Progressive Spectacle Lens Myopia Control Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional progressive spectacle lenses for myopia control often fail to effectively reduce accommodative lag during near vision tasks, leading to limited efficacy in preventing the progression of myopia, especially in children, due to adaptation and relaxation of the accommodative effort over time.
Innovation Solution
A progressive spectacle lens design featuring low mean power zones in the upper viewing zone and peripheral zones, with a narrow near vision zone surrounded by relatively low mean power, and steep power gradients, to stimulate additional accommodative effort and inhibit its relaxation, while minimizing accommodative lag.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional progressive spectacle lenses are used for myopia control, then distance and near vision correction is provided, but accommodative lag is not effectively reduced and myopia progression control is limited
Solution Approach 1:
The patent applies local quality by creating distinct zones with different optical properties: a near vision zone with higher additive power surrounded by peripheral zones with lower additive power. This local differentiation of power distribution maintains accommodative effort in the near vision zone while reducing accommodative lag through the peripheral zones, thereby improving myopia control efficacy without compromising accommodative response
Solution Approach 2:
The lens is segmented into multiple functional zones: a central near vision zone and surrounding peripheral zones with different additive powers. This segmentation allows the lens to provide different optical functions in different regions - the near vision zone for close work and the peripheral zones for maintaining accommodative lag reduction, resolving the contradiction between vision correction and accommodative response maintenance
2Ease of operation
If the near vision zone is made wider to provide comfortable near vision, then near vision comfort is improved, but accommodative lag increases and myopia control effectiveness decreases
Solution Approach 1:
The patent creates local quality differences by providing high additive power specifically in the near vision zone for comfort while surrounding it with peripheral zones of lower additive power to control accommodative lag. This localized power distribution allows the near vision zone to be sufficiently wide for comfort while the peripheral zones maintain accommodative effort, resolving the contradiction between near vision comfort and accommodative lag reduction
3Reliability
If the additive power in the near vision zone is increased to reduce accommodative lag, then accommodative effort is stimulated, but the lens complexity and difficulty of manufacturing increase
Solution Approach 1:
The patent segments the lens into zones with different additive powers, allowing the high additive power to be concentrated in the near vision zone for accommodating effort stimulation while the peripheral zones have lower power. This segmentation simplifies manufacturing compared to a uniform high-power lens, as the power distribution follows a systematic zonal pattern that can be manufactured using progressive lens techniques
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 design provides effective myopia control by maintaining the accommodative response similar to single vision lenses during near tasks, reducing accommodative lag, and potentially slowing myopia progression by making the near vision zone as narrow as practical with wide peripheral power depressions.
Implementation Method 1
an eye must be capable of focusing light on the retina
Implementation Method 2
a progressive spectacle lens design featuring low mean power zones in the upper viewing zone and peripheral zones, with a narrow near vision zone surrounded by relatively low mean power, and steep power gradients
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
A progressive spectacle lens is provided which includes: - an upper viewing zone (7) with a distance reference point (2A) providing a first refractive power, in particular a first mean refractive power, adapted to distance vision; - a lower viewing zone (5) with a near reference point (3A) providing a second refractive power, in particular the second mean refractive power, adapted to near vision, the second refractive power, in particular the second mean refractive power, representing an addition power relative to the first refractive power, in particular the first mean refractive power; - a corridor (6) between the upper viewing zone (7) and the lower viewing zone (5) in which the refractive power gradually changes from the first refractive power, in particular the first mean refractive power, to the second refractive power, in particular the second mean refractive power; and - a left peripheral zone (4L) and a right peripheral zone (4R) which are separated by the corridor and the lower viewing zone (5). Low mean power zones (10, 11, 12) are present in the upper viewing zone (7), the left peripheral zone (4L) and the right peripheral zone (4R) where the mean refractive power does not exceed the first refractive power, in particular the first mean refractive power, plus 0.125 D in said low mean power zones (10, 11, 12). In addition, the low mean power zones (10, 11, 12) may occupy at least 40 % of the area of the progressive spectacle lens.