Lentes Durante El Siglo 16

After supplies were in Europe and Russia , rock (quartz , beryl, or pebbles ) crystal , which is mined in Brazil and Argentina , was used because this hard material was more durable than ordinary glass . All were positive first lens or convex spherical .. During the 17th century colored lenses became popular. Mark went through a similar evolution and evaluation . The early frames were made of wood, horn, or bone. The first round lens frames were followed by oval , rectangular and eventually became popular in the mid- 1830s. Some subsequent frame materials include brass , hawksbill turtle shell , beards , steel, silver and gold. The show case of world's oldest existing was found in 1982 in Freiburg , Germany and probably dates from the 14th century .

As noted in the ages 15 and 16 , were riveted type was usually hand. These shows were developed in a more comfortable type arched bridge arc known as specifications . After this, the ultra - rare performances were slotted bridge cleavage to give some elasticity added to the bridge of the nose. Then a piece of wire ( usually copper ) frames with round lenses , better known as the Nuremberg style nose glasses , it became fashionable , to be mass produced throughout the 17th century and early 19th century . Compounding the problem of stability , The first shows no side arms . This serious problem was solved for about 440 years until finally London optician Edward Scarlett ( 1677-1743 ) was credited with perfecting the temple glasses

. Some thirty years later , the longer sides (temples ) in the middle hinge became popular. The latter change increased comfort and stability they need . Another London and optical instrument maker , James Ayscough , gets credit for the invention of the first double-hinged temple in 1752. These sides described as "so artificial as to press either the nose or the temples . " In 1783 , Addison Smith Optometrist obtained the first patent show, # 1359, in London for two additional lenses hinged above the distance correction and can turn down to close the work ( making a total of four lenses ) . In 1797 , English Optical John Richardson conceived the idea of four different lenses glasses where the two lenses supplementary patent # 2187, you could turn on when you work. That same year , English Optical Dudley Adams patented a device with a headband almost complete and foldable lenses and adjustable down . No part of the shows are based on the nose and the distance between the two lenses could be modified depending on the interpupillary distance.

Optical London Benjamin Martin (1704-1782) developed these glasses Visual in 1756 in an attempt to reduce the alleged injury to the eyes from excessive light . The aperture of the lens was reduced horn ring placed inside the regular -size frame . They are described in his "Essay on Visual Glasses ( commonly called Glasses) " and then continued to be popular during the Revolutionary

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