Eye diseases caused by UV are divided into 2 groups: effects from short-term and long-term UV exposure. In the short term… if exposed to high intensity or prolonged UV radiation, it can cause corneal inflammation with symptoms such as burning eyes, tearing, light sensitivity, red eyes, and eye pain. The effects of long-term UV exposure impact both the skin around the eyes and the eyes themselves, such as sunburned skin around the eyes, skin cancer, or if it affects the eye surface, it can cause pterygium and pinguecula. If UV penetrates into the eye, it may cause cataracts or macular degeneration. Of course, sunglasses can help protect the skin around the eyes and the eyes from UV exposure, but they must have appropriate qualities. There are 6 important principles for choosing sunglasses:
- Good UV protection
The U.S. Food and Drug Administration standards specify that standard sunglasses should block at least 95 percent of UVA and at least 99 percent of UVB. To know if sunglasses can block UV, an easy way is to check the inside of the temple arm for the CE mark, which is the European standard certification. - Reduce glare
They should be polarized sunglasses that reduce glare because lenses are made from various materials such as glass or plastic, which can reflect light. Good sunglasses generally reduce glare by about 70-90 percent. - Choose suitable lenses for activities
There are 3 popular types of lenses used for sunglasses: CR 39 lenses are plastic lenses widely used because they resist scratches well and protect against both UV and infrared rays. Glass lenses are clearer and more scratch-resistant than plastic lenses but are heavier and can break in severe accidents. Lastly, polycarbonate plastic lenses are the lightest, highly impact-resistant, often used for sports or extreme activities, providing the best eye protection. - Lens color
Sunglass lenses come in various colors, each with different advantages and disadvantages:- Black is most suitable for outdoor activities.
- Gray filters and reduces glare without distorting colors, ideal for beach trips.
- Orange or yellow enhances depth perception but distorts colors, not suitable for driving.
- Brown sharpens natural colors and light, improving vision especially for driving cars or motorcycles.
- Green filters and reduces glare well like gray, providing comfort especially for outdoor activities.
- Tea and dark gray are suitable for general use.
- Choose frames that suit your face shape
For square faces, curved or round frames are recommended. For round faces, large frames that cover the cheekbones and angular frames make the face appear smaller. For long faces, oval frames that cover the eyes completely are suitable, and oval faces can wear any style. - Try them on before buying
Wear the sunglasses and walk around, look up and down to ensure they don’t slip, and check if the lenses fit well in the frame or if the arms are bent. This helps you choose quality sunglasses that fit your face size properly.
However, if you buy sunglasses made from substandard materials, they may not filter UV light. In cases where the lenses are coated with color, these colors can make the eyes feel like they are in the dark. Normally, in the dark, pupils dilate. If you wear fake or poor-quality lenses, dilated pupils allow more UV light to enter the eyes, causing more damage and increasing the risk of eye diseases. It is easy to notice after wearing such sunglasses, as side effects from light entering the eyes may cause fatigue, eye pain, redness, tearing, and burning sensations.
Finally, not only should we wear sunglasses to protect our eyes, but we should also avoid places with high UV intensity, such as staying outdoors for long periods. If avoidance is not possible, wear sunglasses, wide-brimmed hats, or use umbrellas to help protect your eyes for lifelong good health.
