Fingerprint recognition works on the principle of the uniqueness of ridge patterns, which are formed during embryonic development and remain unchanged throughout life. Each fingerprint is unique, allowing for reliable identity verification.
So how does your phone process a fingerprint?
Scanning the Fingerprint: When you place your finger on the sensor, the device scans the fingerprint graphically. There are different types of sensors:
- Optical sensors use light to capture an image of the fingerprint.
- Capacitive sensors measure the electrical capacitance between metal plates and the finger, which acts as one half of a capacitor.
- Pressure sensors use a non-conductive gel to measure the conductivity of the ridges pressed against it.
Fingerprint Analysis: After scanning, the orientation of the ridge patterns is analyzed, represented as line segments indicating the direction and trend of the ridges.
Ridge Extraction: The result is a black-and-white image of the fingerprint, where white areas represent the spaces between ridges and black areas represent the ridges themselves.
Ridge Thinning: To facilitate further processing, the ridges are thinned to preserve all crucial information.
Minutiae and Pattern Recognition: The phone identifies key features (minutiae) such as ridge endings or bifurcations and records their position and direction. It also recognizes the overall pattern of the fingerprint, which could be a loop, arch, or whorl.
Liveness Detection: The phone verifies that the finger is real and not a fake. It then compares the scanned fingerprint with the stored template. If they match, the phone unlocks.
If you are interested in developing an application, whether it uses fingerprint recognition or not, feel free to contact us.