Co2 Laser Vs Diode Laser: Which One Is Right For You?

By Author: steven glassner
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For years now, there have been debates over which laser is better: a diode laser or a Co2 laser? Which machine to choose? Which technology is better? Why? And many such questions follow.

These two technologies are worlds apart and have all the differences in the world. The only thing common between them is laser radiation. And maybe the parts they use like Trumpf spare parts and Mitsubishi spare parts.

But before we understand the difference between them, let’s start first understanding these laser machines.

What is a CO2 laser?

It stands for carbon dioxide laser and is a molecular gas laser made of the gaseous mixture as the gain medium.

It contains CO2, helium (He), nitrogen (N2), and some amount of hydrogen (H2), water vapor, and/or xenon (Xe). Such a type of laser electrically pumps via an electrical gas discharge. It operates either using DC current, AC current, or in radio frequency (RF) domain.

Nitrogen molecules excite using electric discharge into a metastable vibrational level and transfer this energy to ...
... CO2 molecules when it collides with them.

What is a Diode laser?

To know about diodes, let's go back to old times when Albert Einstein first defined the principle of stimulated emission in 1917. It states that an excited electron or molecule can deliver energy in the form of light. It also shows that an excited electron or molecule can deliver energy in the form of light.

The emission triggers upon supplying energy in the form of light. This stimulated emission triggers by supplying energy to an ideally light amplifying material that delivers energy in the form of light. This form of energy supply is pumping.

When electrons or molecules fall back into their initial state, the energy delivers as a light beam.

Now, let’s understand the difference between both of them:

1. CO2 laser:

The biggest advantage of a CO2 laser is that it is raw laser power. The smallest tube machines have 40 to 80 watts output power. Whereas, professional and industrial units have up to 150 watts.

The benefit of industrial units is that they can reach up to 400 watts. That is a huge amount of power and is suitable for cutting any material except metal. And with the right parts like Trumpf spare parts and Mitsubishi spare parts, you can utilize Co2 laser to highest efficiency.

Hence, if you are looking for a laser machine for industrial production then having a CO2 laser is a perfect choice.

The CO2 laser works on a particular wavelength of 10.6uM. It is longer in comparison to the light spectrum.

Spectrum matters because the far infrared spectrum does not work for all the materials. For example, Co2 laser might help you to cut glass and transparent Plexiglas well, but with this amount of wavelength, you cannot engrave metals without special paste.

Most of the materials have a high absorption coefficient of this wavelength. This makes it easy for cutting and engraving any material.

Similar, to every technology, Co2 laser has limitations too:

The key problem with co2 laser machines is the size. These machines are very huge and bulky. Additionally, the Co2 tube requires much space as well. In short, it occupies lots of space. Size matters when you are working in a garage or have a small workshop as most of the small scale businesses or hobbyists do not have enough space.
Another limitation is that it is not transportable. As the machine is huge and heavy, moving it from one place to another makes it difficult and costly.

Going further, let’s flip the coin and look at the limitations of diode laser machines:

Diode laser beams are divergent i.e. wedge-shaped, instead of straight and parallel. They have a short and coherent distance that is made of inferior quality optics performance.

They are not well-suited as helium-neon lasers for a high quality of holography. Additionally, semiconductors in electronic devices are prone to static electrical discharges; this means that diode lasers in these gadgets can be damaged by an unstable and fluctuating power supply.

They are also vulnerable to gradual aging over time and increased amounts of power with diminishing efficiency. But if equipped with quality parts like Trumpf spare parts and Mitsubishi spare parts, then you can rely on this laser machine for a good amount of time. There is also a requirement for beam correction that adds to the diode lasers’ fragility.

Final words:

Going beyond the benefits and limitations of Co2 and diode lasers both of them are useful depending upon the needs of your business. These machines make life easy for fabricators and help them to grow their business easily.

Steve M Glassner is the General Manager of Alternative Parts Inc, the leading manufacturer and distributor of Amada machinery replacement parts. Steve is a Machine Tools industry enthusiast and frequently writes about various aspects of the industry.