Pixel Compensation Circuit for OLED Displays with Threshold Voltage Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current pixel compensation circuits in OLED displays face challenges with insufficient threshold compensation during low gray scale data signal charging, leading to longer charging times and reduced brightness due to small charging currents.
Innovation Solution
A pixel compensation circuit comprising a control sub-circuit, write sub-circuit, driving sub-circuit, and light emitting sub-circuit, where the control sub-circuit performs threshold compensation by charging the pixel compensation circuit with a signal from the first power terminal, and a reset sub-circuit sets the light emitting sub-circuit to a reverse bias state to improve performance and extend the lifetime of the electroluminescent device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If conventional pixel compensation circuits charge with low gray scale data signals, then the charging current is small, but the charging time becomes excessively long and threshold compensation is insufficient
Solution Approach 1:
The patent applies preliminary action by performing threshold compensation before the main charging operation. The control sub-circuit first compensates for the threshold voltage of the driving transistor using a compensation signal, ensuring that subsequent charging with low gray scale data signals achieves adequate threshold compensation without requiring excessively long charging times. This preliminary threshold voltage correction enables accurate gray scale display even with small charging currents.
2Duration of action of moving object
If the light emitting sub-circuit operates in forward bias state for extended periods, then it can emit light, but the lifetime and performance of the electroluminescent device deteriorates
Solution Approach 1:
The patent implements periodic action by alternating between forward bias operation and reverse bias recovery states. The reset sub-circuit periodically applies reverse bias voltage to the light emitting sub-circuit during non-display periods (such as during horizontal retrace or frame intervals), allowing the electroluminescent device to recover from accumulated stress. This periodic reverse bias treatment extends device lifetime while maintaining normal forward bias operation for light emission during display periods.
Data Source
AI summary
The present disclosure relates to a pixel compensation circuit and a method of driving the same, a display panel, and a display device. A pixel compensation circuit includes: a control sub-circuit, a write sub-circuit, a driving sub-circuit, and a light emitting sub-circuit, wherein the write sub-circuit is configured to, under the control of a scan signal terminal, transmit a data signal at a data signal terminal to the control sub-circuit and transmit a signal at a reference voltage signal terminal to the control sub-circuit; the control sub-circuit is configured to, under the control of a power control signal terminal, transmit a signal at a first power terminal to the driving sub-circuit, and under the combined action of a conduction control signal terminal and the power control signal terminal, control the driving sub-circuit to perform threshold compensation, and control the driving sub-circuit to generate a driving current to drive the light emitting sub-circuit to emit light.