Ibn al-Haytham Alhazen (965–1040 AD)
Ibn al-Haytham Alhazen made significant improvements in optics, physical science, and the scientific method.
In medieval Europe, he was honored as Ptolemaeus Secundus ("Ptolemy the Second") or simply called "The Physicist." He is also sometimes called al-Basri (Arabic: البصري) after Basra, his birthplace. He spent most of his life close to the court of the Caliphate in Cairo and earned his living authoring various treatises and tutoring members of the nobilities.
In his book, “Book of Optics,” he showed through experiment that light travels in straight lines, and carried out various experiments with lenses, mirrors, refraction, and reflection, which earned him the title of the "Father of Modern Optics."