STEEL PLATE INSPECTION APPARATUS, STEEL PLATE INSPECTION METHOD, AND STEEL PLATE MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To improve manufacturing yield by performing visualized inspection of a magnetic domain structure of a steel plate immediately after its magnetic domain segmentalization processing.SOLUTION: A steel plate inspection apparatus 1 according to the present invention comprises: a magnetooptical element 5 converting a magnetic domain structure of a steel plate to be inspected into optical characteristics detectable as optical characteristics; a light source 7 irradiating the magnetooptical element 5 with linear polarization; a detector 12 for detecting the linear polarization whose polarization plane is rotated in accordance with the magnetic domain structure of the steel plate that has been transcribed to the magnetooptical element 5; and a drive mechanism for driving at least the magnetooptical element 5 so as to make the steel plate contact with and depart from the magnetooptical element 5.