CO 2 Lasers

1. CO2 Lasers Theory & Conception Bax Sébastien Cortes Nicolas Jacques Jean-Charles

2. Contents • Introduction • CO2 Lasers Theory • Low power CO2 lasers • High power CO2 lasers • Conclusion

3. CO2 Lasers Theory • Vibration levels Energy storage Bending mode Symmetric Stretching mode Asymmetric Stretching mode: (001) 0.3eV Vibrational energy: Rotational energy:

4. CO2 Lasers Theory • Transfer collision resonance E=2meV<25meV CO2: 10-20% N2: 10-20% He: 60-80%

5. Low Power CO2 Lasers • Sealed C02 lasers • Regeneration of CO into CO2 • Infrared specific optic • Brewster angled windows • DC Discharge

6. Low Power CO2 Lasers • Sealed C02 Lasers • Low power output • Small Size for a CO2 laser • No heavy cost and maintenance

7. Low Power CO2 Lasers • Waveguide CO2 Lasers • Very small BeO waveguide • High pressure active medium • Radiofrequency pumping

8. Low Power CO2 Lasers • Waveguide CO2 Lasers • Yield up to 20% higher than others classical CO2 laser • High-quality beam • Can betuned to any discrete CO2 line

9. High Power CO2 Lasers • Fast axial flow lasers • Increase the gas flow • Heat exchanger • Convection • 1 kW/m

10. High Power CO2 Lasers • Fast transverse flow lasers • Gas flow controlled by a turbine (100 Torr) • The laser beam crosses the cavity many times • 10 kW/m • Poorer beam quality than axial flow lasers

11. High Power CO2 Lasers • TEA lasers • Transverse excited atmosphere lasers • Electric discharge : few tens of kV • 10 atm : broadering effects • 10 MW