Originally, lenses were made of transparent quartz and beryl, but increased demand led to the adoption of optical glass, for which Venice and Nürnberg were the chief centres of production. A concave lens for myopia, or nearsightedness, is first evident in the portrait of Pope Leo X painted by Raphael in 1517.
The earliest glasses had convex lenses to aid farsightedness. Jerome became the patron saint of the spectacle-makers’ guild. Jerome at a desk from which dangled eyeglasses as a result, St. The first portrait to show eyeglasses is that of Hugh of Provence by Tommaso da Modena, painted in 1352. In Europe eyeglasses first appeared in Italy, their introduction being attributed to Alessandro di Spina of Florence. In 1268 Roger Bacon made the earliest recorded comment on the use of lenses for optical purposes, but magnifying lenses inserted in frames were used for reading both in Europe and China at this time, and it is a matter of controversy whether the West learned from the East or vice versa.
#SPECTACLE LENSES HOW TO#
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