Abū‘ Alī al- Ḥasan ibn al- Haytham( Alhazen)
of Basra( 10th- 11th century), mathematician and physicist; made significant contributions to the theory of optics, including refraction, reflection, binocular vision, and atmospheric refraction; first to explain correctly vision as the effect of light coming from an object to the eye.
In David C. Lindberg's(a recently deceased American science historian) chronological book“Theories of Vision: From Al-Kindi to Kepler”,
the author gives Ibn Al Haytham's definition of the theory of vision:
“Light illuminates all visible objects and this light later reaches the eye surface, allowing humans to perceive the object in question.”.