Abstract: A laser processing device 0 includes a combiner unit 3 configured to superimpose a plurality of laser beams L1 and L2 having different wavelengths on the same optical axis; a focus shifter unit 4 configured to adjust a focal length of the laser beams L1 and L2 superimposed by the combiner unit 3; and a Galvano scanner unit 5 located downstream of the focus shifter unit 4 and configured to change a direction of the optical axis of the laser beams L1 and L2 traveling toward a processing object, and the adjustment in the focal length performed by the focus shifter unit 4 is synchronized with the change in the direction of the optical axis performed by the Galvano scanner unit 5.

Abstract: A method for measuring the strength of a cavity surface (2a) of a mold (2) and for simultaneously pressing one or more marks (21a, 21b) in the cavity surface (2a) is disclosed. Such marks (21a, 21b) formed in a cavity surface of a mold are transferred to a cast when it is produced from the mold, and the transferred marks appearing on the surface of the cast display some information. The method includes the steps of pressing one or more marks (21a, 21b) in a cavity surface of a mold by using a press member (14) that has a pressure sensor (15), and measuring the strength of the mold (2) by detecting a reaction force by the pressure sensor (15) that acts on the press member (14) when the press member presses the mark in the cavity surface of the mold.