Eyeglasses are a combination of frames and lenses and rest in front of the eyes for vision correction and protection. Safety glasses can protect against light, radiation, or flying objects. Vision is improved in brightly lit situations by wearing sunglasses, which also reduce damage from ultraviolet light. Other types of glasses help with viewing visual information, are simply aesthetic, or are used for entertainment.
Glasses are constructed with padded supports that rest on the bridge of the nose and sides to rest on the ears. Most commonly used lenses are the CR-39 variety. These work well because they have low dispersion, are very lightweight, block radiation from ultraviolet and infrared light, and are scratch resistant.
Many varieties of eyeglasses exist. These include safety, extreme magnification, corrective, progressive, sun, trifocal, 3D, bifocal, and reading glasses. Corrective glasses can modify focal lengths to correct farsightedness, nearsightedness, and astigmatism.
Nearsightedness makes objects far away appear blurry and those close up seem clear. To improve this, lenses worn are concave in shape. Farsightedness is treated with convex shaped lenses and make objects close up less blurry. Cylindrical lenses fix sight issues from astigmatism, a disorder altering the path of light to the retina. All of these corrective eyeglasses successfully improve the sight of people with these problems. They also reduce the side effects they experience as a consequence of their conditions, such as headaches from squinting.
Safety glasses are given a plastic type lens that is shatter resistant. This helps it prevent damage to eyes from flying debris. These products vary greatly in the amount of protection they offer. Those worn in the medical field are customized especially for protection against fluid splattering. Those used in factories must shield eyes from metal, flying wood, and sawdust. Therefore, the glasses worn in factories must have a stronger type of lens and more shielding components. Lenses for either kind can be made into corrective versions.
Sunglasses can have prescription or darkened lenses. Darkened versions give added protection from light, including UV light. Photochromatic lenses can also be used, and these darken when they are exposed to UV rays. Light polarization is a modification that helps eliminate glare. This is ideal for pilots, who could otherwise be blinded by light during flight.
Yellow shaded lenses help increase color contrast and enhance depth perception. These are great for sight at dusk but possibly harmful if worn at night. Sometimes these are not worn for protection but for aesthetic reasons. Opaque glasses are also worn by blind individuals to conceal their eyes.
3D glasses make two dimensional surfaces appear three dimensional. This effect is created by having one lens blue colored and the other red. A variation of this is to have a lens polarized vertically and a lens polarized horizontally. The goal is to have each of the eyes receive different information.
Eyeglasses are highly versatile and come in different sizes, shapes, and uses. They can be worn to correct sight or protect vision, or sometimes only as a fashion statement. 3D versions are also made and used to make two dimensional things appear three dimensional, a means of entertainment.
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There are many different types of eyeglasses available to satisfy your every need. The premiere online retailer offers eyeglass frames for men, as well as a variety of eyeglass frames for women. Look your sharpest with these high-quality lenses.
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