| High speed photography plays a very important role in the high speed process such as status of high speed moving object and laser processing and chamechal reaction etc. High speed photography plays a very import role in military and civil applications and can be used in different area. High speed photography has a strict requirement for light source. The lightness of the light source can affect the quality of photography directly. High frequency electro-optic q-switch laser is one of the most selective light source.we researched the laser system based on Nd:YAP crystal as working media..Firstly, the crystal characteristics, energy level structure, absorption spectrum and heat effect has been studied. In order to understand the characteristics of laser in which Nd:YAP as working media, continues wave Nd:YAP laser has been designed by using diagram technique and important character and data has been obtained. Based on the data obtained theoritcal and experimental research has been accomplished for the continues and pulse laser in which Nd:YAP crysital as the working media. Lamp pumped pulse laser and 100 kHz converting frequency constant current charging power supply has been designed. Charging precision that affect stability of laser output has been discussed. Nd:YAP Laser that has 300 mJ output pulse energy,1Hz repeat frequency and 500μsμpulse width has been developed successfully.Secondly, based on four energy level system mode we solve the four energy level q-switched rate equation, we obtained the relationship of repeat frequency q-swiched laser output characteristics. We obtained output energy, build up time, pulse width by deliverying experiments and relation curve among them have been ploted. High frequency q-switched laser system has been calculated. Since the laser output stability has been the most difficult problem to solve the dissertation analyzied optic-elastic factor deeply and generate stable laser output by adopting efftive methods and realized 150 kHz pulse sequence by using pulsed transmission mode q-swithing.Finally, in order to meet the requirement light source power of high speed photography we designed multistage power amplifier. The laser system including master oscillator and two stage amplifier has been built, laser pulse in which wave length is 532 nm and sing pulse energy is1.36 J was aquired. Theoretical and experimental study for unstability of laser output has been delivered. Various unstable factor has been solved and meet the requirements of ligh source of high speed photography.The experiments of high speed photography proved that high frequency q-switched laser system fully satified the requirements of high speed photography. |
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