Annular Prism Lens Member for LED Light Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional Fresnel lenses face issues with light-entrance and reflection precision due to rounded prism edges during resin molding, leading to deteriorated luminance performance and increased lens thickness, as well as light loss and ring-shaped flare in LED lighting applications.
Innovation Solution
A lens member with annular prisms having facets at the edges between inner and outer surfaces, allowing for precise light refraction and reflection, and a protruding portion with facets on a conical shape to improve light distribution and reduce lens thickness, while incorporating a light-exit side with minute irregularities for enhanced directivity control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If a conventional Fresnel lens with sharp-edged prisms is used, then light refraction and reflection precision is improved, but manufacturing difficulty increases due to resin filling problems during molding
Solution Approach 1:
The patent changes the geometric parameter of the prism edge from a sharp angle to a rounded shape with a specific radius of curvature. This parameter modification allows resin to easily fill the mold during injection molding while maintaining sufficient light refraction and reflection precision, thus resolving the contradiction between manufacturing ease and optical precision.
2Reliability
If the reflecting surface is raised to reflect all entering light from a rounded light-entrance surface, then light reflection completeness is improved, but lens thickness increases
Solution Approach 1:
The patent optimizes the parameters of the rounded prism edges, specifically the radius of curvature, to achieve an optimal balance. By carefully selecting the rounding radius, the design ensures sufficient light reflection completeness while minimizing the increase in lens thickness, thus resolving the contradiction between reflection completeness and lens thickness.
3Use of energy by moving object
If a conventional TIR lens is used with LED light source, then light collection is improved, but ring-shaped flare is generated due to non-uniform light distribution
Solution Approach 1:
The patent applies different treatments to different regions of the lens. The central portion uses prisms with specific rounding to control light from the high-intensity central region of LED emission, while peripheral regions have different prism configurations. This local differentiation eliminates ring-shaped flare while maintaining overall light collection efficiency.
Solution Approach 2:
The patent modifies the prism parameters (edge rounding radius, prism angle, height) to optimize light distribution. By adjusting these parameters, the lens achieves uniform light output and eliminates ring-shaped flare while maintaining high light collection efficiency from the LED source.
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 enhances luminance performance along the central axis, reduces light loss, and achieves a more uniform light distribution, resulting in improved efficiency and appearance of LED optical products.
Implementation Method 1
a plurality of annular prisms 13 provided on a light-entry side 12... the inner annular surfaces 13a and the outer annular surfaces 13b being formed in a shape of Fresnel lens surface
Implementation Method 2
a part of the prisms of the Fresnel lens surface acting as a light-entrance surface is formed such that a part of the entering light rays are emitted from the light-exit surface after being totally internally reflected at the non-lens surface
Data Source
AI summary
A lens member includes at least one of the annular prisms including a facet at an edge between an inner annular surface and an outer surface of the at least one of the annular prisms. The prisms with facets may be provided at a central portion of the lens member and the facets are configured to refract light toward a light-exit side of the lens member.