Luminance Compensation for Local and Global Dimming Displays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid-crystal displays (LCDs) face issues with light leakage and lower contrast ratio compared to OLEDs, and local dimming displays experience the halo effect around bright objects in dark backgrounds and low brightness in dimmed zones.
Innovation Solution
A method and system that adjust input images based on perceived appearances on target and ideal displays through simulations, using pixel compensation and luminance retargeting processes to match the quality of ideal displays, thereby reducing light leakage and halo effects.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If local dimming is used to improve contrast ratio, then contrast ratio is improved, but halo effect appears around bright objects in dark background
Solution Approach 1:
The patent applies local quality by implementing different luminance compensation strategies for different regions of the display. The system divides the display into multiple local dimming zones and applies pixel compensation and luminance retargeting specifically to affected regions, allowing high contrast in dark zones while preventing halo effects around bright objects through region-specific adjustment.
Solution Approach 2:
The patent changes luminance parameters dynamically through pixel compensation and luminance retargeting processes. The system adjusts luminance values of individual pixels or small groups of pixels based on their local context, modifying brightness parameters to eliminate halo effects while preserving the contrast benefits of local dimming.
2Manufacturing precision
If local dimming is used to improve contrast ratio, then contrast ratio is improved, but brightness in locally dimmed dark zones becomes too low
Solution Approach 1:
The patent dynamically adjusts luminance parameters in dark zones through pixel compensation and luminance retargeting. The system analyzes the perceived appearance on both target and ideal displays, then modifies luminance values in dimmed zones to maintain adequate brightness while preserving the high contrast ratio benefit of local dimming.
Solution Approach 2:
The patent employs feedback mechanisms by comparing the target display perceived appearance with the ideal display perceived appearance. This comparison provides feedback that guides the pixel compensation and luminance retargeting processes, ensuring that brightness in dark zones is adjusted to match ideal display performance while maintaining local dimming contrast benefits.
3Manufacturing precision
If global dimming is used to improve overall image quality, then image quality is improved, but light leakage occurs
Solution Approach 1:
The patent segments the display into multiple local dimming zones, allowing independent control of backlight intensity in different regions. This segmentation enables the system to dim only the necessary zones while keeping other zones at appropriate brightness levels, thereby reducing overall light leakage while maintaining image quality through localized control.
Solution Approach 2:
The patent applies local quality by implementing region-specific luminance compensation and pixel adjustment. Different parts of the display receive tailored compensation based on their local characteristics, allowing the system to suppress light leakage in specific zones while maintaining appropriate brightness and image quality in other regions.
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
A system and method is provided for adjusting an input image based on a perceived appearance of the input image on a target display and on an ideal display. The method includes: receiving an input image; determining a target display perceived appearance of the input image, wherein the target display perceived appearance represents a perceived appearance of the input image according to a target display; determining an ideal display perceived appearance of the input image, wherein the ideal display perceived appearance represents a perceived appearance of the input image according to an ideal display; and adjusting the input image based on the target display perceived appearance and the ideal display perceived appearance.