While the ray model is outdated as a physical theory, it is still an extremely valuable conceptual and computational tool for the design and modeling of optical systems. It is therefore important to know the limits of its validity as well as its connection to the more physical wave framework.
Its importance is partly due to the fact that it corresponds to a limiting case of the wave theory in several situations, including those of short wavelength (in many different ways) and statistical incoherence. Accurate wave field estimations can result from the ray model if a suitable framework is employed. In this talk, an overview is given of the many ways in which the ray and wave models can be related. Some of these approaches rely on "dressing" rays with wave contributions, while others make use of what is known as Wigner functions, which are mathematical representations also used in signal analysis and quantum physics. The mathematical analogy between the ray-wave and the classical-quantum connections will also be discussed.