Fingerprints are categorized by three processes: According to the individual types of shapes and contours, the positions of various types on the finger are pointed out, and the number of ridges calculated by the rake and the ridges of the observation hopper are determined according to the relative size and size. Decision. The data obtained in this way is compiled into a concise table called personal fingerprint classification.
There are several variants of the Henry system, the one used by the FBI to recognize eight different types: positive, negative, double, ring, arc, tent-shaped arc, regular bucket, and accidental. type. The shape of the bucket is usually circular or spiral. The arc has a mound-like profile. The tent-shaped arc has a shape like a spike or a spire in its center. The corrugated pattern has some concentric U-turns or staples. The texture is referred to as "positive" or "anti-" to indicate the direction in which it is tilted; the anti-pan-tilt is slanted toward the thumb with respect to the direction of the little finger. The type accounts for about 65% of the entire fingerprint type; the bucket type accounts for about 30%, and the arc type and the tent-shaped arc add up to the other 5%. The most common type is antimony.