Annular Optical Element Stray Light Attenuation via Protrusion Structures
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional annular optical elements used in compact imaging lens assemblies for portable devices suffer from high reflectivity, leading to ineffective stray light attenuation, which limits image quality and fails to meet the requirements of high-end optical systems.
Innovation Solution
An annular optical element with a surface featuring alternately arranged protrusion and separation structures, formed by injection molding, which reduces reflectivity and enhances image quality by effectively attenuating stray light.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional annular optical element with a smooth and bright surface is used, then the manufacturing is simple, but the reflectivity is high causing ineffective stray light attenuation
Solution Approach 1:
The patent applies local quality by creating protrusion structures at specific locations on the inner annular surface. These localized structures have different optical properties (lower reflectivity) compared to the surrounding smooth areas, thereby reducing stray light reflection in critical regions while maintaining manufacturing simplicity through injection molding
Solution Approach 2:
The patent segments the inner annular surface into multiple protrusion structures arranged in circumferential rows. This segmentation creates multiple small reflective surfaces that scatter stray light more effectively than a single smooth surface, while the modular structure can be integrated into the injection molding process
2Object-generated harmful factors
If atomized surface treatment is applied to reduce reflectivity, then stray light attenuation is improved, but the effect is still limited and cannot satisfy high-end optical requirements
Solution Approach 1:
The patent uses curved protrusion structures with specific geometric shapes (circular arcs, spherical segments) on the inner annular surface. These curved surfaces scatter stray light more effectively than flat or atomized surfaces by redirecting light rays in multiple directions, achieving superior stray light attenuation required for high-end optical systems
Solution Approach 2:
The patent transitions from two-dimensional atomized surface treatment to three-dimensional protrusion structures. By adding vertical dimension and creating raised structures with specific heights and shapes, the patent achieves more effective stray light control that cannot be obtained through surface coating alone
3Object-generated harmful factors
If protrusion structures with specific height differences are created on the inner annular surface, then stray light attenuation is significantly enhanced, but the manufacturing complexity increases
Solution Approach 1:
The patent designs protrusion structures with specific geometric relationships (circles centered on the optical axis with defined radius ratios). These self-similar, repeating patterns can be automatically generated through injection molding without requiring complex post-processing or assembly, allowing the structure to serve its own manufacturing needs
Solution Approach 2:
The patent controls stray light attenuation by adjusting specific parameters of the protrusion structures (height H, radius ratios, spacing) rather than changing the fundamental structure. This parameter-based approach allows optimization of optical performance while maintaining manufacturing feasibility through standard injection molding processes
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 proposed annular optical element design significantly improves image quality by effectively reducing stray light reflection, meeting the demands of high-end optical systems and enabling efficient mass production.
Implementation Method 1
The inner annular surface includes a plurality of protrusion circles surrounding the central axis and arranged along a direction from the first side surface towards the second side surface. Each of the protrusion circles includes a plurality of protrusion structures and a plurality of separation structures, and the protrusion structures and the separation structures are alternately arranged to surround the central axis.
Implementation Method 2
An annular optical element with a surface featuring alternately arranged protrusion and separation structures, formed by injection molding, which reduces reflectivity and enhances image quality by effectively attenuating stray light.
Data Source
AI summary
An annular optical element includes a first side surface, a second side surface, an outer annular surface and an inner annular surface. The outer annular surface connects the first side surface and the second side surface, and surrounds a central axis of the annular optical element. The inner annular surface connects the first side surface and the second side surface, surrounds the central axis, and is closer to the central axis than the outer annular surface is to the central axis. The inner annular surface includes a plurality of protrusion circles surrounding the central axis and arranged along a direction from the first side surface towards the second side surface. Each of the protrusion circles includes a plurality of protrusion structures and a plurality of separation structures, and the protrusion structures and the separation structures are alternately arranged to surround the central axis.