An Arab mathematician, astronomer, and physicist of the Islamic Golden Age. Also referred to as "the father of modern optics", he made significant contributions to the principles of optics and visual perception in particular, his most influential work being his Kitāb al-Manāẓir, "Book of Optics", written during 1011–1021, which survived in the Latin edition. A polymath, he also wrote on philosophy, theology and medicine.