The normal lifespan of discountglasses lenses generally does not exceed two years. Do not let lenses exceed their service life, as there may be potential visual fatigue.

The optical performance of lenses that are maintained normally every day can only last for about 2 years. So, how long do you think the best optical writing performance of glasses that you "ravage" every day can last?

Teach you a very simple way to determine whether the optical performance of the lens is maintained well. At night, you can carefully observe the roadside street lights, preferably at every angle of the lens. If the light of the street lights appears to have stray lights or regular strip-shaped lights, it means that there are scratches or oil stains on the lens, and the lens is already "unqualified".

The lenses are more delicate than you imagine, and any throw could leave a mark. Take good care of discountglasses.

The leg of the right mirror is extended outward, and the right lens is more closely attached to the face when worn. The effective degree of myopia with the right lens is relatively high. The left lens is far away from the face, and the effective myopia degree of the left lens.

It may lead to overcorrection of the right lens, adjustment of the viewing distance, tension and protrusion of the lens, and pulling it back to the retina, but still clear. The clarity of the left eye may decrease, resulting in an imbalance of binocular clarity.

Up close, the regulation of the eyes is different, and it is controlled by one neuron, which can only produce one regulation. So a smaller adjustment was used for the left eye, and the adjustment for the right eye was insufficient, resulting in defocusing and degree dilation. It is necessary to develop a good habit of taking off and wearing discountglasses with both hands.