The finger types are widely used in medical applications (FC mainly for pulse oximeters); the EC realization is often applied for vitality monitoring. In the PPG sensors working on the reflection principle, the IF/RD LEDs and the PHD measuring the intensity of the reflected light are placed ...
The principle of NFC is an electromagnetic induction that occurs between two coil-type inductors, and the induced power can be maximized by matching the resonance frequency of the two coils, which are included in the NFC device and NFC reader, respectively [23,29]. For stronger magnetic power...