Why do mountain climbers have to wear black glasses?
Climbers who climb high mountains must wear black glasses, that’s why? It’s for eye protection. It turns out that in high mountains, the radiation of sunlight is especially strong. This is because the air in the high mountains is very thin. At an altitude of 8000 meters above sea level, the air density is only about one-third of sea level. Also, the air in the high mountains was hindered. On high mountains, mountain slopes, and mountain peaks from 4000 – 5000 m above sea level, most of them accumulate white snow after a thousand years without melting.
Further up is ice everywhere, immense silver sea. White objects have a very strong ability to reflect light. When nothing is covered, white snow reflects the sunlight very violently.
Sunlight and the visible light of all kinds of colors, from the Sun radiating to the Earth, also have a large amount of ultraviolet and infrared rays. In high mountains, solar radiation is particularly strong. Of course, ultraviolet and infrared rays also increase. The eyes are the most sensitive light-sensing organ of the human body. Strong ultraviolet and infrared rays shine on the visual retina of the eye and burn the retina’s visual retina, causing vision impairment; in severe cases, it even leads to blindness completely. Medicine calls this kind of phenomenon snow blind.
Therefore, for high climbers, to protect eyes, it is necessary to wear black glasses. The lenses of this dark type of glasses are not ordinary glasses but glasses that add iron oxide and cobalt oxide to absorb infrared and ultraviolet rays. The two chemicals mixed after being added to the glass, making it black. The dark glasses worn by mountain climbers are these specially made glasses.