摘要 |
The fingerprint sensor transforms the fingerprint information of a finger under investigation into an electric output signal. The sensor incorporates a contact device or sensor plate of a piezoelectric material. This sensor plate has a contact surface. The finger exercises a contact pressure thereon and changes thereby the distribution of electric charges on the contact surface. The new charge distribution is in accordance with the fingerprint pattern of the finger. The sensor further incorporates an electric device which provides the electric output signal in accordance with the distribution of charges. |