MAGNETIZING STATE EVALUATING METHOD FOR MAGNETIC RECORDING MEDIUM

摘要

PROBLEM TO BE SOLVED: To highly accurately detect the cluster size of a magnetic recording medium by preparing a gradation image by converting magnetization strength at each measuring point the density value of a pixel, and calculating an area composed of pixels having the similar density values with a genetic algorithm. SOLUTION: The magnetization strength at each measuring point is measured by scanning a signal recording part on the magnetic recording medium to evaluate a magnetizing state with the probe of a magnetic force microscope, and the gradation image is prepared by converting that magnetization strength at each measuring point to the density value of the pixel. The area composed of pixels having the similar density values on that gradation image is calculated by the genetic algorithm and a specified density area is extracted from the gradation image. That specified density area is displayed in prescribed shape such as ellipse, for example, the cluster size of the magnetic recording medium is discriminated from the area of that prescribed shape and the magnetizing state of the magnetic recording medium is evaluated from that cluster size. Thus, magnetic characteristics can be exactly evaluated.