LED Filament Parallel Branch Layout for Uniform Light and Low Flicker
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LED filaments face challenges such as uneven light distribution, stress concentration leading to metal wiring fractures, difficulty in bending, uneven color temperature, and high cost due to the use of graphene, as well as issues with flicker and increased circuit complexity.
Innovation Solution
The LED filament design includes parallel current branches with different color temperatures, a flexible structure with a base layer and electrodes, and a covering layer with temperature-sensitive materials, along with a driving circuit to reduce stress and improve light uniformity and efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single current branch with uniform LED chips is used, then the circuit is simple, but the light distribution is uneven and color temperature is inconsistent
Solution Approach 1:
The patent divides the LED filament into multiple current branches, each containing LED chips with different color temperatures (e.g., warm white and cool white LEDs). This segmentation allows different sections to emit different colors of light, which when combined, create a more uniform overall light distribution and consistent color temperature across the entire filament.
2Stability of the object's composition
If a rigid substrate is used to support LED chips, then the structure is stable, but the filament cannot be bent and stress concentrates leading to metal wiring fractures
Solution Approach 1:
The patent replaces rigid substrates with flexible substrates that can be bent without causing stress concentration. The flexible substrate maintains structural stability to support LED chips and metal wiring while allowing the filament to be bent into different shapes, preventing wiring fractures and enabling versatile installation configurations.
3Quantity of substance
If graphene is used for cost reduction, then the material cost decreases, but the manufacturing process becomes more complex and quality control is more difficult
Solution Approach 1:
The patent replaces expensive materials like graphene with more cost-effective alternative materials that achieve similar functional performance. These alternative materials are easier to manufacture with standard processes, simplify production, and improve quality control while maintaining the required electrical and thermal properties for LED filament operation.
4Illumination intensity
If high power is used to increase brightness, then the illumination intensity improves, but flicker increases and energy efficiency decreases
Solution Approach 1:
The patent employs periodic action through pulse-width modulation (PWM) dimming control and alternating activation of different color temperature branches. This periodic control maintains high brightness when needed while allowing energy-saving modes during normal operation, reducing overall energy consumption and minimizing flicker effects through controlled switching patterns that synchronize with human visual perception.
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 uniform light distribution, reduces stress on metal wiring, lowers cost by avoiding graphene, and minimizes flicker, while maintaining consistent color temperature and reducing circuit complexity.
Implementation Method 1
a covering layer with temperature-sensitive materials
Implementation Method 2
a plurality of first LED chips and at least one current-limiting resistor are disposed on the base layer and connects in series to form a first current branch
Data Source
AI summary
An LED filament including a base layer, two electrodes, a plurality of first LED chips and at least one current-limiting resistor connects in series to form a first current branch, a plurality of second LED chips connects in series to form a second current branch, and a covering layer covers the plurality of first LED chips, the at least one current-limiting resistor, the plurality of second LED chips and a part of each two electrodes. Two ends of the first current branch are connected to the two electrodes respectively, two ends of the second current branch are connected to the two electrodes respectively, the first current branch is connected in parallel with the second current branch.