Er:YAG laser giant-pulse generation

摘要

Three possibilities of mid-infrared Er:YAG lasers Q-switching were investigated: mechanical and two electro-optical ones. The mechanical method of Q-switching was proved by using of a rotating mirror placed inside the resonator; Pockels or Kerr cells were used for the electro-optical Q-switching. The Pockels cell was constructed on the basis of the Brewster angle cut LiNb03 crystal; the Kerr cell used a ceramic PLZT material. In all the three cases the Er:YAG laser resonator was plan parallel and it consisted of the rear copper mirror and output coupler with 50-70% reflectivity. The Er:YAG crystal was pumped by one xenon flashlamp in a single elliptical silver coated cavity. The generated giant pulse output parameters were the following: the length was measured in the range of 200-400 ns; the output energy was from 10 mJ up to 30 rnJ. With the rotating mirror the output was stable in a wide range ofthe switching interval. All the three cases can be used in applications. The particular Q-switch can be chosen from the point of view of output parameters and construction requirements.