Extended-Depth IOL Surface Profile for Intermediate Vision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional intraocular lenses (IOLs) primarily focused on distance vision lack the ability to extend depth of focus for intermediate vision, necessitating additional eyewear for near and intermediate vision correction, and age-related decline in depth of focus diminishes visual acuity.
Innovation Solution
An ophthalmic lens with a multi-layered surface profile comprising a phase shift structure, zonal structure, and base structure, featuring a trapezoid phase shift and inner power zone to enhance depth of focus and visual acuity for intermediate vision while maintaining distance vision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional intraocular lenses are designed for distance vision, then distance vision performance is improved, but intermediate vision depth of focus deteriorates
Solution Approach 1:
The lens surface is segmented into distinct functional zones: a central distance vision zone, an intermediate vision zone with modified curvature, and a peripheral zone. This segmentation allows each region to contribute to different focal points, enabling the lens to provide both distance and intermediate vision without compromising either function.
Solution Approach 2:
The lens applies local quality changes by modifying the surface curvature specifically in the intermediate vision zone while maintaining the optimal curvature for distance vision in the central zone. This localized modification enables the lens to extend depth of focus for intermediate objects without degrading distance vision performance.
2Measurement precision
If additional eyewear is prescribed for near and intermediate vision correction, then intermediate vision is improved, but device complexity increases
Solution Approach 1:
The intraocular lens is designed to perform multiple functions: it provides distance vision correction, extends depth of focus for intermediate vision, and maintains overall optical quality. This multi-functionality eliminates the need for additional corrective eyewear, as the single lens addresses multiple vision needs that would otherwise require separate devices.
3Measurement precision
If age-related decline in depth of focus occurs, then visual acuity deteriorates, but this is a natural physiological process
Solution Approach 1:
The lens design proactively compensates for age-related depth of focus decline by incorporating an extended depth of focus mechanism that is built into the lens structure itself. This preliminary design feature counteracts the natural physiological deterioration that occurs with aging, maintaining visual acuity across a broader range of distances without requiring future interventions.
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 design extends depth of focus up to 2.38 D, improving visual acuity by 0.2 for pupil diameters of 2 mm to 6 mm, and maintains clear distance vision without additional visual disturbances.
Implementation Method 1
the transition region is adapted such that a phase of radiation incident thereon varies linearly over at least a portion of the radial extent between the first boundary and the second boundary so as to generate a phase shift between the first and second boundaries
Implementation Method 2
The zonal structure includes an inner power zone having a first curvature and an outer transition zone having a second curvature
Data Source
AI summary
The present disclosure provides an ophthalmic lens (such as an IOL) that is designed to enhance depth of focus for intermediate vision performance, while maintaining distance vision. The lens may include an optic having an anterior surface and a posterior surface disposed about an optical axis. One of the surfaces (e.g., the anterior surface) may have a surface profile involving a superposition of at least three structures or profiles, including a base structure, a phase shift structure having an inner region, an outer region and a transition region, and a zonal structure having an inner power zone and an outer transition zone.