Planar Light Source Device Thermal Management via LED Spacing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing planar light source devices face challenges in heat dissipation and light-emitting efficiency due to the distance between light-emitting diode chips and the thickness of the substrate, which are not adequately addressed in previous designs.
Innovation Solution
A planar light source device with light-emitting diode chips of specific size (0.0784 mm2 to 0.25 mm2) spaced at least twice their length apart, and a substrate thickness of 1.0 mm or more, incorporating a metal layer and a reflective cover layer with inner holes to enhance heat dissipation and light emission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the distance between adjacent light-emitting diode chips is reduced to increase light emission density, then light emission efficiency is improved, but heat dissipation deteriorates
Solution Approach 1:
The patent applies local quality by creating distinct thermal zones through strategic spacing of LED chips. Each chip is positioned with sufficient clearance (at least twice the chip length) to establish independent heat dissipation zones, allowing local thermal management while maintaining overall high light emission density across the substrate surface.
Solution Approach 2:
The patent changes the spatial parameter of chip spacing to optimize both light emission and heat dissipation. By setting the distance between adjacent chips to at least twice the chip length, the patent transforms the density parameter to achieve a balance where sufficient light emission is maintained while thermal interference between chips is minimized.
2Temperature
If the substrate thickness is increased to improve heat dissipation, then heat dissipation is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent optimizes the substrate thickness parameter to achieve effective heat dissipation without excessive complexity. By specifying a minimum thickness of 1.0 mm, the patent ensures sufficient thermal conduction path length while avoiding the diminishing returns and increased manufacturing complexity associated with much thicker substrates.
Solution Approach 2:
The patent employs a composite substrate structure combining a metal layer (for thermal conduction) with an insulating layer. This composite approach enables effective heat dissipation through the metal component while the insulating layer provides electrical isolation and structural support, achieving thermal performance without proportionally increasing device complexity.
3Illumination intensity
If the chip size is reduced to increase chip density, then light emission density is improved, but heat dissipation per unit area deteriorates
Solution Approach 1:
The patent applies local quality by ensuring each small LED chip has sufficient surrounding space (distance of at least twice the chip length from adjacent chips). This local clearance creates adequate thermal diffusion area for each chip, allowing small chips to maintain effective heat dissipation while achieving high overall light emission density through increased chip count.
Solution Approach 2:
The patent segments the substrate into multiple small LED chip units, each with its own thermal management zone. By dividing the light emission function into numerous small segments rather than using fewer large chips, the patent achieves high light emission density while each segment maintains adequate heat dissipation capability through the prescribed spacing.
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 maintains low chip temperatures, optimizing heat dissipation and light-emitting efficiency while balancing manufacturing costs and assembly complexity.
Implementation Method 1
Each of the light-emitting diode chips has a chip size defined by length×width of the chip and ranging from 0.0784 mm2 to 0.25 mm2. Two adjacent ones of the light-emitting diode chips are spaced apart from each other by a distance of at least two times a length of the light-emitting diode chips.
Implementation Method 2
A planar light source device with light-emitting diode chips of specific size (0.0784 mm2 to 0.25 mm2) spaced at least twice their length apart, and a substrate thickness of 1.0 mm or more, incorporating a metal layer and a reflective cover layer with inner holes to enhance heat dissipation and light emission.
Data Source
AI summary
A planar light source device includes: a substrate having a thickness larger than 0.9 mm and including a metal layer; and a plurality of light-emitting diode chips disposed on the substrate in a matrix array. Each light-emitting diode chip has a chip size ranging from 0.0784 mm2 to 0.25 mm2. Two adjacent ones of the light-emitting diode chips are spaced apart from each other by a distance of at least two times a length of the light-emitting diode chips.