Zoom Lens With Object-Facing Meniscus for Wide-Angle Imaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a demand for a zoom lens that offers a large image circle, wide angle of view, and small size with favorable optical performance, which existing technologies have not adequately addressed.
Innovation Solution
A zoom lens design comprising a first lens group with a positive refractive power, a middle group with multiple lens groups, and a final lens group, where spacings between adjacent lens groups change during magnification, including two negative lenses with specific refractive power configurations and focal length relationships, and incorporating a meniscus lens with a convex surface facing the object side.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a zoom lens is designed with a large image circle and wide angle of view, then the coverage and field of view are improved, but the lens size and complexity increase
Solution Approach 1:
The zoom lens is divided into multiple lens groups (first lens group with positive refractive power, second lens group with negative refractive power, and subsequent lens groups) that can move independently relative to each other. This segmentation allows each group to contribute differently to the overall optical performance, enabling a large image circle and wide angle of view while controlling the total lens size through coordinated movement of compact groups.
Solution Approach 2:
The patent employs a zoom mechanism where lens groups move along the optical axis in different directions and at different rates. By utilizing this dimensional movement, the lens system can achieve variable focal lengths and maintain a large image circle without proportionally increasing the physical volume of the lens housing.
2Reliability
If a zoom lens includes multiple lens groups with varying spacings to achieve wide angle and large image circle, then optical performance is improved, but the number of components and device complexity increase
Solution Approach 1:
Each lens group in the zoom lens is designed to serve multiple functions. For example, the first lens group with positive refractive power and the second lens group with negative refractive power work together not only to establish the wide angle of view but also to correct various optical aberrations simultaneously. This multi-functionality reduces the need for additional dedicated correction elements, thereby controlling device complexity.
Solution Approach 2:
The patent utilizes conditional expressions that define specific ranges for focal lengths, refractive powers, and spacing relationships between lens groups. By optimizing these parameters within defined ranges, the lens system achieves favorable optical performance with a manageable number of components, avoiding unnecessary complexity while maintaining reliability.
3Area of stationary object
If the first lens group has a positive refractive power with specific focal length relationships, then the wide angle of view is achieved, but the refractive power distribution and aberration control become more challenging
Solution Approach 1:
The patent assigns specific refractive power characteristics to different lens groups based on their local functions. The first lens group has a positive refractive power optimized for establishing the wide angle of view, while the second lens group has a negative refractive power specifically for correcting aberrations introduced by the first group. This localized optimization of refractive power distribution simplifies the overall aberration control strategy.
Solution Approach 2:
The zoom lens employs an asymmetric arrangement of lens groups with different refractive power signs and magnitudes. The conditional expressions define asymmetric relationships between the focal lengths and spacing of adjacent groups, which enables effective aberration correction while maintaining a compact wide-angle design. This asymmetric configuration is more efficient than symmetric arrangements for achieving wide angles with controlled aberrations.
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 a zoom lens with a large image circle, wide angle of view, and small size, while maintaining favorable optical performance by suppressing various aberrations and reducing weight through strategic lens group arrangements and refractive power management.
Implementation Method 1
a first lens group G1 having a positive refractive power that is disposed closest to an object side
Implementation Method 2
the first lens group G1 includes two negative lenses consecutively arranged in order from a position closest to the object side to the image side
Implementation Method 3
a negative lens closer to the object side is a meniscus lens that has a convex surface facing the object side
Implementation Method 4
a middle group GM that includes a plurality of lens groups; and a final lens group GE that is disposed closest to an image side
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A zoom lens includes: a first lens group having a positive refractive power that is disposed closest to an object side; a middle group that includes a plurality of lens groups; and a final lens group that is disposed closest to an image side. All of spacings between adjacent lens groups change during changing magnification. The first lens group includes two negative lenses consecutively arranged in order from a position closest to the object side to the image side, and among the two negative lenses, a negative lens closer to the object side is a meniscus lens that has a convex surface facing the object side. The zoom lens satisfies Conditional Expression of 0.1 < fw/f1 < 0.8 regarding a focal length f1 of the first lens group and a focal length fw of the zoom lens at a wide angle end.