MAGNETIC RECORDING MEDIUM AND TRUTH DETERMINATION METHOD THEREFOR

摘要

A magnetic recording medium comprising a first confirmation portion having a magnetic data portion on the substrate and a desired degree of optical transmission, and a second confirmation portion constituted by a magnetic material separately from said magnetic data portion. To determine the truth of the magnetic recording medium, the light transmittance in the first confirmation portion is detected to determine the truth of the substrate and then the magnetic material in the second confirmation portion is detected to determine the kind thereof.