Motor Vehicle Headlamp Using Digital Micromirror Device
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current headlamps with digital micromirror devices (DMD) or LED matrix systems lack efficient light distribution and luminous intensity, particularly in achieving inhomogeneous light distributions using differing luminance light sources.
Innovation Solution
The use of distinct light sources, such as High-Luminance LEDs (HL-LEDs) and laser diodes, with different areas of incidence on a DMD chip, allowing for combined light functions like high beam, building site lighting, and autonomous driving features, while optimizing optic means for each source to enhance illumination efficiency and compact design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If laser light sources are used to provide high luminous intensity, then the luminous intensity is improved, but the system efficiency deteriorates due to high cost and insufficient total light flux
Solution Approach 1:
The patent combines two different light sources (laser light source and HL-LED) with different luminance characteristics into a single headlamp system. The laser light source provides high luminous intensity for focused illumination, while the HL-LED provides high luminous flux for overall illumination, merging their complementary strengths to achieve both high intensity and high system efficiency
2Quantity of substance
If HL-LEDs are used to provide high luminous flux, then the luminous flux is improved, but the luminance deteriorates due to lower luminance compared to laser light sources
Solution Approach 1:
The patent applies local quality by directing different light sources to different areas of the DMD chip with different area ratios. The laser light source illuminates a smaller central area with high luminance for high beam functions, while the HL-LED illuminates a larger area with lower luminance for general illumination, allowing each light source to operate in its optimal luminance range
3Measurement precision
If DMD chips are fully illuminated for high resolution, then the resolution is improved, but the luminous intensity deteriorates due to dilution of light across the entire surface
Solution Approach 1:
The patent applies partial action by having the laser light source illuminate only a portion of the DMD chip active surface (central area) rather than the entire surface. This concentrated partial illumination maintains high luminous intensity for high beam functions while the HL-LED provides supplementary illumination to achieve full chip utilization for resolution 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
This approach enables effective generation of inhomogeneous light distributions, achieving high luminous intensity and resolution with reduced thermal and luminous flux losses, meeting legal light distribution limits and providing a cost-effective, compact headlamp design.
Implementation Method 1
at least one first light source (2) having a first area ratio, wherein an exit surface of the at least one first light source (2) is projected on the digital micromirror device (1) in such a way that the digital micromirror device (1) is illuminated by the light emitted by the at least one first light source (2) over a large area
Implementation Method 2
at least one second light source (3) having a second area ratio, wherein an exit surface of the at least one second light source (3) is focused onto converter means (6), by means of which the light emitted by the at least one second light source (3) is transformed at least partially into light of a different wavelength
Implementation Method 3
the light converted by the converter means (6) is projected onto the digital micromirror device (1) in such a way that the light converted by the converter means (6) illuminates a smaller area, in particular a central area, of the digital micromirror device (1) with high luminance
Implementation Method 4
DMD chip, which can be used to generate a desired light distribution
Data Source
AI summary
A headlamp, and in particular a headlamp for a motor vehicle, comprising a digital micromirror device which reflects light hitting it so that it exits at least partially from the headlamp when the headlamp is operated. The headlamp also includes at least one first light source which emits light with a first luminance, and which hits the digital micromirror device at least partially when the headlamp is operated. The headlamp also includes at least one second light source emitting light when the headlamp is operated, and having a second luminance which is different from the first luminance. The light emitted from the at least one second light source hits, at least partially, the digital micromirror device. The areas of incidence of the light emitted by the light sources on the digital micromirror device overlap at least partially. On the digital micromirror device, the range of incidence of the light emitted by the at least one first light source differs from the range of incidence of the light emitted by the at least one second light source.