Dummy Pixel Current Detection for Display Degradation Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing image signal processing technologies face challenges in accurately correcting luminance degradation on the low-luminance side of display panels without using expensive luminance sensors, particularly in detecting voltage shifts that affect image quality.
Innovation Solution
An image signal processing circuit with a first dummy pixel outside the effective pixel region, a current detection section to measure current changes, and a modification processing section to adjust the predicted degradation value based on actual degradation amounts, allowing for accurate correction of image signals driving effective pixels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a luminance sensor is used to measure actual degradation state, then correction accuracy is improved, but cost and measurement time are increased
Solution Approach 1:
The patent uses a dummy pixel that copies the electrical characteristics of effective pixels to measure degradation. Instead of using an expensive luminance sensor to directly measure light output, the system creates an electrical copy (dummy pixel) that replicates the transistor degradation behavior, allowing indirect measurement of degradation through current characteristics rather than direct luminance measurement.
Solution Approach 2:
The patent replaces the optical measurement system (luminance sensor measuring light output) with an electrical measurement system (current detection section measuring transistor current). This substitution eliminates the need for expensive optical sensors and reduces measurement time by directly measuring electrical characteristics that correlate with degradation.
2Measurement precision
If a high-performance luminance sensor is used to detect light emission start voltage shift, then measurement accuracy is improved, but cost is increased
Solution Approach 1:
The patent creates an electrical copy of the pixel circuit through the dummy pixel, which replicates the transistor characteristics without requiring the light emission section. This allows measurement of voltage shifts and current characteristics that indicate degradation, eliminating the need for expensive high-performance luminance sensors while maintaining measurement accuracy.
Solution Approach 2:
The dummy pixel serves as an intermediary between the degradation phenomenon and the measurement system. Instead of directly measuring difficult-to-detect voltage shifts with expensive sensors, the dummy pixel translates degradation into measurable current changes that can be detected by simpler, lower-cost detection circuits.
3Measurement precision
If long-time measurement is performed to accurately detect degradation, then correction accuracy is improved, but productivity is reduced
Solution Approach 1:
The patent performs preliminary characterization during manufacturing to establish baseline degradation rates for each panel. By pre-measuring and storing degradation characteristics, the system eliminates the need for lengthy measurements during use, allowing quick correction adjustments while maintaining accuracy. The degradation model is prepared in advance rather than calculated in real-time.
Solution Approach 2:
The dummy pixel provides a rapid electrical copy of degradation characteristics that can be measured quickly without waiting for long-term luminance decay. By measuring current characteristics in the dummy pixel, the system obtains immediate degradation data without requiring extended measurement periods, thus improving adjustment efficiency.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables accurate correction of luminance degradation on the low-luminance side without requiring expensive luminance sensors, improving correction accuracy and reducing costs and user convenience issues.
Implementation Method 1
a current detection section configured to detect a change in a current in the first dummy pixel
Data Source
AI summary
An image signal processing circuit is provided that includes a display panel, a current detection section, a modification processing section, and a correction processing section. The display panel includes a first dummy pixel that is provided outside of an effective pixel region. The current detection section detects a change in a current in the first dummy pixel. The modification processing section modifies a predetermined predicted degradation value based on an actual degradation amount of the detected current. The correction processing section corrects an image signal based on the predetermined predicted degradation value after modification. The image signal is used to drive an effective pixel.