Reflection and refraction in Robert Grosseteste's De Lineis, Angulis et Figuris

TL;DR

This paper explores Grosseteste's medieval treatise on reflection and refraction, comparing his qualitative geometric rules and discussions on light's power with modern Fresnel reflectance theory.

Contribution

It provides a historical analysis linking Grosseteste's early ideas on light behavior with contemporary optical principles, highlighting the conceptual parallels.

Findings

Grosseteste's rules align with modern geometric optics.

His discussion on light's power prefigures aspects of Fresnel's theory.

Historical insights into medieval understanding of optics.

Abstract

In his scientific treatise entitled De Lineis, Angulis et Figuris, seu Fractionibus et Reflexionibus Radiorum, Robert Grosseteste is discussing some qualitative geometric rules about reflection and refraction. However, he is also discussing about the power of reflected and refracted light. The reading of these discussions is quite interesting, and what Grosseteste is telling seems well-posed, when compared with the Fresnel reflectance.