Abstract: A coincident three axis manipulator comprises a first member which is mounted to rotate about a first axis and carries a second member which is mounted to rotate about a second axis obliquely inclined to the first axis. The second member carries a third member which is mounted to rotate about a third axis obliquely inclined to the second axis. First and second mirrors are carried by the first member and mounted to rotate with it. The first mirror is situated on the first axis and positioned to reflect a laser beam which is parallel to the first axis on to the second mirror which is on the second axis. Third and fourth mirrors are carried by the second member and mounted to rotate with it. The third mirror is situated on the second axis and positioned to reflect the laser beam reflected by the second mirror on to the fourth mirror. The fourth mirror is situated on the third axis positioned to direct the laser beam parallel to the third axis.

Abstract: Laser welding apparatus includes a first mirror whose angle may be adjusted but which is fixed in position and on which a laser beam is incident. The first mirror reflects the laser beam onto a second mirror which may be rotated through at least 180.degree. about the axis of the articles to be welded and which reflects the laser beam onto a third mirror whose angle may be adjusted and which may be rotated through at least 360.degree. about the axis of the articles to be welded. The laser beam then passes to a focussing mirror which focusses the beam through a welding nozzle onto the surfaces to be welded. In use, the third mirror is continuously rotated about the entire periphery of the articles to be welded and the positions and/or angles of all the mirrors are adjusted to ensure that the laser beam is transmitted along the desired pathway.