Sunglasses are not the higher the degree of absorption the better
Date:2022.11.29 Views:339
1、Sunglasses
Transparent material if it is colored, can absorb light; people consciously add color to the lens, can absorb a certain wavelength or a certain color of light, if it is full wavelength absorption, add gray, uniform absorption of various wavelengths of light, when the gray concentration is very close to black, is commonly known as sunglasses. General sunglasses absorb 30%-70% of the visible light, the concentration can be adjusted at will.
2, polarized lenses
Polarized lens is a special sunglasses, is based on the principle of polarization of light manufactured lenses, can exclude and filter the light beam in the scattered light, anti-UV and filter polarized light.
The light seen in nature is basically uniform and comfortable for the eyes to see, but when the light waves are particularly strong in a certain direction during the conduction process, they will be transmitted to the eyes with the feeling of dazzling light, i.e. polarized light. The most harsh is the horizontal polarized light, rain on the road, the lake have this kind of light, it is reflected after the horizontal band of light is particularly strong, and polarized light sheet like a fence, can be shielded from the light.
3, sunglasses are not the higher the absorption degree is better
The current process is very sophisticated, glasses on the visible light absorption degree can be freely controlled according to the requirements. So how should you choose the degree of absorption of the lens? Need to choose the degree of absorption of visible light according to the strength of the protection object.
If it is extremely strong light, such as watching the solar eclipse, sunglasses need to reach 80-90% absorption of visible light.
If it is swimming at the beach, then sunglasses need to absorb 50-60 percent of visible light.
If you do some common outdoor activities, such as shopping, the absorption of visible light by sunglasses should only reach 20-30%.
In terms of ophthalmology, the higher the absorption of the lens, the worse the vision, the more difficult it is to see things, in the safe range of light, the lower the absorption the better, more beautiful.
4, refractive error with sunglasses there are 2 ways
The presence of myopia, hyperopia, astigmatism and other refractive errors can also wear sunglasses, the following two options.
1, you can add the appropriate degree for the lenses in the order of sunglasses through the optometry, with the premise of prescription. It is also possible to dye the lenses in different shades according to the shade requirements and then replace them in the glasses to match a sunglass with degrees.
2, in the case of colorless corrective glasses, you can wear sunglasses clip-on lenses, which can effectively prevent glare and UV rays. The lens is specially added film reinforced processing, effective degree of resistance to wear and tear, scratch resistance, impact resistance. Sunglasses clip-on can be put on or taken off at any time, very convenient.
5, colored sunglasses easy to see fatigue
Color sunglasses are inconsistent with the filtering of light, some kind of light may come in especially, easy to produce visual fatigue.
