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People`s life style and occupation was restricted by sight before glasses had been invented. For example, hunter must have but handicraftsman who use myopia power usually have to retired after age of 45-50 because of their short sight. The early lens is plane-concave lens. It`s called [lens" because it looks like plane-concave. The early magnifying glass can be traced back to 10th century. And the increase of demand for well sight along with spread of atomization and invention of printing promoting the development of glasses In 13th century, people began to use the lens of glass to remedy sight, The melted glass was poured into a special mold to make into glasses. The first record of eye sight correcting is done by Roger Bacon. [The letters become bigger and clearer when you look through a crystal ball", written by him. Since Johan Gutenberg invented typewriter, with the rapid development of print, the demand of sight-remedy reached a new top. And mainly are convex lens for remedying presbyopia at that time. The concave lens is found soon to help myopia patient to see the objects in further distance. From that time people started to classify the lens by diopter but not age. The first glasses was two lens tied by a cord in front of eyes. In 18th century, Chinese invited the [ErCheng" Britain optometrist Edward Scanlett made primary glasses frame,became the embryo of update glasses.in 1784, Benjamin Franklin made the first pair of bifocal lens by two sets of lens. In 19th century, that`s the important period for the development of lens and glasses. In 1827s, Fuller invited cylindrical lens for remedy astigmatism. In 1860s, Snellen invited standard eye chart. In 1837s, Lsaac Schnaitman perfected demo bifocal lens. In 1899s, John Borisch invited amalgamation bifocal lens, and named it[contact bifocal". Today, all lenses have a standard base. It is appeared in 1890s. The producers of lens never stop to update their products to meet the request of the demand. They volume- produce of tint glasses (for example: sunglass) start from earlier 20th century, this kind of lenses is to perfect sight and reduce the harm of infrared ray.