Subpixel Reference-Line Sensing for Display Defect Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices face issues with non-uniform subpixel characteristics and degradation over time, leading to instability and reduced reliability and lifespan.
Innovation Solution
A display device with a sensing circuit that acquires and compares sampling values during different reference voltage periods to determine defects in subpixels, using a timing controller to control the sensing and driving circuits, and a method that includes first and second sensing periods to accurately identify defective subpixels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If subpixels are used in display devices, then display functionality is achieved, but non-uniform characteristics and degradation occur over time
Solution Approach 1:
The patent applies preliminary action by performing sensing operations before actual display operations to detect defective subpixels in advance. The sensing circuit measures voltage differences across reference lines during sensing periods to identify subpixels with abnormal characteristics before they cause display issues, enabling preventive compensation or replacement.
Solution Approach 2:
The patent implements feedback through the sensing circuit that continuously monitors voltage differences in reference lines and provides this information back to the timing controller. Based on this feedback, the system can identify degraded subpixels and adjust driving parameters or compensate for their non-uniform characteristics, thereby maintaining driving stability throughout the display device's lifespan.
2Measurement precision
If sensing operations are performed to detect defects, then defect detection accuracy is improved, but additional sensing periods increase device complexity
Solution Approach 1:
The patent applies universality by designing the sensing circuit to serve multiple functions: it not only detects defective subpixels but also measures voltage differences across reference lines to characterize subpixel degradation levels. The same sensing circuit is used for both defect detection and performance characterization, reducing overall device complexity while maintaining high measurement precision.
Solution Approach 2:
The patent implements periodic action by integrating sensing periods into the existing display timing cycle. Sensing operations are performed periodically during specific time windows within each frame cycle, allowing defect detection without requiring continuous additional hardware or permanently increasing device complexity. The sensing circuit operates alternately with display operations.
3Measurement precision
If multiple sensing periods are implemented, then defect determination accuracy is improved, but driving time is reduced
Solution Approach 1:
The patent applies periodic action by scheduling sensing operations during specific time windows within the display refresh cycle. Multiple sensing periods are distributed across different frames or time slots, allowing accurate defect determination while minimizing impact on overall driving speed. The sensing circuit operates during blanking periods or between display updates, maintaining productivity.
Solution Approach 2:
The patent implements partial action by performing sensing operations only on selected reference lines or specific time periods rather than continuously monitoring all subpixels. This selective sensing approach maintains sufficient defect determination accuracy while reducing the total time consumed, thereby preserving driving speed and productivity.
Data Source
AI summary
A display device can include a display panel including a subpixel having a switching transistor connected to a data line and a sensing transistor connected to a reference line, a driving circuit connected to the data line, a sensing circuit connected to the reference line; and a timing controller. Also, the sensing circuit is configured to in response to applying a first reference voltage to the subpixel during a first sensing period, acquire a first sensing voltage charged in the reference line as a first sampling value when the switching and sensing transistors are turned on and acquire the first sensing voltage charged in the reference line as a second sampling value when the switching and sensing transistors are turned off, and the timing controller determines that the display device has a defect based on a first difference value between the first sampling value and the second sampling value.