Experimental investigation of the effects of the gas mixture on the CO2 lasers Pulse shape

This work investigates the effects of different operational parameters on the pulse shape of a homemade high repetition rate (1 kHz) pulsed CO2 laser. Various parameters such as the ratio of N2 and He in the laser gas mixture and the reflectivity of the laser front mirror have changed. Then, the energy and shape of the laser pulses were recorded and analyzed. It showed that by varying the ratios of N2 and He in the laser gas mixture, the time duration of the spike and tail parts of the laser pulses can be changed in 95-140 ns and 1.5-3.5 µs range, respectively. In addition, we found that when the reflectivity of the cavity front mirror increases from 50% up to 80%, the spike duration increases from 50 ns up to 90 ns, and the tail duration decreases from 4.8 µs to 2.5 µs.