| The wavelength of TEA CO2 laser radiation is in the spectral range of 9-11μm and within atmospheric window. It is widely used in pollution monitoring, pumping far infrared laser and industry processing. Especially the miniature tunable TEA CO2 laser which is small and light can be used in many fields. It is a perfect optical source of pollution monitoring lidar. Using isotope CO2 as laser medium the spectral range of laser is widely extended. When isotope TEACO2 laser is used in LDIAL, the following merits exist: 1. Because the CO2 isotope laser extends the spectral range of CO2 laser, the lidar using CO2 isotope laser can enhance the amount of detectable atmospheric pollutants. 2. The central wavelength of the CO2 isotope laser is different from that of the 12C16O2 laser, so that the laser using the CO2 isotope as the active medium can reduce the absorption caused by the atmospheric 12C16O2. This characteristic develops the longer operation range of pollution monitoring lidar. Based on this background, a miniature tunable TEA 13C16O2 laser is researched from theoretical and experimental aspect in the dissertation.The theoretical studies in the dissertation are the researches on the output character of the TEA 13C16O2 laser using two methods: 1. Discrete Variable Representation (DVR) technique is used to calculate the ro-vibrational energy level, the emission lines in 0001-1000 and 0001-0200 bands and the corresponding Einstein spontaneous emission coefficients of 12C16O2 and 13C16O2. So the small signal gain of different emission lines is calculated from the Einstein spontaneous emission coefficients. Compared the results of 13C16O2 with 12C16O2, it is found that the small signal gain in 0001-1000 and 0001-0200 bands of 12C16O2 is similar, but the small signal gain in 0001-1000 band of 13C16O2 is about twice as much as the gain in 0001-0200 band. 2. The gain switched six-temperature technique is used to calculate the cavity-field intensity, laser output pulse, inverse population, small signal gain of the miniature TEA 13C16O2 laser. The influence of gas pressure, gas temperature, undissociated coefficient and electron pump density on the output energy of TEA 13C16O2 laser is researched.The experimental research in the dissertation consists of two stages. Firstly, the magnitude of laser output energy affected the number of TEA CO2 laser emission lines. To increase the laser output energy, the following means are attempted in the experiments: 1) The laser active volume is enlarged. 2) The different excited circuits are attempted. 3) The optimal magnitude of the peak capacitance and the storage capacitance is studied. 4) The optimal work pressure is researched. 5) The additive gas is added. When peak capacitance is 5.4nf and storage capacitance is 24.3nf, the maximum energy of 540mJ is obtained by using gas mixture CO2: N2: He=1: 1: 3 at 85.3kPa. When peak capacitance is 2.28nf and storage capacitance is 13.5nf, the maximum energy of 409mJ and 69 emission lines are obtained by using gas mixture CO2: N2: He=1: 1: 3 at 66.6kPa. The effect of additive gas H2 and Xe on the output of TEA CO2 laser is researched. The output energy of TEA CO2 laser is improved when proper H2 is added to the gas mixture, but the output energy is not improved when Xe is added to the gas mixture. Secondly, based on experiments in the first stage, peak capacitance of 2.28nf and storage capacitance of 13.5nf are used, when the experiments on output of isotope TEA 13C16O2 laser are carried. At gas pressure of 64kPa, the maximum output energy of 357mJ and 51 emission lines are obtained. The effect of the additive gas H2 on the TEA 13C16O2 laser output character is researched. At the gas pressure of 80kPa, the gas mixture 13C16O2: N2: He=1: 1: 3+1% H2 is used to obtain maximum output energy of 407mJ and 57 emission lines. The output energy and the number of laser emission lines are increased.
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