To put it simply, laser cutting works by a high intensity beam generated by a laser source being directed on a work piece with the help of mirrors placed at distinct positions. This beam is then concentrated with the help of lens on the small spot on the work piece that is to be cut. The intense laser beam immediately heats up and melts the work piece. At this stage, an assist gas is also applied to cool and protect the focusing lens.

Starting with a small hole, a high intensity beam creates a cut either by moving the work piece while the beam is kept still, or by moving the beam across the work piece being cut. Sometimes both these methods are used. An intense light beam strikes the part of the material or object, causing it to burn, melt and evaporate without any trace of heat.

Not all materials need the same amount of power. Thinner materials need lesser power and thicker ones need more laser power. Usually, CO2 (carbon dioxide) laser cutting UK is done at 1000-1500 watts. Materials such as steel may need more than three kW.