Vehicle Headlamp Light Module Laser Safety Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The use of laser light sources in motor vehicle headlights poses safety risks due to the emission of coherent, monochromatic light, which can be dangerous to human eyes, and requires conversion to white light, with photoluminescence elements being critical for safety but vulnerable to mechanical damage or removal, potentially leading to unconverted laser beams escaping.
Innovation Solution
A light module with a laser light source, a photoluminescence element in the beam path to convert monochromatic light to white light, and a detection device to monitor radiation intensity, deactivating the laser source if intensity exceeds safety limits, ensuring the photoluminescence element is properly positioned and functional.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If laser light sources are used in motor vehicle headlights, then high radiation intensities and collimated light beams are achieved, but safety risks arise due to coherent monochromatic light potentially endangering human eyes
Solution Approach 1:
A photoluminescence element is introduced as an intermediary between the laser light source and the external environment. This element converts the dangerous coherent monochromatic laser light into safe incoherent polychromatic light through photoluminescence conversion, while maintaining the beneficial high radiation intensity and collimated beam properties for illumination purposes
Solution Approach 2:
The patent converts the potentially harmful coherent monochromatic laser light into beneficial safe polychromatic light. The photoluminescence element transforms the dangerous properties (coherence, monochromaticity) into desirable properties (incoherence, polychromaticity) while preserving the high intensity and directionality needed for effective headlight illumination
2Object-affected harmful factors
If photoluminescence elements are used to convert laser light to white light, then safety is improved by preventing dangerous laser beams from escaping, but the photoluminescence element becomes vulnerable to mechanical damage or removal
Solution Approach 1:
A detection device is implemented that continuously monitors the beam path for unconverted laser light. When the photoluminescence element is damaged or removed, the detection device detects the presence of unconverted laser beams and triggers an alarm or shutdown signal, providing real-time feedback on the operational status of the safety-critical photoluminescence element
Solution Approach 2:
The detection device is positioned in the beam path before the photoluminescence element to detect unconverted laser light. This preliminary detection allows the system to identify potential safety issues before dangerous light can escape, enabling preventive action through alarm or shutdown signals
3Adaptability or versatility
If photoluminescence elements are placed in the beam path for light conversion, then monochromatic laser light is converted to polychromatic light, but the device complexity increases due to additional safety monitoring requirements
Solution Approach 1:
The detection device serves multiple functions: it monitors for unconverted laser light, detects photoluminescence element integrity, triggers alarm signals, and can shutdown the laser source. This multi-functionality consolidates several safety mechanisms into a single integrated device, reducing overall system complexity despite the added safety monitoring requirements
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 effectively converts potentially dangerous laser light into safe white light and ensures operational reliability by detecting and preventing hazardous laser beam emission, maintaining safety and preventing damage to the light module.
Implementation Method 1
A photoluminescence element is provided in the beam path, which is arranged in such a way that the primary light beam that can be emitted with the laser light source strikes the photoluminescence element, and which is designed in such a way that the incident primary light beam can emit a secondary light distribution using photoluminescence.
Implementation Method 2
The light module has at least one detection device, which can be used to determine when the radiation intensity of light bundles, which run in the beam path after the photoluminescent element in the primary solid angle area around the primary beam axis, exceeds a safety limit.
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
The invention relates to a light module for motor vehicle headlamps (10), comprising a laser light source (12) for emitting a primary light bundle (14) in a primary spatial angle sector about a primary beam axis (16), a photoluminescent element (18), which is arranged in such a way that the primary light bundle (14) that can be emitted by means of the laser light source (12) hits the photoluminescent element (18) and which is designed in such a way that a secondary light distribution (20) can be emitted as a result of the incident primary light bundle (14) by utilizing photoluminescence. The light module also comprises an emission optical device (22), which is designed in such a way that the secondary light distribution (20) can be converted into an emission light distribution of the light module (10). A detecting device (34) is provided, which is designed and arranged in such a way that the detecting device can detect when the radiation intensity of light bundles that extend in the beam path downstream of the photoluminescent element (18) in the primary spatial angle sector about the primary beam axis (16) exceeds a safety limit.