Compact Zoom Optic System with Negative Refractive Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wide-angle zoom lens systems for cameras with solid-state image pickup devices face challenges in achieving a balance between compactness, high magnification, and a wide viewing angle while maintaining cost-effectiveness, as previous designs either compromise on magnification, viewing angle, or increase the complexity and size of the lens barrel.
Innovation Solution
A compact zoom optic system is designed with a first lens group having negative refractive power, a second lens group with positive refractive power, and a third lens group also with positive refractive power, where the first lens group consists of two lenses, and the system satisfies specific conditions for focal length and viewing angle to achieve high magnification and a wide viewing angle, using materials with refractive indices and Abbe values that optimize lens construction and minimize the number of lens elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the first lens group is constructed with three lenses to achieve a wide viewing angle of 80° or more, then the viewing angle is improved, but the lens barrel size increases and compactness deteriorates
Solution Approach 1:
The patent extracts the essential function of the first lens group (negative refractive power for wide-angle) and implements it with only two lenses instead of three, removing the extra lens while maintaining the wide viewing angle of 80° or more, thus reducing lens barrel size
Solution Approach 2:
The patent changes the refractive power parameter of the first lens group by using two lenses with specifically selected refractive indices and Abbe values, achieving the required negative refractive power for wide-angle without needing a third lens
2Adaptability or versatility
If five lens groups are used to achieve high magnification of 7 and wide viewing angle of 75° or more, then magnification and viewing angle are improved, but device complexity and lens barrel size increase
Solution Approach 1:
The patent extracts and eliminates two lens groups from the conventional five-group design, achieving high magnification (3-4) and wide viewing angle (80° or more) with only three lens groups, thereby reducing device complexity
Solution Approach 2:
The first lens group with negative refractive power performs multiple functions: it enables wide-angle viewing, contributes to zoom functionality, and replaces the need for separate shift lens groups found in other designs
3Adaptability or versatility
If six lens groups are used to achieve zoom functionality, then magnification is improved, but manufacturing cost increases
Solution Approach 1:
The patent removes three lens groups from the conventional six-group design, achieving zoom functionality with only three lens groups, which directly reduces manufacturing cost while maintaining high magnification capability
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 solution provides a compact, cost-effective zoom optic system with high magnification and a wide viewing angle, suitable for digital cameras and camcorders, by optimizing lens configuration and material properties to reduce size and complexity while maintaining high optical performance.
Implementation Method 1
a first lens group having a negative refractive power
Implementation Method 2
a second lens group having a positive refractive power; and a third lens group having a positive refractive power
Data Source
AI summary
A wide-angle zoom optic system includes: in an order from an object, a first lens group having a negative refractive power; a second lens group having a positive refractive power; and a third lens group having a positive refractive power, wherein the first lens group includes two lens elements. In the zoom optic system, the ratio of the distance between the last lens element with respect to the object and an image field at a wide-angle position to a focal length at the wide-angle position is adjusted, so that a compact zoom optic system having a high magnification and a wide viewing angle can be implemented.