LED Sealing Units with Graded Phosphor Concentration

Solution Overview

Problem

Light-emitting devices with LEDs exhibit variations in color shades due to viewing angles, primarily caused by manufacturing methods and structures, resulting in a narrow light distribution angle and inconsistent color emission.

Innovation Solution

A light-emitting device design featuring a first sealing unit with a light-transmissive resin and phosphors at a specific concentration, covered by a second sealing unit with a higher phosphor concentration, where the phosphors in both units fluoresce to produce light with the same wavelength, and the boundary surface between them is pear-grounded to enhance light distribution and color mixing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a single sealing unit with uniform phosphor concentration is used, then the manufacturing process is simple, but the light distribution angle is narrow and color shade varies with viewing angle

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidlight distribution angle

Core Design Contradiction:

Ease of manufactureVSIllumination intensity

Solution Approach 1:

The sealing unit is divided into multiple sealing units with different phosphor concentrations. The first sealing unit has a first phosphor concentration and the second sealing unit has a second phosphor concentration higher than the first. This segmentation allows different regions to contribute differently to light emission, widening the light distribution angle while maintaining manufacturing feasibility through modular assembly.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the sealing structure are assigned different phosphor concentrations tailored to their specific functions. The first sealing unit with lower phosphor concentration provides base illumination, while the second sealing unit with higher phosphor concentration enhances light distribution in specific directions. This local differentiation resolves the contradiction by optimizing each region's contribution to overall light performance.

Inventive Principle:

Principle #3Local quality

2Device complexity

If a single sealing unit with uniform phosphor concentration is used, then the device structure is simple, but the color shade varies with viewing angle

Engineering Contradiction:

Improvesealing unit structureVSAvoidcolor consistency

Core Design Contradiction:

Device complexityVSStability of the object's composition

Solution Approach 1:

The sealing unit is divided into multiple sealing units with different phosphor concentrations. The first sealing unit has a first phosphor concentration and the second sealing unit has a second phosphor concentration higher than the first. This segmentation allows different regions to contribute differently to light emission, widening the light distribution angle while maintaining manufacturing feasibility through modular assembly.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the sealing structure are assigned different phosphor concentrations tailored to their specific functions. The first sealing unit with lower phosphor concentration provides base illumination, while the second sealing unit with higher phosphor concentration enhances light distribution in specific directions. This local differentiation resolves the contradiction by optimizing each region's contribution to overall light performance.

Inventive Principle:

Principle #3Local quality

3Illumination intensity

If multiple sealing units with different phosphor concentrations are used, then the light distribution angle is widened and color consistency is improved, but the manufacturing process becomes more complex

Engineering Contradiction:

Improvelight distribution angleVSAvoidmanufacturing complexity

Core Design Contradiction:

Illumination intensityVSEase of manufacture

Solution Approach 1:

The sealing unit is divided into multiple sealing units with different phosphor concentrations. The first sealing unit has a first phosphor concentration and the second sealing unit has a second phosphor concentration higher than the first. This segmentation allows different regions to contribute differently to light emission, widening the light distribution angle while maintaining manufacturing feasibility through modular assembly.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the sealing structure are assigned different phosphor concentrations tailored to their specific functions. The first sealing unit with lower phosphor concentration provides base illumination, while the second sealing unit with higher phosphor concentration enhances light distribution in specific directions. This local differentiation resolves the contradiction by optimizing each region's contribution to overall light performance.

Inventive Principle:

Principle #3Local quality

4Stability of the object's composition

If multiple sealing units with different phosphor concentrations are used, then the color consistency is improved, but the device structure becomes more complex

Engineering Contradiction:

Improvecolor consistencyVSAvoidsealing unit structure

Core Design Contradiction:

Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The sealing unit is divided into multiple sealing units with different phosphor concentrations. The first sealing unit has a first phosphor concentration and the second sealing unit has a second phosphor concentration higher than the first. This segmentation allows different regions to contribute differently to light emission, widening the light distribution angle while maintaining manufacturing feasibility through modular assembly.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the sealing structure are assigned different phosphor concentrations tailored to their specific functions. The first sealing unit with lower phosphor concentration provides base illumination, while the second sealing unit with higher phosphor concentration enhances light distribution in specific directions. This local differentiation resolves the contradiction by optimizing each region's contribution to overall light performance.

Inventive Principle:

Principle #3Local quality

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 design widens the light distribution angle and reduces color shade variation across different emission angles, achieving consistent color output and improved lighting efficiency by controlling the interaction of light at the boundary surface.

Implementation Method 1

the phosphors in both units fluoresce to produce light with the same wavelength

Methodology Applied

Scientific EffectFluorescence: Fluorescence

Data Source

PatentUS9117980B2Light-emitting device including sealing units with different phosphor concentrations

Publication Date: 2015.08.25 SEOUL SEMICONDUCTOR

AI summary

A light-emitting device includes a light-emitting element, a first sealing unit that covers the light-emitting element and includes a light-transmissive resin, and a second sealing unit disposed on top of the first sealing unit and includes a light-transmissive resin. The light-transmissive resin of the first and second sealing units contain phosphor of the same type but at different levels of concentration.