A laser welder was a tool used to join two or more parts. It produced a continuous welding beam and was normally used for welding metal together.

In 2369, a group of mercenaries boarded the USS Enterprise-D during preparations for a baryon sweep. The terrorist Devor attacked Captain Picard from behind with a laser welder, but Picard disabled him using a Vulcan nerve pinch. On another occasion, once the baryon sweep had begun, Picard ran across Devor once again; Picard asked Devore what he was doing on the starship and threatened him with the laser welder. (TNG: "Starship Mine")

Laser technology
Tools: autosuture • bone-knitting laser • laser beacon • laser drill • laser scalpel • laser scanner • laser torch • laser welder • microscope laser • miniature laser • nanopulse laser • tri-laser connector
Weapons: Artonian laser • cutting beam • laser cannon • laser detonator • laser pistol • pulse laser • x-ray laser
Other: laser fusion initiator • laser micrometer • LIDAR • optic nerve laser welding • laser pulse system