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.
There are several types of eyeglasses. Examples are extreme magnification, progressive, trifocal, bifocal, reading, 3D, sun, safety, and corrective glasses. Corrective glasses have lenses that adjust focal lengths to improve astigmatism, farsightedness, and nearsightedness.
Nearsightedness is when objects look blurry that are far away but close objects are clear. Glasses lenses worn by people with this condition are concave in shape. Farsightedness is corrected by using convex lenses that help objects that are close appear less blurry. Cylindrical shaped lenses are used to improve astigmatism, which otherwise impairs the pathway of light to the retina. Corrective forms of eyeglasses improve individuals sight and minimize side effects, such as headaches.
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 give the illusion of three dimension when looking at a two dimensional surface. This is done by having one red lens and one blue one. Or another option is to have one polarized vertically and the other polarized horizontally. The key is to have each eye take in different information.
Eyeglasses come in all shapes, sizes, and uses. They are worn for sight correction and vision protection, and sometimes only to make a fashion statement. Even 3D versions are available and used to see in three dimensions for the sake of entertainment.
There are many different types of eyeglasses available to satisfy your every need. The premier 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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