Causes of dizziness when wearing glasses
Prism degree exceeded
Prism is the distance from the lens to the object, 100 times the lens power of the image point on the object, that is, the ratio of the deviation distance of the imaging point to the distance from the object to the lens is expressed in cm/m, including two indicators: the pair of lenses is perpendicular to the meridian The difference does not exceed 0.25cm/m, and the difference between the horizontal meridian does not exceed 0.75 cm/m: If any index of the two lenses of a pair of glasses exceeds this standard, it will make people feel that the eyes are swollen.
Sphericality exceeded
Sphericity is the average of the optical powers of the two main meridians of the lens ︱D1+D2︱÷2. The standard is within ±0.12mm. If it exceeds this standard, people will feel dizzy.
Excessive astigmatism
Astigmatism is the absolute difference of the optical power of the two main meridians of the lens ︱D1-D2︱, the standard should be greater than 0.12mm, if it exceeds this standard, people will feel dizzy. Because the above three indicators of lenses with 6 bends (abbreviated as 6C) are relatively stable and not easy to exceed the standard, the optical processing difficulty will increase exponentially if the lens exceeds 6C. Curvature refers to the curvature of the lens above 8C.
