US Patent 7605342 Laser processing head

A laser processing head includes a first housing region associated with a beam guidance of a laser processing machine, a second housing region associated with the laser processing head, and an aperture in a wall separating the first and second housing regions. The head is configured such that a laser beam may pass sequentially through the beam guidance, the first housing region, the aperture, and the second housing, and the first housing region includes a first gas atmosphere associated with the beam guidance and maintained at a higher pressure than a second gas atmosphere in the second housing region.