The varieties of papillary patterns should be attributed. The secrets of patterns on the fingers: how to determine the sign of the Zodiac by fingerprints? Types and types of papillary patterns

02/15/2016 11/14/2016 by [email protected]

Fingerprints are the science of dermatoglyphics. This article will outline the most basic elements that you should pay attention to. In order not to overload with information, let's assume that most of the readers understand the patterns on the fingertips and take into account the main three types: loops, arcs, curls. There are also mixed types, hip arches, but they are rare and usually occur on only one finger.

Where to begin?

It is not necessary to take a fingerprint by fingerprinting. You can use any dark glossy surface, such as a phone case or a magazine. But even that is not necessary. With sufficient light, prints can be seen with the naked eye. Take the person's hands and examine each finger. You need to discover the quantitative advantage of a particular print pattern. Then examine the other hand, determine which hand has more certain prints. Then you need to determine the maximum number of prints from two hands. So we find out who the person is: looper, arc or curl. It may be difficult to recognize some patterns, here you just need to remember the so-called "deltas" (also called "triradii"). They are present only on curls (two deltas) and loops (one delta).

We figured out and determined the type and number of patterns.

It is also worth knowing whether a right-handed or left-handed person is of particular importance. If a person is right-handed and has three arcs on his left hand, and three loops on his right, then all attention should be paid to the qualities that the loops give. And the variety of patterns on the fingers speaks of the adaptability of a person.

What can be said about a person with a predominant loop pattern?

Loops are a common type of pattern for Europeans. Most loops speak of a calm, balanced character. Such people are responsive and always try to help others. In education, the “loopers”, both in school years and in higher educational institutions, are not excellent students. Usually they are good students or close to excellent students. They are very punctual and responsible, but they do not show initiative. Sociable, easy to make friends.

A wonderful interlocutor is indicated by loops on the index fingers of both hands. They are very sociable and always work as a team. Curious and efficient. Such people get sensations and information exclusively from communication with other people. Strict logic is not observed in people with loops, they are highly dependent on the opinions of others. And for the sake of the society with which they are in contact, they can change their minds. In a difficult period of life, they need only communication with people. They are emotionally predictable, expressive and open. Manner is soft, speech is easy, walking is smooth, relaxed. With a variety of gestures, facial expressions in such people correspond to internal experiences. They are distinguished by good or excellent health, although in childhood they can get sick very often, but in adulthood they can endure any cold or illness without any problems. They belong to the category of long-livers. People with loops can be encouraged to run and swim, based on their physical abilities, they can excel in these sports. By temperament, a person with loops is a sanguine person. They do not tolerate boring and monotonous work that is not interesting to them. The owners of the loops are very touchy, but easygoing. However, this sign is seen with the predominance of loops on the right hand. There are also unfriendly signs - radial loops (tilted towards the thumb), which indicate a tendency to epilepsy. In married life, they can be unfaithful. If there are ten loops on the hands, then this indicates a highly developed fantasy, they say about such people - not from this world. The person is out of touch with reality.

Curls are most often observed on the fingers of the right hand, mainly on the index and ring fingers. People with the most curls are quick-tempered but easy-going. They are gifted creatively, grasp everything on the fly, learn quickly, analyze any events.

They start several things at once, but often do not finish them and lose interest in them. A large number of curls also indicates an easily excitable unstable psyche, prone to depression. The greater the number of curls, the more a person is closed, thinks a lot, strives for solitude and soul-searching. He draws sensations from within himself, and information from written sources. Strict logic in thinking and exactingness in evidence. It is difficult to convince, to change an already chosen thought. They are constantly dissatisfied with themselves and doubt everything. They are usually insecure, indecisive. Such a person is easily hurt. In difficult times, he needs solitude. Emotionally unpredictable, hides his feelings and experiences. If a person has 10 curls, then we can say that he is lazy and likes to watch what is happening from the side.

Most curls speak of a distrustful character. People with curls are good at making friends, so they don't have many friends. Others they simply consider familiar. Short temper and quickness are characteristic with more curls on the right hand. If there are more curls on the left hand, then such a person is very touchy, but he will keep the insult to himself for a long time.

At a certain time, under the influence of various factors, for example, in a state of intoxication, a person with “left” loops will remember everything that he has accumulated on you and tell you everything he thinks. You will learn a lot about yourself and about the person who tells you all the details accumulated about you.

By temperament, a person with curls is a phlegmatic person. His speech is inexpressive and slow. The voice is quiet. There is a lethargy of gait, clumsiness of movements, angular postures. Gesticulation is either absent or restrained. Facial expressions are weak, inexpressive, her self-control is high. If there are curls on the index fingers of the left and right hands, then such a person is a born thinker. People with a lot of curls have a predisposition towards programming, law, scientific work, but a tendency to become a sexual homicidal maniac has also been seen.

People with curls have a variety of complex behaviors, they do not know what they are capable of. They are very hardy, but they cannot endure unpleasant circumstances for themselves and test their endurance. If curls are present on the thumb, index and middle fingers, this indicates that the person has good vocal abilities. Usually such people can be recommended playing the guitar and singing. They also have good coordination of movements, so it is worth offering these people martial arts such as wrestling or boxing. In football, basketball, the role of a defender is more suitable for them. If there is a funnel, a ringlet (annular curl) in the curl, then this indicates that this person is interested in mysticism, psychology, parapsychology, philosophy and other secrets of being.

The presence of most arcs on the hand makes a person energetic, self-confident. Usually he is more open and simple in making decisions and his actions. Such a person has confidence in everything: in posture, gait, manners, gestures. He has an expressive artistic expression.

Most of the arcs speak of a person who always and everywhere considers himself a bearer of truth. It is impossible to convince him and force him to admit he was wrong, he defends any decision made to the end. Such people have a purely concrete thinking. They are unambiguous and purposeful. It is difficult for them to adapt to changes in the surrounding space and listen to the opinions of other people. They usually overwhelm those around them with their emotional incontinence. We can say that they have an average degree of predictability of emotional experiences. The speech of such a person is slightly muffled, but quite sonorous, the phrases are sharp and clear. Feelings are drawn exclusively from practical actions. However, to solve the tasks, he often prefers to involve other people.

Arcs speak of a truthful, outspoken person. He is traditional, responsible, honest, inclined to obey. Appreciates simple things and pleasures, but can be inflexible, bossy and proud. Loves and appreciates music and art. By temperament, a person with arcs is a choleric. In a difficult moment, he should be busy with something, do something, that is, distract himself with any practical actions. He does not tolerate “tenderness” in relationships, but they are very devoted and will never leave their own. Until the age of thirty, he can succeed in sports such as athletics, cycling, football, basketball, volleyball. Moreover, in sports it is desirable to be an attacker. "Dugoviki" do not tolerate long journeys and heat. However, their health is rather fragile, and after thirty-five years hypertension and angina pectoris appear.

The wide possibilities of fingerprinting in relation to the detection and investigation of crimes are explained by the structural features and properties of the skin of the palmar surface of the hands and feet of a person.
In these areas, the skin has a papillary pattern - a complex relief pattern formed by alternating rollers (0.1 - 0.4 mm high, 0.2 - 0.7 mm wide) and grooves - depressions (0.1 - 0.3 mm wide ).
The main properties of papillary patterns that allow them to be used for personal identification purposes are individuality and relative variability.

Individuality (uniqueness)- the presence in each individual pattern of a set of well-defined features of the structure, making it unique in other patterns.

A feature of the individuality of the papillary pattern is that it is a huge information array, the combination of elements of which in a complete fingerprint of a hand can theoretically be repeated once in 10 40 - 10 50 prints. This allows using only 7-10% of the area of the pattern of the nail phalanx of the finger when identifying a person only by the structural features of the papillary pattern.

Relative immutability- preservation of the structure of the papillary pattern in an unchanged state over time:

own stability - formed in the third or fourth month of intrauterine life, the pattern remains unchanged throughout a person's life, up to the complete destruction of the soft tissues of the corpse;

pattern resistance to deformation - at the time of trace formation, the skin, due to its elasticity and elasticity, retains the identification ability of prints, regardless of the degree of their deformation. The inherent stability of the papillary pattern is provided by the regenerative ability of the main layer of the epidermis of the skin.

Rice. 1. The structure of the skin of the palms of the hands and soles of the human feet:

I - epidermis; II - dermis; III - subcutaneous fatty tissue; 1 - stratum corneum of the epidermis; 2 - germ layer of the epidermis; 3 - papillary layer of the dermis with sensitive bodies; 4 - nerve endings; 5- duct of the sweat gland; 6 - sweat gland; 7 - the mouth of the sweat gland (time)

Rice. 2. Incision of the skin of the finger:

the epidermis is partially separated from the dermis; each paired row of papillae (A) corresponds to a papillary line (B)

Leather consists of two main layers (Fig. I):

top - epidermis, or cuticle (from Greek epi - over, over), which has a multilayer structure and mainly has a protective function;

lower - dermis (from the Greek derma - skin), which performs vital physiological functions (supporting, mechanical, tactile).

The main role in the formation of the papillary pattern is played by the papillary layer (from the Latin papilla - papilla) of the upper part of the dermis. The papillae, located in paired rows 0.15 mm high (the largest - up to 0.2 mm), are separated from the adjacent row by recesses. On the surface of the nail phalanges of the fingers, there are more than 100 of them per square centimeter (on the lower leg - only 9-10). The epidermis, elastically covering the paired row of papillae, exactly copies them and forms a papillary line, and in the place of depressions - interpapillary spaces, thereby creating a complex and unique pattern (Fig. 2).

The thickness of the epidermis is 0.07 - 2.5 mm; the thickest layer (1.5 - 2.5 mm) - on the palms and feet. The upper (horny) layer of the epidermis is completely renewed within 7-11 days.

The main (lower) layer of the epidermis consists of living cells, which, multiplying (dividing), ensure the displacement of dying ones and the regeneration (regeneration) of the papillary pattern. This layer is otherwise called sprout, or malpighian - thanks to it, the epidermis of the skin of the palms and feet is completely renewed in about 20 days.

The individuality of the external structure of the papillary pattern favorably distinguishes the objects of fingerprint examination among others, including the objects of trace studies:

displays of papillary patterns are distinct, easily detected and accessible for visual observation using simple technical means;

despite the variety of features of the external structure of the pattern, they lend themselves to a clear and simple classification, which ensures the process of their individualization and distinction;

the multiplicity of features makes it possible to carry out identification using a combination of features displayed in traces that are insignificant in area.

The main role in the ability of the papillary pattern to display its features in colorless traces is played by trace substance, the main components of which are sweat and fat.

Human skin has about 2.5 million sweat glands (pores), which during the day form up to 500-600 ml of sweat, providing metabolism and body heat regulation. On the palmar surface there are from 370 to 1000 sweat glands (on the sole of the foot - up to 360, on the lower leg - no more than 70). According to the composition of the secreted sweat and size, the sweat glands are divided into large (apocrine) and small (melocrylic). Large ones are located on separate areas of the skin (on the forehead, in the armpits, etc.), small ones - all over the skin.

The human body in a calm state emits sweat impulsively, at intervals of about 15 minutes; sweat accumulates in the recesses of the pores, from where it subsequently evaporates.

The sweat glands are located in the subcutaneous adipose tissue, and their excretory corkscrew-shaped ducts, passing through the dermis, end in the upper layer of the epidermis with funnel-shaped mouth openings - pores. The largest number of small pores is located in the grooves between the papillary lines. The frequency of occurrence and the nature of the severity of the pores, as a rule, is greater in the central part of the papillary pattern of the fingers than in the peripheral areas.

The chemical composition of sweat and the ratio of its components depend on the degree of perspiration of the body, the intensity of metabolism, human health, his emotional and physical condition. Sweat consists of water (97.7 - 99.6%), as well as inorganic and organic compounds:

Inorganic components (mg):	Nitrogen-containing compounds (mg):
Chlorine 36 - 995	Total nitrogen 66 - 108
Sodium 17 - 400	Non-protein nitrogen 17 - 196
Potassium 7 - 400	Nitrogen amino acids 1 - 10.2
Calcium 0.3 - 11.8	Ammonia nitrogen 1 - 35
Magnesium 0.02 - 4.5	Urea nitrogen 7.5 - 128.0
Phosphorus Traces - 7.37	Uric acid nitrogen 0.2 - 1.2
Iodine 0.0007 - 0.00095	Creatinine nitrogen 0.11 - 8.6
Copper 0.006
Manganese 0.006
Iron 0.024 - 0.064

In addition to sweat, the composition of the trace-forming substance of the papillary pattern includes neutral sebum and the smallest cells of dead epidermis. During a lifetime, a person loses an average of 18 kg of keratinized epidermal cells. Skin areas with a papillary pattern do not have sebaceous glands, and fat gets on them from other areas of the skin upon contact, and therefore the amount of fat on the pattern strongly depends on the "greasiness" of the skin and the frequency of contact with it (a person's sebaceous glands secrete about 20 g of sebum, intended to lubricate the hair and skin surface).

The trace-forming substance is commonly called sweat fat. The components of the sweat-fat substance play a crucial role in the process of detecting (identifying) handprints by physical and chemical methods.

It is known that the relief of the skin is not the same. On the palms (feet of the legs), in addition to ridge-like protrusions called papillary lines and separated by grooves, there are flexor (flexion) lines, wrinkles and folds (white lines), as well as pores. The most noticeable relief elements are flexor lines. White lines (wrinkles) appear due to loss of elasticity and dryness of the skin, as well as age-related changes. These lines usually play an auxiliary role in identification. The most significant are papillary lines and pores, which have a different shape and are located at different distances from one another and from the edges of the papillary lines. These lines on the palms and nail phalanges of the fingers have a rather complex and varied structure (see Fig. 1).

"Fig. 1. Elements of the skin relief on the palmar surface of the hand"

The main properties of the papillary pattern are individuality, stability and recoverability.
Individuality lies in the fact that each person has a pattern pattern that is peculiar only to him. This is due to the peculiarities of the anatomical structure and biological functions of the skin, as well as the genetic originality of a person. Even in identical twins, the set of details of skin patterns never repeats. For more than a hundred years in the world practice of fingerprinting, not a single case of the coincidence of all the details of the skin pattern in different people has been identified. Details are not repeated on different fingers of one person. According to mathematical calculations, the probability of coincidence of papillary patterns on all ten fingers in two people is vanishingly small, so it can be neglected.
Stability means that papillary lines appear on the 3-4th month of intrauterine development of a person and persist until the complete putrefactive decomposition of the skin. With the growth of the organism, only the dimensional characteristics change, but not the patterns themselves.

Restorability guarantees complete renewal of the pattern in case of damage to the upper layer of the skin (epidermis). With a deep injury to the dermis (skin itself), scars or scars are formed, which even increase the number of individualizing signs.
An important characteristic of the skin is the ability to be displayed on those objects that a person has touched. The formation of fingerprints, palms, feet occurs regardless of his will and desire, since it is due to the physiological properties of the skin: its surface is always covered with sweat-fat secretions, which stick to trace-receiving surfaces.
To date, about 30 amino acids have been discovered that are present in the sweat fat substance. Their set for each person is individual, and besides, their ratios in a particular individual are distinguished by a noticeable originality. It is on this that the method of identifying a person by the amino acid composition of his sweat-fat substance is built. Moreover, his biochemical studies allow obtaining information about the blood type, gender, certain diseases of the body, especially those associated with the immune system, medications taken, drugs, habitual food, etc. This significantly narrows the circle of suspects among whom it is necessary to search for the criminal.
The papillary patterns of the nail phalanges are formed by three papillary streams: center lines, peripheral lines and basic lines. The part of the pattern where these streams meet forms a characteristic area called the delta, since it looks like this letter of the Greek alphabet (see Fig. 2).

"Fig. 2. Papillary pattern flows on the nail phalanx of the finger"

Papillary patterns of the nail phalanges of the fingers are divided into types and types depending on the pattern of their center. Based on this basis, three types of patterns are distinguished: arc, loop and curl (see Fig. 3).

"Fig. 3. Types of papillary finger patterns"

The most common loop patterns are 65% of the total. Curl patterns are about 30%, and arc patterns are about 5%. Each type of pattern has varieties depending on the structural features of the central part. So, arc patterns can be simple, tented, etc. (see Fig. 4).

"Fig. 4. Arc patterns of fingers"

Loop patterns are distinguished by the direction of the legs of the loop and the structure of the latter. In the direction of the legs, the loop patterns are divided into radial (the legs are turned towards the thumb) and ulnar (the legs of the loop are turned towards the little finger). Depending on the structure of the loop, the patterns are simple, half-hearted, curved, closed, etc. (see Fig. 5).

"Fig. 5. Looped finger patterns"

Curl patterns are simple: circular, oval, spiral (complex spiral, double helix), (homogeneous and heterogeneous) and complex (see Fig. 6a, 6b).

"Fig. 6a. Simple scroll patterns"

"Fig. 6b. Complex scroll patterns"

In the arc pattern, there is usually no delta, since it is formed by only two streams. In the loop pattern there is one, and in the curl pattern there are two or more deltas. By this feature (the number of deltas), it is easiest to distinguish patterns.
Types and types of papillary patterns, the size of papillary lines, the degree of their curvature, the outline of flexor and white lines are common features.
Particular features of the papillary pattern used for individual identification are individual features in the structure of each specific papillary line, its small morphological differences in detail. These include eyes, islands, hooks, bridges, scraps, bifurcations (forks), the beginning of lines, scars, pores, ruptures, bends, thickenings, features of deltas, dots, merging papillary lines and their fragments (see Fig. 7). For individual identification in the compared traces, it is necessary to identify a unique set of matching particular features.

"Fig. 7. Details of the structure of the papillary pattern"

The mechanism of the formation of handprints and methods for their detection. Traces of papillary patterns suitable for identification are static marks left on a smooth (polished) or plastic surface, the structure of which is much finer than the features of papillaries.

Handprints are superficial and voluminous, visible, weakly visible and invisible, static and dynamic. Weakly visible traces are traces of clean hands, displayed on a material that does not absorb sweat-fat substance. Invisible marks remain on objects whose surface absorbs sweat and grease (paper, fabric, leather, cardboard, plywood, etc.).

In investigative and expert practice, visual, physical and chemical methods for detecting handprints are most often used.
Visual includes the detection of traces with a magnifying glass, with oblique lighting and through the light. These are the best ways to keep the tracks in their original state.
Physical methods are based on the property of sweat-fat secretions to retain particles adhering to them. Powders used to work with low-visibility (weakly visible) and invisible hand marks should be small, dry and contrasting in color with the surface on which the marks are detected. The most common are white powders such as zinc oxide, aluminum powder, and rosin. Black powders are oxides of copper and lead, iron reduced by hydrogen, graphite, and soot. Reduced iron powders are given various color shades, they are given the names of semi-precious stones topaz, ruby, sapphire.
Powders are applied to the surface to be examined with a special flute brush made of very soft squirrel or kolinsky hair. Aerosol dispensers of fingerprint powders are also used. Reduced iron powders are applied with a magnetic brush.

The treatment of traces with iodine vapor is based on the property of adhesion of its smallest particles with sweat-fat substance. The advantage of this method is that traces can be subjected to repeated processing, and the disadvantage is the rapid disappearance of traces, their transition to an invisible state. Vapors of iodine are formed in iodine tubes equipped with a rubber pear, or in a chemical container in which crystalline iodine is heated. Such fumigation is advisable to use when invisible handprints on large surfaces are to be detected. Bright (yellow-orange) staining of traces allows you to establish their localization. The traces are then treated with reduced iron powder. The traces revealed by iodine vapor are fixed by copying onto starch-iodine or iododextrin films. If handprints are left on a multi-colored surface, they must be treated with luminescent powders and then examined in ultraviolet rays. Luminescent powders are prepared from sodium silicylic acid, starch, zinc sulfide, or crystalline camphor.
Chemical methods for detecting invisible traces of hands are the treatment of a trace-receiving surface with substances that react with sweat and fat secretions and stain the traces. It is better to treat with chemical reagents those surfaces that absorb their liquid component.

Chemical reagents used to detect handprints are a 1.5-2% solution of ninhydrin or alloxan in acetone, as well as an alcohol solution of silver nitrate. The reagent must be sprayed onto the surface with a spray gun or, in extreme cases, applied with a cotton swab. The staining reaction of traces does not proceed quickly. To accelerate it, the surface impregnated with ninhydrin must be heated, and the surface impregnated with silver nitrate should be exposed to daylight.
It is recommended to identify handprints only on those items of the scene of the incident that cannot be sent for research because of their bulkiness or high value. Fingerprints found as a result of powdering are very easy to damage, so care must be taken to preserve them. From such objects, traces are copied onto a fingerprint film, which is attached to the decision on the appointment of a fingerprint examination. If necessary, it can be replaced with sticky clerical film. It is even preferable when copying traces from surfaces that are not smooth enough (lacquered countertop, door painted with oil paint).
Traces revealed by iodine vapor are removed using silicone pastes "K" or "U", to which a catalyst and 2-3 drops of orthotolidine are added. Volumetric traces of hands are copied using the same pastes.
Physical methods can reveal relatively fresh handprints, and older ones using chemical reagents.

Fingerprint studies allow solving a number of tasks that are essential for the investigation: to identify the guilty person from among the suspects; establish the identity of the offender using file cabinets; state the fact of committing several crimes by one subject; discover some important circumstances of the crime under investigation; identify the offender.
When appointing a fingerprint examination, it is required to provide the expert with comparative materials: fingerprint cards or blank sheets of paper on which the nail phalanges of the fingers of all suspects are rolled, as well as objects with handprints (their copies) seized from the scene. Sometimes it is also necessary to provide the examiner with the prints of the palms (feet of the feet), as traces at the scene of the incident can also be left by the palms (bare feet).

Most often in investigative practice, traces of hands are found in the form of traces of various sections of the skin relief of the fingers and palms of the hands. In traceology, the study of the structure of the skin patterns of the fingers and palms of the hands in order to use them to identify a person, search, register criminals, and solve other problems is a special branch of forensic science called fingerprinting, which literally means “finger viewing”.

In fingerprinting, a separate section is distinguished that studies the traces of the palms of a person's hands, called palmoscopy.

The ability to classify papillary patterns served as the basis for theoretical and practical developments that are successfully used in the fight against crime.

Most of the papillary patterns on the nail phalanges of the fingers consist of three streams of lines. One is in the central part of the pattern and forms the inner pattern (center). Two other flows - the upper (outer) and lower (basic) - go around the inner pattern from above and below (Fig. 12.2). The section of the pattern where these streams converge resembles the letter "delta" from the Greek alphabet, as a result of which this section of the pattern is called delta. Depending on the number of flows of papillary lines, the shape of the internal pattern, according to the classification system adopted in Russia, the papillary patterns of the fingers are divided into three types: arc, loop and curl, with an additional division of each type into types in accordance with the structural features of the pattern.

Arc patterns are the simplest in their structure and frequency of occurrence - approximately 5%. They consist of no more than two streams of papillary lines that originate from one

Rice. 12.2. The structure of the papillary pattern:
1 - basic flow; 2 - external flow;
3 - internal (central) flow; 4 - delta

the lateral edge of the finger and go to the other, forming in the middle part of the pattern arched figures that bend towards the upper stream. In arc patterns, there is no internal pattern and delta. Among them, the following types are distinguished: simple, hipped and pyramidal (Fig. 12.3).

Loop patterns occur in about 60% of cases. They are formed from at least three streams of lines. The central pattern consists of one or more loops, the lines of which begin at the edge of the pattern and, rising up, return to the same edge. The loop has a head, legs, and an open part. Depending on the shape and number of loops, the relative position of the beginning and end of their legs, loop patterns are divided into simple, curved and closed (racquet loops) (Fig. 12.4).

The direction of the legs of the loops is the basis for distinguishing among the loop patterns ulnar (the legs of the loops are directed towards the little finger) and radial (the legs of the loops are directed towards the thumb).

Curl patterns are diverse in structure, but are somewhat less common than loop patterns, in about 30% of cases. Their internal pattern can be formed by papillary lines in the form of ovals, circles, spirals, loops, or a combination of them. A characteristic feature of the curl pattern is the presence of at least two deltas, one of which is located to the left and the other to the right of the inner part of the pattern. Among this diversity, the following main types of curl patterns can be distinguished: simple, spiral and snail loop (Fig. 12.5).

Fig.12.3. Types of arc patterns: a) simple; b) pyramidal; c) tent

Rice. 12.4. Types of loop patterns: a) simple; b) curved; c) closed

In some classifications, other types of curl patterns are also distinguished, for example, circular, loop-spiral, loop-ball, complex, incomplete, etc., and among loop patterns - half, parallel and counter.

In addition, there are papillary patterns of the nail phalanges of the fingers, which cannot be attributed to any of the three classification groups, the so-called transitional patterns - false (false-loop and false-curl).

Identification signs of the structure of papillary patterns are usually divided into general and particular. Common features include: type and type of papillary pattern; direction and steepness of papillary lines flows; the structure of the central pattern of the pattern; delta structure; the number of papillary lines between the center and delta; interposition of deltas, etc.

Rice. 12.5. Types of curl patterns: a) simple; b) snail loop; c) spiral

Particular features (Fig. 12.6) include details of papillary patterns (beginning and ending, merging and branching of papillary lines, island (eye), bridge, hook, fragment, dot, thin papillary line, opposite position of papillary lines) and papillary lines (breaks , breaks, bends, thickenings, configuration of the edges of papillary lines).

As for the skin relief of the palmar surface, it consists of papillary lines, skin folds, interphalangeal folds (on the fingers) and flexor lines (on the palm).

On the palmar surface, two main areas are distinguished, the papillary patterns of which differ from each other in the direction, the steepness of the papillary line flows and the shape of the patterns they form: tenar - an area located around the base of the thumb; hypothenar - a site located against the little finger at the outer edge of the palm (Fig. 12.7).

Types of handprints. Handprints, depending on the mechanism of formation, can be voluminous and superficial, colored and colorless, hardly visible and invisible. Volumetric traces are formed as a result of contact of hands with a plastic surface (on

Rice. 12.6. Particular signs of papillary patterns:
1 - the beginning of the line; 2 - pores; 3 - branching lines;
4 - bend; 5 - bridge; 6 - oncoming line;
7 - peephole; 8 - merge lines; 9 - interpapillary lines (scallops);
10 - short line; 11 - the end of the line;
12 - hook; 13 - islet; 14 - line break;
15 - thickening of the line

Rice. 12.7. The structure of the human hand

oil, fresh paint, plasticine, icy surfaces, etc.). Surface marks are formed on hard surfaces due to delamination or layering of a trace-forming substance. Detachment traces are formed as a result of adherence of trace-carrier particles to the hands, layering traces - as a result of adherence to the trace-receiving surface of particles of a substance present on the hands (sweating substance, ink, blood, paint, etc.). Surface traces can be colorless, resulting from the layering of a colorless sweat-fat substance on the trace-receiving surface, and colored, formed by hands covered with blood, ink, liquid paint, etc. Hardly visible handprints are formed on smooth non-porous surfaces (glass; objects coated with varnish, enamel, plastic, etc.), invisible ones appear on porous surfaces (paper, cardboard, plywood, raw wood, etc.).

This is the first article in a series about fingerprints. In this series, we will explain the scientific basis and methods used in our fingerprint time attendance system.

Fingerprinting and a bit of history.

The basis of all modern biometric systems is classical fingerprinting, which for centuries has been one of the main methods of identifying a person for criminologists (the English anthropologist Francis Galton achieved the introduction of fingerprinting as a method of registering criminals in England in 1895).
Fingerprinting- This is the identification of the subject by the papillary pattern of the fingers. papillary pattern- this is the surface layer or epidermis on which the relief lines protrude on the palmar and plantar surfaces.

The vast history of fingerprinting as a science has served to develop the scientific basis for modern identification algorithms that use fingerprints as an identifier.

Fingerprinting is based on the fact that in the entire history of this science, not a single pair of 100% similar to each other has been identified. It is also scientifically proven that a person's fingerprints change slightly with age (they are formed in the womb). Even mechanical injuries of the skin do not significantly change the pattern, unless, of course, they affect the entire surface of the finger.

classification of fingerprints.

If you look closely at the fingers on the hands, you can see that they have a complex relief pattern of elevations (ridges) and depressions (grooves). Despite all the variety of patterns, prints lend themselves to strict classification and are divided into three main types:

Arc,
Loopback
Curl.

Arc patterns.

Arc patterns - in the middle part of the imprint they have a bend - an internal arc - the shape of which serves to divide such imprints into subspecies. According to the Russian classification system, an arc pattern can be:

simple,
tented
with an indefinite structure of the center,
false loop,
false curl,
abnormal.

Loop pattern.

Loop patterns form "loops" of papillary lines that are directed upward and towards the center. To classify an imprint as an arc type, it is necessary that at least one of the loops has a completed loop head or a complete loop.
Arc patterns have eight subspecies:

Simple,
Curved,
half-hearted,
Closed,
"Parallel Loops"
"Counter Loops"
false-curl,
Loop (the most rare).

Curl patterns

Such patterns are formed by a directed field of papillary lines, which in the middle part of the pattern is curved in the form of circles, ovals, spirals, lines that envelop each other in various configurations. There are 11 varieties of the curl pattern, due to the peculiarities of the internal structure:

Simple pattern - circle,
Simple pattern - oval,
Simple pattern - spiral,
Loop-spiral,
spiral loops,
Loop - snail,
curved loop,
Incomplete curl pattern,
Loops-balls with a versatile and one-sided arrangement of the legs of the loops and
Rarely seen swirling patterns.

It is worth noting that different countries use different classification systems, so the subspecies of the basic print patterns may be different.

Despite the infinite number of types of papillary patterns, one cannot rely on this pattern to uniquely identify a subject. Pattern types are only first level details that allow you to narrow down your search in the fingerprint database if the comparison is 1:N.

For unambiguous identification, details of the second and third levels are used.
These features of fingerprints make it necessary to apply a finger to the scanner several times to enter the fingerprint into the database. Several applications allow you to clearly highlight all the features of the user's fingerprint for subsequent unique identification.

As you can see, fingerprinting is a very complex and exact science, operating with a powerful mathematical apparatus for digitizing and storing fingerprints. Therefore, when choosing a fingerprint identification system, it is necessary to pay attention to the compliance of the system algorithms with international standards.

Our Simple WTC system uses certified proprietary algorithms that comply with the standards

ISO 19794-4:2005, ANSI/INCITS 381-2004, ISO/IEC 19794-2:2005, ANSI INCITS 378-2004, MINEX Certification, FBI FIPS 201 PIV certification

This allows, at a high processing speed, to identify the subjects of the system with almost 100% accuracy.

Daktylos - finger and skopeo - look), which literally means "finger-gazing".

In fingerprinting, a separate section is distinguished that studies the traces of the palms of a person's hands, called palmoscopy (from Latin palma - palm and Greek skopeo - I look).

The ability to classify papillary patterns served as the basis for theoretical and practical developments that are successfully used in the fight against crime.

Arc patterns are the simplest in their structure and frequency of occurrence - approximately 5%. They consist of no more than two streams of papillary lines that originate from one

Rice. 12.2. The structure of the papillary pattern:

1 - basic flow; 2 - external flow; 3 - internal (central) flow; 4 - delta

Fig.12.3. Types of arc patterns: a) simple; b) pyramidal; c) tent

Rice. 12.4. Types of loop patterns: a) simple; b) curved; c) closed

Rice. 12.5. Types of curl patterns: a) simple; b) snail loop; c) spiral

As for the skin relief of the palmar surface, it consists of papillary lines, skin folds, interphalangeal folds (on the fingers) and flexor lines (on the palm).