Abstract: An oscillating laser welding with filler wires for jointing aluminum alloy sheets with a large gap therebetween, including the following steps: providing two aluminum alloy sheets first, and reserving a gap (2) and keeping the gap with a constant width between opposite surfaces of the two aluminum alloy sheets to be jointed; providing a laser welding head (1), a wire feeding nozzle (3), and a protective gas nozzle (4) above the gap; presetting a welding start guiding plate (5) at a welding starting end of the gap, forming a molten pool on the welding start guiding plate by a laser beam, and guiding the molten pool to the welding starting end of the gap; and enabling the wire feeding nozzle and the laser welding head to correspond to the gap and travel in the same direction. The aluminum alloy welding wires fill the whole gap after being heated and molten by the laser beam, and the welding of the two aluminum alloy sheets is completed.

Abstract: A laser anti-reflection device includes a polarizing beam splitter, a ?/4 wave plate and an absorber disposed in an outgoing light path of a laser emitting linearly polarized light with a wavelength of ?. The linearly polarized light from the laser passes through the polarizing beam splitter and the ?/4 wave plate in turn to become a circularly polarized light beam. Part of the circularly polarized light beam is then reflected by a workpiece to be processed along the original light path and passes the ?/4 wave plate to become a linearly polarized light beam with a polarization direction vertical to that of the outgoing linearly polarized light beam. The vertical polarized beam passes the polarizing beam splitter, deviates from the light path of the outgoing linearly polarized light beam and reaches the absorber. The laser anti-reflection device prevents reflected light from damaging the laser from high power lasers.

Abstract: A laser anti-reflection device includes a polarizing beam splitter, a ?/4 wave plate and an absorber disposed in an outgoing light path of a laser emitting linearly polarized light with a wavelength of ?. The linearly polarized light from the laser passes through the polarizing beam splitter and the ?/4 wave plate in turn to become a circularly polarized light beam. Part of the circularly polarized light beam is then reflected by a workpiece to be processed along the original light path and passes the ?/4 wave plate to become a linearly polarized light beam with a polarization direction vertical to that of the outgoing linearly polarized light beam. The vertical polarized beam passes the polarizing beam splitter, deviates from the light path of the outgoing linearly polarized light beam and reaches the absorber. The laser anti-reflection device prevents reflected light from damaging the laser from high power lasers.