Diffractive Multifocal Intraocular Lens for Low-Glare Light Splitting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing multifocal intraocular lenses (IOLs) face challenges in efficiently distributing light to achieve optimal vision at multiple focal distances, leading to reduced light transmission and visual symptoms like glare and halos, particularly in varying light conditions.
Innovation Solution
The design of a multifocal IOL with asymmetrical diffractive surfaces featuring an odd number of diffractive orders, variable thickness, and concentric rings with specific diffractive patterns, optimized using the Gerchberg-Saxton iterative algorithm, ensures efficient light distribution and maintains diffractive profiles across steps, enhancing light transmission and vision clarity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If traditional multifocal IOL designs are used, then multiple focal distances can be provided, but light transmission efficiency decreases and visual disturbances increase
Solution Approach 1:
The patent employs asymmetrical diffractive surface topography with an odd number of diffractive orders (5 orders) to create an asymmetric energy flux distribution. This asymmetric design optimizes light transmission by directing more light to the desired focal points while reducing scattered light that causes glare and halos, thereby resolving the contradiction between maintaining multiple focal distances and minimizing visual disturbances
Solution Approach 2:
The patent utilizes variable thickness of the IOL lens body to optimize optical performance. By changing the thickness parameter radially and at different zones, the lens achieves efficient light distribution across multiple focal distances while maintaining high light transmission efficiency above 90%, thus reducing visual disturbances without sacrificing focal coverage
2Adaptability or versatility
If diffractive surfaces with multiple orders are used, then multiple focal distances are achieved, but manufacturing complexity increases
Solution Approach 1:
The diffractive surface is segmented into discrete, adjacent, concentric rings with specific diffractive profiles. Each ring corresponds to a specific diffractive order and creates a specific focal distance. This segmentation allows the complex multifocal function to be broken down into manageable zones that can be manufactured using standard techniques, reducing manufacturing complexity while maintaining multiple focal distances
Solution Approach 2:
The patent transitions from traditional two-dimensional diffractive patterns to a three-dimensional diffractive surface topography with variable height profiles. This dimensional change enables the integration of multiple diffractive orders (5 orders) within a compact structure, achieving versatile multifocal functionality without proportionally increasing manufacturing complexity
3Ease of operation
If light is divided into multiple focuses, then vision at different distances is improved, but light transmission to each focus decreases
Solution Approach 1:
The patent applies local quality by creating zone-specific diffractive profiles with different height and width characteristics. Each concentric ring zone is optimized for its specific focal distance, with the central zones having different diffractive profiles than the peripheral zones. This localized optimization ensures that light transmission efficiency is maximized for each focal distance while maintaining overall vision quality across multiple distances
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 IOL achieves light transmission efficiency above 90% and improved vision quality across varying light conditions, minimizing visual disturbances and maintaining clarity at different focal distances.
Implementation Method 1
The multifocal IOL includes at least one diffractive surface including a plurality of discrete, adjacent, diffractive, concentric rings
Implementation Method 2
Modern multifocal IOLs provide a more physiological division of light and, in this way, optimize the eyeglasses independence
Data Source
AI summary
A multifocal IOL including at least one diffractive surface including a plurality of discrete, adjacent, diffractive, concentric rings, having a radial phase profile cross-section with a near-symmetrical diffractive surface topography, and an odd number, greater than three, of diffractive orders and an asymmetrical distribution of energy flux over the diffractive orders.