FAQS

 
FAQs - Fingerprints

What is the difference between verification and identification?
Verification means that the system checks whether a person is who he claims to be. This implies that the identity of the respective person has been provided to the system prior to the verification. This could, for example, be done by entering the user ID, as in iGuard FPS110. Identification implies that a system checks whether the individual is known (and legitimate) by comparing the individual's biometrics features to all persons known to the system.

What are minutiae?
Minutiae are unique points of a fingerprint. The relative position of minutiae is different for each individual. Even twins have different minutiae constellations and different fingerprints.

How many minutiae are needed for comparison?
A complete fingerprint is made up of up to 100 minutiae. The Veridicom sensor that iGuard FPS110 uses usually delivers about 20 to 30. Note that European courts accept 12 minutiae matches for a positive, unambiguous identification.

How do bruises or cuts on fingers affect accuracy?
Medical tests show that when damage to a finger's skin surface heals, the skin is quickly restored to normal with the same patterns as before. If the injury causes a deep scar, it might be necessary to enroll a new reference image so that the new fingerprint image also resides in the system's reference data.

What about people who are rough on their hands?
People in professions that are rough on the hands (such as construction workers) may not leave optimal fingerprint images. This problem is generally solved by repeated verification. Also, iGuard FPS110's security level can be adjusted. Another way to reduce "false rejection rates" is to use more than one reference image of the same finger. This enhances the recognition process's reliability.

What about dry finger / wet finger issues?
Dry finger is the condition of some users that have dry skin, which almost always makes for a light and broken image, and consequently reduced identification. While other optical sensors often coat the optic with silicone to make up for the problem (which can be wear out easily), iGuard FPS110 uses the DFX software technology (developed by Veridicom) to reduce the effects of the problem. To further improve the performance, users can rub their fingers against their noise or forehead, increase their finger pressure, or use hand cream to minimize the problem. Wet finger is the opposite of dry finger and occurs from wet hands, too much hand cream, or extremely supple skin. Ridges will squash and seem to merge in the image, or the image could become totally black. Hand washing and less pressure can alleviate this problem.



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