Textured Substrate Wavelength Conversion Light Collimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wavelength converted light emitting devices do not effectively collimate light extracted from the wavelength converting structure, leading to inefficient light distribution and directional emission.
Innovation Solution
A textured substrate is positioned in the path of light extracted from the wavelength converting structure, featuring a dielectric layer with a textured top surface and a body, enhancing light collimation by creating a refractive index contrast that directs light emission in specific directions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a planar substrate is used in wavelength converted light emitting devices, then the device structure is simple and easy to manufacture, but light extraction is inefficient and light distribution is poor
Solution Approach 1:
The substrate surface is textured with curved features such as domes, hemispheres, or spherical protrusions instead of a flat planar surface. This curvature increases the optical path length of extracted light, enhances light scattering, and improves light extraction efficiency from the wavelength converting structure while maintaining manufacturing feasibility through techniques like reflow processing or embossing.
Solution Approach 2:
The substrate surface morphology is changed from planar to textured by modifying physical parameters such as surface roughness, feature height, and feature density. These parameter changes create refractive index variations that enhance light extraction and collimation without fundamentally changing the substrate material or device architecture.
2Device complexity
If light is extracted directly from the wavelength converting structure without collimation, then the device structure is simple, but light distribution is inefficient and directional emission is poor
Solution Approach 1:
The curved or domed surface features on the substrate act as micro-lenses that naturally collimate extracted light. The spherical geometry focuses light rays into more directional beams, improving illumination intensity and light distribution efficiency without requiring additional complex optical components such as external lenses or reflectors.
3Illumination intensity
If a textured substrate with dielectric layer is implemented, then light collimation is significantly improved, but device complexity and manufacturing difficulty increase
Solution Approach 1:
The textured substrate with dielectric layer serves multiple functions simultaneously: it acts as a structural support, a light extraction enhancement element, a collimation feature, and a protective layer. The dielectric material fills the textured features and provides both mechanical stability and optical functionality, eliminating the need for separate components and reducing overall device complexity despite the added texturing process.
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 textured substrate significantly improves light collimation, resulting in more focused and directional emission, as illustrated by the increased far-field intensity in specific planes, enhancing the luminance and light distribution of the device.
Implementation Method 1
The wavelength converting structure is disposed between the substrate and the flip chip semiconductor light emitting device
Data Source
AI summary
Embodiments of the invention include a flip chip semiconductor light emitting device and a wavelength converting structure disposed in a path of light extracted from the flip chip semiconductor light emitting device. A substrate with a textured top surface is positioned with the bottom surface facing the wavelength converting structure. The wavelength converting structure is disposed between the substrate and the flip chip semiconductor light emitting device.