"Convex aspherical optical surface testing, has inherently several difficulties. They are considered as the most challenging to perform. Recent failures in achieving high performance telescopes like the Hubble Space telescope, have made a deep concern about the difficulties and importance of the tests. The importance in testing aspherical optical testing is evident from the constantly increasing papers in specialized journals around this subject. This document is built around three main subjects in three chapters. Chapter 1: Convex Surface Testing; Chapter 2: Projection of the Pupil in Non-Null Tests and Chapter 3: Digitization of Interferograms of Aspheric Wavefronts."