Biometric Modality
- Fingerprint
- What are slap fingerprints (slaps)?
- How many fingerprints are best?
- Are fingerprints inherited? Are they more similar between family members than between strangers?
- Can children’s fingerprints be collected?
- What is a “latent fingerprint”?
- If a latent print is acquired, can it be used to access a biometric system?
- Iris/Retina
- Face
- Other
Fingerprint
What are slap fingerprints (slaps)?
Slaps are fingerprints taken by simultaneously pressing the four fingers of one hand onto a scanner or a fingerprint card. Slaps are known as four finger simultaneous plain impressions.
How many fingerprints are best?
The number of fingerprints required is application dependent based on the implementation details. While a single fingerprint might prove sufficiently accurate for certain applications, two fingerprints may be required for increased levels of accuracy. In general, ten rolled fingerprints will always have the potential for the highest accuracy, but they take much more time to gather with the current capture technology.
Are fingerprints inherited? Are they more similar between family members than between strangers?
Close relatives may have similar patterns, such as loops, whorls, or arches. This information is typically not used directly for recognition. The minutiae pattern, which is used for recognition, is not inherited or similar; this characteristic even differs between an individual’s own fingers and the fingers of identical twins.
Can children’s fingerprints be collected?
Yes, in most cases, a child’s fingerprints can be collected after the age of one year or so, but the prints may not have the clarity of adult prints. It is not clear whether fingerprints taken from children can be automatically matched to those same individuals later as adults.
What is a “latent fingerprint”?
A latent fingerprint is a fingerprint “image” left on a surface that was touched by an individual. The transferred impression is left by the surface contact with the friction ridges, usually caused by the oily residues produced by the sweat glands in the finger.
If a latent print is acquired, can it be used to access a biometric system?
Theoretically, yes, some latent prints could potentially be used to gain access to a system implementing biometrics, but it is not a practical or cost-effective approach in most applications. There are easier ways to break into a system. Many systems are implementing liveness detection to prevent attacks such as this from occurring.
Iris/Retina
What is the difference between iris and retina recognition?
Iris recognition uses the unique patterns in the individual’s iris, a muscle that is the colored portion on the front of the eye. Retinal recognition uses the unique pattern of blood vessels on an individual’s retina at the back of the eye.
Source: http://www.stlukeseye.com/Anatomy.asp
Is iris or retina recognition dangerous to the eye?
Iris and retina recognition involve capturing a high quality picture of the iris or retina, using a digital camera. In the acquisition of these images, some form of illumination is necessary. Iris uses near infrared light, which is believed to be safe. Although retina technology is not currently available, previous technology involved the illumination of the retina using infrared and visible light. Literature is inconclusive on the long-term effects of repetitive exposure to this illumination.
Does iris or retina recognition use a laser?
No, neither iris nor retinal recognition makes use of a laser. Both techniques use some form of illumination, but these techniques are not lasers as the term is commonly understood.
What is the impact of contact lenses on iris recognition systems?
Typically, contacts do not affect the performance of the system, although some color changing and patterned contacts haven proven to be an issue. Also, some issues have occurred in the recognition of individuals wearing hard gas permeable contacts.
Can iris recognition be used for identification purposes?
Yes, it is possible to use iris for identification.
Face
What effects will facial expressions, hairstyle, glasses, hats, makeup, etc. have on face recognition systems?
Minor variances, such as those mentioned, will have a moderate impact on a face recognition system, decreasing its ability to recognize faces. The proposed ISO standard for facial recognition (ISO 19794-5) requires the removal of dark glasses and hats, movement of the hair away from the eyes, and recommends a neutral facial expression. Anything that sufficiently obscures the primary face region will have a negative impact on the recognition system.
Other
What is the difference between speech and speaker recognition?
Speech recognition is the identification of the words being said, and is not a biometric technology. Speaker recognition (sometimes referred to as voice recognition) recognizes the speaker, not the words. Speaker recognition is a biometric technology.
Is speaker recognition language/word independent?
Word independent speaker recognition systems are available and can be used in any language. Whether or not speakers can be recognized if they change languages is the subject of current testing.
What is a behavioral biometric?
A behavioral biometric is one based on an individual's unique actions and is captured over a period of time. Examples are gait (the way an individual walks), keystroke dynamics, and signature dynamics.
Is DNA a biometric?
There is not universal agreement on this issue. At this point, DNA recognition is not performed by an automated method, and is therefore not considered a biometric; however, it may be at some point in the future.
Is Radio Frequency Identification (RFID) a biometric?
No, RFID is a technology that may be integrated with biometrics. Unlike biometrics, RFID systems are not biologically tied to an individual. RFID is a technology that stores and retrieves data remotely through devices called RFID tags or transponders. These devices use radio frequency (RF) signals to exchange information. They contain antennas that allow them to respond to queries from RFID transceivers. Some examples of RFID tags include sensors in library books, E-PASS Toll Collectors, and building access control cards.