Book of Optics - by Alhazen (Ibn al-Haytham)

Written between 1011 and 1021, this seven-volume Arabic treatise by the 11th-century polymath revolutionized optics. Alhazen’s experimental approach disproved ancient theories (like Euclid’s emission theory of vision), establishing that light travels in straight lines and vision occurs via light reflecting into the eyes. His work on lenses, perspective, and visual perception influenced Renaissance science and remains a cornerstone of optical theory.