Myopia are often divided into mild myopia (≤300 degrees), moderate myopia (300 degrees to 600 degrees) and high myopia (›600 degrees).

What are the causes of myopia?

1.Genetic factors

Some people are born with too long axial length, and that they are short-sighted at birth.

This might be related to the myopia of the parents.

Some studies have shown that if one among the parents has myopia of more than 600 degrees, the probability of passing it on to the subsequent generation is about 20%.

If both are myopic, the subsequent generation is shortsighted.

The speed is as high as 40%.

So for the subsequent generation's eye health and reduce the chance of myopia, please protect our eyes.

2.Light factor

"The dim light is emitted from the mobile , and therefore the small characters on the mobile phone are densely packed, and you'll stare at it for several hours."

"The bright light is sweet , and therefore the brightest adjustment is made, otherwise the writing are going to be difficult to read."

When the sunshine is too weak, so as to see Clearly, by holding things too close, the ciliary muscles enter tense mode.

Too strong light illuminates the pupil, which can shrink the pupil and tighten the ciliary muscle.

The crystal wants to vary to a flat position, but it's tightly restricted by the ciliary muscle, and myopia involves the door.

3.Bad posture

Some people wish to lie down, play with mobile phones or read books.

How comfortable the posture is, no matter the feeling of the eyes, it'll keep the ciliary muscle in a tight state for a long time.

Myopia isn't far from us.

4.Insufficient eye relaxation

Everyone likes to relax ahead of electronic products at night.

It takes an entire night to watch dramas or play games.

There's absolutely no time and opportunity for eyes to relax.

To relax, the ultimate outcome is also myopia.

5.Vitamin deficiency

Vitamin B1 is an optic nerve nutrient.

If vitamin B1 is lacking for a long time, it'll cause vision loss due to insufficient eyeball nutrition.

6.Lack of calcium

Calcium is that the "protector" of the eyes.

If calcium is deficient, the ciliary muscle will lose its elasticity, which may easily lead to myopia in our eyes.

Myopia glasses are concave lenses.

Myopia is primarily thanks to a deformation of the lens (thickening of the lens), which causes light to gather prematurely in front of the retina.

The diverging lens plays the role of diverging light.

The diverging lens forms an upright, shrinking reflection, which makes the image distance longer and just falls on the retina.

Therefore, concave lenses are mainly wont to correct myopia.

The hyperopia lens uses a converging lens, because the lens of hyperopia is just too thin, and therefore the image is formed behind the retina, and therefore the convex lens has a converging effect on the light.

After proper adjustment, the formed image can fall on the retina.

If a toddler is short-sighted without appropriate glasses, if the eyes are always during a state of blurred things and the eyes are not stimulated by enough light, the event of the visual function of the eyes will be hindered, leading to low vision, even after adulthood, correct vision, Vision isn't particularly good, and it's difficult to improve vision even with LASIK surgery.