Anamorphic Headlamp Optics for Aspect Ratio Mismatch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Automotive headlamps face challenges in achieving high resolution and efficient light distribution due to aspect ratio mismatches between video projection systems and headlamp requirements, leading to losses in brightness and resolution.
Innovation Solution
The use of spatial light modulators, such as digital micro-mirror devices (DMDs), in conjunction with anamorphic lenses to reshape the light beam aspect ratio and maintain high etendue, allowing for center-peaked light distribution without the need for homogenizers, thereby enhancing brightness and resolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If video projection systems are used for headlamps, then light distribution can be controlled, but brightness and resolution are reduced due to aspect ratio mismatch
Solution Approach 1:
The patent applies asymmetry by using anamorphic lenses with different focal lengths in the horizontal and vertical directions (e.g., 4mm horizontal and 2mm vertical). This asymmetric optical design transforms the circular light beam into an elliptical shape that matches the aspect ratio of the DMD device, thereby resolving the aspect ratio mismatch between video projection systems and headlamp requirements while maintaining high brightness and resolution
2Illumination intensity
If homogenizers are used to achieve uniform light distribution, then illumination uniformity improves, but light loss increases
Solution Approach 1:
The patent extracts and removes the homogenizer component from the optical system. Instead of using a homogenizer to achieve uniform light distribution, the invention relies on the inherent non-uniform center-peaked light distribution from the LED source combined with the anamorphic lens shaping, thereby eliminating the light losses associated with homogenizers while still achieving the desired illumination pattern
3Device complexity
If low resolution pixel arrays are used, then device complexity is reduced, but driver distraction increases due to jerky beam movement
Solution Approach 1:
The patent changes the resolution parameter by utilizing the high pixel count capability of modern DMD devices (e.g., 1920x1080 or higher). This high resolution enables smooth, continuous beam movement and precise positioning of light patterns on the roadway, eliminating the jerky motion that would occur with low resolution arrays while maintaining manageable device complexity through the use of成熟的DMD technology
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 results in a more efficient and brighter light projection with a higher aspect ratio, suitable for headlamp applications, while avoiding the inefficiencies associated with traditional video projection systems.
Implementation Method 1
At least one of the illumination optics and the projection optics includes an anamorphic lens to shape the light beam
Data Source
AI summary
In described examples of a headlamp to project a beam of light from a lens, the headlamp includes: an illumination module to output a light beam to an illumination path; and illumination optics to receive the light beam and to provide illumination to a programmable spatial light modulator. The programmable spatial light modulator is arranged to receive the illumination and to output non-uniform illumination as patterned light to projection optics. The projection optics are arranged to receive the patterned light and to output the patterned light through the lens. At least one of the illumination optics and the projection optics includes an anamorphic lens to shape the light beam.