Optimal Design Of Radio-frequency Excitation For Prism Laser Gyro

Laser gyro excitation technology is one of the key technologies in the laser gyro application.At present,the mature laser gyro excitation technologies include DC High Voltage Discharge(DCD)and High Frequency Discharge(HFD).Among them,DCD technology is widely used in various reflective laser gyros.However,the high voltage of DCD technology will lead to heat accumulation in the gain medium,resulting in serious autothermal effect.The study found that when DCD technology works,the heat generated by the autothermal effect is 30 times that of HFD technology.When laser gyro works,it pursues long-term stability.Therefore,it is more suitable for the laser gyro to adopt HFD technology to realize gain medium activation.It is of great significance to systematically study HFD technology in laser gyro application.In this thesis,the optical stress harmonic curve of prism laser gyro needs to be stabilized,the electric field distribution of laser gyro using RF excitation is studied,and the RF excitation source is designed.The discharge parameters in helium neon tube of laser gyro were simulated by finite element method considering the main factors affecting discharge in laser gyro and changing the relevant parameters such as RF frequency,RF voltage,electrode size and electrode tilt Angle.Further,the photoelectric characteristics of prismatic laser gyro during radio-frequency discharge are studied,and the relationship among discharge parameters such as radio-frequency frequency,radio-frequency electric field and laser gyro optical power is established.The gain pumping experiment platform of prism laser gyro was built,and the output power of laser gyro RF discharge was collected by adjusting RF frequency,RF supply voltage and other related parameters,and the special rule of RF discharge parameters was verified.The main research contents of this thesis include:1.Based on the analysis of the working principle of HFD excitation,a new HFD excitation circuit is designed,which can fine tune the frequency of HFD excitation and ensure that the laser gyro can be powered at a stable RF frequency in the experiment.2.Based on one-dimensional diffusion approximation equation,a physical model of laser gyro plasma RF discharge is established.According to theoretical calculation and simulation analysis,discharge parameters of laser gyro excitation at different frequencies and different RF voltages are collected,and the internal relationship between model parameters and plasma discharge is studied.3.Set up the gain pumping experiment system of prism laser gyro using RF excitation to observe the change of laser gyro output power under different RF frequencies and different RF voltages.Combined with the experiment and simulation,it can be concluded that the optimal conditions for the RF discharge of 0.47 m prism laser gyro are as follows: 135 MHz RF frequency,7V RF voltage,electrode anode size 23mm*1mm*10mm,electrode cathode size16mm*1mm*10mm,upper and lower electrode spacing 3mm,and parallel structure of upper and lower electrodes.The conclusion provides theoretical and research basis for the optimization design of RF excitation technology of prism laser gyro.The research results provide theoretical basis for the optimization of laser gyro RF excitation source,and guide the design of this kind of laser gyro excitation source.