Prescription Lenslet Design for Spatial-Frequency Visual Stress Reduction

Solution Overview

Problem

Existing ophthalmic devices, particularly tinted lenses, fail to address visual stress effectively, affecting aesthetics, color perception, and circadian rhythm, and may induce fatigue and sleep issues.

Innovation Solution

A lens element with a prescription portion and lenslets providing distinct optical functions, designed to attenuate specific spatial frequencies, particularly around 3 cycles per degree, to reduce visual stress and improve comfort.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If tinted lenses are used to help people suffering from visual stress, then visual comfort may be improved, but aesthetics are compromised and color perception is significantly modified

Engineering Contradiction:

Improvevisual comfortVSAvoidcolor perception modification

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The lens is divided into multiple zones with different optical properties. The first zone has a first modulation transfer function while the second zone has a second modulation transfer function, allowing different regions to handle different visual tasks and frequency ranges independently

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the lens are assigned different optical characteristics. The first zone is optimized for certain spatial frequencies while the second zone addresses different frequencies, creating local optimization rather than uniform treatment across the entire lens

Inventive Principle:

Principle #3Local quality

2Ease of operation

If tinted lenses are worn all day long to reduce visual stress, then visual comfort is improved, but circadian rhythm control is affected and general fatigue is induced

Engineering Contradiction:

Improvevisual comfortVSAvoidcircadian rhythm disruption

Core Design Contradiction:

Ease of operationVSObject-generated harmful factors

Solution Approach 1:

The lens is divided into multiple zones with different optical properties. The first zone has a first modulation transfer function while the second zone has a second modulation transfer function, allowing different regions to handle different visual tasks and frequency ranges independently

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The lens uses specific modulation transfer functions that selectively attenuate certain spatial frequencies in a periodic pattern, allowing beneficial light frequencies to pass through while blocking harmful ones, thereby maintaining circadian rhythm while providing visual comfort

Inventive Principle:

Principle #19Periodic action

3Ease of operation

If a lens element attenuates specific spatial frequencies to reduce visual stress, then visual comfort is improved, but visual acuity may be degraded

Engineering Contradiction:

Improvevisual comfortVSAvoidvisual acuity

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The lens is divided into multiple zones with different optical properties. The first zone has a first modulation transfer function while the second zone has a second modulation transfer function, allowing different regions to handle different visual tasks and frequency ranges independently

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the lens are assigned different optical characteristics. The first zone is optimized for certain spatial frequencies while the second zone addresses different frequencies, creating local optimization rather than uniform treatment across the entire lens

Inventive Principle:

Principle #3Local quality

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 lens element effectively reduces visual stress by attenuating specific spatial frequencies, enhancing visual comfort and maintaining good visual acuity across various frequencies.

Implementation Method 1

each lenslet has a shape, a size and a position such that at least one portion of said lens element has a modulation transfer function whose values are configured so that the modulation transfer function of said lens element over a range of spatial frequencies comprised between 1 and 5 cycles per degree

Methodology Applied

Scientific EffectModulation transfer function attenuation: Filter (optical)

Data Source

PatentUS12399383B2Lens element and corresponding computer-implemented determining method

Publication Date: 2025.08.26 ESSILOR INTERNATIONAL(COMPAGNIE GENERALE D OPTIQUE)

AI summary

The invention relates to a lens element (1) intended to be worn by a wearer, comprising at least one prescription portion (2) having a first optical function configured to provide a dioptric correction of an eye of the wearer when the lens element (1) is worn by said wearer based on a prescription of the wearer, and a plurality of lenslets (3), each lenslet (3) of said plurality of lenslets being configured to provide at least one second optical function which differs from the first optical function,wherein each lenslet (3) has a shape, a size and a position such that at least one portion of said lens element (1) has a modulation transfer function (MTF) whose values are configured so that the modulation transfer function of said lens element 1 over a range of spatial frequencies comprised between 1 and 5 cycles per degree are lower or equal to 0.6.