Capacitive fingerprint scanners use tiny capacitors to map your fingerprint by measuring the electrical charge differences created by ridges and valleys.
Here's a breakdown of how they work:
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Capacitors: A capacitive fingerprint scanner contains an array of tiny capacitors, each acting as a small electrical storage unit. Think of them as microscopic batteries.
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Finger Placement: When you place your finger on the scanner surface, the ridges of your fingerprint touch the surface directly, while the valleys remain slightly elevated.
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Charge Storage and Discharge: The capacitors underneath the ridges and valleys react differently due to the varying distances. Capacitors under ridges, being closer, discharge the electrical charge faster than capacitors under valleys.
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Mapping the Fingerprint: The scanner measures these differences in capacitance (electrical charge). The differences are then converted into a digital image of your fingerprint. Essentially, it maps the pattern of ridges and valleys based on their electrical characteristics.
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Generating an Image: An algorithm then uses this map to create an image of your fingerprint, which can then be compared to stored fingerprint data for identification or authentication.
In short, capacitive fingerprint scanners leverage the principles of electrical capacitance to differentiate between the ridges and valleys of your fingerprint, creating a unique digital map used for security and identification purposes.
