CO2 lasers produce light at a 10,600nm wavelength, which is absorbed by water in the tissue. The laser energy heats up the water until it reaches a boiling point causing the evaporation of the affected tissue. Some heat is absorbed by tissue adjacent to the ablated target area, causing tissue coagulation which induces hemostasis (the cessation of bleeding) as well as thermal stimulation of deep skin layers, which induces fibroblast stimulation and neocollagenesis (the formation of new collagen).
The laser beam can also be transmitted through a scanner which is a device used to further control the delivery of energy. The scanner regulates the configuration of energy delivered onto the skin, which can range from covering the entire treatment area or just a fraction of it (leaving the areas in between untreated); (also referred to as fractional ablation). The overall effect of ablation and coagulation, either full or fractional, is the removal of skin and the stimulation of the body to replace it with newer, younger skin.