Patent ID: 11893100
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 color 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, wherein the image portions comprise:
one or more first image portions of a first type being captured by pixels in the photodetector pixel array arranged directly under a light source being active during image acquisition to capture predominantly specular light reflected off the object, and
one or more second image portions of a second type being captured by pixels in the photodetector pixel array arranged under an at least partly in-active illumination area of the color controllable light source during image acquisition to capture predominantly diffuse light reflected off the object;

identifying the one or more first image portions in the acquired image and extracting first metrics from the one or more first image portions;
identifying the one or more second image portions in the acquired image and extracting second metrics from the one or more second image portions; and
performing biometric authentication including spoof detection based on the first metrics and the second metrics.