# US 9,521,314 B2 · Fingerprint enrollment using elongated fingerprint sensor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,521,314 B2 - Document ID: US9521314B2 - Status: Granted - Kind: B2 - Application number: 14/833,890 - Filed: 2015-08-24 - Published: 2016-08-11 - Granted: 2016-12-13 - Earliest claimed: 2015-02-06 - Assignees: Fingerprint Cards AB - Applicants: Fingerprint Cards AB - Inventors: Eric Setterberg - Web page: https://patentgrep.com/patent/US9521314B2 ## CPC - G06V 40/1335: {Combining adjacent partial images (e.g. slices) to create a composite input or reference pattern; Tracking a sweeping finger movement} - G06V 40/50: Maintenance of biometric data or enrolment thereof - G06V 40/67: {by interactive indications to the user} - H04N 23/611: where the recognised objects include parts of the human body - G06V: IMAGE OR VIDEO RECOGNITION OR UNDERSTANDING - H04N: PICTORIAL COMMUNICATION, e.g. TELEVISION ## Abstract The present invention relates to a method of enrolling a fingerprint of a user's finger, by means of an elongated fingerprint sensor having a sensing area being smaller than the fingerprint. The method comprises the steps of instructing the user to place the finger on the fingerprint sensor with a first finger orientation for achieving a first angle between a longitudinal finger axis and a longitudinal sensor axis; acquiring a partial fingerprint image for the first orientation; instructing the user to place the finger on the fingerprint sensor with a second finger orientation for achieving a second angle; acquiring a partial fingerprint image for the second finger orientation; and forming a fingerprint enrollment representation for the finger based on the partial fingerprint images for the first and second finger orientations and a relation between the first angle and the second angle. ## Claims ### Claim 1 A method of enrolling a fingerprint of a user's finger having a longitudinal finger axis, by means of a fingerprint enrollment system comprising: an elongated fingerprint sensor for acquiring partial fingerprint images of said fingerprint, the fingerprint sensor having a sensing area being smaller than said fingerprint and having a longitudinal sensor axis; processing circuitry connected to said fingerprint sensor for forming a fingerprint enrollment representation for said finger based on a plurality of acquired partial fingerprint images; a memory; and a user communication interface for providing instructions to said user, said method comprising the steps of: instructing, through the user communication interface, the user to place said finger on the fingerprint sensor with a first finger orientation for achieving a first angle between said longitudinal finger axis and said longitudinal sensor axis; acquiring, using said fingerprint sensor, a partial fingerprint image for said first finger orientation; instructing, through the user communication interface, the user to place said finger on the fingerprint sensor with a second finger orientation for achieving a second angle, different from said first angle, between said longitudinal finger axis and said longitudinal sensor axis; acquiring, using said fingerprint sensor, a partial fingerprint image for said second finger orientation; forming, by said processing circuitry, the fingerprint enrollment representation for said finger based on the partial fingerprint images for said first and second finger orientations and a relation between said first angle and said second angle; and saving, by said processing circuitry, the fingerprint enrollment representation to said memory together with an identifier for said fingerprint to thereby enroll said fingerprint. ### Claim 2 (depends on 1) The method according to claim 1, wherein said second orientation is selected for said second angle to differ from first angle by at least 45°. ### Claim 3 (depends on 1) The method according to claim 1, further comprising the steps of: instructing, through the user communication interface, the user to place said finger on the fingerprint sensor with a third finger orientation for achieving a third angle, different from said second angle, between said longitudinal finger axis and said longitudinal sensor axis; and acquiring, using said fingerprint sensor, a partial fingerprint image for said third finger orientation, wherein said fingerprint template is additionally based on the partial fingerprint for said third finger orientation and a relation between said third angle and said second angle. ### Claim 4 (depends on 3) The method according to claim 3, wherein said third finger orientation substantially corresponds to said first finger orientation. ### Claim 5 (depends on 1) The method according to claim 1, wherein said steps of: instructing, through the user communication interface, the user to place said finger on the fingerprint sensor with a first finger orientation for achieving a first angle between said longitudinal finger axis and said longitudinal sensor axis; acquiring, using said fingerprint sensor, a partial fingerprint image for said first finger orientation; instructing, through the user communication interface, the user to place said finger on the fingerprint sensor with a second finger orientation for achieving a second angle, different from said first angle, between said longitudinal finger axis and said longitudinal sensor axis; and acquiring, using said fingerprint sensor, a partial fingerprint image for said second finger orientation, are repeated until it is determined, by said processing circuitry, that sufficient fingerprint information has been acquired. ### Claim 6 (depends on 5) The method according to claim 5, further comprising the steps of: determining, by said processing circuitry, a continuous area of said fingerprint jointly covered by said acquired partial fingerprint images; and determining, by said processing circuitry, that sufficient fingerprint information has been acquired when said continuous area is greater than a predefined area. ### Claim 7 A fingerprint enrollment system for enrolling a fingerprint of a user's finger having a longitudinal finger axis, said fingerprint enrollment system comprising: an elongated fingerprint sensor having a sensing area being smaller than said fingerprint and having a longitudinal sensor axis; a memory; a user communication interface; and processing circuitry connected to said fingerprint sensor, to said memory, and to said user communication interface for: controlling the user communication interface to provide an instruction to the user to place said finger on the fingerprint sensor with a first finger orientation for achieving a first angle between said longitudinal finger axis and said longitudinal sensor axis; controlling said fingerprint sensor to acquire a partial fingerprint image for said first finger orientation; controlling the user communication interface to provide an instruction to the user to place said finger on the fingerprint sensor with a second finger orientation for achieving a second angle, different from said first angle, between said longitudinal finger axis and said longitudinal sensor axis; controlling said fingerprint sensor to acquire a partial fingerprint image for said second finger orientation; determining a fingerprint enrollment representation for said finger based on the partial fingerprint images for said first and second finger orientations and a relation between said first angle and said second angle; and saving the fingerprint enrollment representation to said memory together with an identifier for said fingerprint to thereby enroll said fingerprint. ### Claim 8 (depends on 7) The fingerprint enrollment system according to claim 7, wherein a longitudinal extension of the sensing area of said fingerprint sensor is at least one and one half times a transversal extension of the sensing area of said fingerprint sensor.