OLED Pixel Layout With Unequal Transistors for Color Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current organic light emitting diode (OLED) displays face challenges in controlling red, green, and blue light emissions due to differing emission efficiencies, which affects the pixel aperture ratio and overall display performance.
Innovation Solution
The OLED display design includes pixels with driving transistors of varying areas and lengths, matched to the emission efficiencies of red, green, and blue light emitting elements, with a matrix arrangement of pixels and alternating gate lines to optimize current driving and aperture ratio.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If pixels are designed based on the lowest emission efficiency to control red, green, and blue light emissions in an equivalent manner, then color uniformity is improved, but pixel aperture ratio decreases
Solution Approach 1:
The patent applies local quality by making the driving transistor channel widths different for red, green, and blue pixels. Specifically, the channel width of the driving transistor is adjusted according to the emission efficiency of each color: wider for lower efficiency colors (red), narrower for higher efficiency colors (blue). This local differentiation allows each pixel to emit equivalent light intensity despite different material efficiencies, resolving the contradiction between color uniformity and aperture ratio by optimizing transistor dimensions locally rather than using uniform pixel designs.
2Manufacturing precision
If driving transistors of different areas are used for first, second, and third pixels, then light emission control is improved, but device complexity increases
Solution Approach 1:
The patent implements parameter changes by systematically varying the channel width parameter of driving transistors across different pixel types. The channel width is changed according to a predetermined pattern corresponding to the emission efficiency characteristics of red, green, and blue light emitting materials. This parameter adjustment approach allows precise control of light emission intensity while maintaining a relatively simple device structure, as only the transistor channel width parameter needs to be modified rather than introducing entirely different transistor designs or additional components.
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 design ensures uniform color mixing and improved light emission efficiency by matching transistor sizes to emission efficiencies, enhancing the display's ability to control light emissions and maintain a high aperture ratio.
Implementation Method 1
Excitons are formed when the injected electrons and holes recombine, and emit light by discharging energy
Data Source
AI summary
An organic light emitting diode display includes a plurality of pixels. Each pixel includes a light emitting element and a driving transistor coupled to the light emitting element. The pixels may be arranged in a matrix. The pixels include first pixels, second pixels, and third pixels, the driving transistors of the first to the third pixels occupy different areas, and the light emitting elements of the first to the third pixels occupy substantially equal area.