LCD Backlight Power Reduction via Error Data Bitmap Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Liquid crystal display (LCD) devices face challenges in reducing power consumption of the backlight unit while maintaining image quality, as existing methods may lead to image degradation due to dense disposition of error data.
Innovation Solution
A method of driving LCD devices involves inputting source image data, defining error data, generating conversion image data with increased gray levels, and controlling backlight brightness, along with forming a bitmap to detect positional distribution of error data and adjusting the number of error areas to prevent image degradation and reduce power consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by stationary object
If error data are defined from source image data to reduce backlight power consumption, then power consumption decreases, but image quality degrades due to dense disposition of error data
Solution Approach 1:
The patent applies local quality by differentiating the treatment of error data based on their spatial distribution. Instead of uniformly handling all error data, the invention identifies regions with dense error data disposition and applies specific corrections to those local areas. The bitmap analysis detects clusters of error data, and the image processing selectively adjusts only those regions where error data are densely disposed, thereby maintaining image quality in critical areas while still achieving power consumption reduction through error data definition in other regions.
2Manufacturing precision
If modulation factor is increased to enhance image brightness, then image quality improves, but backlight power consumption increases
Solution Approach 1:
The patent employs parameter changes by dynamically adjusting the modulation factor based on the actual distribution of error data in the image. Rather than using a fixed or uniformly high modulation factor, the system calculates the modulation factor locally in regions where error data are densely disposed, applying higher modulation only where necessary to maintain image quality. In regions with sparse error data, a lower modulation factor suffices, thereby reducing overall backlight power consumption while maintaining adequate image brightness where it matters most.
Data Source
AI summary
A method of driving a liquid crystal display device includes inputting source image data, each of which has one of m gray level values, wherein m is a natural number, defining T error data from the source image data, wherein the error data have top k gray level values, and T and k are a natural number, generating conversion image data having larger gray level values than the source image data using one having a largest gray level value from the source image data excluding the error data, inputting the conversion image data to a liquid crystal panel, controlling a brightness of a backlight unit in accordance with the conversion image data, forming a bitmap corresponding to the conversion image data, wherein the bitmap shows positional distribution of pixels with the error data, counting error areas by scanning the bitmap, wherein each of the error areas includes the predetermined number of the pixels having the error data, and controlling the T according to the number of the error.