| The RF slab has a broad application prospect with characteristics of good beamquality, high electro-optical conversion efficiency, compact structure and good thermalstability. The research of electrode coating technology and discharge control technology ofthe RF slab CO2laser has been carried out in this thesis. The main content includes:（1） Sol-gel coating experiments have been carried out. Isobutanol aluminum is usedas precursor, water as solvent and nitrate as peptizator. Phase tests show that the coatinglayer is of single crystal phase of α-Al2O3. Spectrometer tests show that the reflectance ofthe film is pretty low.（2） CVD coating experiments have been conducted. The experimental programincludes AlCl3, H2, CO2as reactants, H2S as catalyst. Alumina film is obtained on thecopper surface at800°C. The reflection rate of incident light at the wavelength of10.6μmis85%, EDS and phase tests show that, the film is mixed crystals of α-Al2O3and γ-Al2O3.（3） Magnetron sputtering coating experiments have been conducted. Magnetronsputtering method is utilized to get alumina film on copper surface, and then the coatinglayer is oxidized in the discharge case. The reflection rate of the incident light can meetthe requirement of CO2laser. Experiment has been carried out with the coated electrode, itshows that the laser can reach high output power with uniform and stable discharge.（4） A set of power control system has been designed. MCU is used as themicroprocessor, CPLD is used as PWM waves’ generator. Input signals can be analogsignals, digital signals, and signals from PLC and PC. By generating PWM waves whichare tunable in duty cycle and frequency and changeable in operating mode, output powerof laser can be controlled in real time.Waveguide coatings can improve uniformity of RF discharge, reduce waveguide loss,thereby the laser’s output power and its working stability can be enhanced. The research ofthis thesis is significant for promoting self-development of RF slab CO2lasers. |
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