Relation Between Discharge Length and Laser Pulse Characteristics in Longitudinally Excited CO2 Laser
- First Online:
- Cite this article as:
- Uno, K., Dobashi, K., Akitsu, T. et al. J Infrared Milli Terahz Waves (2013) 34: 225. doi:10.1007/s10762-013-9966-6
A longitudinally excited CO2 laser pumped by a fast discharge emits a short laser pulse, similarly to TEA and Q-switched CO2 lasers. We investigated the relation between the discharge length and the laser pulse characteristics to develop a longitudinally excited CO2 laser producing a high spike laser pulse. We examined discharge lengths of 30, 45, and 60 cm, using the same mirrors and the same excitation circuit with the same input energy. A longer discharge length increased the discharge volume and improved the laser output energy. However, the longer discharge length caused a long discharge formation time (a slow fall time of the discharge voltage) due to the higher discharge impedance, which resulted in a long laser pulse tail. Therefore, the longitudinally excited CO2 laser had optimum conditions for obtaining a high spike laser pulse effectively.