The UN designated International Year of Light and Light-based Technologies (IYL2015) provided a worldwide stimulus to optical sciences and associated technologies. The year-long celebrations of light were a good occasion to revisit the history of optics. The year 2015 had the millennium anniversary of the encyclopaedic seven volumes on optics by the legendary Arab scholar Ibn al-Haytham. Recent analysis by the mathematician and science historian Roshdi Rashed demonstrates that the law of refraction of light had been penned down in detail by Ibn Sahl, who was the teacher of Ibn al-Haytham. In the absence of this major historical discovery, we would have continued to attribute the law to the European Renaissance scientists. Here, we describe the Mediaeval Arab achievements in optics and its influence on the European sciences. Looking ahead, we also briefly examine the ways in which the light sciences can provide a platform for international science collaborations and revival of science in the Arab lands.