We use a Coherent DEOS GEM select 100 single mode CO2 laser. The laser emits a 100 W horizontally polarised beam
Principle of Operation
Briefly, there is a
mixture of CO2, N2 and He gases contained between electrodes in the gain
region of the cavity. An RF field is applied between the electrodes which
creates a discharge. The first vibrational mode of the N2 molecules (which
has a very large excitation cross-section) is excited. This state is metastable
and close in energy to the first asymmetric stretch mode of the CO2 molecules.
The CO2 molecules are excited due to collisions with the N2 (collisions are
augmented by the presence of the He). The first asymmetric stretch mode
of the CO2 molecules decay to the first symmetric stretch mode, resulting in
laser output at a wavelength of 10.6 Ám.