At the launch of my novel The Reluctant King an actor friend of mine, Justin Aylmer, who was dressed in medieval costume and reading extracts from the book, apologised that he had to wear glasses because they would be somewhat incongruous with his costume. I was happy to inform him that, contrary to what many people might think, glasses or spectacles are not a modern invention.
The concept of magnification by using a lens is mentioned as far back as the 1st Century A.D. when Seneca the Younger mentions the magnifying effects of using a globe to read small text.
Much later, in his seven volume Book of Optics, Alhazan, born in Basra, Iraq in 965, investigated the magnifying power of the lens. Al Hazan was one of the great Arab experimentalists and a pioneer of optical science.
By the 13th Century spectacles were being manufactured in Italy. The invention of spectacles would have been an incredibly significant technological advance because it enabled scholars to continue their studies undimished by the natural deterioration of eyesight with age. Petrach, who was born in 1304 wrote: “I had … a vision that for many years was sharp. (But it failed me unexpectedly when I was over sixty, so that I was forced reluctantly to the use of spectacles.)”
We also have concrete evidence of these early spectacles in medieval paintings. It is interesting to note in these paintings that it is mainly monks and religious who wear spectacles. This is not surprising since reading and writing were almost exclusively within the competence of the church.