Optical Cavity with Substrate for LED Thermal Management
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing optical systems with semiconductor light-emitting devices and wavelength converting materials face inefficiencies due to heating issues and chemical compatibility problems, which affect the quantum efficiency and color balance of the emitted light.
Innovation Solution
An optical cavity design where semiconductor light-emitting devices are attached to a substrate with wavelength converting materials disposed on or near the substrate, allowing for efficient light conversion and heat dissipation, while maintaining a reflective structure to direct light and minimize interaction with the LEDs, thereby optimizing the light spectrum and reducing thermal stress on the wavelength converting materials.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If wavelength converting materials are placed directly on LED chips, then light conversion efficiency is improved, but thermal stress and chemical compatibility problems worsen
Solution Approach 1:
The patent introduces a substrate as an intermediary component between the LED chips and wavelength converting materials. This substrate serves as a thermal management platform that conducts heat away from the conversion materials, preventing thermal stress and chemical compatibility issues while maintaining efficient light conversion. The substrate acts as a mediator that decouples the thermal and chemical interaction between LEDs and phosphors.
Solution Approach 2:
The patent transitions from a two-dimensional planar arrangement where phosphors are directly on LED chips to a three-dimensional structure with a substrate providing thermal conduction pathways. This dimensional change allows heat to be conducted in multiple directions through the substrate, improving thermal management while maintaining optical efficiency.
2Temperature
If phosphor is placed on the cover plate, then thermal stress on phosphor is reduced, but light recycling efficiency decreases
Solution Approach 1:
The substrate acts as an intermediary that provides both thermal management and optical functionality. It conducts heat away from the phosphor while its reflective properties direct unconverted light back toward the LED chips, enabling simultaneous thermal protection and light recycling without requiring phosphor to be placed on the cover plate.
3Stability of the object's composition
If multiple phosphor types are used to achieve color balance, then color rendering improves, but system complexity increases
Solution Approach 1:
The patent combines multiple wavelength converting materials on a single substrate, merging their functions into one integrated platform. This consolidation achieves color balance through multiple phosphors while reducing overall system complexity compared to separate phosphor layers or components, as the substrate provides unified thermal and optical management for all conversion materials.
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 the efficiency of light conversion, maintains high quantum efficiency, and improves color balance by keeping the wavelength converting materials cool and reducing thermal stress, resulting in improved performance and longer device lifespan.
Implementation Method 1
III-nitride devices may be combined with wavelength converting materials such as phosphors, as is known in the art, to form white light or light of other colors
Implementation Method 2
maintaining a reflective structure to direct light and minimize interaction with the LEDs
Implementation Method 3
allowing for efficient light conversion and heat dissipation, while maintaining a reflective structure to direct light and minimize interaction with the LEDs, thereby optimizing the light spectrum and reducing thermal stress on the wavelength converting materials
Data Source
Figure 1~4
Figure 5~7
AI summary
Embodiments of the invention include a semiconductor light emitting diode attached to a substrate. A first region of wavelength converting material is disposed on the substrate. The wavelength converting material is configured to absorb light emitted by the semiconductor light emitting diode and emit light at a different wavelength. In the first region, the wavelength converting material coats an entire surface of the substrate. The substrate is disposed proximate a bottom surface of an optical cavity. A second region of wavelength converting material is disposed proximate a top surface of the optical cavity.