Under-Screen Fingerprint Recognition With Local Brightness Control

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Solution Overview

Problem

High power consumption in fingerprint recognition of mobile terminals due to the need for high screen brightness, which reduces battery life.

Innovation Solution

Control the brightness of the touch area on the screen to a preset value for fingerprint authentication while keeping other areas at a lower brightness, using a fingerprint recognition module to collect and recognize fingerprint information.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the brightness of the entire screen is increased to improve fingerprint recognition rate, then the fingerprint recognition rate is improved, but the power consumption increases

Engineering Contradiction:
Improvefingerprint recognition rateVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies local quality by illuminating only the touch area (where the finger is placed) with high brightness while keeping other areas of the screen at lower brightness. This localized illumination approach ensures sufficient light for fingerprint recognition in the critical area while minimizing overall power consumption of the display screen.

Inventive Principle:
Principle #3Local quality

2Reliability

If the brightness of the entire screen is increased to improve fingerprint recognition rate, then the fingerprint recognition rate is improved, but the battery life is reduced

Engineering Contradiction:
Improvefingerprint recognition rateVSAvoidbattery life
Core Design Contradiction:
ReliabilityVSDuration of action of moving object

Solution Approach 1:

The patent implements local quality by controlling the display screen to provide high brightness only in the touch area where fingerprint recognition is needed, while other areas maintain lower brightness. This significantly reduces the total energy consumption of the display, thereby extending battery life while ensuring adequate illumination for accurate fingerprint recognition.

Inventive Principle:
Principle #3Local quality

3Use of energy by moving object

If the brightness of the touch area is controlled to a preset value for fingerprint authentication, then the power consumption is reduced, but the fingerprint recognition rate may be affected

Engineering Contradiction:
Improvepower consumptionVSAvoidfingerprint recognition rate
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

The patent applies parameter changes by dynamically adjusting the brightness parameter of the display screen based on the touch area detection. The system sets the brightness of the touch area to a preset value that is optimized for fingerprint recognition, ensuring sufficient illumination while minimizing power consumption. This parameter optimization resolves the contradiction between power savings and recognition accuracy.

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

Reduces power consumption and extends battery life while maintaining a high fingerprint recognition rate.

Implementation Method 1

light reflected by a fingerprint on a surface of the finger is received by an optical fingerprint sensor under the screen

Methodology Applied
Scientific EffectLight reflection: Reflection

Data Source

PatentEP3779738B1Fingerprint identification method and mobile terminal
Publication Date: 2025.08.06 VIVO MOBILE COMM CO LTD
  • EP3779738B1 patent drawingFigure 1
  • EP3779738B1 patent drawingFigure 2~3
  • EP3779738B1 patent drawingFigure 4

AI summary

A fingerprint recognition method and a mobile terminal are provided. The method includes: recognizing, if a touch operation on a screen of the mobile terminal is detected, a touch area, on which the touch operation is performed, of the screen of the mobile terminal (101); controlling, if it is detected that the mobile terminal is in a state for fingerprint authentication, a brightness value of the touch area to be greater than or equal to a first preset brightness value, and a brightness value of a display area other than the touch area of the screen of the mobile terminal to be less than the first preset brightness value (102); and collecting and recognizing fingerprint information of the touch area by using a fingerprint recognition module (103).