Why do people leave fingerprints.

The sweat glands in the skin of your finger tips produce a water based oil solution that coats the ridges of your print. These ridges retain a portion of this solution such that when the finger makes contact with a surface, a residue is left behind which is a facsimile of your print (i.e., laten print). It is this characteristic which gives Sense Technologies Inc.™ biometric devices the ability to electronically scan and analyze your print
 

Common Types of Fingerprints

Fingerprint patterns are divided into three main groups consisting of: Arches, Loops and Whorls. Approximately five percent of all fingerprints are Arches, 30% are Whorls and 65% are Loops.
 

Good Prints

Fingerprint scan quality can affect the reliability of any electronic fingerprint system. In general, automated fingerprint analysis systems work by creating a computer model of the live print scan. This model is based on many of the features found to be common in fingerprints and is sometimes referred to as a template. The process of creating this model/template is usually referred to as a 'Registration' process.

The process of matching a live print scan to a model/template is generally referred to as a 'Lookup'. The following are examples of GOOD print scans.

NOTE: CheckPrint T/A creates a computer model of your print which can only be used to verify against another live-scan of your print. It is not a facsimile nor can it under any circumstances be used to re-create a facsimile of your print.

Dry Prints

Due to a lack of natural moisture in the skin, a dry print can appear broken or incomplete to the electronic imaging system. This can result in inferior model construction during a registration process or inconsistent matching during a look-up process.

Dry skin can be caused by a multitude of climatic and environmental conditions. Handling materials or substances tend to absorb or wash the oils from the print. Items such as paper, cloth, wood or chemicals (i.e., acetones, thinners, cleaning agents etc.) will have a direct result on the dryness of your fingers. These items tend to absorb or wash oils from the skin leaving the ridges void of the necessary moisture to reliably electronically image the print.

To regenerate these natural oils, the tips of your fingers can be rubbed together or against the palm of your hand. In most climatic and environmental conditions the bridge of your nose and forehead tend to retain their natural oil.

Wet Prints

Excessive moisture in the skin can cause line-type features in the print to blend together during the registration or look-up process resulting in inferior model constructs or inconsistend look-ups. An excessively wet print is analogous to viewing a painting after a puddle of paint has been poured on it (you can't see the features through the puddle). Excessive moisture is generally caused by sweating or handling wet materials or substances. Common sources are greasy foods (i.e., french fries), hand lotion or makeup. The condition is easily solved by removing the excess moisture.