通过优化设备和工艺，可以通过提高小型化的效率和提高可操作性来提高处理效率。 一边调整钢板支撑辊的位置，一边支撑沿着生产线的钢板，并沿垂直方向控制钢板的位置的工序;激光照射工序，对钢板的表面照射激光，在钢板的表面形成槽; 包含，并且其中所述激光照射工序是在光学系统的钢板相对于所述钢板上旋转照射激光束包括在钢板的宽度方向相对于变换的激光束的辐射角在钢板的宽度方向的角度转换步骤 以及焦距保持步骤，根据激光束的焦距的变化来改变支撑钢板的钢板支撑辊的斜度。

By optimizing equipment and processing, magnetic domain refinement efficiency can be increased, workability can be improved, and processing ability can be increased through same. Provided is a method for magnetic domain refinement of an oriented electrical steel plate, the method comprising: a steel plate supporting roll position adjusting step of controlling the vertical direction position of a steel plate that progresses along a production line while supporting the steel plate; and a laser emitting step of emitting a laser beam onto the steel plate surface and melting the steel plate to form a groove in the surface of the steel plate, the laser emitting step including an angle changing step of rotating an optical system, which emits the laser beam onto the steel plate, with respect to the steel plate, and changing the emitted angle of the laser beam with respect to the width direction of the steel plate, wherein the method further comprises a focal distance maintaining step of changing the tilt of the steel plate supporting roll to support the steel plate to match the change in focal distance of the laser beam along the width direction of the steel plate.