Liquid Crystal Display Backlight Control for Blur Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional liquid crystal displays face the dilemma of image blurs when back light is always on and insufficient brightness when back light is only provided during vertical blanking intervals, affecting the viewing experience, especially for dynamic videos.
Innovation Solution
A displaying method that uses a periodic time sequence with adjustable backlight intensity, providing the backlight after the end of the first scanning time period and maintaining the same frame image data across subsequent scanning periods to reduce blurs and enhance brightness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If the back light is present all the time, then the image brightness is sufficient, but the transition of the liquid crystal cells is observed by users, resulting in a blur
Solution Approach 1:
The backlight is controlled to operate periodically, turning on during vertical blanking intervals when liquid crystal cells are stable and turning off during scanning periods when cells are transitioning. This periodic operation eliminates image blur while maintaining sufficient brightness during the intervals when the backlight is on.
Solution Approach 2:
The backlight is activated before the scanning period begins (during vertical blanking interval) to ensure liquid crystal cells have completed their transition and stabilized before illumination occurs. This preliminary timing prevents observation of cell transitions by users.
2Object-affected harmful factors
If the back light is provided only within intervals between frame scans (vertical blanking intervals), then the blur problem is eliminated effectively, but the image brightness is insufficient
Solution Approach 1:
The backlight intensity is made dynamically adjustable rather than fixed. The control module can adjust the backlight intensity to different levels to compensate for the reduced duty cycle, ensuring sufficient image brightness is achieved even when the backlight operates only during vertical blanking intervals.
3Illumination intensity
If the back light is provided during scanning time periods, then the image brightness is sufficient, but the liquid crystal cell switching is observed, causing blur across the whole frame
Solution Approach 1:
The system employs periodic backlight operation synchronized with the display refresh cycle, activating the backlight only during vertical blanking intervals when no scanning occurs. This timing coordination ensures that liquid crystal cell transitions complete before illumination begins, eliminating blur while maintaining display precision.
Data Source
AI summary
A displaying method for a displaying apparatus having a liquid crystal display panel for displaying images thereon is used for displaying images in accordance with a periodic time sequence. The periodic time sequence includes a plurality of scanning time periods and a plurality of vertical blanking intervals. The scanning time periods and the vertical blanking intervals are staggered. The displaying method includes the steps of: providing a substantially identical frame image data by a control module of the displaying apparatus to the liquid crystal display panel for each scanning time period; and providing a back light by a backlight module of the displaying apparatus to the liquid crystal display panel after an end point of the first one of the scanning time periods. Therein, the back light has a light intensity. Further, the light intensity can be designed to be adjustable.