The experiment P5.1.1.2 deals with the change of direction when light passes from one medium into another. The law of refraction discovered by W. Snell is quantitatively verified:

This experiment topic also studies total reflection at the transition from a medium with a greater refractive index to one with a lesser refractive index, the concentration of a parallel light beam at the focal point of a collecting lens, the existence of a virtual focal point when a parallel light beam passes through a dispersing lens, the creation of real and virtual images when imaging with lenses and the ray path through a prism.