmatism amount and incorporating it into the transmission astigmatic performance parameter during the design phase. This preliminary determination simplifies subsequent manufacturing steps while achieving the desired optical performance

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11886047B2Spectacle lenses and methods for producing the same

Publication Date: 2024.01.30 HOYA LENS THAILAND LTD

AI summary

A lens, system for designing, computer program for designing and a method for designing, with a computer, a progressive addition lens including a distance vision region, a near vision region, and an intermediate vision region, wherein a power gradually changes between the distance vision region and the near vision region, and wherein the progressive addition lens is based on prescription data, the method including: determining a transmission astigmatic performance parameter corresponding to a sum of a prescribed astigmatism included in the prescription data and of a predetermined amount of extra astigmatism; determining lens surface data corresponding to the determined transmission performance parameter.