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Robert Grosseteste (ca. 1168–1253) writes De Iride , De Luce , De Colore , and other works on optics and light, lenses and mirrors, describing rectilinear light propagation as a wave phenomenon analogous to sound, and analyzing the optics of the rainbow in terms of refraction. Witelo (d. ca. 1281) writes Perspectiva around 1270, treating geometric optics, including reflection and refraction.
There are many ways to create a timeline in Excel, but most of the methods I have seen make use of the drawing tools or bar charts or a gantt chart for project timelines.