Display Device Light Emission Control for Flicker Reduction

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Solution Overview

Problem

Existing display technologies face challenges in achieving high image quality due to mistaken detection and delay in processing high-definition images, leading to uncomfortable visual effects like discontinuous brightness and flickers, especially when switching display control.

Innovation Solution

A method for controlling light emission time and image signal gain based on content type, using a first gain correction portion and a second gain correction portion, along with an average luminance calculation part and a light emission amount regulation part, to adjust light emission time and image signal while maintaining consistent light emission amounts.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If high-definition HD image signal is processed to detect moving image or still image information, then image quality can be improved, but processing delay and mistaken detection occur

Engineering Contradiction:
Improvedetection accuracyVSAvoidprocessing delay
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent applies preliminary action by detecting motion information at a lower resolution stage before full HD processing. The system performs initial motion detection on a down-sampled version of the image signal to determine whether the content is a moving image or still image, thereby avoiding the need to process the entire HD signal for this detection purpose. This preliminary detection at reduced complexity prevents processing delays and mistaken detection while maintaining accurate content identification.

Inventive Principle:
Principle #10Preliminary action

2Reliability

If duty ratio is reduced for moving image to prevent overcurrent, then light emission time is controlled, but discontinuous brightness and flickers occur

Engineering Contradiction:
Improveovercurrent protectionVSAvoidbrightness continuity
Core Design Contradiction:
ReliabilityVSIllumination intensity

Solution Approach 1:

The patent applies dynamics by implementing dynamic duty ratio adjustment based on content type detection. The system dynamically changes the duty ratio according to whether the detected content is a moving image or still image, and according to the average luminance level. For moving images, the duty ratio is adjusted to prevent overcurrent while maintaining brightness continuity through coordinated gain adjustment. This dynamic adaptation resolves the contradiction between overcurrent protection and brightness continuity.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies parameter changes by simultaneously adjusting multiple parameters including duty ratio and gain to maintain consistent light emission amounts. When the duty ratio is reduced for moving image protection, the system compensates by adjusting the gain parameter to maintain brightness continuity. This multi-parameter coordination ensures that overcurrent protection is achieved without causing discontinuous brightness or flickers.

Inventive Principle:
Principle #35Parameter changes

3Illumination intensity

If duty ratio is increased for still image to improve brightness, then light emission time is extended, but overcurrent may occur

Engineering Contradiction:
ImprovebrightnessVSAvoidovercurrent protection
Core Design Contradiction:
Illumination intensityVSReliability

Solution Approach 1:

The patent applies dynamics by implementing dynamic duty ratio adjustment based on content type detection. The system dynamically changes the duty ratio according to whether the detected content is a moving image or still image, and according to the average luminance level. For still images, the duty ratio is increased to improve brightness while monitoring current levels to prevent overcurrent conditions.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies parameter changes by simultaneously adjusting multiple parameters including duty ratio and gain to maintain brightness while preventing overcurrent. When the duty ratio is increased for still image brightness improvement, the system coordinates this with gain adjustment and luminance-based control to ensure that the increased light emission does not cause overcurrent. This multi-parameter coordination resolves the contradiction between brightness improvement and overcurrent protection.

Inventive Principle:
Principle #35Parameter changes

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach enhances image quality by preventing overcurrent and reducing mistaken detection and delay, ensuring a stable and high-quality display experience by finely controlling light emission time and image signal processing.

Implementation Method 1

the organic EL display is a self-light emitting display device that utilizes electroluminescence phenomenon

Methodology Applied
Scientific EffectElectroluminescence: Electroluminescence

Data Source

PatentEP2061020B1Display device, image signal processing method, and program
Publication Date: 2013.10.23 SONY GROUP CORP
  • EP2061020B1 patent drawingFigure 1
  • EP2061020B1 patent drawingFigure 2
  • EP2061020B1 patent drawingFigure 3

AI summary

There is provided a display device equipped with a display unit, the display device including a receiving part for receiving a difference signal of a plurality of channels including an image signal and content identification information inserted in a blanking period and outputting the image signal and the content identification information; a light emission amount regulation part for setting a reference duty according to image information of the image signal; an adjustment part for adjusting so that an actual duty is within a predetermined range based on the reference duty and an adjustment signal and adjusting a gain of the image signal so that a light emission amount defined by the actual duty and the gain of the image signal becomes the same as the light emission amount defined by the reference duty; and an adjustment signal generation part for generating the adjustment signal based on the content identification information.