LED Package with Phosphor Cap and Thermal Buffer Layer
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LED packages face challenges in achieving uniform color, high luminance, and wide view angle due to poor adhesive force between phosphor films and LEDs, leading to increased color deviation and reduced reliability, especially when applied to horizontal type LEDs.
Innovation Solution
A phosphor layer is formed as a cap surrounding the sides and top of the LED with a uniform thickness, and a buffer layer is applied between the LED and the phosphor layer to suppress heat and prevent detachment, using materials like transparent silicon, epoxy, or glass resin.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a phosphor film is attached to an LED using electrostatic force or adhesive force, then the phosphor film can be applied to the LED surface, but the adhesive force is insufficient leading to poor reliability and color deviation
Solution Approach 1:
A buffer layer made of transparent resin is introduced as an intermediary between the LED and the phosphor layer. This buffer layer provides sufficient adhesive force to securely attach the phosphor layer to the LED surface, preventing detachment while maintaining color uniformity and reducing color deviation.
Solution Approach 2:
The patent uses a composite structure combining the LED, transparent resin buffer layer, and phosphor layer. This multi-material composite approach ensures strong adhesion through the resin buffer while maintaining optical properties for color uniformity.
2Adaptability or versatility
If the phosphor film is applied to horizontal type LEDs, then the LED structure can be utilized, but the phosphor film detaches due to insufficient adhesive force
Solution Approach 1:
The transparent resin buffer layer serves as a mediator that provides strong adhesive bonding between the phosphor layer and the LED surface, enabling reliable attachment on horizontal type LEDs where gravitational and thermal stresses would otherwise cause detachment.
3Illumination intensity
If the phosphor layer is disposed to surround sides and top of LED with uniform thickness, then luminance and view angle are improved, but manufacturing complexity increases
Solution Approach 1:
The phosphor layer is extended from a simple top surface application to a three-dimensional cap structure that surrounds both the sides and top of the LED. This dimensional extension ensures uniform phosphor distribution across all light-emitting surfaces, achieving consistent color and improved luminance from multiple viewing angles.
Solution Approach 2:
The buffer layer is applied in advance to the LED surface before the phosphor layer is formed. This preliminary action of coating the buffer layer facilitates the subsequent formation of the uniform phosphor cap structure and ensures proper adhesion throughout the manufacturing process.
4Manufacturing precision
If the phosphor layer is disposed close to the LED top, then color uniformity is improved, but the phosphor layer is deteriorated by heat from the LED
Solution Approach 1:
The transparent resin buffer layer acts as a thermal intermediary between the heat-generating LED and the phosphor layer. It provides thermal insulation to protect the phosphor layer from heat-induced deterioration while maintaining close proximity for optimal color uniformity and light extraction.
Solution Approach 2:
The buffer layer is implemented as a thin film structure that provides both thermal protection and mechanical support. This thin film approach maintains close spacing for color uniformity while the resin material provides sufficient thermal insulation to prevent phosphor deterioration.
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 luminance, view angle, and color uniformity while protecting the phosphor layer from heat-induced deterioration, improving manufacturing efficiency and yield.
Implementation Method 1
a buffer layer disposed between the top of the LED and a bottom of the phosphor layer and configured to suppress heat, generated from the top of the LED, from being transferred to the bottom of the phosphor layer
Implementation Method 2
a phosphor layer formed as a cap, disposed to surround the sides and top of the LED
Data Source
AI summary
Disclosed herein is a light-emitting diode (LED) package in accordance with an embodiment of the present invention, which includes an LED configured to provide light of a wavelength having a specific region, a circuit board electrically connected to the LED through bonding pads formed at the bottom of the LED, a phosphor layer formed as a cap, disposed to surround sides and a top of the LED, and configured to have sides and top thereof formed to a uniform thickness, and a buffer layer disposed between the top of the LED and a bottom of the phosphor layer and configured to suppress heat, generated from the top of the LED, from being transferred to the bottom of the phosphor layer and to prevent a bottom of the phosphor layer from being deviated from the top of the LED.