Solid State Lighting Device with Wavelength Converting Light Guide
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional projection lighting systems face challenges in achieving high-intensity, small etendue green light sources, which are essential for applications like video projectors and automotive lighting, where existing SSL devices fall short in terms of power output and color gamut.
Innovation Solution
The development of an SSL lighting device with a housing and an elongated light guide containing wavelength converting materials, where SSL light sources emit light in one wavelength range that is absorbed and converted within the light guide, providing a high-intensity and high-power green light source with reduced etendue, and scalable output without increasing the light guide's etendue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If multiple SSL light sources are combined to increase power output, then light intensity and power output are improved, but device complexity increases
Solution Approach 1:
Multiple SSL light sources are combined within a single housing to increase power output. The light sources are arranged to emit light into the housing where it is collected and guided through a light guide, merging their output into a single high-intensity beam while maintaining manageable device complexity through integrated design.
Solution Approach 2:
A light guide acts as an intermediary component that collects light from multiple SSL light sources and guides it to the output. This mediator enables the combination of multiple light sources without directly coupling them, simplifying the overall device architecture while achieving high power output.
2Illumination intensity
If the light guide is placed close to SSL light sources to maximize light collection, then light intensity is improved, but heat impact on the light guide increases
Solution Approach 1:
The housing with reflective inner surface serves as an intermediary that redirects light from SSL light sources to the light guide without requiring direct contact. This allows effective light collection while maintaining thermal separation between the heat-generating light sources and the light guide.
Solution Approach 2:
The device is segmented into distinct functional zones: a housing containing the SSL light sources that generates heat, and a separate light guide that transmits light but is thermally isolated. This spatial segmentation allows optimization of each component for its specific function without compromising the other.
3Illumination intensity
If the emitting portion surface area is reduced to decrease etendue, then etendue is improved, but light intensity may be compromised
Solution Approach 1:
Light from multiple SSL light sources is merged within the housing and concentrated into a single small emitting portion of the light guide. This combining approach allows the system to achieve low etendue at the output while the cumulative power from multiple sources maintains high light intensity despite the reduced emitting surface area.
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 configuration enhances light intensity and power output beyond that of single SSL light sources, maintains efficiency by minimizing heat impact on the light guide, and allows for increased cooling and reduced attenuation through total internal reflection, resulting in a compact, high-power SSL lighting device.
Implementation Method 1
a wavelength converting material for converting light in a first wavelength range to light in a second wavelength range
Implementation Method 2
a part of the converted light is waveguided inside the light guide and emitted through the portion for emitting light
Data Source
AI summary
An SSL lighting device (1) comprising a housing (2), which has a reflective inner surface (3), and an elongated light guide (6) which includes a wavelength converting material (10) for converting light in a first wavelength range to light in a second wavelength range. The elongated light guide (6) comprises two ends (7a, 7b), a portion for receiving light (18) and a portion for emitting light (19). The portion for receiving light (18) is arranged inside the housing (2) and the portion for emitting light (19) is arranged outside the housing (2) and at least one of the two ends (7a, 7b) forms the portion (19) for emitting light. The SSL lighting device (1) also comprises a plurality of SSL light sources (4) arranged inside the housing (2) at a distance from the elongated light guide (6). A part of the light emitted from the plurality of SSL light sources (4) into the housing (2) enters the light guide (6) via the portion for receiving light (18) and is absorbed and converted by the wavelength converting material (10). By enclosing the light sources (4) and a portion of the light guide (6) inside a housing (2) with a reflective inner surface (3) and by having a wavelength conversion process occurring inside the light guide (6), this construction enables light from several light sources (4) to be used for providing a single high-intensity and high-power light source.