Floating Macro Lens Layout for High Magnification and Short Lens Length
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing macro lenses face challenges in achieving high optical performance while maintaining a compact size and enabling image capturing at increased imaging magnifications, particularly in transitioning from infinite-distance to close-distance object focusing, due to difficulties in correcting aberrations and shortening the total lens length.
Innovation Solution
The optical system employs a floating system with multiple focus lens units, including a partial optical system with negative refractive power on the image side, allowing for a compact design that maintains high optical performance by adjusting the interval between lens units and satisfying specific conditional expressions to balance aberration correction and lens length.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If a lens unit with positive refractive power is positioned at the closest position to the image plane to shorten the moving distance of the focus lens unit, then the moving distance is reduced and optical performance is maintained, but the lens diameter increases as imaging magnification increases
Solution Approach 1:
The patent changes the refractive power parameter of the partial optical system on the image side from positive to negative. This parameter change allows the lens unit to achieve both short moving distance and reduced lens diameter by utilizing the negative refractive power to counteract the beam expansion that would otherwise require larger lens elements
Solution Approach 2:
The patent applies local quality by creating a specific configuration where only the partial optical system on the image side has negative refractive power, while other parts of the lens system maintain their traditional positive refractive power. This localized application of negative refractive power solves the contradiction without requiring the entire lens system to be redesigned
2Adaptability or versatility
If the optical system is designed to achieve high imaging magnification (β=−1.2), then close-up image capturing capability is improved, but aberration correction becomes more difficult and total lens length increases
Solution Approach 1:
The patent achieves high imaging magnification (β=−1.2) while controlling lens length by changing the refractive power parameter of the partial optical system to negative. This parameter change enables the system to achieve the required magnification without proportionally increasing the total lens length, as the negative refractive power helps fold the optical path more efficiently
Solution Approach 2:
The patent employs a floating focus system where the intervals between adjacent lens units dynamically change during focusing from infinite-distance to close-distance objects. This dynamic adjustment allows the system to maintain optimal aberration correction and compact length across different magnification states, rather than being fixed at a single configuration
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 high optical performance and compactness by effectively correcting aberrations and shortening the total lens length, enabling image capturing at the same or higher magnifications without increasing the lens diameter.
Implementation Method 1
an optical system in which an interval between adjacent lens units is configured to change during focusing from an infinite-distance object to a close-distance object, and in which in a first in-focus position β=−1.2 is satisfied, where β is a lateral magnification of the optical system
Data Source
AI summary
In an optical system according to each exemplary embodiment, an interval between adjacent lens units changes in focusing from an infinite-distance object to a close-distance object, and a first in-focus state in which β=−1.2 is obtained can be caused, where β is a lateral magnification of an entire system. The optical system according to each exemplary embodiment includes a plurality of focus lens units, and out of a focus lens unit having a largest absolute value of a focus sensitivity and a focus lens unit having a second largest absolute value of a focus sensitivity in a state in which focus is put on an infinite-distance object, a focus lens unit disposed on an object side is a lens unit LA, and a focus lens unit disposed on an image side is a lens unit LB. A partial optical system LC including all lenses disposed on the image side of the lens unit LB has negative refractive power. The partial optical system LC satisfies a predetermined conditional expression.