Aspheric Lenslet Array for Laparoscope Illumination Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional laparoscope illumination systems suffer from a narrow field-of-view and non-uniform irradiance distribution, limiting the ability to clearly observe bodily organs, especially at the center and edges of the illuminated field, due to the numerical aperture of the lightguide and poor optical performance.
Innovation Solution
An optically-transparent component with a tubular element and aspheric lenslets is integrated into the illumination system, redistributing light energy across the field-of-view through a judiciously designed output end facet, enhancing uniformity and increasing the field-of-view by using an array of aspheric lenslets that encircle the optical axis.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a conventional lightguide illumination system is used, then the structure is simple, but the field-of-view is narrow and irradiance distribution is non-uniform
Solution Approach 1:
The illumination system is segmented into multiple aspheric lenslets arranged in an annular array, where each lenslet independently shapes and redirects light. This segmentation enables wider field-of-view coverage while maintaining manageable structural complexity through modular lenslet design
Solution Approach 2:
The patent transitions from a single-axis lightguide structure to a two-dimensional annular array of lenslets encircling the optical axis. This dimensional expansion allows light to be distributed across a wider angular range, significantly increasing the field-of-view without proportionally increasing overall system complexity
2Illumination intensity
If a conventional lightguide illumination system is used, then the structure is simple, but the irradiance distribution is non-uniform with most energy concentrated at the center
Solution Approach 1:
Different regions of the illumination system are assigned different functions: the aspheric lenslets in the annular array are specifically designed to redirect light from the high-intensity center region toward the low-intensity edge regions. This local functional differentiation achieves uniform irradiance distribution across the field-of-view
Solution Approach 2:
The aspheric lenslets serve as intermediary optical elements between the lightguide output and the illuminated target. These lenslets mediate the non-uniform light distribution by refracting and redirecting rays, transforming the concentrated central energy into a uniform distribution across the entire field-of-view
3Area of stationary object
If the numerical aperture of the lightguide is increased to widen the field-of-view, then the field-of-view increases, but the irradiance uniformity deteriorates
Solution Approach 1:
The illumination system dynamically adapts light distribution across different field angles through the aspheric lenslet array. Each lenslet is designed with specific optical power to redirect light at appropriate angles, maintaining uniform irradiance across the expanded field-of-view that would otherwise exhibit non-uniform distribution
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 solution significantly improves the uniformity of irradiance across the entire field-of-view, allowing for clearer observation of bodily organs, even at large field angles, and enhances the optical performance of laparoscopes by providing a wider field of view and more uniform illumination.
Implementation Method 1
an annular array of aspheric lenslets that encircle an optical axis of the lightguide and that each have a negative optical power
Data Source
AI summary
An optical element, wherein axially symmetric or not, an output surface of which contains a plurality of indentations configured to increase a degree of divergence of light that is incident onto such surface through an input surface of the optical element. In one implementation, each of the indentations defines a corresponding aspheric lenslet the plurality of which encircles the central opening in the optical element. The optical element can be configured as a lightguide having the specified output surface. An illumination system for a laparoscope employing such optical element as an addition to the optical fiber bundle of the laparoscope or as a fiber bundle itself that has the specified output surface.