Display Driver IC Stress Compensation for OLED Image Sticking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices, particularly electroluminescent displays like OLEDs, suffer from image sticking due to degradation of driving transistors and OLEDs over time, leading to image quality issues.
Innovation Solution
A display driver integrated circuit (DDIC) with a compensation circuit that includes a memory, sampler, and data processor to accumulate stress data, detect abnormalities, and perform image sticking compensation by comparing degradation values across frames, ensuring integrity of the data and preventing mis-compensation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If image sticking compensation is performed using accumulated stress data, then image quality is improved, but data integrity may be compromised due to defects in the accumulated data
Solution Approach 1:
The patent implements a feedback mechanism where the data processor continuously monitors the accumulated stress data by comparing maximum values across frames. When abnormalities are detected (such as sudden changes exceeding a threshold), the system generates feedback signals to halt compensation operations, thereby preventing propagation of corrupted data while maintaining overall image quality compensation effectiveness
Solution Approach 2:
The patent introduces an intermediary verification mechanism where a separate data processor acts as a mediator between the accumulator and the compensator. This intermediary component validates data integrity through maximum value comparison and abnormal detection before allowing compensation operations to proceed, thus protecting against data corruption while enabling compensation functionality
2Measurement precision
If accumulated stress data is continuously updated, then compensation accuracy is improved, but abnormal data may be stored leading to mis-compensation
Solution Approach 1:
The patent applies preliminary action by performing abnormal detection before data storage. The data processor compares maximum values of current and previous frames beforehand, and only stores data in the accumulator if the difference is within the acceptable threshold. This preliminary verification prevents corrupted data from entering the accumulation process, maintaining both accuracy and reliability
Solution Approach 2:
The system implements feedback control where the data processor continuously monitors accumulated data for abnormalities and provides feedback to halt updates when threshold violations occur. This feedback mechanism ensures that only valid data is accumulated, maintaining measurement precision while preventing mis-compensation from corrupted data
3Loss of information
If the data processor checks for abnormalities in slice accumulated data, then data integrity is improved, but processing time increases
Solution Approach 1:
The patent applies segmentation by dividing the image data into slices (e.g., pixel rows or columns) and processing them independently. The data processor checks abnormalities in each slice separately by comparing maximum values, which allows parallel processing and reduces overall verification time while maintaining comprehensive data integrity checking across the entire image
Data Source
AI summary
A display driver integrated circuit includes a first memory, a compensator, a sampler and a data processor. The first memory stores accumulated stress data. The compensator generates an output data for image display by compensating an input image data based on the accumulated stress data. The sampler selects a slice data. The data processor generates a present slice accumulated data of a present slice accumulated data set by summing the selected slice data with a previous slice accumulated data of a previous slice accumulated data set, selects a maximum value as a present maximum value, determines whether the present slice accumulated data is abnormal based on comparing a previous maximum value of the previous slice accumulated data set with the present maximum value and selectively updates the previous slice accumulated data set by selectively storing the present slice accumulated data set in the first memory based on the determination.