Display Device Current Compensator for Hot-Spot Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Display devices face issues with current concentration on light-emitting elements leading to hot-spots and deterioration due to defects like contact or conduction defects, which result in reduced lifespan and efficiency.
Innovation Solution
A display device and method that include a current compensator to detect voltage differences across light-emitting stages and provide compensation currents to limit maximum current flow, using a current mirror unit and reference current generator to adjust compensation voltages based on detected differences, ensuring the sum of total and compensation currents equals the driving current.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If light-emitting elements are connected in parallel to increase brightness and current handling capability, then the total light output and current capacity are improved, but current concentration occurs due to defects leading to hot-spots and reduced reliability
Solution Approach 1:
The patent implements a feedback mechanism by detecting the voltage difference across each light-emitting element and using this information to dynamically adjust the compensation current. The detector monitors voltage differences, and the current compensator adjusts compensation currents based on detected voltage differences, creating a closed-loop control system that maintains uniform current distribution despite element variations or defects
Solution Approach 2:
The patent changes the electrical parameters (voltage and current) dynamically based on detected conditions. By adjusting the compensation current magnitude according to the detected voltage difference, the system adapts to varying element characteristics and defect conditions, optimizing current distribution in real-time
2Reliability
If compensation current is provided to all light-emitting elements to ensure uniform current distribution, then current concentration is reduced, but the device complexity and power consumption increase
Solution Approach 1:
The patent applies local quality by providing compensation current selectively to specific light-emitting elements based on their individual needs. Instead of uniform compensation to all elements, the system detects voltage differences for each element and provides compensation current only where necessary, making the compensation tailored to local conditions
Solution Approach 2:
The patent uses partial action by providing compensation current only to light-emitting elements that exhibit voltage differences indicating current concentration. The compensation is applied selectively rather than universally, reducing unnecessary power consumption and circuit activity while maintaining reliability
3Reliability
If detection and compensation circuits are added to each light-emitting element to prevent current concentration, then current distribution uniformity is improved, but the manufacturing complexity and cost increase
Solution Approach 1:
The patent implements universality by using shared components (detector and current compensator) that serve multiple light-emitting elements. Rather than dedicating separate detection and compensation circuits to each element, the system uses common circuits that can monitor and adjust currents across multiple elements, simplifying manufacturing
Solution Approach 2:
The patent merges the detection and compensation functions into integrated circuits that work together as a unified system. The detector and current compensator are combined into a coordinated compensation mechanism, reducing the number of discrete components and simplifying the manufacturing process
Data Source
AI summary
A display device includes a pixel circuit configured to generate a driving current based on a data signal supplied to a data line, a first light-emitting stage configured to emit light based on the driving current, and including first light-emitting elements connected in parallel, a detector configured to detect voltages of respective ends of the first light-emitting stage, and a current compensator configured to compensate for a current flowing through the first light-emitting stage based on a first voltage difference between the voltages of the respective ends of the first light-emitting stage.