Automotive Light Guide Structure for Distinct Signaling and Headlight

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional automotive lighting systems face complexity and increased bulkiness when combining signaling and lighting functions, making it difficult to meet statutory requirements and necessitating separate modules and modified lenses for each variant, which increases manufacturing costs and space requirements.

Innovation Solution

A unified lighting and signaling device incorporating a main light source with a front light guide and a side light guide, where the front light guide features smooth and irregular surfaces with patterns to separate signaling and main light beams, allowing for integration of functions in a single module without modifying the outer lens, enabling clear distinction and standardization across different vehicle variants.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Area of moving object

If signaling and lighting functions are combined in one headlamp, then the number of separate devices is reduced, but it becomes difficult to ensure signaling light and headlight are clearly distinguishable and increases device complexity

Engineering Contradiction:
Improvespace occupied by lighting deviceVSAvoidcomplexity of lighting module
Core Design Contradiction:
Area of moving objectVSDevice complexity

Solution Approach 1:

The patent divides the light guide into distinct functional zones: a first light guide portion for signaling light and a second light guide portion for headlight. This segmentation allows each portion to be optimized for its specific function while being part of a unified structure, resolving the contradiction between integration and functional distinction.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent applies different optical properties to different regions of the light guide. The first light guide portion has optical properties optimized for signaling light transmission, while the second light guide portion has optical properties optimized for headlight transmission. This local differentiation enables clear functional distinction within an integrated structure.

Inventive Principle:
Principle #3Local quality

2Reliability

If separate signaling module is kept away from main light, then signaling and lighting functions can be performed, but the headlamp becomes bulky and increases weight

Engineering Contradiction:
Improvefunctional distinctionVSAvoidweight of headlamp
Core Design Contradiction:
ReliabilityVSWeight of stationary object

Solution Approach 1:

The patent merges the signaling module and main light module into a single integrated headlamp structure with a unified light guide. The signaling light source and main light source are positioned within the same housing and share common optical components, eliminating the need for separate signaling units and reducing overall weight.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The light guide serves multiple functions: it transmits both signaling light and headlight, and can be configured to perform different lighting functions (low beam, high beam, fog light) depending on the activation of different light sources. This multi-functionality eliminates the need for separate dedicated signaling hardware.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Illumination intensity

If outer lens is modified to neutralize refraction for each vehicle variant, then light direction can be controlled, but manufacturing complexity and costs increase

Engineering Contradiction:
Improvelight direction controlVSAvoidmanufacturing complexity
Core Design Contradiction:
Illumination intensityVSEase of manufacture

Solution Approach 1:

Instead of modifying the outer lens for each vehicle variant, the patent inverts the approach by modifying the light guide's optical properties to achieve the desired light direction. The light guide is designed with specific optical characteristics that control light propagation, eliminating the need for custom outer lens modifications for different variants.

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The patent controls light direction by changing the optical parameters of the light guide rather than the outer lens. By adjusting the refractive index, thickness, or surface geometry of the light guide, the light propagation direction can be controlled to meet different vehicle variant requirements without remanufacturing the outer lens.

Inventive Principle:
Principle #35Parameter changes

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 allows for clear separation of signaling and lighting functions, reducing bulkiness and manufacturing complexity, enabling a compact, standardized lighting system that meets regulatory requirements without the need for separate signaling units, thus enhancing design flexibility and reducing costs.

Implementation Method 1

a front light guide that is a flat light guide comprising two main surfaces separated by edges, the light guide and its main surfaces being arranged in front of the lighting module and transversally to the main direction

Methodology Applied
Scientific EffectLight transmission: Light

Implementation Method 2

the direction of the light rays when going through the outer lens is not impacted by the refraction

Methodology Applied
Scientific EffectRefraction: Refraction

Implementation Method 3

the side light guide is arranged such that the light transmitted from the side light guide is different from the light transmitted from the front light guide

Methodology Applied
Scientific EffectLight transmission: Light

Data Source

PatentEP4390215A1A signaling and/or lighting device for a motor vehicle
Publication Date: 2024.06.26 VALEO VISION SA
  • EP4390215A1 patent drawingFigure 1
  • EP4390215A1 patent drawingFigure 2a~2b
  • EP4390215A1 patent drawingFigure 2c~3b

AI summary

The present invention pertains to an indicating and/or lighting device 100 for a motor vehicle. The device 100 comprises a lighting module 102 having a main light source 104 and emitting a main light beam in a main direction. The device 100 comprises a front light guide 106 that is a flat light guide comprising two main surfaces 120 separated by edges 122. The front light guide 106 and its main surfaces 120 being arranged in front of the lighting module 102 and transversally to the main direction. At least one of the said main surfaces 120 comprises smooth surfaces portions 206 and irregular portions 208 covered by plurality of roughnesses with at least one pattern. Further, the device 100 comprises at least one side light guide 108 arranged at a side of the lighting module 102 including top and bottom. The side light guide 108 is arranged such that the light transmitted from the side light guide 108 is different from the light transmitted from the front light guide 106.