When were glasses invented?

Magnifying lenses had been used before, but wearable spectacles first appeared in Italy around 1286, probably in Pisa or the glassmaking centre of Venice. A friar, Giordano da Pisa, said in a sermon in 1306 that the art of making spectacles had been discovered less than 20 years earlier. The earliest known painting of someone wearing glasses dates from 1352. Early glasses had convex lenses for reading; concave lenses for short-sighted people came in the 15th century. Benjamin Franklin is credited with inventing bifocals in the 1780s.