OLED Pixel-Density Voltage Control for Accurate Black Grayscale
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices with varying pixel densities face issues in emitting light with the correct luminance for grayscale due to differing driving characteristics, leading to increased power consumption and the need for additional voltage lines.
Innovation Solution
A display device with separate power voltage settings for areas of different pixel densities, using a second-power voltage setting unit to adjust voltages for black images, and a method to calculate and apply offset voltages based on average grayscales and temperature information to maintain consistent luminance across varying pixel densities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a large margin for voltage is provided to accommodate different driving characteristics, then grayscale accuracy is improved, but power consumption increases
Solution Approach 1:
The patent applies local quality by dividing the display panel into multiple areas with different pixel densities (first area with higher density, second area with lower density) and providing different power voltage settings to each area. The second-power voltage setting unit adjusts the power voltage specifically for the second area based on its pixel density characteristics, allowing each region to operate with optimized voltage levels that match its specific driving characteristics, thereby achieving accurate grayscale representation without unnecessarily increasing power consumption across the entire display.
2Measurement precision
If different voltages are used in different areas to account for pixel density variations, then grayscale accuracy is improved, but the number of necessary voltage lines increases
Solution Approach 1:
The patent applies universality by designing a second-power voltage setting unit that can dynamically adjust power voltage levels for the second area based on pixel density characteristics. Instead of creating separate voltage lines for each pixel density variation, the system uses a multi-functional voltage setting unit that can adaptively provide appropriate voltage levels through existing power supply infrastructure, thereby achieving area-specific voltage optimization without proportionally increasing the number of voltage lines.
3Ease of manufacture
If common voltage settings are used for all display devices, then manufacturing complexity is reduced, but driving characteristic variations cause incorrect luminance
Solution Approach 1:
The patent applies dynamics by implementing a second-power voltage setting unit that dynamically adjusts power voltage levels for the second area based on its specific pixel density characteristics. Rather than using fixed common voltage settings for all areas, the system enables adaptive voltage adjustment that responds to the specific driving characteristics of each area, thereby achieving accurate luminance control while maintaining relatively simple manufacturing processes through programmable voltage control.
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
The solution allows for the expression of desired black and white grayscales with a minimum number of lines, minimizing display delay and reducing power consumption by optimizing voltage settings for different pixel areas.
Implementation Method 1
a light emitting element including an anode connected to a fourth node and a cathode for receiving the first power voltage
Data Source
AI summary
A display device includes: a pixel unit including a first area including first pixels disposed with a first density and a second area including second pixels disposed with a second density smaller than the first density; a power supply for supplying a first power voltage commonly supplied to cathodes of first light emitting elements of the first pixels; and a second-power voltage setting unit for setting a magnitude of a second power voltage commonly supplied to cathodes of second light emitting elements of the second pixels. When the pixel unit displays a black image, the second-power voltage setting unit sets the second power voltage to be higher than the first power voltage.