Display Pixel Repair Circuit for Reduced Brightness Difference
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Defective pixels in display apparatuses often emit constant light or appear as dark spots, complicating repair processes as circuits become more complex, leading to reduced display quality.
Innovation Solution
A display apparatus with a substrate featuring an active area and a dummy area, incorporating a repair line connected to a dummy circuit, a pixel connection electrode, and a voltage transfer line, which overlaps the repair line but is spaced apart, allowing for the repair of defective pixels by connecting them to dummy circuits to maintain normal operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a repair line is connected to a pixel electrode to repair a defective pixel, then the defective pixel can be restored to normal operation, but a parasitic capacitor is formed between the repair line and the pixel electrode causing brightness differences and reduced display quality
Solution Approach 1:
The patent extracts the harmful parasitic capacitance effect by separating the voltage transfer function from the pixel connection function. The voltage transfer line is spaced apart from the pixel connection electrode, removing the harmful electrical coupling while preserving the necessary voltage transfer to the pixel electrode through the repair line.
Solution Approach 2:
The patent introduces a voltage transfer line as an intermediary element that mediates between the power supply and the pixel electrode. This intermediary allows voltage transfer without direct contact between the repair line and pixel electrode, thereby eliminating the parasitic capacitor formation while still achieving the repair objective.
2Adaptability or versatility
If the pixel circuit structure becomes more complex to improve display functionality, then display features are enhanced, but the difficulty of repairing defective pixels increases
Solution Approach 1:
The patent segments the pixel structure by separating the pixel electrode connection (through pixel connection electrode) from the voltage transfer path (through voltage transfer line). This segmentation allows independent optimization: the pixel circuit can become more complex for enhanced functionality while the repair mechanism remains simple through the dedicated repair line connected to the dummy circuit.
Solution Approach 2:
The repair line serves multiple functions: it connects defective pixels to dummy circuits for repair, transfers voltage to pixel electrodes, and works with both active and dummy circuits. This multi-functionality allows complex display features while maintaining a unified, simple repair approach across all pixel types.
3Ease of repair
If a dummy area is added to the substrate to accommodate dummy circuits for pixel repair, then pixel repair capability is improved, but the substrate area increases
Solution Approach 1:
The patent utilizes the dummy area located at the periphery of the active display area, effectively using the boundary region in another spatial dimension. This allows the dummy circuits to be positioned without encroaching on the active pixel area, achieving repair capability while minimizing impact on display area.
Solution Approach 2:
The dummy circuits are simplified copies of the actual pixel circuits, containing only the essential components needed for voltage transfer and repair operations. This copying approach provides the necessary repair functionality without duplicating the full complexity of active pixel circuits, thereby reducing the area requirement for the dummy region.
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 improves display quality by reducing brightness differences and enabling defective pixels to function normally, enhancing the overall performance of the display apparatus.
Implementation Method 1
reducing a brightness difference depending on a voltage by reducing a coupling effect of a parasitic capacitor formed between a repair line used in a repair process and a pixel electrode
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A display apparatus that may include a substrate that may include an active area and a dummy area, a pixel circuit in the active area and a light-emitting element electrically connected to the pixel circuit and including a pixel electrode, a dummy circuit in the dummy area, a repair line extending in a first direction over the substrate, electrically connected to the dummy circuit, and is connectable to the light-emitting element, a pixel connection electrode overlapping the repair line and electrically connected to the pixel electrode, and a voltage transfer line overlapping the repair line, spaced apart from the pixel connection electrode, and configured to transfer a voltage to the pixel circuit, wherein an area of a portion of the voltage transfer line overlapping the repair line may be greater than an area of a portion of the pixel connection electrode overlapping the repair line.