LASER CUTTING METHOD FOR METAL FOIL

In a laser cutting method for metal foil, for example, a surface of a metal foil serving as a processing target is intermittently irradiated with a pulse of laser beam at a frequency of 1 [MHz] or less to cut the processing target by laser. For example, when the frequency is A [Hz] and a full width at half maximum of the pulse is B [s], the duty ratio Rd [%] expressed by Rd = A × B × 100 may be 0.1 or more and 80 or less. The pulse ratio Rp expressed as Rp = F/B may be 1 or more and 7 or less when the full width at half maximum is B and a 1/e width of the pulse is F [s], an M2 beam quality of the laser beam may be 1.2 or less, and energy applied by the pulse may be 0.1 [mJ] or more.