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Why do new glasses not fit?
Sep 11, 2017

In general, there are several situations:

1 Effect of optical center and pupil distance

Under normal circumstances, the light heart distance and pupil distance of the deviation of the better, if the patient in the past glasses of light heart level deviation is very large, degrees and higher, the new mirror according to the standard pupil distance fixed light heart position, after wearing is likely to feel unwell, such as dizziness, the sight of the curved, left and right eye less than a piece, this situation in the larger diopter, the more obvious reaction. Therefore, in order to provide a mirror for customers, we should first measure the size of the gap between the old glasses and pupil distance, for example, a patient's pupil distance of 63mm, the original lens is-4.00, the optical distance is 75mm. And the new glasses with a degree of -5.00D. That is to say, each lens of the optical heart from the corresponding pupil distance error of 6mm, if the new mirror to maintain the original state, the light heart distance should be made 63+ (2. $number) 0? =73mm.

The influence of the tilt of the 2 mirror frame

The tilt of the mirror frame is the angle between the plane normal and the mirror leg. Generally have 6 degrees, 8 degrees, 10 degrees, several specifications. Because of the deformation of spectacle frames in the process of many non-standard spectacle frames and glasses, the effect of inclination size on visual habit is formed. For example, a person who wears the inclination of the body leg is 0 degree glasses, if the new mirror body leg inclination is 10 degrees, even if the degree and the light distance are identical with the original mirror, after wearing the sight thing also may appear dizziness, the upper and lower position is not accurate and so on symptom. Because the position of the glasses leg is mostly connected to the upper part of the lens frame, and because of the gravity effect of the glasses itself, the offset of the optical center position of the glasses is worn. In this case, the inclination of the leg can be adjusted appropriately, so that it is close to the original mirror.

3 influence of the excessive correction

The general requirements of myopia correction of 5.0 can be achieved, excessive correction will attach importance to the eye muscle adjustment, resulting in vision fatigue and diopter further deepened. Therefore, when the original mirror is excessively corrected, corrected eyesight reaches 5.2 or higher, should be adjusted to 5.0 when the new mirror is fitted. So some patients in wearing new glasses will be due to the decrease in diopter and feel unwell, such as the difficulty of seeing things, at this time according to the actual situation and appropriate to the normal state of 5.0.


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