US 11,893,100 B2
Spoof detection based on specular and diffuse reflections
Johan Hammersberg, Floda (SE); Eric Setterberg, Västra Frölunda (SE); and Mattias Carlén, Gothenburg (SE)
Assigned to Fingerprint Cards Anacatum IP AB, Gothenburg (SE)
Appl. No. 17/917,780
Filed by Fingerprint Cards Anacatum IP AB, Gothenburg (SE)
PCT Filed Mar. 29, 2021, PCT No. PCT/SE2021/050280
§ 371(c)(1), (2) Date Oct. 7, 2022,
PCT Pub. No. WO2021/211030, PCT Pub. Date Oct. 21, 2021.
Claims priority of application No. 2050427-0 (SE), filed on Apr. 15, 2020.
Prior Publication US 2023/0267769 A1, Aug. 24, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G06F 21/32 (2013.01); G06V 10/145 (2022.01); G06V 40/13 (2022.01); G06V 40/12 (2022.01); G06V 10/56 (2022.01); G06V 10/82 (2022.01); G06V 10/50 (2022.01); G06V 10/147 (2022.01); G06V 40/40 (2022.01)
CPC G06F 21/32 (2013.01) [G06V 10/145 (2022.01); G06V 10/147 (2022.01); G06V 10/50 (2022.01); G06V 10/56 (2022.01); G06V 10/82 (2022.01); G06V 40/1318 (2022.01); G06V 40/1365 (2022.01); G06V 40/1382 (2022.01); G06V 40/1388 (2022.01); G06V 40/1394 (2022.01); G06V 40/45 (2022.01)] 20 Claims
OG exemplary drawing
 
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.