How does the CO2 laser engraving glass? - Blog -Perfect Laser Co., Ltd.
Home > blog > How does the CO2 laser engraving glass?
How does the CO2 laser engraving glass?
2016-08-05 by bridge

You can always hear or see lots of talk at tradeshows and workshops about using a CO2 laser to mark glass. Sometimes the information is accurate and sometimes salespeople get a little carried away with their claims. The editor of Wuhan Perfect Laseris intended to share our nearly 20 years of experience as to what lasers will and will not do when working with glass.

Each type of laser works at a specific frequency. That frequency range (wavelengths of the light produced by the laser) determines what the laser will and will not cut. A YAG laser may operate identically to a CO2 but the frequency is different, it will affect materials in a completely different way. There are any number of different frequencies used by lasers and each determines what it does best.

In the most basic of terms, glass is made by heating silicon (sand). When heated hot enough, the silicon melts and becomes a thick, gooey fluid. This can then be poured into molds or blown by hand. As the molten glass cools, it remains transparent. To add strength or color to the glass, other elements are added. These are often metals such as lead, zinc, cobalt or even pure gold. It’s the air and moisture that’s trapped within the glass that makes laser marking possible with a CO2 laser.

As a laser beam strikes the glass, it heats up the glass elements including the silicon and any metal content but neither of these elements will react to the relatively low heat and frequency of a CO2 laser. What does react is the air and moisture trapped between the elements of silica and metal. Both water and air expand when heated. Because the glass itself is relatively rigid, when molecules within the glass are heated until they expand, something has to give to allow for the expansion. This results in microscopic fractures in the glass, especially at the surface of the glass. It is this chipping or fracturing that we see as engraving.

keywords:    CO2 engraver and cutter



This is Helen from Perfect Laser. Welcome to text me on WhatsApp or send me an email to

× Text me on whatsapp