Good lighting conditions may cause myopia

We repeatedly stressed to protect children's eyesight, its main measure is to improve the classroom, library of lighting. Parents give children buy best desk lamp, but also improve the nutrition, the result is myopia more and more.

in more than 30 years ago, primary and middle school students wear glasses is very few, especially in the countryside, glasses is very rare. Today, is still a little boy wearing glasses in the country. Statistics say, city myopia 4 ~ 5 times that of rural proportion of middle school students.

myopic children in the city, one of the reasons is the lighting good

when analyzing rural children myopia is little, a lot of people come down to learning, reading time is short, work pressure is small. Of course, that is why on the one hand. However, when those studying under the oil lamp for many years, why after college, night lighting condition improved, but wearing glasses? A few years ago, listen to a from rural areas to the old man said, the city myopia more because the lamp is too bright. At that time, I just think it makes sense, but say not clear why.

once upon a time, we emphasized to protect children's eyesight, its main measure is to improve the classroom, library of lighting. Parents give children buy best desk lamp, but also improve the nutrition, the result is myopia more and more. Now we know, desk lamp is eyesight killer. The rural old man right, myopic children in the city, one of the reasons is too good lighting conditions. Why

in the case of lighting darker, it is not easy to myopia?

let's see why myopia. When near vision object, if without adjustment, object imaging in the retina, of course, can't see clearly. This normally through the ciliary muscle contraction, let the lens diopter increasing, can make the object image onto the retina, can see clearly now. However, for a long time to see near objects, frequent ciliary muscle contraction, can not get rest, will lead to longer on eyeball diameter before and after. So, don't need the ciliary muscle contraction, the object can image on the retina, let a person see close objects easily. However, axial elongation, see distant objects, imaging in front of the retina, eye muscle fail to adjust, and only by wearing glasses to correct his eyes diopter, lets distant objects imaging in the retina. Thus, myopic eye axis is the nature of adaptive response of near vision in the long run. The elongation generally cannot be reversed, or no reverse conditions, such as no man can be a long time not to engage in close work and studies, etc.

why when the light is dark but not easy to myopia? There is a phenomenon called night myopia, is the clear vision during the day, but at night need to wear myopia glasses. Investigate its reason, is the night with the difference of refractive, vision imaging before.

there are experiments have proved that feeding the monkeys in the dark in the house, can lead to the monkey farsightedness. So, see things in more dark light, compared with the vision under the desk lamp of bright, light is dark when the object imaging before, after partial bright light. So, the light is bright, natural axial elongation of stronger adaptive reaction.

how to prevent myopia?

in the first place, family lighting shoulds not be too bright. Children's books, homework handwriting is compared commonly big, see clearly should not be a problem. In addition, study at night after a period of time, want to play outside. In dark light activity, it is good for your eyesight. In the worst case is under a bright lamp, attached to a few days to stay up late to read novels, before a few days, so will not wear glasses.

coordinating editor li jie

sina health blog