Five-Lens Imaging Lens Compact Design for In-Vehicle Cameras
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing imaging lenses for in-vehicle cameras face challenges in achieving a small, fast, and inexpensive design while maintaining high optical performance and weather resistance across a wide temperature range.
Innovation Solution
The design incorporates a five-lens optical system with specific lens configurations and conditional expressions to optimize the arrangement of lenses, including a first negative lens with a concave surface, a second positive lens, a biconcave third lens, a positive fourth lens, and a biconvex fifth lens, without using expensive aspheric lenses, to achieve a compact and cost-effective imaging lens.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a five-lens optical system with spherical lenses is used, then manufacturing cost is reduced and ease of manufacture is improved, but optical performance deteriorates
Solution Approach 1:
The patent applies parameter changes by carefully controlling specific geometric parameters of the spherical lenses, including curvature radii (R1-R7), thicknesses (D1-D3), and air spaces (D2, D4, D5), along with refractive indices (N1-N5) and Abbe numbers (ν1-ν5). By optimizing these parameters within specific ranges, the patent achieves sufficient optical performance correction using simple spherical lenses, eliminating the need for complex aspheric surfaces while maintaining manufacturing simplicity.
2Volume of moving object
If the lens system is made compact, then size is reduced, but optical performance deteriorates
Solution Approach 1:
The patent segments the optical system into five distinct lens units with alternating positive and negative powers, arranged in a specific sequence (negative, positive, negative, positive, positive). This segmentation allows each lens to contribute specifically to correcting different types of optical aberrations, enabling compact design while maintaining optical performance through distributed functional responsibility across multiple elements.
Solution Approach 2:
The patent utilizes the air space dimension between lenses (specifically D4, the distance from the second lens to the stop, and D5, the distance from the stop to the third lens) as a critical parameter for aberration correction. By optimizing these inter-lens distances rather than relying solely on lens curvature, the patent achieves effective optical performance in a compact form factor.
3Manufacturing precision
If aspheric lenses are used, then optical performance is improved, but manufacturing cost increases
Solution Approach 1:
The patent employs standard spherical lenses that can be manufactured using conventional, cost-effective molding or grinding techniques. By avoiding aspheric surfaces that require complex and expensive manufacturing processes, the patent achieves a cost-effective solution that maintains sufficient optical performance for the intended application, effectively replacing expensive specialized components with simpler, cheaper alternatives.
4Illumination intensity
If the F number is reduced for night use, then brightness is improved, but lens size increases
Solution Approach 1:
The patent designs a multi-functional five-lens optical system that simultaneously achieves multiple objectives: correcting various optical aberrations (spherical, coma, astigmatism, field curvature), enabling compact size, and achieving fast F number for night vision capability. The alternating positive-negative lens configuration allows the system to fulfill multiple optical requirements without requiring separate specialized components, thereby achieving brightness improvement without proportional size increase.
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
This configuration results in a small, fast, and inexpensive imaging lens with improved optical performance, capable of withstanding various environmental conditions and reducing manufacturing costs, while maintaining high image quality and resistance to temperature variations.
Implementation Method 1
The first lens has a negative power and includes a concave surface facing an image side. The second lens has a positive power. The third negative lens is a biconcave lens. The fourth lens has a positive power. The fifth lens has a positive power and includes a convex surface facing an image side.
Data Source
AI summary
An imaging lens includes, in order from an object side, a first lens having a negative power and including a concave image-side surface, a second lens having a positive power, a stop, a third negative lens, which is a biconcave lens, a fourth lens having a positive power, and a fifth lens having a positive power and including a convex image-side surface. The imaging lens satisfies the following conditional expressions:0.18<(D4+D5)/f<0.44, and0.18<D1/f where f denotes a focal length of an entire lens system, D1 denotes a thickness of a center of the first lens, D4 denotes a distance from an image-side surface of the second lens to the stop on an optical axis, and D5 denotes a distance from the stop to an object-side surface of the third lens on the optical axis.