Capacitive Fingerprint Scanner
Capacitive Fingerprint Scanner
This technology uses tiny intermediate capacitors to measure electrical changes on your fingerprints. When you place your finger on the scanner, ridges and valleys interrupt the electric field, creating a detailed map of your exact fingerprint. This approach provides improved security compared to optical scanners, making it popular for smartphones and applications that require high levels of security
Key features of this technology:
Electrical Detectives: The scanner surface is covered in a network of tiny capacitors, acting like miniature batteries that store electrical charge.
Fingerprint Interaction: When you place your finger on the scanner, the ridges (with better conductivity) come in contact with the capacitor plates, while valleys create air gaps.
Disrupted Electrical Field: This disrupts the electrical field around the capacitors. The varying conductivity of ridges and valleys affects the charge stored in different capacitors.
Building the Fingerprint Picture: By measuring these electrical variations across the capacitor grid, the scanner builds a highly detailed representation of your unique fingerprint.
Advantages of Capacitive Scanners:
Enhanced Security: Compared to optical scanners, capacitive scanners capture a more comprehensive fingerprint image, including details beyond just the ridges and valleys.
Scratch Resistant: The scanning surface is less susceptible to scratches or damage compared to optical scanners that rely on a clear light path for image capture.
Compact Design: The underlying technology allows for smaller scanner sizes, making them ideal for integrating into smartphones and other mobile devices.
Some Potential Drawbacks:
Moisture Sensitivity: Moisture or dryness on your fingers can sometimes affect scan accuracy.
Cost: Capacitive technology can be slightly more expensive to manufacture compared to optical scanners.