Lasers welders produce a beam of high intensity light which, when focused into a single spot, provide a concentrated heat source, allowing narrow deep welds and fast welding speeds. The process is frequently used in high volume applications such as in the automotive and medical industries. Laser welding is a non-contact process which requires access to the weld zone from only one side of the parts being welded. There are many joint geometries that can be welded, but there must be a close fit-up at the joint interfaces, which makes tooling a key aspect for laser welding success.

Three types of welds can be achieved with a laser welder: conduction, transition/keyhole and penetration or full keyhole. Conduction welds are performed at low power, resulting in wide, shallow weld nuggets. Transition/keyhole welds utilize medium power density and result in a deeper weld nugget typically with a width to depth ratio of around 1. Penetration or full keyhole welds are resultant of direct power delivery into the material via the keyhole resulting in deep, narrow welds with width to depth ration typically between 3-10.