Author: Hizana Farahath
Volunteer of AFRS
There are four types of fingerprints; they are: -
- Impressed prints
- Visible prints
- Plastic prints
- Latent prints
(1) Impressed prints: -
These prints have been pressed in a soft material such as the surface of a congealed pool of blood, sand, mud, or snow. A forensic expert may be able to capture impressed prints by photographing them or by casting a moulding. These prints are visible to the naked eye and are easily detected and photographed.
(2) Visible prints: -
These prints are easier to spot and these are made by fingers that have been in contact with wet paint, ink, blood. These prints are visible to the naked eye and are easily detected and photographed.
(3) Plastic prints:-
These prints are made by pressing on a material like soap, wax, or putty which retain the image of the fingertip ridges. They are three-dimensional depressions made by the friction ridges and are easily photographed.
(4) Latent prints: -
The prints are common types of prints. These prints are made when the natural oils and perspiration that exist between the fingertip ridges are transferred to a surface by touch. These prints are invisible and much harder to detect and preserve.
Fingerprint patterns
Different types of fingerprint patterns are
- Arch pattern: -
i. Plain arch:-
Ridges flow from one side of the pattern to the other with a rise or wave in the center. It has a smooth rise and gentle upward curve. It is the simplest of all fingerprint patterns.
ii. Tented arch:-
It has a central upthrust or a well-defined angle. It is regarded as a traditional pattern between arch and loop.
2. Loop pattern:-
A loop has one or more ridges that enter on one side, re – curve, and flow back out on the same side. The pattern has four characteristics; a core, a Delta, a recurving edge, a ridge count. Loops are subdivided into:
i. Ulnar loop:-
A fingerprint pattern that flows in the direction of the ulnar bone, towards the little finger.
ii. Radial bone:-
A fingerprint pattern that flows in the direction of the radial bone, towards the thumb.
3. Whorl pattern:-
Almost one–third of the population has ridge patterns. It looks like a whirlpool of ridgelines whorls are subdivided into 4 groups:-
i. Plain whorl:-
Two Delta’s at least one ridge that makes a complete circuit about the core. Some have concentric circles or ovals
ii. Double-loop Whorl:-
It consists of two separate loop formations, each with its core and two Delta’s.
iii. Central pocket loop Whorl:-
It is the combination of loop and whorl. It has all the characteristics of a loop, with the addition of a second Delta near the core.
iv. Accidental whorl:-
It is a pattern with two or more deltas that cannot be placed into any of the other classes.
v. Composite Whorl:-
It is composed of two or more separate patterns. It may look like a twinned loop.
Plain and rolled fingerprint
Plain fingerprint:-
Plain impressions are those in which the finger is pressed down on a flat surface but not rolled. While plain impressions cover a small area distortion introduction during rolling. Plain fingerprints are those in which the finger is pressed down on a flat surface but not rolled. The plain arch is the most simple of all fingerprint patterns and it is easily distinguished.
Rolled fingerprint:-
Rolled impressions are the ten fingers individually taken fingerprints images rolled from nail to nail. The plain impression is used to verify the sequence and accuracy of the rolled impression. When enrolling in an individual's fingerprints, it is crucial to capture the most accurate and highest capturing system being used to acquire the entire minutiae of the fingerprint.
