Windscreens are in every car, and a standard position of modern ADAS cameras is behind the glass. The optical quality of the windscreen thus influences the image quality of the camera system, and hence the performance of the computer vision algorithms. As these algorithms are often based on Machine Learning it is hard to link the performance of these algorithms to the optical quality of the windscreen. There is an established and standardized measurement „refractive power“ that quantifies the optical quality, which is used on every windscreen in the world. In a recent development the Modulation Transfer Function — MTF, know from camera ’sharpness’ characterization — is being explored as an alternative to refractive power. In this session we look at the usability of refractive power and MTF, and we explore novel ways to characterize windscreen quality. We take a fundamental look how to optically model the windscreen, such that it can be used in numerical simulations. A panel discussion closes this session.