Display Device Block Current Scaling for Luminance Uniformity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices face challenges in maintaining optimal current levels for pixels across different image frames, leading to variations in luminance that can result in either insufficient or excessive current supply, affecting image quality.
Innovation Solution
A display device and driving method that include a timing controller, data driver, current sensor, and scale factor provider to calculate and adjust the target current based on luminous efficiency deviations between blocks, using RGB lookup tables to correct unit target currents and determine scale factors for precise grayscale value scaling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a fixed target current is supplied to all pixels, then the current supply is simple to control, but luminance uniformity deteriorates due to deviations in luminous efficiency between different blocks
Solution Approach 1:
The patent applies local quality by dividing the display into multiple blocks and determining separate target currents for each block based on their specific luminous efficiency characteristics. The scale factor provider calculates different scale factors for each block, allowing each region to receive customized current compensation rather than a uniform approach, thus resolving the luminance uniformity issue while maintaining manageable control complexity.
Solution Approach 2:
The patent changes the target current parameter dynamically based on frame load and block-specific luminous efficiency. By calculating target currents as a function of both the overall frame load and individual block characteristics, the system adapts the current parameter to match actual display conditions, improving luminance uniformity without significantly complicating the control mechanism.
2Manufacturing precision
If the target current is increased to compensate for low luminous efficiency blocks, then luminance uniformity improves, but energy consumption increases
Solution Approach 1:
The patent implements dynamic current adjustment by calculating target currents based on real-time frame load conditions and block-specific luminous efficiency. Rather than using fixed compensation values, the system dynamically adapts the current supply to match actual display requirements, ensuring that energy is consumed only when and where needed to maintain luminance uniformity.
Solution Approach 2:
The system changes the target current parameter based on the frame load, which varies with the displayed image content. By linking target current to frame load, the patent ensures that current compensation is applied proportionally to actual display demands, avoiding unnecessary energy consumption while maintaining luminance uniformity across different blocking conditions.
3Manufacturing precision
If block-specific target currents are calculated to improve luminance uniformity, then luminance uniformity improves, but device complexity increases
Solution Approach 1:
The patent segments the display into multiple blocks and processes each block independently through the scale factor provider. This segmentation allows the system to manage complexity by handling smaller, manageable units rather than the entire display at once, making the complex task of luminance uniformity control more tractable through modular processing.
Solution Approach 2:
The scale factor provider serves multiple functions: it calculates frame load, determines block-specific luminous efficiency, computes scale factors, and generates corrected image data. By consolidating these functions into a single multi-functional component, the patent reduces overall device complexity while achieving the goal of luminance uniformity through block-specific current control.
Data Source
AI summary
A display device includes a display divided into a plurality of blocks including pixels, a timing controller for calculating a frame load for an image frame of input image data, and for generating image data by scaling grayscale values of the input image data using a scale factor, a data driver for generating a data signal corresponding to the image data, and for supplying the data signal to the pixels, a current sensor for sensing a global current flowing in a first power source line connected to the pixels, and a scale factor provider for correcting a unit target current determined using a reference block among the blocks based on a deviation in light emitting characteristics between the blocks, for calculating a target current using the frame load and a corrected unit target current, and for comparing the target current with the global current to calculate the scale factor.