OLED Display Node Voltage Compensation for Low-Speed Driving
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In low-speed driving modes of organic light-emitting diode display devices, the node voltage of each pixel changes during the image holding period, leading to current leakage and image deterioration, which undermines the effectiveness of power consumption reduction strategies.
Innovation Solution
A display device and driving method that compensates the node voltage of each pixel using reference compensation voltages set by an optical compensation inspection circuit, applying different voltages at the start and end times of the image holding period to maintain image data voltage stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If low-speed driving mode is used to reduce power consumption, then power consumption is reduced, but image quality deteriorates due to current leakage and voltage changes during the extended holding period
Solution Approach 1:
The patent applies preliminary action by setting reference compensation voltages before the image holding period begins. The optical compensation inspection circuit measures brightness and luminance characteristics in advance, then sets appropriate reference compensation voltages to compensate for node voltage changes that will occur during the extended holding period in low-speed driving mode, preventing image quality deterioration before it happens.
Solution Approach 2:
The patent implements feedback by using an optical compensation inspection circuit to measure brightness and luminance characteristic variations of the displayed image. Based on these measurements, the system adjusts and sets reference compensation voltages to maintain stable node voltages during the image holding period, creating a closed-loop control system that ensures image quality while operating in low-speed driving mode.
2Use of energy by stationary object
If image holding period is extended in low-speed driving mode, then power consumption is reduced, but node voltage changes causing current leakage occur
Solution Approach 1:
The system performs preliminary measurement of brightness and luminance characteristics using the optical compensation inspection circuit before the image holding period. Based on these measurements, reference compensation voltages are set in advance to counteract the node voltage changes that would otherwise cause current leakage during the extended holding period in low-speed driving mode.
Solution Approach 2:
The patent changes the voltage parameter by introducing reference compensation voltages that are set based on measured brightness and luminance characteristics. These compensation voltages are applied to counteract node voltage changes during the image holding period, preventing current leakage while maintaining the extended holding period necessary for low-speed driving mode operation.
3Reliability
If reference compensation voltages are set and applied at start and end times of image holding period, then image quality is maintained, but device complexity increases
Solution Approach 1:
The patent achieves multi-functionality by using the optical compensation inspection circuit to perform both image quality measurement and reference compensation voltage setting. The data driver is designed to handle both normal image data writing and reference compensation voltage application, reducing the need for separate dedicated circuits and minimizing overall device complexity while maintaining image quality.
Data Source
AI summary
Disclosed are a display device and a driving method thereof. A reference compensation voltage for compensating for a node voltage of each pixel for an image holding period after a refresh period for which image data is input in a low-speed driving mode is set. Then, the node voltage of each sub-pixel is compensated for using a corresponding reference compensation voltage on at least one frame basis at each start time and each end time of the image holding period, thereby preventing low image quality and reducing power consumption.