Eyeglasses, prescription eyeglasses, sun glasses, and other vision correction glasses

Eyeglasses and prescription eyeglasses made of plastic lenses or glass lenses

Prescription eyeglasses, prescription glasses, corrective lenses, spectacles, specs or prisms are worn in front of the eyes to correct defects of vision (refractive error) or to protect the eyes. The most common form of eyeglasses consists of a pair of glass lenses in a metal or plastic frame fitted to the bridge of the nose. The frame is held in place by bows, or arms, that grip the head or hook around the ears. Lenses made of hard plastic are often worn for their increased safety and light weight.

Eyeglasses lenses for farsightedness and nearsightedness

The lenses of eye glasses are ground with different curvatures to correct various vision defects. Prescription glasses are primarily designed to correct for refractive error in the eye such as reading glasses for accomodative loss (presbyopia) nearsightedness (myopia), farsightedness (hyperopia) and astigmatism. Reading glasses are often used for some cases of farsightedness.

Eyeglasses lenses – from bifocal glasses to multifocal to varilux

Several different lens shapes may be used and combined in a single set of eyeglasses to make bifocals, trifocals, multifocals, or progressive addition lenses (PALs or varilux) or adds with spheric, aspheric convex, biconvex, concave, biconcave, cylinder and prism. Special high index materials allow pseudophakic eyeglass prescriptions to be lightweight. It is now possible to find many sources of eye glasses online, including designer eyeglasses, discount eye glasses, reading glasses, and many different types of sunglasses. The first step towards obtaining eyeglasses is to have a vision exam and eye exam from your opthalmologist or optometrist. Your eye doctor will assess whether you are nearsighted, farsighted, have astigmatism, and determine your lens prescription.

Sun glasses and other eyeglasses such as safety glasses

Eyeglasses are also worn to protect the eyes from the ultraviolet (UV protection) rays of the sun (sunglasses or sun glasses) with tinted lenses, photogray, photochromatic, antireflective coating (AR), polarized or tint coatings. Other special form of safety eyewear protect the eyes from welding flames and from flying particles of metal (safety goggles or safety glasses), or from the wind (aviator's or driver's goggles).