Single-sensor hand and footprint-based multimodal biometric ...

Box
Hole
(a) Employed scanning device.
Light
Lense
Mirrors
CCD-Sensor
moving direction
Cropped area
3.2 Proposed sensor
Flat platen surface
Pegs
Lense
Light
CCD-Sensor
(b) Zhang’s palmprint acquisition device.
Figure 3.3: Comparing (a) employed scanner-based sensor and (b) Zhang’s camera-based
palmprint capture device (see: Zhang [44]).
Finally, for minimising environmental light, the scanner is situated in a box with a round
hole at one end for hand insertion, see Figure 3.3(a). Footprint-based data acquisition may
also be supported using a box with a hole at the upper frontal edge, but has been executed
in a darkened environment without a box. It is clear to the author, that instant capture
devices, like Zhang’s palmprint acquisition sensor, for example, depicted in Figure 3.3(b)
have certain advantages over the proposed solution with respect to convenience, especially
in commercial proprietary solutions (e.g. when installed as an embedded authentication
system without needs for standardisation or inter-operability). Nevertheless, the proposed
approach will be shown to produce satisfying results at low cost.
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