Operating Characteristics of an Optically Pumped CH2OH FIR Laser

The operating characteristics of an optically pumped 118μm CH3OH laser were examined for various parameters, such as CH3OH gas pressure, cavity length, tube diameter and wall temperature of the laser tube, in order to find their optimum conditions giving a maximum output power. The optimum CH2OH gas pressure changed with laser tube diameter and CO2 pump power, but was independent of wall temperature of laser tube. The output power increased monotonically until-40°C with decrease in the temperature and becomes 1.7 times that at room temperature. However, further decrease in the wall temperature resulted a rapid decrease in the output power.