A Model of a Repetitively Pulsed Sealed-off CO2 Laser
N. Khan, N. Abas, A.R. Kalair and N. Mariun
This paper reviews four, five and six temperature distribution models for continuous wave (CW) and pulsed CO2 lasers. Theoretical work focuses on four-temperature model of Scot and Mayers for improving the performance of sealed-off CO2 lasers. This work investigates the correlation between energy modes and intra-cavity optical intensities at equilibrium for optimal solutions. An energy balance equation involving terms like load, temperature of the discharge tube wall and optical power is mathematically derived. The variation in the output power as a function of parameters in the energy balance equation is predicted. Theoretical and experimental results are compared with published data to validate proposed modifications. This model is general for all types of gas lasers, but specifically optimized to predict the performance of sealed-off CW CO2 laser. A few modifications in previously published data are outlined and new solutions are discussed to make the new model more effective and accurate. Four, five and six temperature models of CW and pulsed operations were transformed into a general model for repetitively pulsed sealed-off CO2 laser. Sealed-off CO2 laser output steady-state power and pulsed energies as a function of the discharge currents are reported in light of four temperature model.
Keywords: Sealed-off CO2 laser, pulsed, continuous wave (CW), mathematical model, temperature distribution model