Patent ID: 11935319
Assignee: FINGERPRINT CARDS ANACATUM IP AB
Field: Measurement (Instruments)
Classification: CPC G  A | IPC G

Claim 0:
1. A method of evaluating a dielectric structure covering a plurality of sensing structures comprised in a fingerprint sensor and defining a finger receiving surface of the fingerprint sensor, the method comprising the steps of:
a) controlling the fingerprint sensor to change a potential difference between each sensing structure in a first set of sensing structures and each sensing structure in a second set of sensing structures, and to provide, for each sensing structure in the first set of sensing structures, a sensing signal indicative of a strength of a capacitive coupling between each sensing structure in the second set of sensing structures and the sensing structure in the first set of sensing structures;
b) controlling the fingerprint sensor to assign other sensing structures to the first set of sensing structures and the second set of sensing structures;
c) performing step a) and step b) until a respective sensing signal has been provided for each sensing structure in the plurality of sensing structures; and
d) providing an evaluation result for the dielectric structure covering the plurality of sensing structures based on the respective sensing signals provided for each sensing structure in the plurality of sensing structures.