Fingerprint Collection Region Determination via Contact Area Stability

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current fingerprint identification technologies face issues in determining the correct fingerprint collection region, leading to incomplete fingerprint information due to misalignment between the gravity center of the contact region and the geometrical center, resulting in light leakage and reduced fingerprint data collection.

Innovation Solution

A method that determines the fingerprint collection region by calculating the change rate of feature parameters of the contact region, such as area and shape, to ensure the region coincides with the contact area, thereby activating the appropriate fingerprint identification sensors for complete data collection without light leakage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the fingerprint collection region is determined based on the gravity center of the contact region, then the fingerprint identification can be performed, but the collection region does not coincide with the contact area, resulting in incomplete fingerprint information and light leakage

Engineering Contradiction:
Improvefingerprint information completenessVSAvoidfingerprint data collection
Core Design Contradiction:
Measurement precisionVSLoss of information

Solution Approach 1:

The patent determines the contact region and its geometric center in advance before fingerprint collection begins. By pre-calculating the contact region boundaries based on touch signal data and determining the geometric center, the system prepares the accurate fingerprint collection region beforehand, ensuring complete fingerprint data collection without light leakage during the identification process

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent replaces the traditional gravity center calculation method with a geometric center calculation method based on contact region boundaries. Instead of using weighted average of touch signals (mechanical approach), the system uses geometric computation of the contact region polygon to determine the collection region center, achieving better alignment with the actual contact area

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Ease of manufacture

If a fixed radius circular region is used for fingerprint collection, then the implementation is simple, but the collection region does not match the actual contact area shape, leading to incomplete fingerprint data

Engineering Contradiction:
Improveimplementation simplicityVSAvoidfingerprint collection region accuracy
Core Design Contradiction:
Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent makes the fingerprint collection region dynamic by adjusting its boundaries based on the detected contact region. Instead of using a fixed radius circular region, the system dynamically determines the collection region shape and size to match the actual contact area, ensuring accurate fingerprint data collection while adapting to different contact scenarios

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the parameters of the fingerprint collection region (boundary coordinates, center position, shape) based on the detected contact region characteristics. By adjusting these parameters dynamically, the system achieves precise alignment between the collection region and contact area, improving fingerprint data completeness while maintaining implementation feasibility

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP3709147B1Method and apparatus for determining fingerprint collection region
Publication Date: 2022.03.02 BEIJING XIAOMI MOBILE SOFTWARE CO LTD
  • EP3709147B1 patent drawingFigure 1~2
  • EP3709147B1 patent drawingFigure 3~4
  • EP3709147B1 patent drawingFigure 5~6

AI summary

A method of determining a fingerprint collection region includes: determining a contact region according to a touch signal generated by a touch operation from a starting moment t0 of sensing the touch operation; determining a change rate of a feature parameter of the contact region; and determining the fingerprint collection region according to the contact region when the change rate is smaller than or equal to a preset change rate.