Abū ՙAlī al-Ḥasan ibn al-Ḥasan ibn al-Haytham, known in the West as Alhazen, was an Arab-Islamic scholar who helped develop the science of ophthalmology during the medieval era. He was the first to reject firmly the extramission theory of vision, which was prevalent during his time, and suggested that the eyes are the source of the light rays responsible for vision. Ibn al-Haytham in his book entitled Kitab al-Manazir (Book of Optics) explained vision based on light emanating from objects. In this study we review Ibn al-Haytham's life and introduce his major contribution to the field of ophthalmology, his theory of vision.
Keywords: Ibn al-Haytham; Kitab al-Manazir; eye; medieval history.
© IMechE 2014.