摘要 |
A fingerprint sensing device comprises an array of sense elements (12) which each include a sense electrode (33), providing in combination with an overlying fingerprint part a capacitance (35), and first and second diode devices (30, 31) connected respectively between the sense electrode and associated ones (18, 20) of first and second sets (e.g. row and column) address conductors. An address circuit (22, 24) connected to the address conductors biases the diode devices in a respective address period such that a potential is applied via the first address conductor and the first diode device to the sense electrode and thereafter stored charge, indicative of the capacitance, is transferred via the second diode device to the second address conductor. The device offers fast, reliable, scanning and can conveniently be implemented using thin film technology for low cost and compactness. |