| 摘要 |
<p>This invention relates to a sensor module for measuring structures in a surface, especially in a finger surface being moved over the sensor module, comprising a number of sensor elements, and an outer electrode located aside the sensor elements, the sensor elements being coupled to at least one AC drive circuit providing a varying current or voltage, thus coupling a signal through the sensor elements to the outer electrode. The sensor elements are also coupled to an electronic circuit positioned on a substrate, said substrate comprising conductor leads coupling the sensor elements to the electronic circuit, and said electronic circuit being adapted to measure the magnitude of said capacitance or AC impedance.</p> |
