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You may not have heard of Abu Ali al-Haytham. In the west he is known as Alhazen, a latinized form of his Arabic first name, al-Hasan. In all likelihood, though, you benefit from his lifework. He has been described as "one of the most important and influential figures in the history of science.
Facts
Alhazen has been called the "world's first true scientist."
He identified the basic principles underlying modern photography.
His work with lenses led to the development and production of early glasses, microscopes, and telescopes.