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Sunglasses can offer protections against dangerous ultraviolet rays that come from the sunlight. If you are outside all the time, you must wear prescription sunglasses to protect your eyes. Without sunglasses, the ultraviolet ray can shine directly into your eyes and damage the cornea. The cornea can get burned when exposed to the ultraviolet ray for a long period of time. Later, the vision of your eyes will become blurred. In the end, the victim will suffer from blindness. Besides, the skin around your eyes will be exposed to the ultraviolet ray. Ultraviolet ray can cause the skin to develop cancer. Cancer is a kind of disease that can spread to other parts of the body and cause death to the person.
When you are driving a car during a hot day, you have to wear sunglasses. When an intense light shines into your eyes, you will automatically close them. When the eyes are closed, you will not be able to see what is ahead clearly. Your retina will suffer from damage when too many rays try to enter the eyes. Sunglasses are able to block about 97% of ultraviolet rays. Some sunglasses can block 100% of ultraviolet rays. When shopping for sunglasses, make sure you check the percentage of ultraviolet ray protection in the label. If there is no statement about the level of protection, it means the sunglasses won’t offer protection against ultraviolet ray.
There are two types of prescription sunglasses including polarized and photochromatic sunglasses. Polarized sunglasses are able to refract away horizontal light. A light that travels at a horizontal line is known as polarized light. Polarized light can be refracted from a flat surface such as lake, sea, river and etc. It can refract itself from a highway to the lens. When it is refracted from the highway, it can block your vision and prevent you from seeing properly. The glare will cause your eyes to feel pain and have tears. As a result, you won’t be able to see clearly.
Photochromatic sunglasses have different functions than the polarized sunglasses. When you are outside, the photochromatic sunglasses will automatically become dark because of the light. The ultraviolet ray from the sunlight causes the photochromatic sunglasses to darken. When you are in a dim place, it will return to the original state. |
