Dummy Pixel Circuit Sensing for Accurate Display Degradation Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing display devices face challenges in accurately measuring compensation values due to limited sensing times and noise interference during electrical characteristic degradation of pixels, which affects display quality over time.
Innovation Solution
Incorporating a dummy pixel circuit in a non-display area to sense and generate compensation information for pixel degradation, using a sensing unit to input test data signals, convert output signals, and calculate accurate compensation values by comparing with reference values, thereby compensating for pixel degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If sensing is performed multiple times to improve measurement accuracy, then measurement precision improves, but sensing time increases and noise interference worsens
Solution Approach 1:
The dummy pixel circuit performs preliminary degradation sensing in a non-display area before actual display pixels are affected. By pre-measuring degradation characteristics in the dummy circuit under controlled conditions, the system obtains compensation data without requiring multiple repeated measurements on display pixels, thus reducing sensing time while maintaining accuracy.
Solution Approach 2:
The dummy pixel circuit acts as an intermediary that separates the measurement function from the display function. It receives the same degradation characteristics as display pixels but allows sensing operations to be performed independently without interfering with normal display operation, eliminating noise from display driving signals during measurement.
2Measurement precision
If sensing operations are performed frequently to track degradation, then measurement precision improves, but noise interference increases
Solution Approach 1:
The sensing function is extracted from the display pixel circuit and relocated to a dedicated dummy pixel circuit in the non-display area. This separation removes the harmful noise from display driving voltages during sensing operations, as the dummy circuit can be measured independently without active display scanning or data signal interference.
Solution Approach 2:
A dummy pixel circuit is created as a copy of the actual pixel circuit structure, containing identical transistors and capacitors that exhibit the same degradation characteristics. This copy allows repeated sensing operations to be performed without affecting the original display pixels, enabling frequent measurements for high precision while avoiding noise from display operation.
3Measurement precision
If compensation sensing is performed for all pixels, then measurement precision improves, but device complexity increases
Solution Approach 1:
The dummy pixel circuit serves multiple functions: it replicates the degradation characteristics of display pixels, provides a testbed for sensing operations, and generates compensation data applicable to all display pixels. This single multi-functional component replaces what would otherwise require individual sensing circuits for each pixel, significantly reducing system complexity while maintaining the ability to perform precise compensation measurements.
Data Source
AI summary
A display device comprising pixel circuits included in the display area, the pixel circuits including light emitting elements with grayscales corresponding to data input from the outside, a dummy pixel circuit included in the non-display area, the dummy pixel circuit including a dummy light emitting element and a dummy driving transistor, a sensing unit for inputting, to the dummy pixel circuit, a test data signal for sensing an output signal corresponding to predetermined test data for each predetermined time, and then performing an operation of generating compensation information for compensating for degradation according to a driving time of at least one of the light emitting element and the driving transistor based on the output signal output from the dummy pixel circuit, and a timing controller for accumulating and storing the compensation information, and generating compensated data by compensating for the data input from the outside.