The Study Of The Q Technology On RF CO₂ Laser

Pulsed CO2 laser has been widely used in many areas because of its uniqueness, and the Q-switched technology producing pulsed laser has obtained considerable development. In order to obtain high frequency, narrow pulse width and high peak power small sealed RF CO2 laser has been modulated by Mechanical Q-switched technology, Acousto-optically Q-switched technology, electrooptically Q-switched technology and Cavity-dumped technology. The electrooptically Q-switched and Cavity-dumped process has been simulated.Abundant investigation about the development of the three active Q-switched technologies has been made in this thesis at first. Besides, the existing small sealed RF CO2 laser in the laboratory has been modified slightly in order to facilitate subsequent experiments.Characteristics of pulsed laser produced by Mechanical Q-switched technology and Acousto-optically Q-switched technology inside the cavity has been analyzed such as the pulse waveform(pulse width and the tail)?frequency and output power(average power and peak power). The change of the characteristics mentioned above has been observed by changing the modulation frequency and the open time.Electrooptically Q-switched technology and Cavity-dumped has been used to obtain the laser with narrower pulse width but similar repetition frequency and peak power. The electrooptically Q-switched technology includes pressurized and piezoelectric electrooptically Q-switched technology. The change of the results have been observed by adjusting the open time?modulation frequency and the voltage. In order to make the pulse width narrower, a B's window has been added to the cavity-dumped electrooptically Q-switched apparatus and the experimental parameters have also been changed to detect the change of the results.Four-level model has been used to simulate the process of electrooptically Q-switched technology. Cavity-dumped process has been simulated by describing the the influence to the reflection of B's window by the change of the resonant cavity optical polarization direction with a function. Besides, parameters have been adjusted to observe the change of the simulated results. The difference between the theoretical and experimental results have been analyzed.The pulsed laser with certain ranges of repeat frequency, peak power and pulse width has been obtained by using the methods mentioned above in the small sealed RF CO2 laser, which can be a reference to obtain needed pulses from different lasers.