Sectional Mirror Light Compression for Projector Brightness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current image projectors face a tradeoff between lamp lifetime and brightness, with single lamp solutions offering longer life but lower intensity, and multiple lamp systems providing inefficiencies in light combination, resulting in suboptimal performance in terms of brightness and power consumption.
Innovation Solution
The use of mirrors to compress light from multiple sources into a single pupil of an imaging device, with stepped mirror surfaces having different angles to optimize light reflection and distribution, allowing for increased brightness while maintaining compactness and long lifetime.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If multiple lamps are used to increase brightness, then illumination intensity is improved, but light combination efficiency deteriorates
Solution Approach 1:
The system divides the light collection and compression function into separate sections, with each lamp having its own dedicated mirror that compresses light into a specific region of the pupil. This segmentation allows efficient light collection from multiple lamps without the efficiency losses associated with combining light from multiple sources in conventional systems.
Solution Approach 2:
The invention utilizes the spatial dimension of the pupil by compressing light from multiple lamps into different regions (e.g., first half and second half) of the same pupil. This dimensional approach allows multiple light sources to contribute effectively to the final image without interfering with each other, thereby improving both brightness and efficiency.
2Illumination intensity
If Xenon lamps are used to achieve high brightness, then illumination intensity is improved, but lifetime deteriorates
Solution Approach 1:
The system changes the key parameter of light flux density by using stepped mirrors to compress light from multiple lower-wattage lamps into the pupil, achieving the same or higher brightness levels that would otherwise require high-wattage Xenon lamps. This parameter change allows the use of longer-lived lamp technology while maintaining high brightness performance.
Solution Approach 2:
The invention merges the light output from multiple lamps through a unified optical path using stepped mirrors, combining their contributions into a single coherent light beam that illuminates the pupil. This merging effect achieves high brightness equivalent to or exceeding Xenon lamp performance while using lamps with significantly longer operational lifetimes.
3Illumination intensity
If light compression is performed to increase brightness, then illumination intensity is improved, but light loss increases
Solution Approach 1:
The stepped mirrors are designed with locally optimized surface properties, where different regions of the mirror have different angles and orientations tailored to reflect and compress light from specific lamp regions into corresponding pupil regions. This local quality optimization ensures maximum light transmission efficiency while achieving the desired compression and brightness enhancement.
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 achieves light flux levels 1.5 times or more than existing systems, reducing power and material costs while enhancing brightness and extending lamp life, thereby improving overall projector performance.
Implementation Method 1
A first reflective surface reflects EM radiation from the first source. A second reflective surface reflects EM radiation from the second source.
Implementation Method 2
The compression is accomplished by regions (e.g. sections) of the mirror having different angles with respect to the pupil.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Image projectors with increased light intensity and methods for providing brighter images are provided. Image projectors, described herein, can provide the brightness while still providing any or all of compactness, low power consumption, and long lifetime. To increase brightness, sectional mirrors are used to respectively compress the light from two light sources into a single pupil (e.g. an aperture) of an imaging device. The compression can be accomplished by regions (e.g. sections) of the mirror having different angles with respect to the pupil. Relatively little light may be lost in the compression since minima for a light intensity pattern from a light source may occur between the regions that reflect the light.