Lighting Device Transparent Stabilizer Element Thermal Expansion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lighting devices with close-packed light-emitting elements, such as LEDs in automotive headlights, face thermal stress issues due to uneven heat distribution, leading to deformation and misalignment of light guides, which reduces light collimation effectiveness and results in an inhomogeneous light pattern.
Innovation Solution
A lighting device design featuring light-emitting elements on a substrate with optically contacted light guides and a transparent stabilizer element in mechanical contact with the lens, which defines the light exit side and limits thermal expansion, maintaining alignment and reducing thermal sensitivity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If light guides are arranged close to light-emitting elements to improve light output, then light coupling efficiency is improved, but thermal stress causes misalignment and deformation
Solution Approach 1:
The patent divides the light guide structure into multiple independent finger-shaped light guides, each associated with a specific light-emitting element. This segmentation allows each light guide to be independently positioned and stabilized, reducing the impact of thermal stress on overall alignment while maintaining close proximity for efficient light coupling.
Solution Approach 2:
The patent introduces a substrate as an intermediary structure that mechanically supports both the light-emitting elements and the finger-shaped light guides. This intermediary provides a stable reference frame that maintains precise alignment between light sources and light guides even under thermal stress, preventing misalignment while allowing close packing for high light output.
2Illumination intensity
If finger-shaped collimators are used to improve light directionality, then beam quality is improved, but thermal expansion causes bulging and tilting
Solution Approach 1:
The patent applies different structural characteristics to different parts of the lighting device. The finger-shaped light guides have specific local geometries optimized for collimation, while the substrate provides a rigid global structure. This local quality differentiation allows the light guides to maintain their collimating function while the substrate prevents thermal bulging and tilting.
Solution Approach 2:
The patent changes the physical parameters of the system by using materials with appropriate thermal expansion coefficients and designing the substrate with sufficient mechanical stiffness. These parameter changes ensure that while local thermal expansion occurs in the light guides, the overall structure maintains its shape and orientation, preventing bulging and tilting.
3Adaptability or versatility
If multiple light-emitting elements are arranged in a matrix to provide adaptive lighting, then functionality is improved, but heat load increases causing thermal stress
Solution Approach 1:
The substrate serves multiple functions simultaneously: it provides mechanical support for the matrix arrangement of light-emitting elements, acts as a thermal management platform, maintains precise alignment of multiple finger-shaped light guides, and provides a stable reference frame for the entire adaptive lighting system. This multi-functionality allows the matrix configuration to achieve adaptive lighting capabilities without being overwhelmed by heat load.
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 transparent stabilizer element effectively stabilizes the lens and light guides, maintaining alignment and reducing thermal sensitivity, thereby enhancing light collimation and pattern homogeneity even under high heat loads.
Implementation Method 1
light guides guiding light from the light-emitting elements towards a lens
Implementation Method 2
the heat load leads to thermal stresses inside the lighting device, such that light guides may deform and may be displaced relative to the light-emitting elements
Data Source
AI summary
The present disclosure relates to a lighting device comprising light-emitting elements such as light-emitting diodes arranged on a substrate. The object to provide a lighting device comprising multiple light-emitting elements and light guides, wherein the thermal sensitivity of the lighting device is reduced in a particularly simple manner, is solved in that the lighting device comprises: a lens with a light entry side and a light exit side; light guides, each light guide being arranged in optical contact to at least one of the light-emitting elements and being configured to guide light emitted by the at least one of the light-emitting elements towards the light entry side of the lens; and a transparent stabilizer element being arranged in mechanical contact to the light exit side of the lens, wherein the transparent stabilizer element is configured to define the shape of the light exit side of the lens at least in regions. The invention further refers to a method for producing a lighting device.