Display Device Pixel Region Transistor Channel Ratio Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Organic light emitting display devices experience brightness differences due to varying load values of wiring lines, which affect image uniformity across pixels.
Innovation Solution
The display device incorporates pixel regions with different widths, utilizing transistors and capacitors with varying channel width-to-length ratios and capacities to compensate for brightness differences by adjusting the RC load values and voltage storage across regions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If wiring lines are extended to cover more pixels, then the display area is increased, but the load value of wiring lines increases causing brightness difference
Solution Approach 1:
The patent applies local quality by dividing the display into multiple pixel regions with different widths, where each region has transistors with specifically designed channel width-to-length ratios tailored to that region's wiring load characteristics. This allows each local area to be optimized for its specific electrical characteristics, compensating for the brightness differences caused by varying wiring line lengths and loads across the display area.
Solution Approach 2:
The patent changes the channel width-to-length ratio parameter of transistors across different pixel regions to compensate for varying wiring loads. By adjusting this critical transistor parameter based on position, the invention balances the electrical characteristics across the display, maintaining uniform brightness despite differences in wiring line lengths.
2Illumination intensity
If transistors with different channel width-to-length ratios are used in different pixel regions, then brightness uniformity is improved, but device complexity increases
Solution Approach 1:
The patent segments the display into multiple pixel regions with different width characteristics, and assigns appropriate transistor configurations to each segment. This segmentation approach allows the complexity to be managed in a structured way, where each region's transistor parameters are optimized independently based on its specific wiring load, rather than attempting to uniformize the entire display.
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
A display device includes a first pixel region (PA1) and a second pixel region (PA2) having different widths (WD1, WD2). First pixels (PXL1) in the first pixel region each include a first transistor. Second pixels (PXL2) in the second pixel region each include a second transistor performing a same function as the first transistor. At least one of a channel width and a channel length of the first transistor of the first and second pixels is be different from one another.