Refractive index of spectacle lens
It is generally believed that the higher the refractive index, the better the spectacle lens. Such spectacle lenses are relatively thin, and of course, the price is a bit expensive. When the refractive index increases, the direction of the light entering the lens will change greatly, the focus will move to the lens, the focal length will be smaller, and the diopter will become larger. In order to keep the diopter unchanged, it is necessary to reduce the curvature of the lens, that is, to reduce the curvature of the mirror surface, so that the thickness of the lens can be reduced. This is why the larger the refractive index, the thinner the lens is. Under the same premise of other things, the larger the refractive index, the thinner the lens, the lighter and more beautiful the lens, and the higher the price, but the larger the refractive index is not the better.
The surface of the lens is coated with a layer of anti-fogging top film. The anti-fogging function of the lens can be activated by wiping the lens with a professional anti-fogging lens cloth, which can achieve a better anti-fogging effect. Choose this anti-fogging lens and wipe it with the corresponding anti-fogging lens cloth. IT is easy to use, and the anti-fogging effect is ideal, used for a long time. They cannot be wiped and washed.
Orthokeratology lenses are used for myopia control.
The effect of the orthokeratology lens in controlling the increase of myopia in teenagers has been unanimously affirmed by the ophthalmology industry at home and abroad. In February 2006, an authoritative ophthalmological journal published a review of the retarding effect of rigidity breathable orthokeratology lens on the progression of myopia in children. This paper reviews the literature on orthokeratology and myopia in the past 30 years and points out that rigidity breathable orthokeratology can prevent or alleviate the progress of myopia, the mechanism of which is that rigid breathable contact lens can inhibit the progress of myopia by providing clearer retinal image quality. Medium and high concentration of atropine will affect students' near-use vision, while low concentration of atropine has not been used clinically in China, so orthokeratology lens has become one of the known myopia control methods with the best statistical effect. In three to five-year case studies, orthokeratology lenses alleviate a 40 to 60 percent increase in myopia compared with wearing a frame lens or a soft contact lens. Other studies have found that 65 to 70 percent of orthokeratology lens wearers show little or no axial length increase.
Anti-fog lens cloth
Anti-fogging glasses cloth is composed of multiple layers of material pressed together, and the material absorbed a sufficient amount of antifogging agent. It can be directly wiped on any lens. Like spray anti-fogging agents, anti-fogging time is relatively short, and can not be wiped or washed. Long time use will affect the life of the lens. The range of lenses available is limited.
The nose pad
When you're shopping for a driver's glasses, you can't ignore a nose pad. Choose one that is soft and elastic. This way, it won't make your noses feel depressed or uncomfortable.
How To Use Contact Lens Correctly?
Check your eyes for abnormal cases. Do your eyes sting or dry? If so, it is recommended not to wear contact lenses for the time being. Look in the mirror to see both eyes carefully, if it is red and swollen or if is both eyes full of bloodshot? If you do, you can no longer wear contact lenses, and you can go to a professional store for inspection. After putting on the contact lenses, block the left and right eyes respectively to see if the vision of one eye is clear. If the eye vision has decreased or blurred, check if the lens is dirty. If the lens is still the same, you should go to a professional store to find out the reason.
Are progressive lenses good for driving?
Progressive lenses can help you see close, far, and anywhere in between. That means progressive lenses are good for driving. So you don't have to change your glasses on the way. With progressive lenses, you can easily see all distances. Standard lenses are more affordable than premium lenses, but premium lenses offer a wider field of view and are ideal for drivers.