公开(公告)号：US11301664B2

公开(公告)日：2022-04-12

申请号：US17273945

申请日：2018-09-12

Applicant: Fingerprint Cards AB

Inventor： Jun Liu ,  René Nilsson ,  Hans Martinsson ,  Ehsan Hashemi

IPC: G06K9/36 ,  G06K9/00 ,  G06K9/42

Abstract: The invention relates to a method of reconstructing a fingerprint image from a plurality of fingerprint subimages captured by an optical microlens array fingerprint sensor, and a sensor system performing the method. In an aspect, a method of reconstructing a fingerprint image from a plurality of fingerprint subimages captured by an optical microlens array fingerprint sensor arranged under a touch-display of a device is provided. The method comprises capturing an image of a fingerprint with the fingerprint sensor, extracting, from the captured fingerprint image, a fingerprint subimage for each microlens in the array, normalizing the corrected fingerprint subimages with corresponding subimages of a uniformity calibration image with known uniformity properties, rotating the normalized fingerprint subimages 180 degrees while maintaining their relative position with respect to the captured fingerprint image from which the fingerprint subimages are extracted, and combining the rotated and normalized fingerprint subimages into a fingerprint image.