Zoom Lens Segmented Magnification Aberration Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing zoom lenses face challenges in achieving a wide view angle, high zoom ratio, and small size while maintaining high optical performance and suppressing image shake during zooming, as increasing the view angle leads to various aberrations that are difficult to correct.
Innovation Solution
A zoom lens design that includes a first lens unit with positive refractive power, a second lens unit with negative refractive power, an aperture stop, a third lens unit with positive refractive power, and a fourth lens unit with negative refractive power, where the first lens unit and aperture stop do not move during zooming, and the second, third, and fourth lens units move along different loci, satisfying specific conditional expressions to share magnification-changing functions effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of moving object
If the effective aperture of the first lens is increased to increase the view angle, then the view angle is improved, but the size of the lens barrel is increased
Solution Approach 1:
The zoom lens is divided into five lens units with alternating positive and negative refractive powers. The second and third lens units are configured to move along different loci during zooming, segmenting the magnification-changing function between them. This segmentation allows the first lens unit to maintain a smaller effective aperture while achieving a wide view angle through the coordinated movement of subsequent lens units.
2Area of moving object
If the refractive powers of lens units are increased to increase the view angle, then the view angle is improved, but various aberrations occur by large amounts
Solution Approach 1:
Each lens unit is assigned a specific refractive power sign (positive or negative) and specific movement characteristics. The second lens unit moves along one locus while the third lens unit moves along a different locus, creating localized functional differences that collectively correct aberrations across the entire optical system while maintaining a wide view angle.
Solution Approach 2:
The patent combines multiple lens units with alternating refractive power signs in a specific sequence. The positive and negative lens units work together to cancel out aberrations, while the combined movement of the second and third lens units along different loci provides both wide view angle and aberration correction simultaneously.
3Strength
If the first lens unit is fixed during zooming to increase strength, then the lens barrel strength is improved, but the drive unit power consumption increases
Solution Approach 1:
The magnification-changing function is segmented between the second and third lens units, which move along different loci. This segmentation allows the first lens unit to remain fixed, providing structural strength, while the distributed movement of subsequent lens units achieves the required zoom functionality with reduced power consumption.
4Strength
If the first lens unit is fixed during zooming to increase strength, then the lens barrel strength is improved, but image shake during zooming increases
Solution Approach 1:
The second and third lens units are given specific movement characteristics with different loci, creating localized functional differentiation. This allows the first lens unit to remain fixed for strength while the specialized movement paths of the second and third units compensate for image shake, resolving the contradiction between structural strength and image stability.
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 design achieves a wide view angle, high zoom ratio, and small size with improved optical performance by appropriately correcting aberrations and reducing the weight of the lens barrel, while maintaining a small F-number and suppressing image shake during zooming.
Implementation Method 1
a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power, and a fifth lens unit having a positive refractive power
Data Source
AI summary
A zoom lens includes, from an object side to an image side, a first lens unit having a positive refractive power, a second lens unit having a negative refractive power, an aperture stop, a third lens unit having a positive refractive power, a fourth lens unit having a negative refractive power, and a fifth lens unit having a positive refractive power. During zooming, the first lens unit and the aperture stop do not move and the second, third, and fourth lens units move along different loci. Lateral magnifications of the second lens unit at a wide angle end and at a telephoto end and lateral magnifications of the third lens unit at the wide angle end and at the telephoto end are each appropriately set based on predetermined mathematical conditions.