Triangular Cross-Section Light Guide for Motor Vehicle Headlights
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In motor vehicle headlights, the cylindrical shape of light guides often results in gaps between the edges of the window and the light guide, leading to light leaks and hot spots, which degrade the appearance of the device.
Innovation Solution
The output face of the light guide is bordered by two flat flanks forming an obtuse angle with the exit face, and the window's lateral edges extend in inclined planes parallel to the light guide's sides, ensuring a reduced play between the window and the light guide, thus minimizing light leaks and hot spots.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a cylindrical light guide is used, then the light guide can propagate light effectively, but gaps form between the window edges and light guide, causing light leaks and hot spots
Solution Approach 1:
The invention transitions from a cylindrical light guide to a light guide with a triangular cross-section. This geometric change allows the light guide to fit more precisely within the window structure, eliminating gaps that cause light leaks and hot spots while maintaining effective light propagation through the modified shape.
Solution Approach 2:
The triangular cross-section introduces asymmetry in the light guide geometry, allowing one face to be positioned flush with the window's outer surface while the other faces are angled. This asymmetric configuration optimizes the fit between the light guide and window structure, preventing light leakage without compromising light propagation efficiency.
2Object-affected harmful factors
If the light guide exit face is positioned flush with the window, then light leaks are reduced, but the installation precision requirement increases
Solution Approach 1:
The light guide is pre-configured with a triangular cross-section during manufacturing, with one face specifically designed to be positioned flush with the window's outer surface. This preliminary geometric preparation simplifies the installation process and reduces the precision required during assembly, as the flush-fit configuration is built into the light guide's structure.
Solution Approach 2:
The triangular cross-section creates different local geometries on different faces of the light guide. One face is configured to be flush with the window surface, while the other faces are angled. This local differentiation allows the flush-fit requirement to be met at the critical interface without requiring high precision across the entire light guide structure.
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 ensures a flush emergence of the light guide's exit face with the window, reducing light leaks and hot spots, thereby enhancing the aesthetic appearance of the device whether it is on or off.
Implementation Method 1
one of which is a reflective face to reflect the light
Implementation Method 2
the light rays emitted by this source propagate by total internal reflection along the length of the guide towards its opposite end
Data Source
Figure 1~4
AI summary
The invention concerns a light guide (10) having an elongate shape with an inlet end for light to enter and two opposing lateral faces (13, 14), including a reflection face that forms a series of prisms (15) of which the apexes (16) are flat, and an outlet face for the light guide. According to the invention, the outlet face of the light guide is planar and extends in a plane parallel to the front wall of the support that houses it.