Why Is It Dangerous to Look Directly at the Sun?

Sun emits light in three different forms: visible light, infrared rays, and ultraviolet rays (UV). Among these, the most harmful are the ultraviolet rays. This is because ultraviolet rays can cause serious damage not only to our skin but also to our eyes.

^{Sunrise (Photo: Mehmet Bağcı)}

Ultraviolet rays cause darkening of the skin and lead to sunburns. When the sun is viewed with the naked eye, a similar effect begins in the eye. The cells of the transparent layer covering the outer part of the eye swell and begin to crack upon exposure to ultraviolet rays.

The following symptoms occur in the eye damaged by ultraviolet rays:

• Tearing
• Burning sensation
• Feeling of grit in the eye
• These symptoms typically appear several hours after exposure to the sun and may disappear within a few days.

If exposure to ultraviolet rays continues for longer periods, the retina—the light- and color-sensitive layer inside the eye—begins to sustain damage. This condition can lead to permanent vision loss and even blindness.

^{Close-up of the Sun (with Solar Filter) (}Pixabay⁾

Looking directly at the Sun with the naked eye, or even with ordinary sunglasses, is extremely dangerous. To protect eye health, only specialized, certified solar filters must be used. In particular during events such as solar eclipses, viewing the Sun without proper protective eyewear is strongly discouraged.

An ideal sunglass lens protects eye health by blocking ultraviolet (UV) rays to an appropriate degree. UV rays can cause serious damage when they come into direct contact with the eye. In addition, high-quality lenses reduce the intensity of light reaching the eye, providing clearer and more comfortable vision. Individuals with blue or green eyes are particularly sensitive to light. This is because these eye colors contain insufficient pigments that help mitigate the harmful effects of light. As a result, these individuals are more exposed to the adverse effects of sunlight.

A critical criterion for sunglasses is that their lenses block more than 80% of harmful UV rays. Furthermore, lenses that also absorb infrared (IR) rays provide additional protection by preventing heat buildup between the lens and the eye. This reduces thermal stress around the eye area.

The sunglasses must provide protection not only against direct UV rays but also against rays coming from above, the sides, and reflected surfaces. Therefore, small lenses that sit far from the face and are designed purely for aesthetic purposes offer inadequate protection. Colored lenses without proper UV protection can cause the pupil to dilate, allowing more harmful rays to reach the retina.

In conclusion, when selecting sunglasses, it is essential to pay attention to the lenses’ UV and IR protection properties, as well as ensure the frame is designed to fit the face properly and block environmental light from all angles. This is of great importance for maintaining eye health.