Liquid Crystal Display Pixel Structure with Asymmetric Storage Capacitors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid crystal display panels using the dot inversion driving method often produce a greenish frame due to unbalanced polarity, leading to reduced gray scale display for red and blue sub-pixels and insufficient brightness or flicker.
Innovation Solution
The pixel structure includes a first and second sub-pixel region with storage capacitors, where the second storage capacitor is larger than the first, and adjusting capacitors, allowing for balanced coupling effects and pixel voltages across sub-pixels to mitigate the greenish frame issue.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the dot inversion driving method is used to drive the liquid crystal display panel, then the polarity inversion can be achieved to prevent liquid crystal molecule permanent deformation, but the common voltage shifts toward high voltage level causing unbalanced polarity and greenish frame
Solution Approach 1:
The patent applies different storage capacitor values to different sub-pixel types (red, green, blue) to compensate for the unbalanced polarity effect. Specifically, the green sub-pixel is assigned a larger storage capacitor than the red and blue sub-pixels, which have equal and smaller capacitances. This local differentiation in capacitor values balances the coupling effect between pixel electrodes and common voltage, eliminating the greenish frame while maintaining the benefits of dot inversion driving.
2Power
If the common voltage is affected by data signals to shift toward high voltage level, then the voltage difference for driving red/blue sub-pixels is reduced, but the voltage difference for driving green sub-pixels is increased causing unbalanced gray scale display
Solution Approach 1:
The patent changes the parameter of storage capacitor value differently for different sub-pixel types. By setting Cg_red = Cg_blue < Cg_green, the patent adjusts the electrical parameters to compensate for the common voltage shift. This parameter differentiation ensures that all sub-pixels experience balanced voltage differences and coupling effects, achieving consistent gray scale display across red, green, and blue sub-pixels.
Data Source
AI summary
A pixel structure includes at least one first sub-pixel electrode, at least one second sub-pixel electrode, at least one common line, at least one first transistor electrically connected to the first sub-pixel electrode, and at least one second transistor electrically connected to the second sub-pixel electrode. The common line overlaps and is coupled respectively with the first sub-pixel electrode and the second sub-pixel electrode so as to respectively form a first storage capacitor and a second storage capacitor. The second storage capacitor is larger than the first storage capacitor. A first adjusting capacitor of the first transistor is larger than a second adjusting capacitor of the second transistor.