Pixel Reference Voltage Control for Low-Frequency Flicker Reduction
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Solution Overview
Problem
Display devices face issues with increased power consumption and image flickering when operating at low driving frequencies due to leakage of driving current, which existing methods like floating node control do not adequately address.
Innovation Solution
The display device adjusts the reference voltage supplied to pixels based on variations in driving frequency and representative grayscale, using a controller to generate reference voltage data that minimizes leakage current and mitigates flickering by controlling the reference voltage in response to frame frequency changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the driving frequency is decreased to reduce power consumption, then power consumption is reduced, but leakage current increases causing image flickering
Solution Approach 1:
The patent adjusts the reference voltage level as a parameter to compensate for leakage current effects at different driving frequencies. By dynamically changing the reference voltage based on the driving frequency, the system maintains stable pixel operation and prevents image flickering while operating at low frequencies for reduced power consumption.
Solution Approach 2:
The system implements feedback by monitoring the driving frequency and adjusting the reference voltage accordingly. The controller modifies the reference voltage level based on the detected driving frequency to compensate for leakage current, ensuring stable image display even when operating at low frequencies for power savings.
2Use of energy by moving object
If the driving frequency is decreased to reduce power consumption, then power consumption is reduced, but leakage current occurs in pixels
Solution Approach 1:
The patent changes the reference voltage parameter to counteract leakage current effects. By adjusting the reference voltage level according to the driving frequency, the system compensates for charge loss due to leakage, maintaining proper pixel voltage levels while operating at low frequencies for reduced power consumption.
Solution Approach 2:
The system uses feedback mechanisms to detect driving frequency and adjust the reference voltage to compensate for leakage current. This closed-loop control ensures that leakage current effects are minimized while maintaining low-power operation at reduced driving frequencies.
3Reliability
If the reference voltage is adjusted based on driving frequency and grayscale, then leakage current is minimized and flickering is reduced, but device complexity increases
Solution Approach 1:
The patent pre-calculates and stores reference voltage values corresponding to different driving frequencies and grayscale levels in a lookup table. This preliminary preparation allows the controller to quickly retrieve the appropriate reference voltage without complex real-time calculations, reducing the control circuit complexity while maintaining image stability.
Solution Approach 2:
The system uses a lookup table that stores pre-determined reference voltage values for various driving frequencies and grayscale combinations. By copying the appropriate pre-calculated value from the table rather than computing it in real-time, the system simplifies the control circuit while achieving reliable leakage current compensation and flicker reduction.
Data Source
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AI summary
A display device includes: a pixel configured to display an image based on image data and a reference voltage; a controller configured to generate reference voltage data corresponding to the reference voltage for restraining leakage current in the pixel based on a frame frequency; and a power supply configured to generate the reference voltage based on the reference voltage data and supply the reference voltage to the pixel.