Theoretical Research On α-RF Discharge Of Oxygen

In the field of the researches on the oxygen iodine lasers and oxygen discharge plasma, RF discharge is becoming the focus and is widely used. In contrast with other discharge modes, it's no corrosive and clean, with its high stability and uniformity. Researches on RF discharge are confined to a problem that it's difficult to increase the production of singlet delta oxygen, although much progress is made in theories and experiments. So it must be improved.In this thesis, theoretical research onα-RF discharge of oxygen is mainly illustrated because of lower energy loss and higher excitation efficiency. First of all, advantages of RF discharge of oxygen are declared. Then, it makes analysis of RF power supply system in lasers: the RF power supply is designed; the load and the impedance matching network which connects the power supply with the load are also discussed and calculated. An experiment of comparing DC discharge with RF discharge is carried out, and the result of latter is absolutely better. A theoretical model of oxygen RF discharge in the slab laser is established according to the characters of capacitive RF discharges. The discharge plasma characteristics which are intimately related to production of singlet delta oxygen are explained after numerical solutions in three conditions: pure O2, mixture of Ar and O2, mixture of He and O2. So the spatial distributions of electric field and electron density are obtained. Analysis on the parameters can benefit for generation of singlet delta oxygen. At last, the energy levels and spectra of atomic oxygen and molecular oxygen are showed. Measuring the oxygen laser plasma discharges with a grating spectrograph and handling the data with a computer, the emission spectra are obtained. Based on the atomic transition spectra, decomposition of atomic oxygen and how to generate the discharge plasma are realized. So the electron energy can be estimated.