Five-Lens Imaging System Aberration Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional imaging lenses for in-vehicle and monitor cameras face challenges in achieving a wide angle of view with high optical performance while being cost-effective and weather-tolerant, especially with the increasing resolution of imaging devices.
Innovation Solution
A five-lens imaging lens system comprising a negative first lens, a negative second lens with a concave surface facing the image side, a positive third lens, an aperture stop, a positive fourth lens, and a fifth lens with a concave surface facing the object side, where at least one of the second, fourth, and fifth lenses has an aspheric surface, and specific Abbe numbers and curvature radii are used to correct chromatic and field aberrations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional five-lens imaging lenses are used with large Abbe number materials, then manufacturing is easier and cost is lower, but longitudinal chromatic aberration cannot be corrected excellently
Solution Approach 1:
The patent applies parameter changes by selecting specific Abbe number ranges for lens materials: the third lens uses material with Abbe number 20-40 and the fifth lens uses material with Abbe number 25-35. These parameter specifications enable excellent longitudinal chromatic aberration correction while maintaining manufacturability through well-established material options within these ranges.
2Manufacturing precision
If cemented lenses are used to improve optical performance, then aberration correction is enhanced, but the lens becomes inappropriate for tough conditions and cost increases
Solution Approach 1:
The patent applies segmentation by designing all five lenses as separate, uncemented elements. Each lens can be independently manufactured and assembled, avoiding the reliability issues of cemented joints in harsh environments while maintaining the ability to correct aberrations through precise optical design and material selection for each individual lens.
3Manufacturing precision
If many glass lenses are used to achieve high performance, then optical quality improves, but manufacturing cost increases
Solution Approach 1:
The patent applies parameter changes by specifying Abbe number ranges that balance optical performance and cost: third lens (Abbe number 20-40) and fifth lens (Abbe number 25-35). These parameter specifications enable the use of cost-effective materials that achieve high optical performance without requiring expensive specialized glass types.
4Manufacturing precision
If all spherical lenses are used to simplify manufacturing, then production is easier, but performance is insufficient for high-resolution imaging devices
Solution Approach 1:
The patent applies spheroidality by incorporating aspheric surfaces on the object-side surface of the second lens and/or the image-side surface of the third lens. These aspheric designs enable correction of spherical aberration and field curvature, achieving high performance for high-resolution imaging devices while maintaining relatively simple manufacturing processes.
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 system achieves a wide angle of view, high optical performance, and cost-effectiveness, capable of handling high-resolution imaging devices, with improved correction of chromatic and field aberrations.
Implementation Method 1
at least one of the second lens, the fourth lens and the fifth lens has at least an aspheric surface
Implementation Method 2
the Abbe number of the material of the third lens and the Abbe number of the material of the fifth lens for d-line are less than or equal to 30, and the Abbe number of the material of the fourth lens for d-line is greater than or equal to 40
Data Source
AI summary
An imaging lens includes negative first lens, negative second lens having a concave surface facing the image side, positive third lens, aperture stop, positive fourth lens, and fifth lens having a concave surface facing the object side, which are arranged sequentially from the object side. At least one of second lens, fourth lens and fifth lens has at least an aspheric surface. The Abbe number of third lens and the Abbe number of fifth lens are less than or equal to 30, and the Abbe number of fourth lens is greater than or equal to 40. Further, the following formula (1) is satisfied:1.0<(R3−R4)/(R3+R4) (1),whereR3: the paraxial curvature radius of an object-side surface of second lens, andR4: the paraxial curvature radius of an image-side surface of second lens.