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Before taking you should consult with a doctor!
SITE GUIDE ONLY. Not a pharmacy! We do not sell drugs! Nothing!
Refraction
Refractive eye ability, depends on two factors: the strength of the optical system of the eye and the size (length) of the eyeball. The eye is built on the camera type: a light-refracting portion (cornea and lens) and light-sensitive screen (retina).
Light enters through the cornea to the retina, the moisture of the anterior chamber, lens, posterior chamber and vitreous body moisture. Normally, these media are transparent and act as an optical system in which rays are refracted and summarized in the focal point. Clarity of vision depends largely on compliance with the focal point and the retina. If parallel rays of light after refraction converge on the retina, then it obtained a clear image of the object and, accordingly, a high vision. Light rays can converge in front of the retina, called this type of refractive myopia. If the Rays are going to focus behind the retina plane, then this kind of refraction is defined as farsightedness. When myopia and hyperopia image point on the retina will look like a blurry circle. In addition, the appearance of refraction occurs at which point the object is projected onto the retina in the form of strips or ellipse. This is due to the fact that different parts of the cornea or the lens have different refractive power, sometimes even within one meridian. This pathology is called astigmatism.
The cornea has a constant refractive power. The lens can change its curvature, which allows you to clearly see objects that are at different distances from the eye. This ability is called accommodation of, and is lost with age. Disadvantages of refraction are eliminated with the help of corrective glasses (glasses, contact lenses).
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