Pixel Circuit Anode Initialization for Reduced Display Afterimages
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in effectively initializing the anode of light emitting elements, leading to afterimages due to insufficient initialization periods.
Innovation Solution
A pixel circuit design that includes a light emitting element, a write transistor, a driving transistor, a compensation transistor, a first initialization transistor, and a second initialization transistor, with a bias gate signal having an activation period longer than other signals to initialize the anode electrode of the light emitting element for an extended duration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the initialization period is extended to reduce afterimages, then display quality is improved, but the pixel circuit complexity increases
Solution Approach 1:
The initialization process is segmented into two distinct phases: a first initialization period for initializing the control electrode of the driving transistor, and a second initialization period for initializing the anode electrode. This segmentation allows each initialization task to be performed independently with appropriate timing and transistor control, achieving thorough initialization without requiring a single overly complex initialization circuit.
Solution Approach 2:
The pixel circuit performs preliminary initialization actions before the light emitting element activates. The first initialization transistor initializes the control electrode in advance, and the second initialization transistor initializes the anode electrode in advance, ensuring that both electrodes are properly prepared before operation begins, thereby preventing afterimages.
2Reliability
If the bias gate signal activation period is increased to initialize the anode electrode thoroughly, then afterimages are reduced, but the time for other operations decreases
Solution Approach 1:
The pixel circuit employs periodic action by dividing the initialization process into two distinct periods: a first initialization period during which the first initialization transistor operates to initialize the control electrode, and a second initialization period during which the second initialization transistor operates to initialize the anode electrode. This periodic structure ensures that each initialization task receives adequate time while the total operation time is optimized through non-overlapping execution.
Solution Approach 2:
The control electrode is initialized in advance during the first initialization period before the second initialization period begins. This preliminary action ensures that the driving transistor is properly prepared before the anode electrode initialization, allowing both tasks to be completed thoroughly without interfering with each other.
Data Source
AI summary
A pixel circuit includes a light emitting element, a write transistor configured to write a data voltage in response to a write gate signal, a driving transistor configured to generate a driving current based on the data voltage and to apply the driving current to the light emitting element, a compensation transistor configured to diode-connect the driving transistor in response to a compensation gate signal, a first initialization transistor configured to apply a first initialization voltage to a control electrode of the driving transistor in response to an initialization gate signal, and a second initialization transistor configured to apply a second initialization voltage to an anode electrode of the light emitting element in response to a bias gate signal having an activation period longer than at least one of the compensation gate signal and the initialization gate signal.