LCD Driving Method Mitigating Viewing Angle Color Shift
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional large-size LCDs using negative Vertical Alignment (VA) or In-plane Switching (IPS) technology suffer from severe viewing angle color shift due to rapid brightness saturation, affecting image quality.
Innovation Solution
The method involves displaying each picture with two frame images sequentially, with alternate high and low driving voltages, and calculating backlight brightness regulation signals based on average driving voltages to perform brightness adjustments only when the average color chroma of each backlight subarea is within a preset range, using a Look-up table to determine the necessary voltage pairs for each sub-pixel.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional large-size LCDs use negative VA or IPS technology with single frame driving, then the device structure is simple and manufacturing is easy, but the brightness saturates rapidly with driving voltage causing severe viewing angle color shift
Solution Approach 1:
The patent segments each picture into two frame images displayed sequentially, with each frame using different driving voltages for adjacent sub-pixels. This temporal segmentation allows the system to mitigate color shift effects while maintaining a relatively simple display panel structure, resolving the contradiction between structural simplicity and color accuracy.
Solution Approach 2:
The patent implements periodic alternation between high and low driving voltages for adjacent sub-pixels across sequential frames. This periodic voltage modulation prevents brightness saturation and reduces viewing angle color shift while keeping the overall driving scheme manageable, balancing manufacturing ease with improved optical performance.
2Object-affected harmful factors
If the patent uses two frame images with alternate high and low driving voltages for each sub-pixel, then the viewing angle color shift is reduced, but the blinking effect becomes more noticeable and the driving complexity increases
Solution Approach 1:
The patent merges the control of multiple sub-pixels under unified backlight brightness regulation signals. By calculating average driving voltages across sub-pixels and using grouped backlight regulation signals, the system reduces the perceived blinking effect while maintaining the voltage alternation strategy that mitigates color shift, thus improving ease of operation.
Solution Approach 2:
The patent introduces feedback mechanisms where backlight brightness regulation signals are calculated based on average driving voltages from sequential frames. This feedback loop allows dynamic adjustment of backlight brightness to compensate for voltage changes, reducing visible blinking while maintaining color accuracy, and simplifying the overall driving complexity through intelligent control.
3Measurement precision
If backlight brightness regulation is performed for every frame, then the color chroma accuracy is maintained, but the processing time increases and the system response becomes slower
Solution Approach 1:
The patent performs backlight brightness regulation selectively rather than for every frame. By determining whether regulation is needed based on calculated average color chroma and comparing with reference values, the system maintains color chroma accuracy only when necessary, thereby reducing processing time and improving system response without sacrificing color precision.
Data Source
AI summary
A method for driving an LCD device includes displaying each picture with two frame images sequentially; driving voltages for two adjacent sub-pixels in each of the frame images are different, and driving voltages for each sub-pixel in the first frame image and the second frame image are different; determining backlight brightness regulation signals for each of the backlight subareas; the backlight brightness regulation signals are grouped signals, the number of the groups is identical to the number of types of the color sub-pixels; calculating an average color chroma of a current picture region corresponding to each of the backlight subareas; determining whether the average color chroma of each of the backlight subareas is within a preset range; if yes, performing a brightness regulation to a backlight source of the backlight subarea in each of the frame images of a next picture according to the backlight brightness regulation signal of the backlight subarea.