| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a laser beam machining method capable of cutting a machining object, without developing a crack or welding on the surface of the machining object, and efficiently. SOLUTION: Inside the machining object 1, a reforming area is formed by radiating a pulse laser beam L onto the predetermined line 5 for cutting, under the condition of causing multiple photon absorbtion, and making a condensing point P agree with the inside of the machining object 1. The pulse laser beam L is a linear polarized light, and its direction is controlled so as to be along the predetermined line 5 for cutting. By splitting the machining object 1 along the predetermined line 5 for cutting making the reforming area a starting point, the machining object 1 can be cut with a comparatively small force. Since in the irradiation of the laser beam L, the pulse laser beam L is scarcely absorbed on the surface 3 of the machining object 1, the surface 3 is not melted caused by the formation of the reforming area. Since in the reforming area, the size in the direction along the predetermined line 5 for cutting can be made relatively larger, the reforming area along the predetermined line 5 for cutting can be formed with a small shot number.</p> |
