Sunglasses are the special type of eyeglasses in which lens is colored or darken in order to prevent strong light reaching to eyes. Sunglasses also known as tinted glasses. The popular firms for manufactures of sunglasses are Ray-Ban, Dior, Armani etc. The sunglasses can be used as safely lens and they are also a fashion symbol. Sunglasses are the symbol for many celebrities.
Many people like to spend hour in beach or snow. They like the activities like sunbath and reading in the sunshine. But sometimes sunshine is very bright and uncomfortable for eyes. Wearing sunglasses in the sunlight saves eyes from temporary loss of vision and prevents ultraviolet rays to reach eyes. Excessive exposure to ultraviolet light(in short UV light) can cause many short-term and long term eye-problems like photokeratitis, snow blindness, cataracts and many other diseases. You can find the
Sportsperson also like to wear Sunglasses. In outdoor games they are normally need to play in sunshine where sunglasses are very necessary. Sunglasses also save the sportsperson eyes from injuries, small dust particles and small mosquitoes which keep flying in atmosphere.
There is a category of sunglasses known as water-sunglasses which are made according to needs of swimmers and sea-divers. These glasses are shatter proof & impact resistent lenses.
Sunglasses are made of flexible frame and durable lens materials. Normally Crown glasses generally not used as lens material for sunglasses. Most popular lenses for sunglasses are CR39 plastic lenses and Polycarbonate lenses. Both are very light as compared to glass. CR39 is almost opaque to UV Rays and can be easilty dyed to various colors. Polycarbonate lenses are quality lensess, are light weight and have very high refractive index. Polycarbonate lenses are expensive but have many features.
Sunglasses frame are made up of nylon, and metals, For sports wear sunglasses frame should be flexible and light in weight.
Sunglasses are fashion symbols too. People specially young boys and girl like to wear sunglasses. Many celebriteis wore the sunglasses. There are many different brands of sunglasses available. Famous of which are Aviator, Mirrorshades, Onassis glassess etc. Aviators are sunglasses with an oversized teardrop-shaped lens and thin metal frames.
Mirrorshades are sunglasses with a mirrored coating on the surface
