Diopter, what is it? What is its effect on vision?

The digital age, which confidently marches the planet, has led to the fact that mankind began to work with objects in the immediate vicinity of them. A computer, a digitizer or even an exact instrument forces our eyes to function exclusively in one mode, which is not strictly foreseen by nature, and they may need correction. Usually it is made with the help of contact lenses or glasses that have a certain unit in terms of their optical power. It is called "diopter". What this value measures, it is not difficult to find out. The ability to focus rays of light at a single point, separated by a unit of distance, after they cross a convex lens.

A natural eye loupe

Such a natural lens in the human eye is the lens and other translucent media, it is capable of changing its dimensions, and depending on the intensity, its optical power is from 57-59 to 70-70.5 m ^-1 (so denoted diopter). What does this mean in practice? The natural lens of the eye focuses the rays at a distance from 1/57 to 1 / 70.5 meters due to a change in the curvature and lens size, it produces an image on the retina. If the size of the eyeball is enlarged or reduced in the longitudinal direction, this leads to an incorrect display. In the first case, called myopia, because of the increased distance, focusing occurs earlier than necessary. In the second, everything is diametrically opposite: the hypermetropia of the eye causes insufficient space to form an image, and it is formed behind the projection screen of the eye - the retina.

Selection of means of vision correction

In this case, a reasonable solution will be an appeal to an ophthalmologist who will be able to examine the fundus and select the necessary accessory in accordance with your eyesight, for diagnostics specialists apply the diopter table. It reflects the relationship between changes in the eye and the refractive power of glasses. For this purpose, lenses with the necessary values, scattering or focusing, are used, and according to the Sivtsev table the necessary positive or negative value of the optical power of the lens is determined (its measure is determined by dioptry). What does this give the patient? He can now clearly monitor the meaning of his "plus" or "minus" and always get advice and necessary adjustments. But the use of contact lenses or glasses helps not only improve the ability of the eye to focus (for example, -1 diopter). What is important is not in doubt. You can also use colored contact lenses to change the appearance or glasses with conventional glasses and expensive rim to look older. But you should not opt for optics yourself, even as an accessory, because there are many parameters, for example, the radius of curvature of the lens, the transmitted light flux, protection from ultraviolet and other conditions, the measurement of which is performed only by specialists. After the examinations, the owner can comfortably and safely wear glasses or contact lenses.

Healthy eyes without complaints

After the examinations, the owner can comfortably and safely wear glasses or contact lenses. With a small deviation of vision from the norm ± 1 dioptric optics may not be required. But if the values are greater, it is better to lower the power of the lens by 0.5-1 m ^-1 , in which case the eyes will not excessively fatigue or degrade from idleness. After all, maintaining your sharp-sighted friends in a tone is the guarantee of a healthy eye in general.