Flexible LED Filament with Bent Conductive Paths for Uniform Lighting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
LED light bulbs with LED filaments face challenges in achieving uniform illumination due to the inflexibility of hard filaments, which are prone to stress concentration and substrate blockage, and soft filaments suffer from thermal expansion issues and metal wire bonding problems, leading to instability and complex assembly processes.
Innovation Solution
The design incorporates a flexible LED filament with a conductive portion that includes a series of LED chips connected by a conductive electrode, featuring a light conversion layer and solder layers for improved bendability and stability, reducing stress concentration and enhancing illumination uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If LED hard filament with glass substrate is used, then structural stability is improved, but illumination uniformity deteriorates due to substrate blockage and point light source effect
Solution Approach 1:
The patent removes the traditional glass substrate from the LED filament structure. LED chips are directly mounted on a support wire without a substrate, eliminating the substrate's light-blocking effect and point light source problem while maintaining structural stability through the support wire design
Solution Approach 2:
The patent employs a thin support wire structure instead of a rigid glass substrate. This thin-film approach allows light to pass through more effectively and enables the filament to be bent into various shapes for improved illumination distribution while maintaining structural integrity
2Adaptability or versatility
If LED soft filament with FPC substrate is used, then bendability is improved, but reliability deteriorates due to thermal expansion mismatch and metal wire bonding damage
Solution Approach 1:
The patent removes the FPC substrate from the LED filament structure. LED chips are directly mounted on a support wire without FPC, eliminating the thermal expansion mismatch problem between FPC and silicon gel coating that caused chip displacement and degumming
Solution Approach 2:
The patent applies a protective coating to the support wire before mounting LED chips. This preliminary protective layer prevents metal wire bonding damage during bending while maintaining the flexibility needed for shape adjustment
3Illumination intensity
If multiple LED filaments are combined to achieve uniform illumination, then illumination uniformity is improved, but device complexity increases
Solution Approach 1:
The patent divides a single LED filament into multiple segments with LED chips arranged at different positions along the support wire. Each segment can be independently positioned to achieve uniform illumination distribution, eliminating the need for multiple separate filaments and simplifying assembly
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 provides a flexible LED filament that achieves omni-directional lighting with reduced stress on metal wires, improved heat dissipation, and simplified assembly, resulting in a more uniform and efficient lighting effect.
Implementation Method 1
at least a portion of the light emitted by the LED chip is converted to a different wavelength by a light conversion layer
Data Source
AI summary
An LED light filament includes an LED section, first and second conductive electrodes, and a conductive portion. The LED section includes LED chips. The first conductive electrode and the second conductive electrode are disposed at two ends of the LED section. The conductive portion is electrically connected between the LED chips. An LED chip among the LED chips has an electrical connecting portion, an end portion of the conductive portion is connected to the electrical connecting portion, the conductive portion has a first bent portion and a second bent portion. The conductive portion extends from the electrical connecting portion along a first direction of the LED chip, toward a second direction of the LED chip through the first bent portion, and toward a third direction of the LED chip through the second bent portion, and the first to third directions are different directions. An LED light bulb is also provided.