What is nearsightedness

Nearsightedness or nearsighted eye is also callednearsighted.
myopia. Nearsightedness is self-explanatory in its 
definition. It is a refractive defect of the eye inNearsightedness can be determined by eye
which in which nearsighted people can see nearbyexam, measuring in diopters by the strength, and
object clearly but have difficulty in reading andthe prescription is a negative number, the higher
seeing objects at a distance. We know the humanthe number is the worse the eye's condition is.
being's eyes have the ability of focusing images ofNearsightedness is divided into three levels by the
both nearby and distant objects, because the lensnumber, low myopia (0.00 to -3.00 diopters),
of the eyes can assume a large curvature tomedium myopia (-3.00 to -6.00 diopters) and high
focus nearby objects and a flatter shape to bringmyopia (-6.00 to -10.00 diopters). Nearsightedness
a distant object into focus. When the eyes arecan also be divided into simple myopia,
not able to provide a long focal length they can'tdegenerative myopia, nocturnal myopia,
focus on distant objects, so nearsightednesspseudomyopia and induced myopia by their clinical
occurred. Nearsighted problem is very common inappearance. Fortunately, nearsighted eye can be
youth. It is said that 1/3 of the population iscorrected by eyeglasses or contact lenses simply.
nearsighted. Bad behaviors such as sitting close toIf glasses or contact lenses are not favorable,
the television while watching TV, holding booksnearsighted people can choose refractive surgery,
very near to the face, reading in sun or in a bussuch as LASIK and PRK, in which a flap is cut
can lead to nearsightedness. Some evidencethrough the top of the cornea by an excimer
suggests that if one or both parents arelaser.
nearsighted, their children are more likely to be