How Fingerprint Scanning Works: Optical ScanningYou walk up to the door, clean off your thumb, place it on the door's new, futuristic fingerprint scanner and you open the door and walk through without a second thought. You have gotten used to it to the point that it has become as second nature to you as opening and closing your front door when you leave home for work. But have there been times when you thought about how fingerprint scanning actually works? If so, here are a few answers to your questions.
As you may know, fingerprints are very special identifiers unique to each person - even twins do not have the same fingerprints. The two most common fingerprint scanning techniques used are optical scanning and capacitance scanning. Optical scanning works in much the same way as digital cameras do. Using a charge coupled device (CCD), the optical scanner uses photosites that generate an electrical signal that respond to light. These photo sites record the light and dark pixels that make up the image of the fingerprint. Then a built-in device converts the signal into a digital image that the scanner can use to judge whether or not the fingerprint is valid.
Next time, we will discuss how capacitance scanning works.
by FingerTec USA