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Glasses, spectacles, or eyeglasses are frames bearing lenses worn in front of the eyes, sometimes for purely aesthetic reasons but normally for vision correction or eye protection . Special glasses are used for viewing 3-D images or virtual reality.
Modern glasses are typically supported by pads on the bridge of the nose and by arms placed over the ears. Historical types include the pince nez, monocle, and lorgnette .
Glasses are more often called eyeglasses in North American English, spectacles in British English, and (rarely) frames or lenses. Spectacles is often shortened to specs. In hipster slang they are cheaters. Also see usage of words for eyepieces for a more detailed examination of the different usages for these words.
Glasses were originally made from glass, but many are now made from plastic due to the danger of breakage and the greater weight of glass lenses. Glass lenses, on the other hand, are much less susceptible to scratching.
Corrective spectacles have lenses shaped to correct some kinds of vision abnormalities.
Safety glasses are a kind of eye protection that protects against flying debris but may also protect against visible and near visible light or radiationRadiation generally means the transmission of objects or information from a source into a surrounding medium or destination. Within physics, related concepts are: Ionizing radiation is a stream of particles (photons or other particles) with sufficient ene.
SunglassesSunglasses (also called sun spectacles see usage of words for eyepieces) are a kind of visual correction aid, variously termed spectacles or glasses, which feature lenses that are coloured or darkened to screen out strong light from the eyes. Many people protect against high levels of visible and ultraviolet light.
Glasses were invented in northern ItalyThe Italian Republic or Italy ( Italian: Italia is a country in the south of Europe, consisting mainly of a boot-shaped peninsula together with two large islands in the Mediterranean Sea: Sicily and Sardinia. To the north, where it borders France, Switzer, most likely in the late 1280sCenturies: 12th century 13th century 14th century Decades: 1230s 1240s 1250s 1260s 1270s 1280s 1290s 1300s 1310s 1320s 1330s Years: 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 Events and Trends 1280s.. The identity of the orginal inventor is unknown. In 1676, Franciscus Redi, a professor of medicine at the University of Pisa, wrote that he possessed a 1289 manuscript whose author complains that he would be unable to read or write were it not for the recent invention of glasses, and a record of a sermon given in 1305, in which the speaker, a DominicanThe adjective Dominican can refer to several different topics. The Dominican Republic The island-nation of Dominica The Dominican Order. monk named Fra Giordano da Rivalto, remarked that glasses had been invented less than twenty years previously, and that he had met the inventor. Based on this evidence, Redi credited another Dominican monk, Fra Alessandro da Spina of Pisa, with the re-invention of glasses after their original inventor kept them a secret, a claim contained in da Spina's obituary record. In 1738, a FlorentineFlorence ( Italian, Firenze is a city in the center of Tuscany, in north-west Italy, on the Arno river, with a population of around 400,000, plus a suburban population in excess of 200,000. Florence is the capital of the region of Tuscany and briefly ( 18 historian named Domenico Manni reported that a tombstone in Florence credited one Salvino d'Armato (died 1317) with the invention of glasses. Other stories, possibly legendary, credit Roger Bacon with the invention. Bacon's published writings describe the magnifying glass (which he did not invent), but make no mention of glasses.
These early spectacles had convex lenses that could correct the farsightedness ( presbyopia) that commonly develops as a symptom of aging. The earliest definite evidence for the use of concave lenses to correct nearsightedness ( myopia) is Raphael's portrait of Pope Leo X, painted between 1517 and 1519. However, it was not until 1604 that Johannes Kepler published in his treatise on optics and astronomy, the first correct explanation as to why convex and concave lenses could correct presbyopia and myopia. The American scientist Benjamin Franklin, who suffered from both myopia and presbyopia, invented bifocals in 1784 to avoid having to regularly switch between two pairs of glasses. The first lenses for correcting astigmatism were constructed by the British astronomer George Airy in 1827.
Over time, the construction of spectacle frames also evolved. Early eyepieces were designed to be either held in place by hand or by exerting pressure on the nose (pince-nez). Girolamo Savonarola suggested that eyepieces could be held in place by a ribbon passed over the wearer's head, this in turn secured by the weight of a hat. The modern style of glasses, held by sidepieces passing over the ears, was developed in 1727 by the British optician Edward Scarlett . These designs were not immediately successful, however, and various styles with attached handles such as scissors glasses and lorgnettes remained fashionable throughout the 18th and into the early 19th century.
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