Temperature-Compensated Scanning Signal Amplitude Control for OLED Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The threshold voltage of driving transistors in organic EL display devices varies with temperature, leading to unstable charging performance of holding capacitors, resulting in inconsistent luminance and color levels across different temperatures.
Innovation Solution
A display device with a temperature detector that adjusts the amplitude of scanning signals and the length of light emission periods based on ambient temperature, ensuring stable charging performance by increasing signal amplitude at lower temperatures and extending or shortening light emission periods accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the same scanning signal amplitude is used for all temperatures, then the device structure is simple, but the charging performance of the holding capacitor varies with temperature causing unstable display quality
Solution Approach 1:
The scanning signal amplitude is made dynamic by adjusting it according to temperature changes. The amplitude is increased when temperature decreases and decreased when temperature increases, allowing the system to adapt to varying thermal conditions and maintain stable charging performance of the holding capacitor across different temperature ranges.
Solution Approach 2:
The invention changes the amplitude parameter of the scanning signal based on temperature conditions. By monitoring temperature and adjusting the signal amplitude accordingly, the system compensates for temperature-induced variations in transistor threshold voltage and maintains consistent charging performance, thereby stabilizing display quality.
2Reliability
If the scanning signal amplitude is increased to compensate for low temperature charging issues, then charging performance at low temperature improves, but overcharging occurs at high temperature
Solution Approach 1:
The scanning signal amplitude is dynamically adjusted based on real-time temperature detection. The system increases amplitude when temperature is low to prevent insufficient charging, and decreases amplitude when temperature is high to prevent overcharging, thereby maintaining optimal charging performance across the entire temperature range.
Solution Approach 2:
The system incorporates temperature detection and uses this feedback to adjust the scanning signal amplitude. By continuously monitoring temperature and responding with appropriate amplitude adjustments, the system prevents both insufficient charging at low temperatures and overcharging at high temperatures, ensuring stable charging performance.
3Reliability
If temperature compensation is implemented, then display quality stability improves, but the control system complexity increases
Solution Approach 1:
The invention implements temperature compensation by adjusting the scanning signal amplitude parameter in response to temperature changes. This parameter adjustment compensates for the temperature-induced variations in transistor threshold voltage, maintaining stable charging performance and consistent luminance output without requiring complex control mechanisms.
Data Source
AI summary
An object of the disclosure is to achieve a stable display quality without an effect of variation in temperature in a display device including a display element driven by an electric current.The display device is provided with a thermistor as a temperature detector detecting an ambient temperature. A scanning signal amplitude controller changes the voltage level of a gate low voltage in accordance with temperature indicated by temperature data acquired by the thermistor. An in-panel driver controller gives, to a gate driver, a gate clock signal of which the voltage level on a high level side is set at the voltage level of a gate high voltage and the voltage level on a low level side is set at the voltage level of the gate low voltage. The gate driver outputs a scanning signal on the basis of the gate clock signal.