LED Light Transmitting Layer Structure for Graininess-Free Illumination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing light emitting devices suffer from graininess when viewed from a distance due to the arrangement of light emitting elements, and increasing the diffusion degree of a diffusion plate to address this issue reduces luminous efficiency and increases the size of the light fixture.
Innovation Solution
A light emitting device is designed with a substrate, first light emitting elements with a first LED die, a first light transmitting layer, a second light transmitting layer, and a reflector with an upwardly bulging curved surface. The thickness between the LED dies and the first light transmitting layer is greater than a calculated minimum, and the horizontal distance between contact points on the reflector is greater than the distance between contact points on the light transmitting layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the distance between the light emitting devices and the diffusion plate is increased, then the brightness uniformity is improved, but the size of the light fixture is increased
Solution Approach 1:
The patent transitions from a single-layer diffusion plate to a multi-layer light transmitting structure with varying thicknesses. The first light transmitting layer has a greater thickness than the second light transmitting layer, creating a gradient structure that achieves uniform brightness distribution without increasing the overall distance or fixture size. This dimensional variation in layer thickness allows light to diffuse uniformly while maintaining a compact fixture form factor.
2Illumination intensity
If the diffusion degree of the diffusion plate is increased, then the brightness uniformity is improved, but the luminous efficiency is reduced
Solution Approach 1:
The patent applies different diffusion characteristics to different regions and layers. The first light transmitting layer has a greater thickness and provides stronger diffusion, while the second light transmitting layer has a smaller thickness and provides weaker diffusion. This local differentiation allows each layer to contribute optimally to brightness uniformity while minimizing overall energy loss, achieving a balance between diffusion effectiveness and luminous efficiency.
3Illumination intensity
If a diffusion plate is arranged between the light emitting devices and the observer, then the graininess is reduced, but the brightness uniformity improvement requires larger distance or higher diffusion degree
Solution Approach 1:
The patent divides the diffusion function into multiple discrete layers instead of using a single diffusion plate. The light transmitting structure is segmented into a first light transmitting layer and a second light transmitting layer, each with different thicknesses. This segmentation allows the diffusion function to be distributed across multiple interfaces, achieving effective graininess reduction and brightness uniformity without requiring a large single diffusion element that would increase fixture size.
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 solution achieves more uniform brightness in the emitted light, preventing graininess while maintaining efficient luminous performance and reducing the size of the light fixture.
Implementation Method 1
a reflector having an upwardly bulging curved surface at an upper portion of an inner wall that the first light transmitting layer and the second light transmitting layer contact, the reflector being arranged on the substrate so as to surround the plurality of first light emitting elements and reflecting light emitted from the first light emitting elements
Data Source
AI summary
A light emitting device has a substrate, a plurality of first light emitting elements, each of which is mounted on the substrate, has a first LED die, and emits light having a first wavelength, a first light transmitting layer arranged so as to cover the plurality of first light emitting elements, the first light transmitting layer transmitting light emitted from the plurality of first light emitting elements, a second light transmitting layer arranged so as to cover the first light transmitting layer, the second light transmitting layer transmitting light that has transmitted through the first light transmitting layer, and a reflector having an upwardly bulging curved surface at an upper portion of an inner wall that the first light transmitting layer and the second light transmitting layer contact, the reflector being arranged on the substrate so as to surround the plurality of first light emitting elements and reflecting light emitted from the first light emitting elements, wherein the thickness T between the upper surfaces of the first LED dies and the upper surface of the first light transmitting layer is greater than a thickness T1 defined asT1=LG1/(2tanθc)wherein LG1 is the distance between the first LED dies, and θc is a critical angle for the case where light is emitted from the first light transmitting layer to air, and the horizontal distance between a second contact part, where the top of the second light transmitting layer contacts the curved surface of the reflector, and the bottom of the inner wall of the reflector is greater than the horizontal distance between a first contact part, where the top of the first light transmitting layer contacts the reflector, and the bottom of the inner wall of the reflector.