(a) The acquired human fingerprint image at 400 GHz and (b) the corresponding optical microscopy image.

(a) The acquired human fingerprint image at 400 GHz and (b) the corresponding optical microscopy image.

Contexts in source publication

Context 1
... in-vivo THz image of a human fingerprint acquired using our experiment setup is shown in Fig. 3a. Initially, a 3×2 mm area (40×30 pixels) is measured. In this image, the ridges and the valleys of the fingerprint can be clearly identified by the difference in the magnitude of the reflection coefficient. Several sweat ducts can be identified as dark spots in the image based on their THz absorption. In Fig. 3b the optical image of ...
Context 2
... our experiment setup is shown in Fig. 3a. Initially, a 3×2 mm area (40×30 pixels) is measured. In this image, the ridges and the valleys of the fingerprint can be clearly identified by the difference in the magnitude of the reflection coefficient. Several sweat ducts can be identified as dark spots in the image based on their THz absorption. In Fig. 3b the optical image of human fingerprint is given, verifying the imaging accuracy of the THz configuration. In the optical image, we can detect the small openings of the sweat ducts (sweat pores) as white spots on the ...

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