Low Thermal-Drift Optical Lens Design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current imaging lenses face challenges in achieving low thermal drift, high resolution, wide viewing angles, and miniaturized layouts while maintaining low fabrication costs and 24-hours confocal image-capturing capability.
Innovation Solution
A low thermal-drift optical lens design comprising a first lens group and a second lens group with at least one aspheric plastic lens, arranged from magnified to minified sides, and an aperture stop, optimizing refractive powers and lens configurations to minimize thermal drift and overall lens length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the number of lenses is increased to achieve high optical performance, then imaging quality is improved, but device complexity and fabrication costs increase
Solution Approach 1:
The optical lens is divided into two lens groups (first lens group with negative refractive power and second lens group with positive refractive power), each containing specific numbers of lenses (1-3 lenses per group). This segmentation allows achieving high imaging quality with a reduced total number of lenses (5-7 lenses), simplifying the overall device complexity while maintaining optical performance.
Solution Approach 2:
The patent employs aspheric plastic lenses with specific refractive indices and Abbe numbers, and optimizes parameters such as focal lengths, spacing between lenses, and surface curvatures. These parameter optimizations enable high imaging quality to be achieved with fewer lenses, reducing both device complexity and fabrication costs.
2Adaptability or versatility
If the lens configuration is optimized for wide viewing angles, then field of view is improved, but thermal drift increases
Solution Approach 1:
Different lens groups are assigned specific functions: the first lens group (with negative refractive power) is optimized for wide viewing angles and field of view, while the second lens group (with positive refractive power) is optimized to minimize thermal drift. This local quality differentiation allows the system to achieve both wide viewing angles and low thermal drift simultaneously.
Solution Approach 2:
The patent uses aspheric plastic lenses with specific refractive indices (1.5-1.7) and Abbe numbers (20-60), combining materials with different thermal properties. The cemented lens structure joins lenses with different materials to achieve both wide viewing angles and thermal stability, reducing thermal drift while maintaining optical performance.
3Length of moving object
If the overall lens length is reduced for miniaturization, then device size is improved, but optical performance deteriorates
Solution Approach 1:
The patent achieves a compact overall lens length (less than 11 mm) by optimizing the spacing and arrangement of lenses within two groups. The lenses are nested compactly along the optical axis with minimized air gaps, allowing high optical performance to be achieved in a miniaturized configuration.
Solution Approach 2:
Aspheric lens surfaces are employed to correct optical aberrations in the miniaturized configuration. The aspheric profiles allow for compact lens spacing while maintaining focus quality and reducing distortion, enabling high optical performance in a shortened overall lens length.
4Ease of manufacture
If aspheric plastic lenses are used to reduce fabrication costs, then manufacturing cost is improved, but manufacturing precision becomes more difficult to control
Solution Approach 1:
The aspheric surfaces are defined with specific mathematical parameters and coefficients that can be precisely controlled during injection molding. By optimizing these parameters within certain ranges, the patent achieves both cost-effective manufacturing and high surface accuracy, resolving the contradiction between fabrication cost and manufacturing precision.
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 achieves lower thermal drift, wider viewing angles, high resolution, and better imaging quality with reduced fabrication costs and a miniaturized layout, supporting 24-hours confocal image-capturing capability within a compact form.
Implementation Method 1
The first lens group includes a first lens and a second lens, the second lens group includes a third lens and a cemented lens, and at least one of the second lens and the third lens is an aspheric plastic lens
Implementation Method 2
the second lens group includes a third lens and a cemented lens
Data Source
AI summary
A low thermal-drift optical lens includes a first lens group, a second lens group and an aperture stop. The first lens group includes a first lens and a second lens, and the second lens group includes a third lens and a cemented lens. The aperture stop is disposed between the second lens and the cemented lens, and a lens with a refractive power of the low thermal-drift optical lens closest to the minified side has at least one inflection point. In an operating temperature range of −40° C. to 80° C., a thermal drift of the low thermal-drift optical lens relative to a focal plane at 25° C. is less than or equal to 10 um.