Corneal Topography Illumination Using Lens Array
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing illumination systems for measuring corneal topography face challenges such as distance-dependent measurement accuracy, complex installation due to reflective surfaces, and limited free diameters, which complicate modular use and increase costs.
Innovation Solution
A compact illumination system using a plurality of illumination modules with a lens array producing a spatially distributed, collimated illumination pattern, employing diverging lenses with negative focal length to ensure distance-independent measurements and reduce manufacturing errors, while keeping the region around the optical axis free for other components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If reflective surfaces are used for collimation, then large deflection angles can be realized, but surface defects have a stronger effect on collimation and manufacturing complexity increases
Solution Approach 1:
The patent replaces reflective surfaces with refractive optical elements (lenses). Instead of using mirrors or reflective interfaces to achieve beam deflection and collimation, the invention employs lenses with specific focal lengths to refract and collimate the light beams. This substitution eliminates the sensitivity to surface defects inherent in reflective systems while maintaining the capability to achieve necessary deflection angles through optical design.
Solution Approach 2:
The invention changes the optical parameters by using lenses with negative focal lengths arranged in arrays. By varying the focal length parameters and the spatial arrangement of lens elements, the system achieves the required beam deflection and collimation without relying on reflective surfaces. This parameter-based approach allows precise control over beam characteristics while simplifying manufacturing requirements.
2Use of energy by moving object
If beams extend in divergent fashion between light source and collimation unit, then illumination can be achieved, but smaller free diameters are available for other components
Solution Approach 1:
The patent applies preliminary collimation by positioning the lens array at a specific distance from the light source where the beams have not yet diverged significantly. The lenses pre-collimate the beams before they fully diverge, allowing the optical axes to remain clear and free for other system components while still achieving comprehensive illumination coverage of the cornea.
Solution Approach 2:
The invention transitions from a single-point light source to a distributed array of lens elements. This dimensional change from point to array allows each lens to handle a portion of the illumination task, collectively achieving full coverage while maintaining a compact, space-efficient configuration that preserves free diameter along the optical axis.
3Measurement precision
If telecentric detection is used for distance-independent measurement, then measurement accuracy is improved, but system complexity and installation space requirements increase
Solution Approach 1:
The patent divides the illumination function into multiple independent lens modules arranged in an array. Each lens element acts as an independent illumination channel, collectively providing telecentric illumination without requiring a complex monolithic optical system. This segmentation simplifies the overall system architecture while achieving distance-independent measurement capability.
Solution Approach 2:
The lens array serves multiple functions simultaneously: it collimates the illumination beams, defines the angular distribution of light, and enables telecentric measurement geometry. This multi-functionality reduces the need for separate optical components, thereby simplifying the overall system while maintaining measurement precision and distance independence.
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
Enables accurate, distance-independent corneal topography measurements with reduced manufacturing complexity and costs, allowing for easier integration with other systems and improved uniform illumination.
Implementation Method 1
the unit for producing an illumination pattern produces a spatially distributed, collimated illumination pattern
Data Source
AI summary
An illumination system for producing an illumination pattern for measuring the cornea of an eye and, in particular, for determining the topography thereof and in so doing facilitating distance-independent measurements. The illumination system according to the invention for determining the topography of the cornea of an eye includes an illumination unit and a unit for producing an illumination pattern, wherein the illumination unit includes a plurality of illumination modules. A lens array which produces a spatially distributed, collimated illumination pattern is used as a unit for producing an illumination pattern. The illumination system produces an illumination pattern, by which the topography of the cornea of an eye can be determined. Here, the illumination system is designed as a compact module, and so it can be easily combined with other measurement systems, without colliding with the beam paths thereof.