A Polarized Imaging System For Multimodal Finger-Feature Acquisition

Recently, biometric technology has been drawing heavy attention for identity authentication. Although great achievements have been achieved, the unimodal-based biometric technology is still undesirable for robustly implementing personal identification in many real applications. So, the demand is great for accurate authentication in practice. In this aspect, multimodal biometrics has been verified to be superior to unimodal biometrics. Hence, multimodal-based biometric technology dominates in the biometrics community.By viewing the finger trait as the combination of a finger-vein, a finger-knuckle-print and a fingerprint, in this dissertation, an imaging system for finger-feature acquisition which lays the foundation for the multimodal finger-feature fusion has been designed. In this dissertation, the imaging feasibility is exploited firstly in simultaneously capturing finger-vein, fingerprint and finger-knuckle-print images. Second, based on the polarized imaging principle, a hardware device for multimodal finger-feature image imaging is designed. Finally, we design a software system using C++ language for implementing multimodal finger image acquisition.The polarized imaging system for finger-feature acquisition presented in this dissertation not only can capture finger-vein, fingerprints and finger-knuckle-print biometric images simultaneously but also has the following advantages: the locations of finger vein and finger-knuckle-print cameras can be adjusted automatically to make the ROI( Region-of-Interest) in the center of imaging plane, the multispectral light beams can be controlled when acquiring multispectral image, ant the polarized light can effectively reduce image noise.