How Are Plaques Engraved?

Ever wonder how your plaques are engraved?  Well, the answer is actually pretty cool and has evolved over the years.  For many years, awards were engraved with rotary engravers which required a rotating tool with (usually) a diamond tip to actually touch the material being engraved.  The process was slow but worked well on many materials.

Now most awards are engraved using CO2 lasers. These machines are fast and efficient and run by computers. CO2 lasers work by using a mixture of gases (carbon dioxide, nitrogen, and sometimes helium or neon) to produce an intense, coherent beam of light in the infrared part of the spectrum. The laser works by using electrical energy to excite the gas mixture inside a sealed tube, which then produces light.

Here’s a basic explanation of the process:

1. The laser tube is filled with a mixture of gases, including carbon dioxide, nitrogen, and sometimes helium or neon.
2. The gas mixture is excited by an electrical discharge, which creates a population inversion in the energy levels of the gas atoms.
3. The excited atoms then release their excess energy as photons, which are coherent and have the same phase and frequency. This is known as stimulated emission.
4. The photons are reflected back and forth through the laser cavity by two mirrors, one of which is partially reflective, so that some of the light escapes as the laser beam.

• The laser beam can be focused and directed by optics to cut or engrave the award. Many materials can be engraved using CO2 lasers including marble, glass, crystal, acrylic, wood and specially treated metal.

If you ever get a chance to see one in action, I recommend it.