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Carbon-Dioxide Lasers

Carbon-dioxide (CO₂) lasers are powerful and comparatively efficient gas lasers emitting at 10.6 µm or at other wavelengths around 9-11 µm. A gas discharge excites nitrogen molecules, which transfer their energy to the laser-active CO₂ molecules.

CO₂ lasers of different types span a wide range of powers-from tens of watts to many kilowatts or even several megawatts. While low-power versions can work with a sealed tube (no-flow lasers), high-power lasers use a fast gas flow. Continuous-wave and pulsed operation are possible.

Even at high power levels, CO₂ lasers often reach nearly diffraction-limited beam quality. Due to the longer wavelength, the beam parameter product is larger than that of diffraction-limited solid-state lasers (e.g., thin-disk lasers), but it is still smaller than that of many solid-state lasers with nonideal beam quality. The figure above gives a rough indication of the typical parameter regions.

Properties of Carbon-Dioxide Lasers