Optical communications—A decade of preparations

This paper, an introduction to this first Special Issue on Optical Communications, follows some of the arguments that have prevailed for and against optics as a viable communications medium for terrestrial and space applications, and assesses the present state of the art of optics devices, systems, and theory, based on discussions with scientists and engineers who have been specializing in the optical field. It also attempts in a small way to give some appreciation of the special problems the traditional communications engineer faces in readjusting his thinking and his "physical intuition" in going from the world of electrons to the world of photons.