Display Driver Polarity Inversion for DC Voltage Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices face issues with image sticking and smears due to DC voltage accumulation, and high power consumption, particularly when performing additional functions like touch sensing and fingerprint recognition, which can degrade image quality and increase power usage.
Innovation Solution
A display device with a data driver that inverts the polarity of data voltage in each frame and operates at a low frequency, reducing power consumption by cutting off power during non-output periods and dividing the display area into regions driven at different frequencies to manage scan signal output.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the gate driver is driven at a high frequency to satisfy temporary driving conditions, then the response speed is improved, but the power consumption increases
Solution Approach 1:
The gate driver operates in two distinct modes: a first mode for normal operation and a second mode for low-power operation. The system dynamically switches between these modes based on driving speed control signals, allowing the gate driver to adjust its operating frequency and power consumption levels adaptively rather than maintaining a fixed high-frequency operation
Solution Approach 2:
The invention changes the operating parameters of the gate driver by adjusting the frequency at which scan signals are output. In the second mode, the gate driver outputs scan signals at a slower frequency (lower parameter value) compared to the first mode, thereby reducing power consumption while still maintaining functional operation
2Ease of operation
If the gate driver outputs scan signals at constant frequency from all stages, then the operation is simplified, but additional functions like touch sensing and fingerprint recognition cannot be performed
Solution Approach 1:
The gate driver operation is segmented into two distinct modes with different characteristics. The first mode maintains simple constant-frequency operation for basic display functions, while the second mode enables additional functions by operating at slower frequencies. This segmentation allows the system to optimize for either simplicity or versatility depending on the operational requirements
Solution Approach 2:
The gate driver periodically switches between two operating modes based on control signals. During periods when additional functions are needed, the system transitions to the second mode with slower scan signal output, creating periodic intervals where touch sensing and fingerprint recognition can be performed without interfering with the main display operation
3Loss of time
If the period where an image is displayed in each frame period is reduced to secure time for additional functions, then the time for additional functions is increased, but the pixel charging time is reduced and image quality deteriorates
Solution Approach 1:
The invention applies different quality requirements to different parts of the operation: during the second mode operation, the scan signal frequency is reduced specifically to allow additional functions, while the pixel charging time is maintained adequate by coordinating the data driver operations. This localized adjustment of parameters allows additional functions without compromising overall image quality
Data Source
AI summary
Present invention is related to a display device and a driving method thereof. In particularly, the present invention is to provide a display device and a driving method thereof, in which a data driver driven at a low frequency which is capable of inverting a polarity of a data voltage in each frame.