OLED Pixel Circuit Compensation for Threshold Voltage Drift
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In OLED display panels, threshold voltage drift can lead to inaccurate compensation values due to potential broken or short circuits in sense lines or switching transistors, resulting in abnormal image display.
Innovation Solution
A pixel circuit compensation method that acquires threshold voltages for each subpixel, determines abnormal voltages by comparing them within a predetermined range, and adjusts compensation signals using alternative voltages from adjacent subpixels to ensure accurate compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If threshold voltage is detected at sensing stage to provide compensation value, then compensation can be provided for threshold voltage drift, but broken circuit or short circuit in sense line or switching transistor may occur causing inaccurate threshold voltage collection and inaccurate compensation
Solution Approach 1:
The patent applies preliminary action by detecting abnormal voltages in the threshold voltage data before applying compensation. The method includes: acquiring threshold voltage data for all subpixels, detecting abnormal voltage values through comparison with reference ranges or adjacent subpixels, correcting the abnormal data before compensation application, and then applying the corrected compensation values. This preliminary detection and correction prevents inaccurate compensation caused by circuit failures.
Solution Approach 2:
The patent uses an intermediary approach by introducing reference voltage ranges and adjacent subpixel voltage values as mediators to identify and correct abnormal threshold voltage data. Instead of directly using potentially corrupted sensing data, the method compares detected voltages against these intermediary references to identify anomalies and replace them with corrected values before applying compensation.
2Ease of manufacture
If threshold voltage compensation is applied to all subpixels uniformly, then compensation process is simple, but abnormal subpixels with circuit failures will receive incorrect compensation values leading to image distortion
Solution Approach 1:
The patent applies local quality by differentiating the compensation process for normal and abnormal subpixels. Instead of uniform compensation, the method identifies abnormal subpixels through voltage detection and comparison, then applies different compensation strategies: normal subpixels receive standard compensation while abnormal subpixels receive corrected compensation based on adjacent subpixel values or reference ranges. This localized approach maintains simplicity while improving accuracy.
Data Source
AI summary
A pixel circuit compensation method is provided, including: acquiring a threshold voltage of a driving transistor in each subpixel of a display panel; determining whether there is an abnormal voltage in the threshold voltages; and when there is the abnormal voltage, adjusting a compensation signal to be applied to a first subpixel corresponding to the abnormal voltage.