What is the refractive error?

refractive error is a disorder that disrupts the ability of the eye to focus light and causes visual problems. There are a number of different types of refractive errors and can be caused by genetic and environmental causes. These disorders are usually treated by a doctor who specializes in eye care, such as an ophthalmologist, and can be repaired by specialized lenses that compensate for problems with the eye structure. For someone without refractive errors, the focus of light is precisely focused on the retinal interference, generating a sharp and clear image that can be interpreted with cells in the retina, and then transferred to the brain. In myopia or nearsightedness, it is outbreak in front of the retina and forces the person to approach objects to see them more clearly. Hyperopic or forested people have the opposite problem, with a retina's focus, which means they must be away from the objects to see them.

in astigmatism is not the structure of roShit or, resulting in a scattered focus and blurred vision at any distance. People can also develop a type of refractive mistakes known as presbyopia, in which the eye is less flexible over time, making it difficult to read things close.

Using a lens, such as a contact lens or a set of glasses, it is possible to compensate for the refractive error in the eye, causing eye problems. It is also possible to rework someone to make someone who is far -sighted or short -sighted, which is sometimes done intentionally and sometimes sometimes by accident. People can see the effects of overcorection wear a set of glasses with a stronger prescription than their own, or by deploying glasses when they normally wear them.

When an ophthalmologist examines someone with a refractive error, he will come up with a prescription expressed in dioptres that indicate the type of lens. People with nearsightedness need concave lenses that have a negative value such as -1.5, a common prescription, while hyperopian individuals need convex lenses with a positive diopter as+3.