Local Dimming Control for Display Non-Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional local dimming techniques struggle to achieve high contrast and deep black levels, particularly in areas requiring complete black, such as corners or edges, due to limitations in brightness and black characteristic control, and non-uniformity in backlight emission areas.
Innovation Solution
An image data processing device that calculates a representative brightness value by analyzing black image data, considering the ratio of black levels and applying a gamma variable, and adjusts for non-uniformity between blocks to enhance brightness or black characteristics, allowing flexible dimming control through a dimming value calculation and output to a backlight driving device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If conventional local dimming method is used to reduce power consumption, then power consumption is reduced, but contrast and deep black levels deteriorate
Solution Approach 1:
The patent applies local quality by calculating separate representative brightness values for different blocks (e.g., corner blocks, edge blocks, center blocks) rather than using a single average value for the entire screen. This allows each region to have optimized dimming control tailored to its specific characteristics, achieving deep black levels in dark regions while maintaining brightness in light regions, thus improving contrast without significantly increasing overall power consumption.
Solution Approach 2:
The patent changes the parameter calculation method from simple average of maximum grey scale values to a more sophisticated method that considers black image data ratios and applies gamma variables. This parameter transformation enables the system to achieve better black levels and contrast by adjusting the representative brightness values based on actual image content and regional characteristics.
2Device complexity
If conventional local dimming method is used, then implementation is simple, but flexibility in brightness and black control deteriorates
Solution Approach 1:
The patent introduces dynamic control by allowing selective application of gamma variables and different representative brightness value calculations for different blocks based on their positions and image content. The system can dynamically adjust whether to emphasize brightness or black characteristics in each region, providing flexibility without significantly increasing implementation complexity through the use of standardized processing steps.
3Device complexity
If uniform backlight emission area is assumed, then calculation is simplified, but brightness uniformity between regions deteriorates
Solution Approach 1:
The patent addresses brightness non-uniformity by calculating separate representative brightness values for different blocks (corner, edge, center) rather than assuming uniform emission across the entire backlight area. This local calculation approach compensates for the non-uniform light distribution characteristics of the backlight, ensuring consistent brightness perception across different regions of the display.
Data Source
AI summary
The present disclosure may improve contrast and deep black by efficiently controlling local dimming in consideration of the ratio of a black image data and the non-uniformity in the area between blocks.