Real Time Image Processing during Observation of Magnetic Domain Structures by Kerr Microscopy

Abstract

Subject classification: 75.60.Ch; S1.2 A computer program has been created which acquisits images from a Kerr microscope and performs data processing. It interacts with an 8-bit CCIR camera, a digital 16-bit camera, two monitors and a power supply for external magnetic fields. The program performs real time processing such as: false colour palette, dynamic false palette, histogram calculation, differential and normalized differential imaging. Time critical procedures are optimised for architectural features of the Pentium 1 II and multimedia extension instruction set (MMX). The program operation during the observation of magnetic domains created in a thin Co film, in the configuration of longitudinal Kerr effect, has been demonstrated.Introduction The domain structure images observed by Kerr microscopy contain nonmagnetic contributions which make the interpretation difficult. Because some of them can be eliminated by digital image processing, the real time domain structure observation is preferred. For this purpose an embedded device (ARGUS-20, Hamamatsu Corporation) or a properly equipped personal computer (PC) can be used. In this paper software and hardware based on a PC are demonstrated which are cheaper and more flexible than a conventional image processing machine.

Observation of the domain structure in Fe–Au superlattices with perpendicular anisotropy

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Magnetization reversal and field annealing effects in perpendicular exchange-biased Co∕Pt multilayers and spin valves with perpendicular magnetization

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