UV vs CO2: Which is the best for laser engraving glass?

CO2 glass etching isn’t as permanent

Because with a CO2 engraving the glass is being fractured, it leaves behind small shards from the ablation process. This means over extensive use, or for example after being washed several times, the mark will fade as the shards break away.

So, for barware and consumer-grade glassware, any mark you put on there will be lost after a few runs through a dishwasher.

UV lasers can mark with much finer detail

In general with lasers, the longer the wavelength, the larger the spot size. Spot size is the size of dot the laser fires at the glass, like a fine paintbrush against a paint roller. Larger spot sizes, like CO2 lasers, are good for speed, but bad for detail.

CO2 has a very long wavelength of 10.6 microns. UV has a short wavelength of 355nm – this means UV has a spot size around 30 times smaller than CO2.

In fact, Lotus UV lasers use a specialised optic that makes the spot size even smaller than typical UV laser machines, for incredible detail that’s hard to find with other machines.

If you want to mark with precision and detail, a Lotus UV laser is ideal for its accuracy and small spot.

Long preparation means slow production…and unhappy customers

Glass needs a lot more preparation if you’re going to engrave it with a CO2 laser. To protect the glass from the intense heat of a CO2 beam, it’s common to add some kind of masking fluid or tape before starting the mark.

But if you have to add this for every single mark, this wastes a lot of time if you want to mark glasses on a commercial scale. Plus, without removing (and possibly damaging) the tape, you won’t know if the engraving worked properly.

With UV lasers, there’s no preparation work needed. Ideally the glass should be clean, but engraving the glass on a Lotus UV laser is as simple as putting it on the t-slot table and pressing go.

This means production is much faster with a Lotus UV laser than a CO2 laser.

Talk to us and book a demo

We’ve been refining our laser engraving machines for over thirty years, and we were one of the first companies to fully adopt UV for glass engraving.

Many companies won’t even recommend or sell it even now – despite it being by far a better solution than CO2 or diode etching.

So, if you want clear advice and to see a glass marked with Lotus UV right before your eyes, you can always reach out to us and talk through what you need.

See our range of Lotus UV Laser Machines

Lotus UV engraves with incredible detail, but the UV is just the source.

That laser source goes into the Meta-C, Meta-XY, Personalase, and more!

So if you’re looking for a UV laser marking machine that’s right for your needs, whether you need to mark dozens of glasses or hundreds, you can see our range of UV machines and send us a message when you’re ready.

Find out more about glass engraving

If you’re still keen to find out more about glass engraving, we’ve got some more information in our applications section.

From there, you can read more about the best way to engrave glass, whether you’re working with drinkware, electronics, or glass fixtures.