Display Brightness Adjustment Using APL-Based Light Curves

Solution Overview

Problem

Conventional display technologies, such as OLEDs, face challenges in maintaining high contrast and reducing power consumption when adjusting brightness, particularly at low average pixel levels, leading to reduced image contrast and increased eye irritation in HDR displays.

Innovation Solution

A display brightness adjustment method that uses different light adjustment curves based on average pixel levels to determine actual display brightness values, transitioning from peak brightness to a brightness value obtained by multiplying peak brightness and a gain value, thereby reducing contrast impact and improving HDR display quality.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by stationary object

If brightness is adjusted based on a single light adjustment curve obtained by multiplying the peak lightness curve and a brightness gain value, then power consumption is reduced at high APL, but image contrast is greatly reduced at low APL

Engineering Contradiction:

Improvepower consumptionVSAvoidimage contrast

Core Design Contradiction:

Use of energy by stationary objectVSIllumination intensity

Solution Approach 1:

The patent divides the brightness adjustment into three distinct segments based on APL ranges: first light adjustment curve for APL≤10%, second light adjustment curve for 10%<APL≤50%, and third light adjustment curve for APL>50%. Each segment uses a different adjustment strategy optimized for its specific APL range, allowing contrast preservation at low APL while maintaining power efficiency at high APL.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies different light adjustment characteristics to different APL regions. At low APL (≤10%), the first light adjustment curve maintains peak brightness to preserve contrast. At intermediate APL (10%-50%), the second curve provides moderate adjustment. At high APL (>50%), the third curve applies stronger brightness reduction to save power. This localized optimization resolves the contradiction between contrast and power consumption.

Inventive Principle:

Principle #3Local quality

2Illumination intensity

If peak brightness is maintained at low APL to preserve contrast, then image quality is improved, but power consumption increases

Engineering Contradiction:

Improveimage contrastVSAvoidpower consumption

Core Design Contradiction:

Illumination intensityVSUse of energy by stationary object

Solution Approach 1:

The patent segments the APL range into three zones with different brightness strategies. Only in the low APL zone (≤10%) does the system maintain peak brightness to preserve contrast. In the high APL zone (>50%), the system applies aggressive brightness reduction to minimize power consumption. This segmentation allows the system to optimize for contrast where needed and for power savings where possible.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent dynamically selects among three different light adjustment curves based on the current APL value. The system transitions from the first curve (peak brightness preservation) at low APL to the third curve (maximum power saving) at high APL. This dynamic adaptation allows the system to balance contrast and power consumption based on real-time content characteristics.

Inventive Principle:

Principle #15Dynamics

3Device complexity

If a single light adjustment curve is used for all APL values, then the adjustment method is simple, but display effect of HDR video becomes poor

Engineering Contradiction:

Improvebrightness adjustment complexityVSAvoiddisplay effect

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The patent divides the brightness adjustment into three distinct segments based on APL ranges: first light adjustment curve for APL≤10%, second light adjustment curve for 10%<APL≤50%, and third light adjustment curve for APL>50%. Each segment uses a different adjustment strategy optimized for its specific APL range, allowing contrast preservation at low APL while maintaining power efficiency at high APL.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent applies different light adjustment characteristics to different APL regions. At low APL (≤10%), the first light adjustment curve maintains peak brightness to preserve contrast. At intermediate APL (10%-50%), the second curve provides moderate adjustment. At high APL (>50%), the third curve applies stronger brightness reduction to save power. This localized optimization resolves the contradiction between contrast and power consumption.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS12142202B2Display brightness adjustment method and related apparatus

Publication Date: 2024.11.12 HUAWEI TECH CO LTD

AI summary

This application discloses a display brightness adjustment method, including: an electronic apparatus obtains a to-be-displayed image and calculates an average pixel level APL of the to-be-displayed image. The electronic apparatus determines, based on the third light adjustment curve, an actual display brightness value corresponding to the average pixel level of the to-be-displayed image. The electronic apparatus adjusts display brightness of the to-be-displayed image based on the actual display brightness value. In this way, impact exerted on contrast when brightness is turned down at a low APL can be ensured, and a high contrast effect of image brightness of an HDR display can be ensured.