Patent ID: 11900715
Assignee: FINGERPRINT CARDS ANACATUM IP AB
Field: Computer technology (Electrical engineering)
Classification: CPC G  H | IPC G

Claim 0:
1. A method for biometric authentication using an optical biometric arrangement comprising an image sensor comprising a photodetector pixel array configured to capture an image of an object, the image sensor being arranged under a controllable light source comprising light source units, the method comprising:
providing a light pattern comprising portions of different light intensity for illuminating the object;
acquiring an image of the object, the image comprising image portions corresponding to the portions of different light intensity of the light pattern illuminating the object,
at least one image portion of a first type being captured by pixels in the photodetector pixel array configured to capture light of a first distinguishable color and arranged directly under a light source unit being active during image acquisition to capture predominantly specular light reflected off the object, and
at least one image portion of a second type being captured by pixels in the photodetector pixel array configured to capture light of a second distinguishable color and arranged under an at least partly in-active illumination area of the controllable light source during image acquisition to capture predominantly diffuse light reflected off the object, and
performing biometric authentication including spoof detection based on metrics extracted from the image portions of both the first type and the second type.