Types of Fingerprint Patterns

What are Different Types of  Fingerprint Patterns?

1. Arches

Arches are found in approx 5% of the recorded fingerprints. In an Arch pattern, ridges enter from one side travel to the other side, and lift slightly at the center of the pattern (like a wave) finally exiting from the opposite side. 

Based on the nature of Arches they are further divided into two types i.e. Plain Arch and Tented Arch.

(a) Plain Arches

Plain Arch is the simplest pattern among all fingerprint patterns. In a plain arch, the ridges enter from a side (say left) and flow to the opposite side (Right) by making a small rise at the center like a wave. They don't have any core deltas but they do have numerous ridge formations like ridge endings, bifurcations, dots, and islands.

(b) Tented Arches

In this type of Arch, most of the ridges enter from one side and flow towards the opposite side by making a definitive angle (90 degrees or less) or standing straight at the center of the pattern and finally exiting from the opposite side. They also don't have any core or deltas but they do have numerous ridge formations like ridge endings, bifurcations, dots, and islands.

2. Loops

Around 60-65% of the recorded fingerprints are loop which makes it the most common fingerprint pattern in the population. A loop is formed when one or more ridges enter from a side (either left or right), continuing up to the center of the pattern, recurving around the core forming a loop, and then flowing back and terminating/exiting from the same side of the pattern. 

A loop always has one delta and a core and at least one ridge passes freely between the delta and the core. Based on the direction of opening and closing the loops, they are further subdivided into two types:

(a) Radial Loops

The loop is formed by the ridges entering from one side and flowing back from the same side after recurving around the core, to the same side with the opening of the loop pointing toward the radial bone or 

(b) Ulnar Loop

This loop is also formed by ridges, which enter from one side and flow back, after recurving around the core, to the same side with the opening of the loop pointing towards the ulnar bone or the little finger of the same hand. To check whether the loop is radial or ulnar, we must know the hand from which the fingerprint originated.

3. Whorls

Whorl is found in the approx 30-35% of the recorded fingerprints of the population, making it the second most common fingerprint pattern after the loops. In a whorl, the ridge enters from a side making a complete spiral around the core of the fingerprint and terminate or tend to terminate at the core. 

A whorl has 2 deltas and one core and the imaginary line drawn between two deltas must cross at least one recurving ridge to call the pattern a whorl. These types of whorls are known as plain whorls.

4. Composites

Composites are the 4th category of the fingerprint pattern. They are a mixture of Arches, loops, and Whorls. Around 1-2% of the population have these composites. Based on the nature of ridge movements, composites are classified into 4 types:

(a) Central Pocket Loops

A central Pocket loop is a combination of a loop and a whorl. In this fingerprint pattern, most of the ridges form loop, but one or more ridges recurve around the core, forming a pocket. If an imaginary line is drawn between two deltas then it should not intersect any of these recurving ridges.

(b) Double/ Twinned Loops

As the name suggests, a twinned loop contains a double-loop pattern. The two loops either overlap or surround each other and contain the point of the core exiting towards the different delta. The double loop pattern is sometimes referred to as the "Ying-Yang" symbol.

(c) Lateral Pocket Loops

A lateral pocket loop is also a double loop pattern that is formed by two loops overlapping or surrounding each other. In this fingerprint pattern, two different kinds of loops enter from the same end of the finger, recurve, and exit from the same end, one loop forms a covering-like pocket outside the other loop.

(d) Accidental

Accidental patterns are formed with the combination of two different fingerprint patterns except for plain arch. They have 2 or more deltas. They are too irregular to be placed under the above 3 categories.