Fingerprint enrollment using touch sensor data

Patent metadata

Field	Value
Publication number	US-2016180145-A1
Application number	US-201514833809-A
Country	US
Kind code	A1
Filing date	Aug 24, 2015
Priority date	Dec 18, 2014
Publication date	Jun 23, 2016
Grant date	—

Abstract

The present invention relates to a method of enrolling a fingerprint of a user's finger, by means of an electronic device comprising a touch sensor having an active area corresponding to a first surface portion of the electronic device; and a fingerprint sensor having an active area corresponding to a second surface portion of the electronic device. The comprises the steps of acquiring a touch sensor signal indicative of a sub-area of the touch sensor being touched by the finger; acquiring a partial fingerprint image of a portion of the fingerprint; a positional relationship between the portion of the fingerprint and the finger based on the sub-area and a positional relationship between the first and second surface portions of the electronic device; and forming a fingerprint template based on acquired partial fingerprint images and the determined positional relationships.

First claim

1 . A method of enrolling a fingerprint of a user's finger, by means of an electronic device comprising:
a touch sensor for touch-based control of said electronic device, said touch sensor having an active area corresponding to a first surface portion of said electronic device; and a fingerprint sensor having an active area corresponding to a second surface portion of said electronic device, said method comprising the steps of:
a) acquiring, from said touch sensor, for each finger placement in a sequence of finger placements on said fingerprint sensor, a touch sensor signal indicative of a sub-area of said touch sensor being touched by said finger;
b) acquiring, from said fingerprint sensor, for each finger placement in said sequence of finger placements on said fingerprint sensor, a partial fingerprint image of a portion of said fingerprint;
c) determining, for each finger placement in said sequence of finger placements on said fingerprint sensor, a positional relationship between said portion of the fingerprint and said finger based on said sub-area and a positional relationship between said first and second surface portions of the electronic device;
d) forming a fingerprint template based on said acquired partial fingerprint images and said determined positional relationships; and
e) saving said fingerprint template together with an identifier for said fingerprint to thereby enroll said fingerprint.

2 . The method according to claim 1 , further comprising the step of:
f) determining a total coverage of said fingerprint by said portions of said fingerprint imaged in said sequence of finger placements.

3 . The method according to claim 2 , wherein steps a) to c) are repeated until said determined total coverage exceeds a threshold coverage.

4 . The method according to claim 3 , further comprising the step of:
g) determining said threshold coverage based on at least one acquired touch sensor signal.

5 . The method according to claim 4 , wherein step g) comprises the steps of:
g1) determining at least one dimension of said finger based on said at least one acquired touch sensor signal; and g2) determining said threshold coverage based on said at least one dimension.

6 . The method according to claim 1 , wherein step a) and step b) are performed substantially concurrently.

7 . The method according to claim 1 , further comprising the step of:
h) prompting, prior to step a), for each finger placement in said sequence of finger placements, said user to place said finger on the fingerprint sensor.

8 . The method according to claim 1 , wherein step c) comprises determining a finger contour based on said sub-area.

9 . The method according to claim 1 , further comprising the step of:
i) extracting, prior to step d), for each finger placement in said sequence of finger placements on said fingerprint sensor, template data from said partial fingerprint image.

10 . An electronic device comprising:
a touch sensor for touch-based control of said electronic device, said touch sensor having an active area corresponding to a first surface portion of said electronic device; a fingerprint sensor having an active area corresponding to a second surface portion of said electronic device; a user interface; a memory; and processing circuitry connected to said touch sensor, said fingerprint sensor, said user interface, and said memory for:
acquiring, from said touch sensor, for each finger placement in a sequence of finger placements on said fingerprint sensor, a touch sensor signal indicative of a sub-area of said touch sensor being touched by said finger;
acquiring, from said fingerprint sensor, for each finger placement in said sequence of finger placements on said fingerprint sensor, a partial fingerprint image of a portion of said fingerprint;
determining, for each finger placement in said sequence of finger placements on said fingerprint sensor, a positional relationship between said portion of the fingerprint and said finger based on said sub-area and a positional relationship between said first and second surface portions of the electronic device;
forming a fingerprint template based on said acquired partial fingerprint images and said determined positional relationships; and
saving, in said memory, said fingerprint template together with an identifier for said fingerprint to thereby enroll said fingerprint.

11 . The electronic device according to claim 10 , wherein said touch sensor and said user interface are constituted by a touch display.

12 . The electronic device according to claim 10 , wherein said second surface portion is adjacent to said first surface portion.

Assignees

• Fingerprint Cards Ab

Inventors

• Setterberg Eric
• Sarvé Hamid
• Tingdahl David

Classifications

• G06V40/1365

  Matching; Classification · CPC title

• G06V40/1335 Primary

  Combining adjacent partial images (e.g. slices) to create a composite input or reference pattern; Tracking a sweeping finger movement · CPC title

• G06F21/32

  using biometric data, e.g. fingerprints, iris scans or voiceprints · CPC title

• G06F3/03547

  Touch pads, in which fingers can move on a surface · CPC title

• G06K9/00087 Primary

  Physics · mapped topic