“Laser” covers several very different machines. The main difference is the wavelength — the colour of the light — because each material absorbs some colours and lets others pass straight through.
CO2 lasers
CO2 lasers produce invisible far-infrared light that wood, paper, leather and nearly all plastics absorb very well. That makes them the workhorse of craft and sign workshops: they cut acrylic of any colour, including clear, and handle wood and plywood with ease. Their light is guided by mirrors from a glass tube to the head. On their own they cannot cut bare metal.
Diode lasers
Diode lasers use a small semiconductor module, usually emitting visible blue-violet light. They are compact and affordable and engrave wood, leather and card very well, and can cut thinner wood. But blue light passes through clear acrylic and is barely absorbed by blue or transparent materials, so those are out of reach.
Fibre lasers
Fibre lasers work in the near-infrared, which metals absorb well. Smaller fibre machines mark and engrave stainless steel, aluminium, brass and anodised metal — think engraved metal tags, tools and jewellery. Large industrial fibre lasers cut thick sheet steel in factories, often in a shower of sparks.
Which one for which job?
- Wood, plywood, acrylic, leather, cork: CO2, or diode for wood and leather.
- Metal tags, jewellery, tools: fibre.
- Clear acrylic: CO2 only.
Whatever the machine, the job always starts as a file on a computer — see from sketch to laser file.
Photo: Cemrecan Yurtman / Unsplash
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