ENHANCEMENT OF MAGNETO-OPTICAL DOMAIN OBSERVATION BY DIGITAL IMAGE-PROCESSING

An electronic system is described which makes it possible to subtract contrast of nonmagnetic origin from a magneto-optic image. At the same time image noise can be reduced to such a degree that the contrast visibility limit in domain observation is expanded by at least an order of magnitude. The system is demonstrated for a number of applications in which domain analysis was not possible before. These include magnetostriction-free metallic glasses, nonoriented silicon-iron steel, and polycrystalline Ni-Fe samples. For the first time the internal wall structure could be made visible on metallic samples by magnetooptical means.