Left eye viewing angle decreased. How wide do you see? Expanding the angle of human vision

Any person who is more or less familiar with photographic equipment and with a love for knowing the world around him, probably, more than once had a question in his head, how do the human eye and a modern digital camera compare in terms of their parameters? What is the sensitivity of the human eye, focal length, relative aperture and other interesting little things. Which I will tell you today :)

So, having climbed the floor of the Internet, I came to the conclusion that so far not a single article has been written in Russian that would put an end to the description of the human eye in terms of technical parameters or cover the topic more or less densely.

Photographic parameters of the human eye and some features of its structure

Sensitivity (ISO) human eye dynamically changes depending on the current level of illumination in the range from 1 to 800 ISO units. The time of complete adaptation of the eye to a dark environment takes about half an hour.

Number of megapixels in the human eye is about 130, if we count each photosensitive receptor as an individual pixel. However, the central fovea (fovea), which is the most light-sensitive area of the retina and is responsible for clear central vision, has a resolution of the order one megapixel and covers about 2 degrees of view.

Focal length equals ~ 22-24mm.

The size of the hole (pupil) with an open iris equals ~7mm.

Relative hole equals 22/7 = ~3.2-3.5.

Data bus from one eye to the brain contains about 1.2 million nerve fibers(axons).

Bandwidth the channel from the eye to the brain is about 8-9 megabits per second.

Viewing angles one eye is 160 x 175 degrees.

The human retina contains approximately 100 million rods and 30 million cones. or 120 + 6 according to alternative data.

Cones are one of two types of photoreceptor cells in the retina. The cones got their name because of their conical shape. Their length is about 50 microns, diameter - from 1 to 4 microns.

Cones are about 100 times less sensitive to light than rods (another type of retinal cell), but are much better at picking up fast movements.
There are three types of cones, according to sensitivity to different lengths waves of light (flowers). S-type cones are sensitive in violet-blue, M-type in green-yellow, and L-type in yellow-red. The presence of these three types of cones (and rods, sensitive in the emerald green part of the spectrum) gives a person color vision. Longwave and mediumwave cones (with peaks in blue-green and yellow-green) have wide sensitivity zones with significant overlap, so certain types of cones respond to more than just their own color; they just react to it more intensely than others.

At night, when the flow of photons is insufficient for the normal operation of the cones, only the rods provide vision, so at night a person cannot distinguish colors.

Rod cells are one of two types of photoreceptor cells in the retina of the eye, so named for their cylindrical shape. The rods are more sensitive to light and, in the human eye, are concentrated towards the edges of the retina, which determines their participation in night and peripheral vision.

In the human eye, adapted mainly to daylight, when approaching the middle of the retina, the rods are gradually replaced by cones more suitable for daylight (the second type of retinal cells) and are not found at all in the fovea. In animals leading a predominantly nocturnal lifestyle (for example, cats), the opposite picture is observed.

The sensitivity of a rod is sufficient to register the hit of a single photon, while cones need to hit from several tens to several hundred photons. In addition, several rods are usually connected to one interneuron, which collects and amplifies the signal from the retina, which additionally increases sensitivity due to the sharpness of perception (or image resolution). This combination of rods into groups makes peripheral vision very sensitive to movements and is responsible for the phenomenal ability of individuals to visually perceive events that lie outside their angle of vision.

Because all rods use the same light-sensitive pigment (instead of three like cones), they contribute little or nothing to color vision.

Also, rods react to light more slowly than cones - the rod reacts to a stimulus within about a hundred milliseconds. This makes it more sensitive to smaller amounts of light, but reduces the ability to perceive fast changes, such as rapid image changes.

The sticks perceive light mainly in the emerald green part of the spectrum, so at dusk the emerald color seems brighter than all the others.

However, it should be remembered that the structure of the camera is different from the structure of the eye. When shooting with a camera or camcorder, the image is divided into frames. Each frame is "removed" from the matrix at a certain point in time, i.e. the finished image enters the processor.
While the human eye sends a constant video stream to the brain without breaking it into frames. Therefore, it is possible to misinterpret some parameters if you do not understand the issue more or less thoroughly.
As a result, we can say that in terms of sensitivity, the human eye has caught up with almost all mid-end photographic equipment, and high-end has generally surpassed it many times over. However, the noise level of the most common mid-end technology is much higher than that of the retina, and the image quality is an order of magnitude worse.

The retina also differs from photosensors in that the sensitivity on it changes for each individual photoreceptor depending on the illumination, which makes it possible to achieve a very high dynamic range of the final image. Sensors with similar technology are already being developed by many companies, but are not yet available.

At the moment, a device with the size of a human eye has not yet been invented, comparable to it either in terms of optical or technical parameters.

Used sources:
http://www.clarkvision.com/imagedetail/eye-resolution.html
http://webvision.umh.es/webvision/
http://forum.ixbt.com/topic.cgi?id=20:17485
http://ru.wikipedia.org/wiki/Cones_(retina)
http://ru.wikipedia.org/wiki/Sticks_(retina)
http://en.wikipedia.org/wiki/Retina

p.s. I did not find exact data for one or another value, I had to use average, more real and most frequently occurring data. Therefore, if you find an error or consider that you understand the topic better, please unsubscribe in the comments, please. I would be very interested to know your opinion and your additions.

The total number of projections of all spatial microdots that fall into the field of view in the state of fixation on one of the points, in medical terminology, is called the "angle of view". All objects that are visible to a person at this moment are projected onto the corpus luteum of the retina. The field of view is the ability to perceive one's own position in subspace, this value is measured in degrees.

Vision Options

The visual complex of the patient is a complex structure, with the help of which the object examines the objects around him, freely orients himself in the areas, regardless of the lighting conditions, and moves seamlessly in it.

Ophthalmological research has divided vision into two main types.

Central - reproduced by the central part of the retina, is responsible for the analysis of the forms of visible objects, fine detail and visual acuity. This view is inextricably linked with the angle of view - the value formed between two points located at the edges. The higher the angle, the lower the sharpness level.
Peripheral - helps to evaluate things located near the focus point eyeball. This species is responsible for orientation in space under any lighting conditions. The visual acuity of this subspecies is weaker than that of the central one. Secondary vision is directly related to the field - the space fixed without the need for additional eye movement.

Both types make up the overall picture when trying to consider the surrounding things with their relation to space.

Standard dimension

The structure of the body of any person is strictly individual, due to which the angle of view and the field may differ in performance. The main influence on them (on the angle of view and field) is exerted by:

specific features of the personal construction of the eyeball;
the shape of the eyelids, their dimension;
individual characteristics in the structure of the eye orbits.

The angle of view is directly dependent on the object under consideration - on its size, being at a distance from the eyes (in this case, the field of view expands if the object is at a close distance).

The natural limiters of the angle of view are anatomical features facial structures - eyelids, superciliary arch, bridge of the nose. These factors give insignificant deviations; against the background of the collected data, a conditional norm of the visual angle was made for all the studied patients - 190 degrees.

Techniques for expanding the angle of view

Designed to increase the field of view for better orientation in the surrounding space, extensive perception and analysis of the information received. The main example is reading books on any media - the patient remembers the information viewed faster and better.

An important factor in improving these features is pre-treatment. possible diseases, which caused the narrowing of the node or field of view. After correctly carried out therapeutic measures, the patient can engage in techniques for expanding the field of view. They are also recommended to be taken into account by healthy people - to improve overall visual perception.

The basis of these methodological actions is changing the distance when reading literature. Viewing at different distances (near, far) will significantly expand the angle of view.

Diagnostic studies

The process of falling out of the considered objects from the field of view can occur both gradually and in an accelerated manner. In this regard, all citizens are recommended to undergo an annual planned medical checkup to identify the initial stages of deviations.

modern medicine conducts the studies necessary to determine the deviations using this technique is able to identify beginning deviations from the general standards, its implementation is painless for the applicant.

Diagnosis is carried out according to the following scheme:

If additional consultation is necessary with a highly specialized doctor, the patient is given the result of the tests on the carrier or in printed form.

Diseases that cause pain in the corners of the eyes

Painful manifestations located in the outer or inner corner of the eye are accompanied by a number of specific symptoms:

hyperemia of the eyeball;
sensation of itching on the surface of the skin;
secretions that accumulate in the corners of the eyes;
profuse lachrymation.

The main causes of such symptoms are some diseases.

All of the above diseases are treated with specialized means prescribed by an ophthalmologist. At home, you can alleviate the condition with cold compresses and moisturizers. eye drops. Contacting medical institution at the first manifestations - necessarily.

Early diagnosis and timely prescribed procedures will help to avoid complications and further development of the infectious and inflammatory variant of the disease. Prolonged use of cold or warm compresses will help further development of pathological processes.

Diseases determined by determining the angle of view

Small deviations from generally accepted normative data indicate the presence of pathological processes in the body. After determining the angle, field and designation of the loss of individual sections, the medical staff determines a specific ailment, leading to the development of further processes. The doctor determines:

the exact location of the hemorrhage;
the presence of tumors;
retinal detachment;
inflammatory processes;
retinitis;
glaucoma;
exudates;
hemorrhagic changes.

To confirm changes in the fundus, the method of ophthalmoscopy is additionally used. In variants where the patient's angle of view is measured, the visual analyzer gives out a part of the image (up to half of the overall picture), there are suspicions of tumor-like processes and extensive hemorrhages in the brain.

Further treatment of such deviations is carried out according to symptomatic phenomena, general therapy pathological conditions does not exist. Refusal of the necessary treatment will complicate the situation with the further development of tumors and deterioration general condition after local hemorrhages.

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Vision Options

Ophthalmological research has divided vision into two main types.

Central - reproduced by the central part of the retina, is responsible for the analysis of the forms of visible objects, fine detail and visual acuity. This view is inextricably linked with the angle of view - the value formed between two points located at the edges. The higher the angle, the lower the sharpness level.
Peripheral - helps to evaluate things located near the focus of the eyeball. This species is responsible for orientation in space under any lighting conditions. The visual acuity of this subspecies is weaker than that of the central one. Secondary vision is directly related to the field - the space fixed without the need for additional eye movement.

Both types make up the overall picture when trying to consider the surrounding things with their relation to space.

Standard dimension

specific features of the personal construction of the eyeball;
the shape of the eyelids, their dimension;
individual features in the structure of the eye orbits.

The natural limiters of the angle of view are the anatomical features of the structure of the face - the eyelids, the superciliary arch, the bridge of the nose. These factors give insignificant deviations; against the background of the collected data, a conditional norm of the visual angle was made for all the studied patients - 190 degrees.

Process features and interesting facts

The organs of vision are a complex system through which we can collect visual information. The organ of vision is one of the most important sense organs, which directly affects the functioning of the brain and the development of intelligence and speech. This organ belongs to the peripheral part of the visual analyzer and consists of the eyeball.

All these components of the eyeball are interconnected, and therefore, if one of them is damaged, the visual function will be impaired.

What each of the shells is, and what function it performs, we wrote earlier.

But what are Interesting Facts about the human organs of vision:

Techniques for expanding the angle of view

An important factor in improving these features is the preliminary treatment of possible diseases that caused the narrowing of the node or field of view. After correctly carried out therapeutic measures, the patient can engage in techniques for expanding the field of view. They are also recommended to be taken into account by healthy people - to improve overall visual perception.

The basis of these methodological actions is changing the distance when reading literature. Viewing at different distances (near, far) will significantly expand the angle of view.

Diagnostic studies

The process of falling out of the considered objects from the field of view can occur both gradually and in an accelerated manner. In this regard, all citizens are recommended to undergo an annual scheduled medical examination to identify the initial stages of deviations.

Modern medicine conducts the studies necessary to determine deviations using computer perimetry. This technique is able to identify beginning deviations from the general standards, its implementation is painless for the applicant.

Diagnosis is carried out according to the following scheme:

If additional consultation is necessary with a highly specialized doctor, the patient is given the result of the tests on the carrier or in printed form.

The influence of the computer on human vision

The influence of a computer on human vision is not unambiguous. Most people are convinced that a computer monitor, or rather its radiation, simply kills vision. That the computer causes fatigue, dry eyes and so on.

What is actually happening? Does the computer affect the quality of vision?

According to numerous studies by American and European researchers, ultraviolet and X-ray radiation that comes from a computer monitor is very insignificant and cannot harm vision. A much larger "portion" of these rays comes from incandescent lamps.

human vision photoAt the same time, a modern computer monitor is covered with a special protective film that minimizes radiation even more. This film can be compared to sunglasses. This applies to modern monitors, the elements of which practically do not blink, do not contain mercury and other harmful substances.

At the same time, one cannot argue with the fact that since the computer has become a natural "inhabitant" in every home, the number of people with visual impairments has increased.

The negative impact of the computer on vision is due to the following reasons:

Long and continuous work at the computer. If you work at the computer all day, and in the evening watch movies on the computer, communicate in in social networks, then it is no wonder that the eyes turn red, watery, the clarity of readable information is disturbed, and so on. Children are especially prone to fatigue, so they especially need to control the time spent in front of the computer.
Non-compliance with visual hygiene. That is, in most cases workplace and the time is not organized correctly: the computer is too close to the eyes, it is wrong in relation to the window. In addition, users often sit hunched over with their heads thrust forward. This disrupts the transmission of nerve impulses to the brain and thus, the person sees poorly and gets tired quickly.
Poor quality lighting. If you work in front of a computer in a dark room, or in a poorly lit room, your eyes quickly get tired due to tension.

Diseases determined by determining the angle of view

the exact location of the hemorrhage;
the presence of tumors;
retinal detachment;
inflammatory processes;
retinitis;
glaucoma;
exudates;
hemorrhagic changes.

Further treatment of such deviations is carried out according to symptomatic phenomena; there is no general therapy for pathological conditions. Refusal of the necessary treatment will complicate the situation with the further development of tumors and the deterioration of the general condition after local hemorrhages.

This article examines in detail the concept of "field of view", ways to determine the indicators of this parameter in humans and its significance in ophthalmology.

The size of the field of human vision

All people are unique, each person has certain characteristics. The angle of view and the size of the field of view are different for everyone. For a particular person, they are determined by the following factors:

individual features of the eyeball;
individual shape and size of the eyelids;
individual features of the bones near the orbits of the eyes.

In addition, the angle of view is determined by the size of the object being viewed, and the distance from it to the eye (this distance and the field of view of a person are inversely related).

The structure and structure of his skull are the natural limiters of the field of view. In particular, the angle of view is limited to the brow ridges, bridge of the nose, and eyelids. However, the limitation created by each of these factors is insignificant.

190 degrees - this is the value of the angle of view of both human eyes. One individual eye has the following normal values:

55 degrees for gradation up from the fixation point;
60 degrees for gradation to the underside and to the side going inward from the nose;
90 degrees for gradation from the side of the temple (outside).

When the study of the visual fields showed a discrepancy normal level, it is necessary to determine the cause, often associated with the eyes or the nervous system.

The angle of view improves the spatial orientation of a person, allows him to receive more data about the world around him, entering the brain with the help of visual receptors. As a result of scientific research on visual analyzers, it was found that the human eye can clearly distinguish one point from another only if it focuses at an angle of at least 60 seconds. Since the angle of human vision directly determines the amount of perceived information, some people strive to achieve its expansion, since this allows them to read texts faster and remember the content well.

Ophthalmological significance of visual fields

Peripheral vision determines the visual fields for different colors perceived by human eyes. In particular, the most deployed angle is at white color. In second place is blue, and in third is red. The narrowest angle occurs in the visual perception of green. Examination of the patient's visual field allows the optometrist to identify visual abnormalities present.

At the same time, even a slight deviation in the fields sometimes indicates severe eye pathologies. Each person has their own individual norm, but certain general indicators are used to detect deviations.

Modern ophthalmologists, having discovered a discrepancy of this kind, can identify eye diseases and some other ailments, primarily associated with the central nervous system. In particular, by determining the angle and field of view, as well as the places where the visual fields fall out (disappearance of the image), the doctor is able to easily identify the place where hemorrhage occurred, a tumor or retinal detachment occurred, or inflammation occurs.

Measurement of fields of view

Computer eye perimetry — modern method diagnosing the narrowing of the field of human vision. Now this method has a very affordable price. This is a painless procedure that takes little time and allows you to detect deterioration in peripheral vision in order to start treatment in time.

How the process goes:

The first stage is a consultation with an ophthalmologist, during which he gives instructions. Before proceeding with the procedure, the doctor should explain in detail all its nuances to the patient. In this study, optical devices are not used. If the patient wears glasses or lenses, he will have to remove them. The left and right eyes are examined separately.
The patient directs his gaze to a fixed point located on a special device surrounded by a dark background. During the process of determining the patient's angle of view, dots appear on the periphery that have different levels of brightness. These points are to be seen by the patient in order to be fixed using a special remote control.
There are changes in the layout of points. Usually this scheme is repeated by a computer program and thanks to this, the moment of loss of the area of vision can be determined with absolute accuracy. Since in the process of performing perimetry there is a possibility that the patient will blink or press the remote control untimely, the repetition method is more correct, it leads to an accurate result.
The study takes place quite quickly, in a few minutes a special program will process all the information and give the result.

In some clinics, such information is issued in printed form, in others it is recorded on a disk. This is quite convenient when a consultation with a doctor of a different specialization is planned, and for assessing the dynamics during the treatment of the disease.

Expanding the angle of human vision

Many studies have led to the conclusion that during the treatment of diseases that caused deterioration this indicator, you can increase the angle of human vision by special exercises. A completely healthy person can take advantage of this opportunity in order to improve individual visual perception.

A set of such exercises is called a representational technique and involves some special actions in the course of ordinary reading. For example, you can change the distance from the text to the eyes. At regular Such a procedure improves the value of the individual angle of view, which provides some advantages, since the quality of vision is largely determined by its angle.

Article author: Vladislav Solovyov

The angle of human vision today is one of the most important components of the functioning of the human visual system. Under this concept, many experts mean the sum of the projections of all spatial points that can fall into the field of vision of a person in a state of fixing the eye on a certain point.

Determining the angle of view

Everything that the patient sees will be projected onto the retina in the area corpus luteum. Visual fields are the ability to quickly perceive one's position in space. This ability is measured in degrees.

Central and peripheral vision

The human visual system is quite complex. Therefore, it allows you to consider objects, the world around you, navigate in space under different lighting conditions and move around in it. In ophthalmology today there are two types of vision:

Central. It is an important part of the human visual system. It is provided by the central part of the retina. It is with the help of this vision that you will have a wonderful opportunity to analyze the forms of the visible and small details. The central visual perception of a person will be directly related to the angle of view, which is formed between two points located at the edges. The larger the angle readings, the lower the sharpness.
Peripheral. This type of vision provides a wonderful opportunity to analyze objects that have been located around the focal point of the eyeball. It is it that further allows you to navigate in space and darkness. Peripheral vision in its sharpness is much lower than the central one.

It's important to know! If the central vision of a person is directly proportional to the angle of view, then the peripheral will depend directly on the field of view.

What is the optimal field of view

Each person today has his own characteristics. Therefore, the angles and field of view are individual and may differ from each other. A person's field of view in degrees is usually affected by the following factors:

specific features of the structure of the human eyeball;
the shape of the eyelids and their size;
features of the composition of the bones of the eye orbits.

Also, the angle of view of a person will depend on the size of the object in question and its distance from the eyes. The structure of the human visual system, as well as the structural features of the skull, are natural limiters to the angle of view laid down by nature. However, the angle of limitation of all these factors is insignificant.

It's important to know! Experts conducted numerous studies as a result of which it was possible to find out that the angle of view of both human eyes is 190 degrees.

The norm of the field of view for each individual human analyzer will be as follows:

50-55 degrees for gradation up from the fixation point;
60 degrees for down measurement and for side away inside from the nose;
from the side of the temporal region, the angle can increase up to 90 degrees.

If a person's vision examination shows a discrepancy to the norm, then the need to identify the cause, which is most often associated with vision problems. The angle of view allows a person to navigate much better in space and receive more information that comes through the visual analyzer.

Perimetry norm

The study of the visual analyzer showed that the human eye clearly distinguishes two points when it is focused at an angle of at least 60 seconds. According to many experts, the angle of view will directly affect the amount of information received.

Measuring fields of vision

Recently, the definition of visual fields is a really important task. The human visual analyzer is a complex optical system that has evolved over a long period of time. Different color rays are associated with a variety of information components, so the human eye perceives them differently. The peripheral ability of visual analysis affects the different color rays that are perceived by our eye.

The most developed corner has a white tint. Then comes blue and red. Most of all, the angle of view decreases when analyzing green shades. In most cases, even a slight deviation can indicate serious pathologies in the visual system. Each person has his own norm, but there are indicators by which the deviation is determined.

Modern medicine allows you to perform a qualitative study of visual fields and quickly determine the ailments of the visual system. By determining the angle and finding out the loss of the image, the doctor can quickly determine the place of hemorrhage and the appearance of tumor processes. A good ophthalmologist as a result of the examination can identify the following violations:

Exudates.
Retinitis.
Hemorrhages.

In the presence of such conditions, the measurement of the angle of view draws a general picture of the condition of the fundus, which is further confirmed by ophthalmoscopy. The study of this indicator and the deviation from the norm also gives a picture of the state of the visual analyzer when diagnosing glaucoma. Even on early stages of this disease, you will be able to notice certain changes.

If a significant part of the problem falls out in the process of diagnosing the problem, then this is a serious suspicion of a tumor lesion or massive hemorrhage in certain areas of the brain.

How is the measurement carried out

With a sharp decrease in the angle of view, a person will definitely be able to notice this. If the decrease in the angle of view occurs gradually, then this process may go unnoticed. That is why many experts recommend an annual examination, which will quickly detect various deteriorations. Diagnosis and determination of the narrowing of the field of view in modern ophthalmology is carried out by an innovative method, which is called computer perimetry. The cost of such a procedure is quite low, and the duration is only a few minutes. However, thanks to computerized perimetry, it is possible to quickly determine the decrease in peripheral vision, even with small deviations, and quickly begin treatment.

The diagnostic procedure consists of the following steps:

Conducting a study to determine the angle of the field of view begins with a consultation with a specialist. Before the procedure, the doctor must necessarily tell all the features and rules of the procedure. The patient is being examined optical devices. Each eye of the patient is examined separately.
The patient should focus his gaze on a static point, which is located on the dark background of the device. During the procedure for measuring the angle of the field of view, bright points will appear in the peripheral field with different intensities. This is what the patient's eye should see.
The layout of points is constantly changing, and this allows you to determine with 100% accuracy the moment of loss of the site.
The speed of this survey is quite fast and in a few minutes the program will process the information received and give the result.

Most modern clinics today issue information in printed form. Others provide the opportunity to record the received data on information media.

How to expand the field of view

A wide field of view allows a person to better navigate in space and perceive information more extensively. When reading a book, a person with a wide angle of vision will do it much faster.

Numerous studies have shown that the angle of the field of view can be further expanded with the help of special exercises. It is possible to develop the capabilities of the visual analyzer and absolutely healthy person. This will greatly improve the perception of the surrounding world. The scheme of such classes has a name - representation. talking in simple words such exercises will be associated with certain actions during a process such as reading. By doing this regularly, you will be able to expand the angle of view.

Many experts today recommend that you monitor your health. Therefore, try to visit an ophthalmologist more often. Any disease is much easier to treat in the early stages, and diagnosing the fields and angle of view is an indicative way of early diagnosis of many ailments.