CO2 lasers have been used in cosmetic treatments for decades. While it is called a CO2 laser, there are other gasses involved, nitrogen and helium. Combining an electrical charge, a tube, and mirrors, are the elements in generating a laser light that can be used in aesthetic, or skin, treatments.

What are the elements of a CO2 laser

First, we start with a tube that has mirrors on each end. One mirror is a fully reflective mirror, the opposite mirror is partially reflective. This is the discharge tube.

Attached to this tube is a line for the gas mixture, electric contact, and an “exhaust” line.

The electric contacts send a current through the length of the tube. This electrical charge stimulates the nitrogen molecules, creating an “excited state”, which the nitrogen can hold for long periods of time. The vibrating nitrogen molecules then stimulate the CO2 molecules. As the number of molecules excited within the system increases above the non-excited, the state of population inversion is created.

You might think of the electric current through the nitrogen as shaking the soda can. It begins a reaction the build up energy that eventually needs to be released.

Once population inversion is achieved, the gas is ready to release the energy created by the active molecules in the form of photons. To cause this release, very cold helium molecules are released into the discharge tube. When the excited molecules come in contact with the cold helium molecules, the photons are released.

The photon light builds up in intensity as it reflects off the mirrors within the discharge tube, The photons will continue to be reflected or bounce between the two mirrors building up energy, until the light intensity is sufficient to “push through” the semi-reflected mirror in the form of a laser.

The CO2 laser can be one of the most powerful lasers. The strength of the laser output depends on the electric energy input. 20w – 100w lasers are used for machining metals, though the lasers can be 1000w or more.  Cosmetic lasers typically operate in the 30w-60w range.

Since CO2 lasers are in the invisible infrared waveband, an aiming beam is used to see where the laser will be applied.  

Why CO2 Lasers are good for cosmetic procedures

CO2 lasers operate at a10,600 nm wavelength which is easily absorbed by water. Since skin contains a high percentage of water,  the CO2 laser is great for precise, safe ablation.

The Newer cosmetic CO2 lasers use high pulse rates or scattered light beams which reduce heat damage to the skin. By reducing the potential skin damage with a pulsing laser, higher power lasers can be used and treatments are able to affect deeper tissue removal and for pronounced wrinkles and creases.

If you are looking for a CO2 laser for your cosmetic or dermatologic practice, one of the most popular on the market is the Lumenis UltraPulse Encore. If you have questions about how the CO2 lasers operate or which is best for you patients, please contact us.