Hole glasses to improve vision - reviews about perforated glasses for the eyes. Glasses as a method of vision correction Spectacle vision correction in children

05.04.2020 -

The selection of glasses is made according to the Donders principle - to prescribe the minimum negative lens that gives maximum visual acuity. If you add another -0.25D to the selected correction, and visual acuity does not improve, then this lens is already redundant. Control - duochrome test (should show a slightly clearer image on a red background) or test with a grid and cross-cylinders: set the negative axis of the cylinder to 90 degrees. If the patient sees vertical stripes better, then you need to increase the negative component (add - 0.25D) until the horizontal and vertical lines are seen equally.

Congenital myopia

Congenital myopia(its frequency does not exceed 2%), if bilateral up to 5.0 D, then in children under 3 years of age correction is not prescribed, because the child sees close objects and there is no threat of amblyopia.

For unilateral myopia and signs of DECOMPENSATION, namely: progression, amblyopia, asthenopia, strabismus - portable glasses are recommended or preferable contact correction especially for children.

There are many different, sometimes completely opposite, views on the correction of myopia, so the recommendations given are somewhat conditional.

By modern views, the correction must be complete, especially if there is asthenopia or special requirements for the profession. Binocular visual acuity must be at least 1.0

Low myopia

With myopia up to 1.0 D, glasses or contact lenses can be worn only as needed, for example, when driving a car. If the visa is 0.4-0.5, the age is from 7 to 18 years, the correction is prescribed depending on the desire - permanent or impermanent. With this type of refraction, there is always a zone of clear vision at a certain distance from the eye and amblyopia does not develop. “Glasses in your pocket” - only when necessary, for distance.

Moderate myopia

For distance, it is recommended that children and adults always wear glasses, a complete but tolerable correction. For a long time It was believed that incomplete correction and bringing visual acuity to 0.7-0.8, no more, was sufficient. Now researchers warn against incomplete correction, because They believe that it contributes to the progression of myopia and insist on the most complete correction as tolerated.

When working at close range, myopes usually remove glasses or use weaker glasses for near.

There are studies showing negative effect constant undercorrection and have proven that UNDERCORRECTION DOES NOT LEAD TO A SLOW DOWN OF PROGRESSION OF MYOPIA (two-year study by Chung, Mohidin, O, Leary).
The theory of RETINAL DEFOCUS - emmetropization near (Van Alphen -1961, Earl Smith).

The theory is based on the well-known mechanism for regulating the length of the eyeball - the physiological mechanism of emmetropization. An unclear image on the retina (defocus) leads to a decrease in the production of special neuromodulators in it. This, in turn, reduces the production of proteoglycans, which are responsible for the strength of the sclera. In the absence of a clear image on the retina and the appearance of aberrations, the photoreceptors of the paramacular zone are stimulated, from them information goes to the subcortical center, which controls the process of emmetropization - placing focus on the retina. The ciliary muscle and choroid (choroid) form an elastic membrane and it is its tone that regulates the stretching of the sclera. When near vision occurs, the posterior pole of the eye shifts backward, and the sclera becomes deformed, because the mechanical properties of the sclera in the posterior sections are weaker.

It turned out that PERIPHERAL VISION has a key influence on the process of emmetropization. Earl Smith showed that it is peripheral refraction that determines the rate of growth of the eye in length (elongation); central refraction is not so important. The posterior pole of the eye tends to correspond to peripheral focusing. If, using a correction tool, a sharp image is created in the center of the retina, then its peripheral area with a blurred image will be in the hypermetropic zone, i.e. behind the eye (Fig. 2). If the peripheral focus is behind the eye (hypermetropic type), then this accelerates the growth of the eye. If peripheral focusing is myopic, then this slows down elongation. Conventional spectacle correction, while providing central emmetropization, produces hypermetropia in the periphery. This explains why central myopic defocus when fitting glasses or contact lenses (undercorrection) does not help slow the progression of myopia.

Orthokeratology lenses reduce hypermetropic defocus, thereby preventing the progression of myopia. Soft CLs reduce defocus by an average of 2 times, while hard CLs eliminate it completely.

Prolonged work near, combined with a delay in the accommodative response, with insufficient accommodation leads to an elongation of the eye axis by including the above physiological mechanism emmetropization. When working at close range with uncorrected myopia, there is a delay in the accommodative response of +1.0 D or more.

According to the COMET studies, myopia progressed most strongly in the group of patients with delayed accommodation and near esophoria. In this group, progressive lenses effectively slowed the growth of myopia or contact lenses plus glasses were used for near myopes with esophoria.

High myopia

For myopia greater than 6.0 D, full correction often causes discomfort, so only well-tolerated lenses are prescribed. Intolerance to full correction may occur because strongly concave lenses reduce the image on the retina and incorrect projection of objects occurs, their size and shape are distorted, and distance assessment is impaired. At high degrees ametropia and myopia and hypermetropia complain that they cannot walk up the stairs with glasses, they stumble out of the blue, dizziness and nausea appear. It is recommended to start using glasses at home, first for a few minutes, then increase the wearing time, and go outside first for a short time and on familiar paths. Gradually everything discomfort will pass.

Spectacle and contact correction

Light-scattering glass - concav - acts the more strongly the closer it is to the eye. When selecting glasses, such glass must be inserted into the frame into the groove of the lens holder located closer to the eye.

Myopic eye with high myopia looks (without glasses) large, convex, the cornea is large, the anterior chamber is deep, the pupil is dilated. In strong glasses, the eye appears small and its natural dimensions are distorted.

For a combination of myopia and convergence insufficiency (distance and near exophoria), constant maximum spectacle correction for distance and near is recommended.

When myopia is combined with convergence excess, when there is distance orthophoria and near esophoria and delayed accommodation, progressive lenses effectively slow down the growth of myopia.

Myopia up to 6.0 D and weakened accommodation - full correction for distance, weaker lenses for working at close range.

Myopia up to 6.0D and normal accommodation - permanent full correction.

Myopia above 6.0 D is a permanent correction, the value of which for distance and near is determined by tolerance.

A study of refraction in children and adolescents using orthokeratology lenses showed that reverse profile lenses, creating myopic defocus, lead to a slowdown in eye growth and a cessation of the progression of myopia.

Special contact lenses have been developed under the leadership of B. Hodden that reduce peripheral hypermetropic defocus. Their design involves a distance zone in the center and an increase in positive refraction towards the periphery.

When examining a patient with myopia, you should always think about the possibility of accommodation spasm (exclude it by doing special studies) and keratoconus (everyone should undergo keratometry to determine the radius of curvature of the cornea).

Types of lenses used in the manufacture of glasses:

spherical - both surfaces of the lens are spherical or one of them is flat. Spherical lenses are divided into collective or positive (used for hypermetropia - a violation of refraction (the process of refraction of light rays into optical system eyes), in which the light falls not on the retina, but behind it - a person sees blurry near, well - in the distance (with a high degree of hyperopia, the patient sees poorly both near and far)) and concave (scattering or negative) - used for myopia - refractive error when light is not focused on the retina ( inner shell eyes), and in front of it - a person sees well near, blurry into the distance;
cylindrical lenses - used to correct astigmatism - a violation of the sphericity of the eye - with this refractive error, the light is focused not in one place of the retina, but in several - astigmatists have visual impairment both near and far;
prismatic lenses - used to correct heterophoria - hidden strabismus - a condition in which there is no obvious strabismus yet, but eyeballs already tend to deviate from parallel axes.

According to the materials from which the lenses are made:

mineral glass;
plastics.

By light transmission:

transparent;
colored (sun protection);
photochromic (changing color depending on lighting).

By the number of optical zones in the lens:

single vision;
bi- and trifocal;
progressive or multifocal - change their focus depending on the distance to the object in question.

Reasons

Indications for spectacle correction:

myopia (myopia) - a violation of refraction (the process of refraction of light rays in the optical system of the eye), when light is focused not on the retina (the inner layer of the eye), but in front of it - a person sees well near, blurred into the distance;
hyperopia (farsightedness) - a refractive error in which light falls not on the retina, but behind it - a person sees blurry near, well - in the distance (with a high degree of hyperopia, the patient sees poorly both near and far);
astigmatism (impaired sphericity of the eye) - with this refractive error, light is focused not in one place of the retina, but in several - astigmatists have visual impairment both near and far;
presbyopia - age change vision associated with clouding of the lens (the clear biological lens of the eye), people with presbyopia have blurry vision up close;
childhood(up to 13 years old);
amblyopia (poor vision, more often in one eye);
anisometropia is a condition when different eyes different types and/or degree of refraction;
heterophoria (hidden strabismus) - a condition in which there is no obvious strabismus yet, but the eyeballs already tend to deviate from parallel axes;
individual intolerance to contact lenses;
inability to carry out surgical correction visual impairment.

Contraindications to spectacle correction:

infancy;
some mental illnesses;
professions related to necessity wide field vision and increased concentration (for example, pilots, firefighters);
anisometropia - if the difference in refraction in the eyes is more than 2 diopters (refraction measurement units);
individual intolerance to glasses.

Pros of spectacle correction:

accessibility (wide range of assortment, both in design and price category);
ease of use;
reversibility of the effect;
lack of an alternative (under 13 years of age or individual intolerance to contact lenses).

Disadvantages of spectacle correction:

incomplete vision correction - as a rule, glasses are selected in such a way that complete correction does not occur. This is done to avoid the development of lazy eye syndrome;
a foreign object on the face - glasses get dirty, fog up, may slip or fall, the cosmetic effect is important - a change in the perception of the shape of the face when wearing glasses;
injury risk - when playing active sports or, for example, falling, glasses can cause eye injury;
Incorrectly chosen glasses can make you feel worse or contribute to further deterioration of your vision.

Diagnostics

Examination by an ophthalmologist.
Visometry is a method of determining visual acuity using special tables. In Russia, the Sivtsev-Golovin tables are most often used; the letters are written on these tables different sizes, larger ones at the top, smaller ones at the bottom. With 100% vision, a person sees the 10th line from a distance of 5 meters. There are similar tables, where instead of letters there are rings, with breaks on a certain side. The person must indicate which side the gap is on (top, bottom, right, left).
Automatic refractometry is a study of the refraction of the eye (determining the point of the ideal image relative to the retina) using a special medical device - an automatic refractometer.
Cycloplegia is a drug-induced shutdown of the accommodative muscle of the eye in order to detect false myopia. A person with normal vision will experience “physiological” myopia caused by spasm ciliary muscle. If myopia after cycloplegia decreases but does not disappear, then this residual myopia is permanent and requires correction.
Ophthalmometry - measurement of the radii of curvature and refractive power of the cornea (the transparent membrane of the eye).
Ultrasound biometrics (USB), or A-scan - ultrasound examination anterior segment eyes. The technique presents the obtained data in the form of a one-dimensional image, which allows one to estimate the distance to the boundary of media (organism structures) with different acoustic (sound) resistance. Allows you to assess the condition of the anterior chamber of the eye, cornea, lens, and determine the length of the anterior-posterior axis of the eyeballs.
Pachymetry is an ultrasound examination of the thickness of the cornea of the eye.
Biomicroscopy of the eye is a diagnostic method using a slit lamp - a special ophthalmological microscope combined with a lighting device.
Skiascopy is a method for determining the refraction of the eye, based on observing the movement of shadows in the pupil area when the eye is illuminated by light reflected from a mirror.
Vision test using a phoropter - determination of refraction using a special device - a phoropter.
Ophthalmoscopy is an examination of the fundus of the eye using a special mirror - an ophthalmoscope. Easy to implement, but very informative research. Allows you to assess the condition of the retina, disc optic nerve, vessels of the fundus.
Selection of suitable glasses (lenses).

Additionally

Glasses allow various violations vision to focus light rays on the retina (the inner layer of the eye, the main function of which is to transform light rays into nerve impulses, with the help of which the brain recognizes surrounding objects), allowing you to get a clear and clear image of surrounding objects. Glasses can also protect your eyes from aggressive influences environment- strong wind, dust, sun rays etc.
Spectacle correction visual acuity impairment is one of the oldest and most accessible. The first glasses appeared in the 15th century and became widespread due to their ease of use and good results in correcting visual impairment.
Most people with impaired visual acuity use glasses correction.

Spectacle vision correction is a method of correcting vision using glasses. Products were invented in Italy in the 13th century.

IN modern society this is one of the most common correction methods: according to WHO about 30 percent The world's population has vision problems, and most of these people choose glasses.

Optical vision correction: what it is, how it happens

The essence of vision correction is that it corrects the optics of the eye, and light is focused on the retina.

In myopic people the image is created not on the retina, but in front of it, and therefore they see distant objects unclearly.

They need glasses with diverging lenses, through which light rays will be focused precisely on the retina, creating a clear image.

In farsighted people On the contrary, the eyes create an image behind the retina. And that's why they need collecting lenses.

It turns out that the lenses in glasses change the length of light rays so so that light is focused on the retina, thereby helping people with visual impairments to see clearly the world around us.

Indications

Spectacle vision correction is the correction of visual impairment using a special device - glasses. They are frames and lenses. A lens is an optical transparent body that refracts light rays.

Indications for the use of spectacle optics:

myopia(myopia) up to -30 diopters;
hypermetropia(farsightedness) up to +10 diopters;
all types of complex and mixed astigmatism(impaired eye sphericity) up to +/- 6 diopters;

heterophoria(hidden strabismus);
presbyopia(age-related farsightedness);
aniseikonia(a condition of the eye in which the sizes of visible objects are perceived with a significant difference);
childhood up to 13 years old;
amblyopia(low vision, often one eye);
anisometropia(with a refraction difference of no more than 2 dioptres);
lack of opportunity to undergo surgery or laser correction visual impairment due to contraindications or other reasons.

There are no significant contraindications. Unless glasses cannot be used in infancy, for certain mental illness and with individual intolerance. Glasses are also not suitable for people whose professional activities require a wide field of vision or take place in smoky rooms.

Types of spectacle lenses and their corrective orientation

Lenses are divided according to their shape: their correctional focus depends on this.

Spherical

One of the surfaces (or both) of these lenses is spherical. They are used for both myopia and farsightedness. In the first case, the surface is concave, and the lenses themselves are divergent. In the second version, the lenses are positive (or collective).

Photo 1. This is what a checkered piece of paper looks like when looking at it through a spherical (left) and aspherical (right) lens.

Cylindrical

This type of lens, one (or both) of the surfaces of which is cylindrical, used to correct astigmatism. In this disorder, light is focused both behind and in front of the retina. A cylindrical lens corrects this problem.

Prismatic

Glasses with prismatic lenses are prescribed with heterophoria.

In addition to the shape, lenses vary in thickness. Depending on the value of the refractive index, lenses are divided into mid-index, high-index, ultra-high-index And standard refractive index lenses. The higher the index, the smaller the thickness and the less obvious the prismatic effect of the peripheral part spectacle glass.

Photo 2. The structure of a prismatic lens. It is a crescent thickened on one side.

Methods for diagnosing vision and selecting glasses

Before selecting products, the ophthalmologist conducts a number of studies:

determines visual acuity each eye;
conducts automatic refractometry;
determines the degree and type of ametropia based on a subjective method (determining maximum visual acuity using spectacle correction);
clarifies maximum visual acuity under diaphragm conditions;
conducts a trial wearing of spectacle optics within half an hour.

Children and people with amblyopia are also treated drug-induced cycloplegia to turn off accommodation and determine the degree and type of ametropia using subjective and objective methods.

Having completed the examination, the doctor issues a prescription with the required optical power of cylindrical or spherical lenses, interpupillary distance and the reason for selecting glasses.

Well-chosen glasses provide high visual acuity, full binocular vision functions, refractive balance, good tolerability and visual comfort.

Attention! Once a year You will need to undergo a new examination by an ophthalmologist to make sure that the glasses you are using are still suitable.

Pros and cons of wearing glasses, effectiveness of correction

Glasses have many advantages:

Their main advantage is accessibility. It is not difficult to purchase glasses with the required diopters and lens shapes even in the most remote corners of the country.
They are very easy to use. There is no addiction, no need to remember the rules of use.
If you don’t like the correction method with glasses, then There is always the opportunity to choose a more suitable option.
Products are suitable for children under 13 years of age, who, due to their age, have few correction options.

This method has the following disadvantages:

Glasses do not provide complete vision correction.
They limit peripheral vision, disrupt the stereoscopic effect and spatial perception.
Glasses, unlike soft lenses, are less convenient to use: they fog up, slide off the nose, and interfere with active sports.
Incorrectly selected optics affects your well-being: she can simply call headache, and can cause further deterioration of vision.

How to use black perforated glasses products?

Perforation glasses - products with lenses made of dark plastic with holes in them, arranged in a pseudo-chessboard order. Because of their structure, they provide the person using them with eye muscle training: the gaze automatically focuses, trying to see the object through the holes.

Indications and contraindications

with heavy eye strain, for example, people whose professional activities involve working on a computer;
for short-term correction myopia, hypermetropia, astigmatism;
for short-term vision correction with various opacities of the optical media of the eye (for example, initial stage cataracts or superficial corneal opacities);
with increased photophobia.

They have a number of contraindications:

glaucoma(disease caused by increased intraocular pressure);
nystagmus(involuntary oscillatory eye movements of high frequency).

Before use, consult an ophthalmologist:

for retinal diseases eyes;
with progressive myopia.

Appearance of optics

Perforated glasses consist of a metal or plastic frame into which thick black plastic plates are inserted instead of lenses. 1.2-1.5 millimeters with many holes diameter 1.2-1.5 millimeters. The number of the latter is not standardized and depends on the size of the plates.

Photo 3. Perforation glasses. They are a frame with black opaque lenses, in which there are many holes.

The holes are cone-shaped and arranged in a hexagonal pattern: the horizontal distance between their centers is 3 millimeters, and diagonally - 3.5 millimeters.

Reference. Some glasses models have cutout at the bottom of the lens: he allows myopic people see up close.

Impact principle

A person wearing glasses with holes multiple images are focused on the retina of the eye. To make the image clearer, the ciliary muscles of the eye change the curvature of the lens. Thus, the muscles work every time the gaze moves from one object to another.

This is a device Provides continuous training to unused eye muscles, while simultaneously relaxing those who are overstressed. Wearing glasses not only trains muscles, but also improves metabolism in the tissues of the eye, slows down the process of loss of elasticity of the lens, thereby preventing cataracts and other eye diseases.

Clinical refraction is determined by the position of the focus at which parallel rays are collected relative to the retina. With normal refraction (emmetropia), the focus is located on the retina, and with abnormal refraction (ametropia) - myopia, farsightedness - outside it, which leads to a decrease in visual acuity.

There are several methods for correcting ametropia. They all boil down to changing the direction of rays entering the eye so that they are focused on the retina. The most common way is to use glasses. Contact lenses, which are widely used at present, are the same glasses worn directly on the cornea of the eye. Surgical methods have also been developed to correct abnormal refraction. All these methods are effective only in cases where there are no other reasons for decreased visual acuity, that is, the optical media are transparent, the retina is normal.

Correction of farsightedness (hyperopia)

The refractive apparatus of the hypermetropic eye is weak relative to the length of the optical axis of the eye. The focus is behind the eye. With slight farsightedness, thanks to accommodation (the lens increases its curvature and enhances the refractive power of the system), most people see well. In cases where the force of accommodation is not enough or constant tension tires the eye, vision correction with glasses is indicated. A converging (“plus”) lens is placed in front of the eye. After it, partially collected rays enter the eye, which, as a result of passing through the refractive apparatus of the eye, are now focused on the retina.

At the same time, the power of glasses (in diopters) is not always equal to the degree of farsightedness (especially since such glasses are not always well tolerated). For young people, it is enough to correct part of the hypermetropia: the rest will be taken over by accommodation. The main thing is good visual acuity and the absence of eye fatigue.

A special case is farsightedness in children. People are usually born farsighted. As the eye grows, farsightedness decreases, and by the age of 11-12, refraction becomes normal. If the child's visual acuity is good at distance and near, such farsightedness does not require correction. But in some cases, the constant tension of accommodation leads to its so-called spasm, a persistent decrease in vision, and strabismus may develop. The squinting eye is not involved in binocular vision and loses the habit of looking. It reduces vision and cannot be corrected with glasses (so-called amblyopia from inactivity). To avoid this, you need to put on glasses in a timely manner and wear them constantly.

Age-related farsightedness - presbyopia occurs due to the fact that after 40 years the eye gradually loses its ability to accommodate (with very rare exceptions), and after 60 years this ability disappears completely. Distance vision does not change, but near vision deteriorates. As a rule, for a forty-year-old person who previously had normal vision, glasses with a power of +1.0 diopter (D) become necessary for near vision. Then every 5 years +0.5D is added. Over 60 years of age will require glasses with a power of +3.0D. It often happens that normally sighted people under 45 years of age still do without glasses or require weak glasses. But in the future, these calculations become applicable to them. Therefore, drivers whose age is approaching 40 years, and even more so has exceeded this mark, should periodically visit an ophthalmologist for timely selection of corrective glasses of the required strength.

If a person uses distance glasses, then their power is added to the power of presbyopic glasses according to algebraic rule. Examples of such calculations:

45 years old, myopia 5.0D. Near glasses: (+1.5D for age) + (-5.0D for myopia) = -3.5D.
50 years old, farsightedness 3.0D. Near glasses: (+2.0D for age) + (+3.0D for farsightedness) = +5.0D.
60 years old, myopia 1.5D. Near glasses: (+3.0D for age) + (-1.5D for myopia) = +1.5D.
60 years old, myopia 3.0D. Near glasses: (+3.0D for age) + (-3.0D for myopia) = 0.0D (that is, reading glasses are not needed).

It's good to know that if people who use near glasses suddenly have better vision, it's not a happy occasion: cataracts may be developing. A visit to an ophthalmologist is necessary! The reverse case is even more a serious signal: the development of presbyopia before 40 years of age or the need for stronger glasses than required for age makes one suspect the occurrence serious illness- glaucoma, which requires early detection and treatment.

Correction of myopia (myopia)

The refractive apparatus of the eye is too strong, the focus is located in front of the retina. The eye sees objects well at a more or less close distance (from which diverging rays come), but distance visual acuity is always reduced. To correct distance vision, a diverging (“negative”) lens is placed in front of the eye.

Myopia can develop with slight congenital farsightedness as the eye grows. Congenital myopia can reach high degrees during growth. Typically, the increase in eye size ends by the age of 20-25, and the myopia formed by this time remains, as a rule, for life. But there are cases when the growth of myopia continues and reaches very high degrees - up to 20-30 diopters. Such myopia is already a disease and is accompanied by pathological changes choroid and retina associated with stretching of the posterior segment of the eye. It can be complicated by retinal hemorrhages and retinal detachment and requires systematic treatment. Visual acuity with such myopia decreases sharply and is difficult to correct.

The need to constantly wear glasses is determined by the degree of myopia. With slight myopia, constant wearing of glasses is not necessary. They can be used when you need to look into the distance. High myopia forces you to wear glasses all the time. With divergent strabismus, which sometimes develops in nearsighted children, constant wearing of glasses is mandatory.

Myopic people usually have poor accommodation, so using a full correction that forces the eye to accommodate when working near can tire it and contribute to the increase in myopia. In addition, strong negative glasses reduce the apparent size of the object. This leads to practical advice: when working with closely located objects (reading, writing, sewing, etc.), you need to focus on how clearly the small print is visible approximately 40 centimeters from the eye. It is recommended to either work without glasses at all, or use the minimum correction that allows the eye to see well at the specified distance. That is, to have special “weak” glasses, “reading glasses” for working near. When driving a car, it is mandatory to wear glasses that provide complete correction of myopia (the so-called “distance glasses”). However, in some cases, if the volume of accommodation is not reduced, it is allowed to use distance glasses when working with close objects.

Currently, many people have a variety of vision problems. To perform high-quality vision correction, you will need glasses. In order for this device to perform high-quality correction, you will need to select glasses for your vision.

Choosing the right glasses for your vision

In this article, we tried to tell you how to choose glasses for your vision and told you all the details. After contacting an ophthalmologist, he will use special equipment that will help you select quality products.

Visual acuity test

To select the correct glasses for your vision, you first need to determine the acuity. An autorefractometer will help you choose the optimal visual acuity indicators. It is not recommended to trust everything to the computer. An additional check must be carried out by a specialist.

Important to know! Order glasses only based on results computer research unacceptable.

You can also check your visual acuity using a table or using a special sign projector from a distance of 5m. Each eye must be tested individually. You need to start choosing glasses for vision from the right eye.

Then, using a special frame, specialists attach plus or minus lenses. The selection of glasses for vision in this case will depend on the indicators of the autorefractometer.

Visual acuity – important parameter when choosing glasses

It is necessary to select lenses only sequentially. If you have a problem of myopia, then a lens is prescribed that will have minimal refractive power. In case of farsightedness, on the contrary, a lens with maximum performance will be selected. Visual acuity of both eyes in mandatory should be 0.9-1.0.

Sometimes you may encounter a problem when the vision of the right and left eyes is different. The maximum permissible difference in diopters should in no case exceed 2-3 D. In this case, everything will depend on the patient’s individual tolerance. If a person has problems with myopia and farsightedness, then he may be prescribed.

Correction of astigmatism

The most difficult task for every specialist is the selection of correction for astigmatism. The main difficulty is that it takes some getting used to. Accordingly, with high degrees of astigmatism, you may be prescribed weak lenses, and then their effect will gradually increase. Instead of a trial frame, a special attachment to an ophthalmological diagnostic complex – a phoropter – can be used.

Selection of astigmatism correction

When selecting glasses for vision, ophthalmologists use a special table to test near vision. The selection will be carried out according to the same rules as for the distance. If the patient wishes to be fitted with bifocal glasses, then vision will be tested for both distance and near vision. The optical power in this case should not exceed 2-3 D. Where can I get my eyes checked and choose glasses? This is a common question that almost every patient asks himself. Ophthalmologists or specialized centers where the sale takes place.

Measuring pupillary distance

After selecting the correction, specialists will begin to measure the interpupillary distance. Usually the distance is measured using a regular ruler. Naturally, today there is a certain technique that allows you to measure the distance between the pupils. As a rule, the distance at distance will be 2 mm greater than at near.

Determination of interpupillary distance

Glasses prescription

After checking all the necessary indicators, the ophthalmologist or optometrist will write a prescription, which will indicate:

Patient data.
Optical power of optical or cylindrical lenses.
Purpose of assigning points.

Optotypes are special tables that depict various symbols

In some cases, specialists may also indicate additional indicators. It is not recommended to throw away all prescriptions prescribed by a specialist. They are necessary so that in the future you can take a prescription and see how your vision has changed over a certain period. Incorrectly selected glasses can cause a number of problems, so before choosing, consult only real professionals.

The price of a mistake

Sometimes you can encounter a problem when the choice of glasses for vision was made completely wrong. If you encounter a similar problem and continue to use glasses for vision, then the process of addiction will gradually begin. As a result, the body will try to compensate for optical distortions at the cost of eye fatigue. Accordingly, after just a few days of using such glasses, you may notice a headache, as well as further deterioration of vision.

Now you know exactly how to choose glasses for your vision. This process will not be difficult if you carefully study all the recommendations of specialists. We hope that this information was really useful and interesting.