Truncated Parabolic Reflector Lighting System
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing lighting systems using semiconductor light-emitting devices often fail to provide controlled light emissions with uniform color points and brightness, and they can suffer from heat-induced degradation of lumiphors, leading to unstable color points and non-uniform brightness.
Innovation Solution
A lighting system comprising a semiconductor light-emitting device, a visible light reflector, and a volumetric lumiphor, where the lumiphor is positioned between the light source and the reflector to convert light emissions, with the reflector configured to redirect and transmit light emissions, thereby achieving controlled light distribution and protecting the lumiphor from heat.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If the lumiphor is positioned close to the semiconductor light-emitting device for efficient light conversion, then the light conversion efficiency is improved, but the lumiphor suffers from heat-induced degradation
Solution Approach 1:
The patent introduces a visible light reflector as an intermediary component positioned between the semiconductor light-emitting device and the volumetric lumiphor. The reflector redirects visible light emissions toward the lumiphor, enabling efficient light conversion while maintaining a physical distance that protects the lumiphor from heat generated by the semiconductor device. This mediator approach resolves the contradiction by decoupling the light transfer path from the heat transfer path.
2Illumination intensity
If the reflector is designed to reflect all visible light for maximum luminous flux, then the brightness is improved, but the color uniformity deteriorates due to heat concentration
Solution Approach 1:
The patent applies local quality by creating a spatially non-uniform reflector design where different regions have different reflectivity characteristics. The reflector includes a first portion with higher reflectivity and a second portion with lower reflectivity, allowing selective redirection of light while distributing heat concentration across different zones. This prevents localized thermal degradation of the lumiphor while maintaining overall luminous flux.
Solution Approach 2:
The patent employs a multi-path light redirection strategy where visible light emissions are reflected multiple times through different portions of the reflector before reaching the lumiphor. This 'skipping' approach allows light to traverse longer paths while heat is distributed across multiple reflection points, preventing concentration at any single location and thereby maintaining color uniformity.
3Illumination intensity
If the semiconductor light-emitting device emits high intensity light for better visibility, then the brightness is improved, but the heat generation increases causing lumiphor degradation
Solution Approach 1:
The visible light reflector serves as a thermal mediator that separates the high-intensity light source from the lumiphor. It allows high-intensity visible light to be redirected efficiently to the lumiphor while the physical distance and reflective geometry prevent direct heat transfer, thus decoupling light intensity from temperature at the lumiphor location.
Solution Approach 2:
The patent extracts the visible light component from the total electromagnetic radiation emitted by the semiconductor device and redirects it separately from the heat component. By using a visible light reflector that specifically targets visible wavelengths, the system extracts useful light energy while leaving thermal radiation to dissipate independently, thereby reducing heat concentration at the lumiphor.
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 system produces light emissions with uniform color points and brightness, is aesthetically pleasing, and protects the lumiphor from heat-induced degradation, resulting in stable and long-lasting performance.
Implementation Method 1
the volumetric lumiphor is configured for converting some of the light emissions having the first spectral power distribution into light emissions having a second spectral power distribution being different than the first spectral power distribution
Implementation Method 2
the reflective surface of the visible light reflector is configured for causing a portion of the light emissions having the first and second spectral power distributions to be reflected by the visible light reflector
Implementation Method 3
the visible light reflector is configured for permitting another portion of the light emissions having the first and second spectral power distributions to be transmitted through the visible light reflector along the central axis
Data Source
AI summary
Lighting system including light source having semiconductor light-emitting device configured for emitting light having first spectral power distribution along central axis. System includes volumetric lumiphor located along central axis configured for converting some light emissions having first spectral power distribution into light emissions having second spectral power distribution. System may include visible light reflector having reflective surface and being spaced apart along central axis with volumetric lumiphor between semiconductor light-emitting device and visible light reflector. Reflective surface may be configured for causing portion of light emissions to be reflected by visible light reflector. Exterior surface of volumetric lumiphor may include concave exterior surface configured for receiving a mound-shaped reflective surface of visible light reflector. Volumetric lumiphor may have exterior surface that includes: concave exterior surface forming gap between semiconductor light-emitting device and volumetric lumiphor; or convex or concave exterior surface located away from and surrounding central axis. Related lighting processes.