| 摘要 |
PURPOSE:To improve the iron loss value of a directional magnetic steel sheet by condensing laser light by the use of a plurality of condensing units constituted by beam splitters and condensing lenses and irradiating said light to the surface of the magnetic steel sheet in the direction normal to the rolling direction of the steel pate. CONSTITUTION:An n number of condensing units 6 constituted by beam splitters 3 and condensing lenses 4 are installed above an magnetic steel sheet 1 in the width direction normal to the rolling direction of the steel plate. If the plate width is defined as W, the space between the condensing units becomes W/n. The laser light emitted from a loaser oscillator 2 is passed through and reflected by beam splitters 3-3'' and is finally reflected by the total reflecting mirror 5, thence it is condensed by the condensing lens 4, so that the laser light is condensed onto the magnetic steel sheet 1. This condensing point is moved by a distance W/n in the width direction of the magnetic steel sheet to irradiate the entire surface. In this case, it is equally well to form slender laser light focuses 8 by using semicylindrical lenses 7 in place of the condensing lenses. |
