Initial study of the gain characteristics of a CO2 laser amplifier
Abstract
A single pass amplifier with a flowing active gain medium of carbon dioxide (CO2), nitrogen (N2) and helium (He) gases was investigated. The dependence of the ampifier gain on the total and partial pressure, gas composition, input power and current intensity through the ampfifler was established experimentally. The experimental setup used in determining the gain at optimized parameters is shown.
The oscillator used was a water-cooled sealed-off CO2 laser with an output power of 14.2±0.19 Watts at an operating current of 18 mA. The percentage efficiency at this current is approximately 13.2%. A 100.2 cm amplifier tube with a bore radius of 0.8 cm was used. The optimum gas mixing ratio which corresponds to the highest gain was found to be 1:1:8 CO2-N2-He mixture. The maximum gain measured was 1.68 at a total pressure of 25 torr.