I. Introduction
Magneto-Optical indicators (MOIs) based on epitaxially grown iron garnet films provide the possibility to detect in real time two-dimensional magnetic patterns, such as magnetic flux in superconductors, magnetic tracks on audio and video tapes, security features on bank notes, and currents in microelectronic circuits [1] [2] [3]. In this sense, these garnet films can be used for nonscanning imaging of the fringing fields induced by two-dimensional magnetic patterns. Therefore, unlike scanning techniques, the MOI technology allows real-time imaging of dynamic processes such as domain wall motion and magnetization reversal.