Wide-angle lens freeform surface design
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Designing wide-angle optical systems with asymmetrical 2D object-image mapping functions is computationally demanding, as existing methods struggle to find the optimal freeform surface shape to achieve the desired distortion profile, especially with wide-angle lenses that exhibit significant optical distortion.
Innovation Solution
An iterative method that adjusts the sag, curvature, or slope of a freeform surface on a predefined sampling grid to achieve the desired 2D object-image mapping function, while optimizing other optical surfaces to meet optical specifications, using software tools like Zemax, Matlab, or custom programming to interpolate and fit the surface shape.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If rotationally symmetrical aspherical surfaces are used, then the optical design is simpler and manufacturing is easier, but the ability to create asymmetrical distortion profiles is limited
Solution Approach 1:
The patent introduces freeform surfaces with asymmetrical profiles to break the rotational symmetry constraint. These freeform surfaces enable the creation of custom asymmetrical distortion profiles while maintaining control over optical aberrations, directly addressing the limitation of rotationally symmetrical surfaces
2Manufacturing precision
If iterative optimization methods are used to find optimal freeform surface shapes, then the desired distortion profile can be achieved, but the computational complexity and time required increase significantly
Solution Approach 1:
The patent employs a systematic iterative optimization methodology that preliminarily establishes the freeform surface design framework before detailed optimization. This structured approach guides the optimization process efficiently toward the optimal solution, reducing unnecessary computational iterations
Solution Approach 2:
The optimization process uses feedback from performance evaluation to continuously refine the freeform surface parameters. The system evaluates the distortion profile and optical aberrations, then adjusts the surface shape accordingly, creating a closed-loop optimization that converges to the desired performance
3Manufacturing precision
If multiple freeform surfaces are used to control optical aberrations, then the distortion profile can be precisely controlled, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The patent applies freeform surface technology selectively to specific optical elements where it provides the greatest benefit for distortion control. By introducing freeform surfaces at strategic locations rather than throughout the entire optical system, the design achieves precise distortion profile control while minimizing overall system complexity
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 method effectively creates an optical system with a freeform surface that precisely adjusts the 2D object-image mapping function, improving image quality and meeting optical requirements, such as a 120° field of view in both directions, by iteratively recalculating the freeform surface shape and optimizing other optical elements.
Implementation Method 1
an optical construction of a wide-angle lens having at least one freeform surface to better control the distortion profile
Data Source
AI summary
A method for designing a wide-angle optical system having at least one freeform optical surface without rotational symmetry to create a custom 2D object-image mapping. The method is based on iteratively adjusting the at least one freeform optical 2D surface shape to have the exact 2D object-image mapping required and then adjusting the optical element surfaces to meet the other required optical specifications. The iterative method is applied until both the desired 2D object-image mapping and the other required optical specifications are reached.