| The laser-induced damage to optical components has always been the main limitation for development of high energy and high power laser system.Therefore,the study on laser-induced damage mechanisms and the improvement of damage threshold of optical components are always the most important problems in high power and high energy laser technology.However,the laser damage mechanisms of optical materials include thermal damage,avalanche ionization,multi-photon ionization,impurity-induced damage,nonlinear effects and so on.The damage phenomenon and mechanism of laser-induced damage are related to wavelengths and pulse widths of laser beams.The methods of laser-induced damage detection are quite different due to the complex process of laser damage.Traditional methods include phase contrast microscopy,scattered light measurement,plasma spark,scanning electron microscope and so on.However,all the above methods can not realize the efficient,accuracy,compact,low-cost and real-time detection simultaneously.For solving the above problems,the effective,compact and real-time photo-acoustic method is used to detect the laser-induced damage characteristic of fused silica and K9 glass in this thesis.It may provide a useful tool for laser induced damage phenomenon detection.A photo-acoustic detection experimental platform with simple structure,compact,convenient,real-time is built,in which the photo-acoustic probe is used to collect the photo-acoustic signals.The laser-induced damages of fused silica and K9 glass have been detected with the laser system with pulse width of 10 ns and wavelength at 1064 nm in the 1-ON-1 procedure.The results of laser damage threshold measured by the photo-acoustic are in good agreement with that of the microscope method.The phenomenon is detected with photo-acoustic method,and the damage threshold of fused silica and K9 glass is calculated with 0%damage probability and equal to about 10.9 J/cm2 and 11.1 J/cm2,respectively. |
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