Planarized Light Converter Coating for Higher Extraction and Lower Heat
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing light converters, particularly in phosphor wheels, face challenges in efficiency, output power, and temperature management, with PIS-type materials offering advantages like flexible color choices and simpler structures but requiring performance improvements without changing the light conversion layer type.
Innovation Solution
A light converter with a planarization layer and optical coating is introduced, where the planarization layer has a refractive index close to the light conversion layer, providing an optically smooth surface for the optical coating, which can be applied more readily and improves efficiency by 5% while reducing operating temperature by 9°C.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional LEDs are used to provide illumination, then the device can be manufactured with standard components, but the LEDs generate harmful blue light wavelengths that can damage the retina and suppress melatonin production
Solution Approach 1:
The patent introduces a down-converting element as an intermediary between the conventional LED and the human eye. This element absorbs harmful blue light wavelengths and converts them to safer wavelengths, allowing the use of standard LEDs while eliminating the harmful effects. The down-converting element acts as a mediator that transforms the harmful blue light into beneficial or neutral wavelengths.
Solution Approach 2:
The patent converts the harmful blue light emitted by conventional LEDs into useful illumination at safer wavelengths. By using a down-converting element, the harmful blue light is transformed into visible light at wavelengths that do not damage the retina or suppress melatonin, effectively turning a harmful property into a beneficial one.
2Illumination intensity
If the intensity of conventional LEDs is increased to provide sufficient illumination, then the illumination level improves, but the harmful blue light exposure and energy consumption increase
Solution Approach 1:
The down-converting element serves as an intermediary that allows the LED to operate at lower intensities while still providing sufficient illumination. The element converts a portion of the blue light to other wavelengths, effectively distributing the illumination across multiple wavelengths and reducing the intensity requirement of the source LED.
Solution Approach 2:
The patent changes the spectral parameters of the light by introducing a down-converting element with specific absorption and emission characteristics. This allows the system to achieve the same illumination level with lower LED intensity by utilizing the converted wavelengths from the down-converting element.
3Object-affected harmful factors
If down-converting elements are added to convert blue light to safer wavelengths, then harmful blue light is reduced, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The patent employs thin film down-converting elements that can be deposited directly onto the LED surface or substrate. This thin film approach minimizes the added complexity by using a lightweight, integrated structure rather than bulky discrete components, making the solution easier to manufacture despite the added functionality.
Solution Approach 2:
The down-converting element is merged with the LED structure, either as a coating on the LED chip or as an integrated layer in the light guide. This merging approach reduces device complexity by combining multiple functions (illumination and wavelength conversion) into a single integrated component rather than separate assemblies.
4Object-affected harmful factors
If multiple LEDs with different wavelengths are used to eliminate blue light, then harmful wavelengths are reduced, but the device complexity and manufacturing cost increase
Solution Approach 1:
Instead of using multiple LEDs, the patent uses a single LED with a down-converting element as an intermediary to achieve multi-wavelength output. The down-converting element converts part of the blue light to other wavelengths, effectively creating a multi-spectral light source from a single LED, thereby reducing device complexity.
Solution Approach 2:
The down-converting element provides multi-functionality by simultaneously reducing harmful blue light and generating useful illumination at other wavelengths. This single component performs multiple functions that would otherwise require multiple LEDs, simplifying the device structure and reducing manufacturing complexity.
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 combination of a planarization layer and optical coating enhances light extraction and reduces temperature, allowing PIS-type light converters to perform better and overcome issues associated with other types of light converters.
Implementation Method 1
The down-converting element may be in the form of a phosphor material, a fluorescent material, or any other material that absorbs light at a first wavelength and emits light at a second wavelength
Implementation Method 2
The light guide may be configured to receive light from the LED and distribute the light across a display screen
Data Source
Figure 1
Figure 2b
Figure 3
AI summary
A light converter and method of manufacture is provided. A light conversion layer (301), comprising light conversion particles (301a) in a binding material (301b) is provided for generating emission light from excitation light incident on the light conversion layer (301). A planarization layer (304) is on a surface of the light conversion layer (301) and at least one optical coating (305) is part of or on a surface of the planarization layer (304) that is relatively smooth in comparison with the surface of the light conversion layer (301).