| Since the rapid development of self-powered lasers,the detection methods of laser damage caused by lasers have attracted more and more researchers' interest,and the various test methods have emerged in an endless stream,which has enriched the experimental demonstration for the research of laser damage mechanism.Because of the interference of excitation light and splatter,the real-time evolution detection of pulsed laser-induced material damage is difficult,and it is difficult to determine a series of critical edge states including material physical properties.To this end,this thesis proposes the "on-line detection of damage identification via polarization spectrum imaging" method,combined with the detection principle and mathematical model of the polarization bidirectional reflection distribution function,to study the damage evolution process of the active and passive detection composite ceramics under polarization irradiation.According to the Stokes vector analysis method,the damage law of the material surface under the continuous activating illuminations of multiple laser pulses and the increase of pulse energy is analyzed.The polarization spectrum image measured in real time is compared with the damage morphology of the microscopic image,and the polarization feature image is extracted by image processing technology.The damage phenomenon and details are characterized under typical polarization parameters I,Q,U,V,Degree of Polarization(DOP)and Angle of Polarization(AOP),combined with theoretical research to establish the relationship between polarization information and damage information,and then carry out the damage mechanism analysis of composite ceramic materials.This thesis not only provides a new method for real-time detection of laser damage,but also lays a foundation for detection and identification under other strong light interference,and also provides a rich demonstration for the research of laser damage mechanism of composite ceramic materials. |
PDF Full Text Request