In order to make the optical center distance of the lens and the pupil distance of both eyes consistent, so that the wearer can wear comfortably. According to the national standard for fitting glasses, the center of shift is still acceptable within a certain range.
If the optical center of the lens distance and the pupil distance does not match, through the lens to see the scene will be deformed, distortion, fuzzy, that is, the so-called prismatic effect, the eye is very harmful. Similarly, inappropriate pupil distance of the lens will cause dizziness and nausea, of course, the frame is not suitable to directly affect the position of the lens, will also cause visual fatigue, eye damage.
Because the pupil distance of the lenses of the large frame glasses has a deviation from the pupil distance of both eyes of the person, the pupil distance of the person wearing such glasses will cause the pupil and the center of the lens to focus on the deviation, resulting in blurred vision, visual fatigue, easy to cause myopia.
Extended information:
Precautions:
1, the first time to do dilation of pupils, dilation of pupils and then optometry, dilation of pupils and optometry, but also to do a re-test to determine the degree of myopia, and at the same time, will do a number of simple checks of visual function, such as checking the two eyes are balanced, eye position is not a problem, and so on.
2, choose to receive formal medical optometry professional training of optometrists, for the child rapid pupil dilation point takes 20-30 minutes, closed eyes at least 15 minutes, vision needs 10 minutes. A child vision takes at least 50 minutes to an hour.
3, choose the right lenses, students choose white lenses, office workers to face the computer for a long time it is best to choose anti-blue light lenses.
4, eyeglasses frame can not just look good or not, the key is to choose the right frame and pupil distance.
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