EL Display Panel Driving with Reverse Bias Aging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic electro-luminescence (EL) display devices face a short lifespan and line defects due to stress, despite aging processes during manufacturing, as their performance degrades over time and is prone to defects during driving.
Innovation Solution
A method and apparatus for driving an electro-luminescence display panel that includes alternating between scan and aging periods, applying reverse bias voltages, and generating voltage differences between scan lines to perform self-aging, thereby extending the panel's lifespan and preventing defects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If aging process is performed during manufacturing, then initial stability is improved, but lifespan is shortened due to stress-induced defects during driving
Solution Approach 1:
The patent applies preliminary action by performing an aging process during manufacturing before the display device is put into service. This preliminary aging stabilizes the organic electroluminescence material by allowing it to undergo initial degradation and stabilization under controlled conditions, thereby improving long-term reliability and reducing defects during actual operation.
2Illumination intensity
If forward voltage is applied continuously for light emission, then brightness is maintained, but stress accumulates causing line defects and reduced lifespan
Solution Approach 1:
The patent implements periodic action by alternating between forward voltage application (for light emission) and reverse voltage application (for stress relief and aging). This periodic switching between operational and maintenance modes allows the display to maintain brightness while periodically reducing accumulated stress in the organic electroluminescence material, thereby preventing line defects and extending lifespan.
Solution Approach 2:
The patent applies preliminary anti-action by using reverse voltage to counteract the stress accumulated during forward voltage operation. The reverse voltage creates an opposing electrical stress that neutralizes degradation effects, preventing the formation of line defects and maintaining reliability during continuous operation.
3Duration of action of stationary object
If reverse bias is applied for aging during driving, then lifespan is extended, but operational time is reduced
Solution Approach 1:
The patent resolves this contradiction through periodic action by integrating aging periods into the operational cycle. Instead of separating aging and operation into distinct time periods, the system periodically switches between forward and reverse voltage modes during operation, allowing both light emission and stress relief to occur within the same operational timeframe.
Solution Approach 2:
The patent merges the aging function with the operational function by combining forward voltage (light emission) and reverse voltage (stress relief) cycles into a single integrated operation mode. This merging allows the display to simultaneously achieve both operational performance and longevity enhancement without sacrificing operational time.
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 proposed method and apparatus effectively extend the lifespan of the EL display panel by maintaining a reverse bias state during operation, reducing stress-induced defects and improving aging efficiency.
Implementation Method 1
The EL display panel is a self-luminous device capable of light-emitting a phosphorous material by a re-combination of electrons with holes
Data Source
AI summary
The present invention relates to a method and apparatus for driving an electro-luminescence display panel capable of doing an aging operation upon driving.A method of driving an electro-luminescence display panel according to the present invention includes: a scan period when electro-luminescence cells formed at a cross of both a plurality of scan lines and a plurality of data lines are line-sequentially emitted; and an aging period when an aging is performed in the electro-luminescence cells at the same time by applying a reverse bias, wherein the scan period and the aging period are repeated for each frame.