Apart from the actual laser light source, many auxiliary systems are needed to safely operate a laser.
Safety system
Because laser radiation is hazardous, great care needs to be taken in handling it to ensure that both operators and bystanders are safe. First of all, a secure and separate working area is needed. No entrance should be allowed to the cell while the laser is in operation and the area around it should be shielded from direct or scattered radiation. The area should furthermore be equipped with safety features such as emergency stops, key control, etc.
(N.B. All lasers used for materials processes are Class IV. Extensive engineering and procedural controls are required to reduce the risk of exposure to the beam. Details are contained in EN 60825 (IEC 60825) Safety of Laser Products)
Beam transportation
This is defined as the means to transport the beam from the laser to the workpiece and depends on the type of laser. The wavelength of Nd:YAG laser light (1.06µm) allows it to be transported through an optical fibre, whereas laser light from a CO2 laser (wavelength 10.6µm) needs to be guided via mirrors. In the case of a CO2 laser, the position of the cell will require some thought in terms of its position relative to the source as increasing the number of mirrors in the beam line decreases the laser's intensity at the work piece.
Focusing optics
To get the unfocused beam produced by the laser bundled in as small as possible a spot size on the workpiece, focusing optics are needed. These can either be reflective (parabolic mirrors) or transmissive (lenses), although Nd:YAG lasers almost exclusively use lenses for focussing the beam.
Cooling system
Lasers, as a result of their low efficiency, need sizeable cooling systems in order to operate. Possible considerations with respect to the cooling system are the choice between gas and water cooling, and disposal or re-use of the heated medium. This choice will be based upon a number of factors such as cost, available space etc.
Beam and workpiece manipulation
In lasers materials processing, the spot, the workpiece, or both can be moved with respect to each other. To do this, there are many systems available ranging from relatively simple XY-tables to multi-axis robots. The choice of system depends on a number of factors such as the type of laser source, the complexity and size of the workpiece, etc.
Ancillary equipment
For many applications, ancillary equipment may be needed such as wire feeders, seam trackers, weld monitors, etc.
Fume
Fume extraction may be needed. This will depend on the nature of the materials being processed, and the need for extraction should be assessed before work commences.