Studies On Mechanical Q-switched CO₂Laser

In the history of laser technology, the development of Q-switched technology isimportant. The technology of Q-switch has promoted the nonlinear optical developingthrough the interaction between Q-switched pulses and materials. Q-switched technologyalso made great developments of laser rangefinder, lidar, high-speed photographyholographic and so on. So lots of attentions were focused on Q-switched technology. In thisthesis, the mechanical Q-switched CO₂laser output characteristics were studied and someresearch work were carried out on laser resonator experimentally and theoretically.Firstly, the thesis introduced some investigations on Q-switched technology. Then amechanical Q-switched CO₂laser was designed according to the requirements o f EUV（extreme ultraviolet） project.In this study, the influences of rated power, laser repetition frequency, chopper incisionwidth of the film, and other parameters on properties of the mechanical Q-switched CO₂laser, such as output pulse waveform, average power, pulse width and peak power, wereinvestigated in detail in order to obtain a perfect mechanical Q-switched CO₂laser. From thecalculated results of the stability of the resonator cavity, it can be concluded that theresonator cavity we used was stable. Based on the calculated results of the Beam Spot of thelaser in the cavity, the parameters of the cavity were obtained, meeting the requirements ofEUV project. And a laser with the peak power40kw, pulse width of about250ns wasobtained.The results we obtained in the study of the mechanical Q-switched CO₂laser can bereferred and applied for next investigations on electro-optical Q-switched CO₂laser of theproject.