Zoom Lens System Aberration Control via Parameter Changes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional zoom lens systems face challenges in achieving high optical performance and compactness while maintaining high precision in manufacturing due to sensitivity issues related to distance variation and decentering between lens groups, particularly affecting aberration correction and zoom ratio.
Innovation Solution
A zoom lens system with a four-lens-group configuration, where the distance between the first and second lens groups increases, and the distances between the second and third, and third and fourth lens groups decrease, while adhering to specific conditional expressions to minimize sensitivity and optimize focal lengths, using a combination of positive and negative refractive power lens groups with aspherical surfaces and aperture stops to achieve a high zoom ratio and improved optical performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If large aberrations are corrected by slightly changing the distance between the third lens group and the fourth lens group, then optical performance is improved, but distance variation sensitivity and decentering sensitivity increase significantly
Solution Approach 1:
The patent changes the zooming mechanism parameters by having the first lens group move a larger distance compared to conventional designs, while the third and fourth lens groups move smaller distances. This parameter redistribution reduces the sensitivity to distance variations and decentering between the third and fourth lens groups, thereby improving manufacturing reliability while maintaining optical performance.
2Adaptability or versatility
If zooming is carried out by varying distances before and after the second lens group having large refractive power, then zoom ratio is increased, but decentering sensitivity of the second lens group becomes high
Solution Approach 1:
The patent modifies the zooming parameters by adjusting the movement distances of each lens group. The first lens group moves a larger distance while the second lens group's movement is optimized to reduce decentering sensitivity, allowing high zoom ratio to be achieved without excessive sensitivity to manufacturing errors.
3Manufacturing precision
If high precision is required upon manufacturing the zoom lens system, then optical performance is improved, but manufacturing difficulty and cost increase
Solution Approach 1:
The patent optimizes the zooming parameters and lens group configuration to reduce sensitivity to manufacturing tolerances. By having the first lens group move a larger distance and the third and fourth lens groups move smaller distances, the system achieves good optical performance with relaxed manufacturing precision requirements, thereby easing manufacturing difficulty and reducing cost.
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 system achieves a high zoom ratio of 5.0 or more with reduced decentering sensitivity, excellent aberration correction, and ease of manufacturing, ensuring high optical performance across the focal length range.
Implementation Method 1
a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power
Data Source
AI summary
Providing a zoom lens system that has a high zoom ratio, high optical performance, and compactness, and is easy to be manufactured. The zoom lens system includes, in order from an object, a first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having positive refractive power, and a fourth lens group having positive refractive power. Zooming from a wide-angle end state to a telephoto end state is carried out by moving each lens group along the optical axis such that a distance between the first lens group and the second lens group increases, a distance between the second lens group and the third lens group decreases, a distance between the third lens group and the fourth lens group decreases. A zoom ratio is 5.0 or more. Given conditional expressions are satisfied.