Most sunglasses are designed to shield our eyes from the harmful effects that the sun can have on our eyes. The labels of sunglasses often promise protection against ultraviolet light as well as other types of natural radiation. You must understand the types of light that your eyes can protect against and those that are not.
Blocks 99 % Of Ultraviolet Rays
These features should be included in all sunglasses. Long-term exposure to UV (UV) radiation to sunlight can cause cataracts, eye growths, and even cancer. UVB radiation can be more dangerous for the eyes and skin than UVA radiation.
Both glass and plastic lenses absorb some ultraviolet light. However, UV absorption can both be increased by using chemicals in the manufacturing process or special lens coatings.
Make sure to look for sunglasses which block 99 per cent or 100 per cent of all ultraviolet light. This is the same as 100 per cent UV absorption.
Ground And Polished
Nonprescription glasses may be ground and polished to improve their quality. You won’t get any irritation from nonprescription lenses if they aren’t polished and ground.
You want to be sure the lenses you purchase have been made correctly. For non-prescription sunglasses that are not prescription, you can look at anything with a rectangular pattern (e.g., floor tile) to gauge their quality. Place the glasses at a comfortable distance from one eye. You can slowly move the glasses side-to-side, and then up/down. If the lines are straight, then the lenses are good. If you feel the lines are moving, especially in central areas, get a new pair.
To ensure safety, all sunglasses must meet the Federal Food and Drug Administration’s (FDA) impact standards. There is no perfect lens, but plastic lenses are less likely to be damaged than glass lenses if they are struck with a ball or a stone.
Plastic lenses make up most nonprescription sunglass lense. Although they are extremely tough, polycarbonate sunglasses made from plastic are scratch-resistant and can be used for many other sports. You should look for polycarbonate lenses that have scratch-resistant coatings when you are looking to buy them.
Polarized lenses reduce the reflected glare and sunlight that bounces off shiny surfaces like pavement, car windows or chromed surfaces. They are useful for driving, fishing and other activities.
However, polarization has nothing to do with UV light absorption. Many polarized lenses have been combined with a UV blocker substance. Make sure to check the label for maximum UV protection.
Wraparound glasses prevent light from shining in your eyes through the frames. They are one of Brad Pitt’s best sunglasses styles.
Studies have shown that UV rays penetrate enough into ordinary eyeglass frames to diminish the benefits of protective sunglasses. Protect your eyes from all angles with large-framed wraparound sunglasses
Gradient lenses have a permanent shade from top-to-bottom or top-to-bottom towards the middle. Single gradient lenses (darkening at the top and lighter at the bottom) can help reduce glare in the sky, but also allow you to see below. They can be useful in driving, as they do not dim your view of a dashboard. They won’t be as useful in reducing glare when there is snow or on the beaches.
Double-gradient lens (darkened on the top, bottom and lighter in middle) might be better for sports like skiing and sailing.
Double-gradient lenses should not be used for driving, as they can make your dashboard appear dim.
Mirror finishes are thin layers with various metallic coatings placed on ordinary lenses. Mirror finishes reduce the amount of visible light entering your eye, but they are not guaranteed to protect you from all UV radiation.
Blue light can be harmful to the eyes, but it is still controversial. Lenses that block all visible blue light are typically amber-coloured and cause your surroundings to look yellowish or orange. The tint can make distant objects seem more distinct, especially when there is snow or haze.