Sunglasses
Sunglasses are a visual aid, variously termed spectacles or glasses, which feature lenses that are coloured or darkened to screen out strong light from the eyes. more...
Many people find direct sunlight too bright to be comfortable, especially when reading from paper on which the sun directly shines. In outdoor activities like skiing and flying, the eye can receive more light than usual. It has been recommended to wear these kind of glasses on sunny days to protect the eyes from ultraviolet radiation, which can lead to the development of a cataract. Sunglasses have also been associated with celebrities and film actors primarily due to the desire to mask identity, but in part due to the lighting involved in production being typically stronger than natural light and uncomfortable to the naked eye.
From the 1950s to the 1990s sunglasses were popular as a fashion statement, especially on the beach.
Uses
Hiding one's eyes has implications in face-to-face communication: It can hide weeping, being one of the signs of mourning, makes eye contact impossible which can be intimidating, as in the stereotype of the guardian of a chain gang, or can show detachment, which is considered cool in some circles. Many cultures do not take them kindly. Darkened sunglasses of particular shapes may be in vogue as a fashion accessory. Note that normal glasses are very rarely worn without a practical purpose. Curiously, they can project an image of uncool nerdiness that sunglasses do not have. The impact on nonverbal communication and the cool image can be the reasons for wearing sunglasses by night or indoors. People also wear sunglasses when they do not wish others to see that they are intoxicated from recreational drug use, this can be to hide dilated or contracted pupils or bloodshot eyes.
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