摘要 |
<p>The present invention relates to a fingerprint sensor element, comprising a sensor electrode (11) formed in an upper conducting layer (M3), a lower electrode (17, 32) formed in a lower conducting layer (M2, P2) and at least one insulating layer (8, 9, 10, 22) between the upper conducting layer (M3) and the lower conducting layer (M2, P2). It further comprises a charge amplifier (13) having a negative (12) and a positive (14) input terminal and an output terminal (18). An upper side (11a) of the fingerprint sensor electrode (11) is arranged for facing a finger (5) and a lower side (11b) is arranged for facing the lower electrode (17), and the fingerprint sensor electrode (11) and the lower electrode (17) are arranged in such a way that a capacitance (Cref) is formed between them. The sensor electrode (11) is arranged for being connected to the negative input terminal (12) of the charge amplifier (13), and the lower electrode (17) is arranged for being connected to the output terminal (18) of the charge amplifier (13).</p> |