Цифровая эпоха, которая уверенно шествует по planet, 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 force 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 having a certain unit in terms of its 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, removed by a unit of distance, after they cross a convex lens.
Such a natural lens in the eye of a personis a lens and other translucent media, it is able to change its size, and depending on the strength of its optical power is from 57-59 to 70-70.5 m-1 (this is the diopter).What does this mean in practice? The natural lens of the eye performs the focusing of 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 imaging 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 for the formation of the image, and it is formed behind the projection screen of the eye - the retina.
In this case, a reasonable solution will beto the ophthalmologist who will be able to examine the fundus and select the necessary accessory in accordance with your eyesight, the dioptre table is used for diagnosis by specialists. It reflects the relationship between changes in the eye and the refractive power of glasses. To do this, we use lenses with the necessary values that scatter or focus, 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 the diopter). 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 choose 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.
After the survey, the owner will be able to comfortably andIt is safe to 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 reduce the force of the lens by 0.5-1 m-1in this case, the eyes will not become excessively tired or degraded by idleness. After all, keeping your sharp-witted friends in good shape is a guarantee of the health of your eyesight as a whole.
