The theory behind how lasers work dates back over 100 years. Einstein’s work on the Photoelectric Effect won him the Nobel Prize; not for Relativity as most people assume. Ted Maiman, while at Hughes Aircraft, built the first working laser using synthetic ruby over 50 years ago.
Consequently, lasers have become powerful tools of the modern age and find use in telecommunications, holography, eye surgery, and bar code scanners. Several types have even found their way into printing as described below.
Types of Laser
The variety of lasers spans output in short X-ray and UV wavelengths through the visible to the longer infrared (IR). Laser light can be steady or pulsed with very low power to very high energies. Wikipedia has an extensive List of Laser Types.
Laser Etching and Printing
There are several kinds of IR laser than can etch or print. CO2 (carbon dioxide) and glass fiber doped lasers are two types. The latter uses rare earth elements such as neodymium, the same rare earth metal found in neodymium magnets. These two lasing media produce infrared light at different wavelengths. Near-infrared (NIR) is the shorter wavelength and whereas far-infrared (FIR) describes the longer wavelengths. The wavelength determines what can be printed and how.
A CO2 laser works well for marking glass in prisms and magnifying glasses. A laser beam scans back and forth and removes a thin layer of glass which produces a frosted effect. You can see the process in the video below. This type of laser cannot engrave lab glassware which is made with heat resistance borosilicate (“Pyrex”).
The fiber optic laser can ablate the black anodized layer on brass which is used in our metal linen testers. The fiber laser outputs at a relatively short IR wavelength which allows it to produce much finer etched lines. Compared to a CO2 laser, this is the infrared laser equivalent of high definition. View the process in the video below.
Laser-etched products include metal linen testers done with a fiber laser and hand magnifiers and glass prisms with the CO2 laser. Compare the greater detail produced by the fiber type as seen on the metal linen tester to the hand magnifier.
Why Choose Laser Etching?
We offer a variety of custom imprint methods including silk screen printing, decals (stickers) and laser etching; all outlined in our Branding section. Each has its merits ranging from fine details to multicolor. Laser etching by its nature is one color but is also the only truly permanent imprint method.