You have no doubt heard of Laser engraving before. However, have you ever wondered how it works? Well, in this article I want to spell out the science behind laser engraving.
What is a Laser?
Laser is actually an acronym for Light Amplified by Stimulated Radiation. This gives a clue as to what a Laser is – it is just amplified light. The central idea is that atoms are excited by raising their energy levels (this is the Stimulated Radiation bit). As these atoms are excited more and more, they begin to release light energy. However, by careful design, the light created by each atom will have exactly the same wavelength as the light being created by other atoms. This creates a focused beam of light, that can be trained on a tiny point, allowing for precise control over what the Laser shines on.
The Laser is one of the fundamental modern technologies. It is used for a huge range of tasks: from cutting and engraving through to reading CDs and barcodes and transferring information via fibre optic cables. Each of these tasks use lasers because of the precision and control available, as Lasers can be focused with a very high degree of accuracy.
Laser Engraving – How Does It Work?
Laser engraving is a technique for using Lasers to etch or mark onto a surface. The most common method of laser engraving uses the laser to heat a tiny section of the material to a very high temperature. The Laser is mounted on a mobile head (like a CNC machine) that moves over the object to ‘draw out’ whatever it is that needs to be engraved.
The heat is so focussed and intense that the laser actually evaporates the material, leaving an indentation. As the Laser effectively vaporises the substance, there is also little to no clean up required on the material after it is engraved. A simple wipe down and finish is enough. This makes the process of laser engraving very fast.
Needham Coding use this technique to mark materials that are far too tough to mark in other ways. This method is incredibly versatile and be used to engraves a wide range of materials, from metals and plastics through to wood. This is because of the fine control achievable with Lasers. Although the heat is intense, the material is only exposed to these high temperatures in tiny pulses aimed at precisely the area being engraved. This means that the material itself is not exposed to any prolonged heating, so it will not warp or be damaged.
Another advantage is that these engraved marks are far more durable than printed marks, which can be worn away over time. This makes it an especially useful in engineering contexts, where markings on parts need to endure all the strains faced by a moving part throughout its lifecycle.
So that’s it – the science behind Laser Engraving. The only thing left for you to do is find a new DIY project where you can make use of your new knowledge! Good luck, and happy engraving.