CAJ | 학술논문

为了研究TEA CO2激光重复频率对远场光束特性的影响，首先采用有限元方法计算了不同重复频率下反射镜的温度场和热变形分布，然后采用协方差矩阵法对镜面热变形进行了Zernike拟合，最后结合衍射的角谱传播理论和功率谱反演法分析了不同重频TEA CO2激光经过内光路热畸变作用后的远场光束特性。研究表明：在净吸收能量相同的情况下，随着重复频率的增大，反射镜的温度逐渐升高，热变形量逐渐增大，经过内光路热畸变作用后，远场光束的Sr和平均能量密度Ed逐渐减小，参数逐渐增大，光束质量逐渐变差；对于TEA CO2激光，重频为300 Hz的Ed值仅为10 Hz的40%，远场光束的峰值光强下降了43%，光斑展宽了近60%。文中的研究结果为TEA CO2激光发射系统的优化设计提供可靠的依据。
위료연구TEA CO2격광중복빈솔대원장광속특성적영향，수선채용유한원방법계산료불동중복빈솔하반사경적온도장화열변형분포，연후채용협방차구진법대경면열변형진행료Zernike의합，최후결합연사적각보전파이론화공솔보반연법분석료불동중빈TEA CO2격광경과내광로열기변작용후적원장광속특성。연구표명：재정흡수능량상동적정황하，수착중복빈솔적증대，반사경적온도축점승고，열변형량축점증대，경과내광로열기변작용후，원장광속적Sr화평균능량밀도Ed축점감소，삼수축점증대，광속질량축점변차；대우TEA CO2격광，중빈위300 Hz적Ed치부위10 Hz적40%，원장광속적봉치광강하강료43%，광반전관료근60%。문중적연구결과위TEA CO2격광발사계통적우화설계제공가고적의거。
In order to study the influence of TEA CO2 laser repetition frequency on far-field beam quality, the temperature field and thermal deformation distribution of the mirror were calculated firstly by the finite element analysis of thermodynamics instantaneous method with TEA CO2 laser irradiation of different repetition frequencies. Then, mirror thermal distortion was fitted by Zernike polynomials. Finally, far-field characteristics of different repetition frequencies TEA CO2 laser were obtained by the angular spectrum propagation theory of diffraction. The theory and simulation results show that with the increasing of laser repetition frequency, the mirror temperature and thermal deformation are gradually increasing. After thermal deformation effect, Sr and the average energy density Ed decrease, and parameter gradually increases in the far field. Comparing with 10 Hz, Ed of 300 Hz decreases 40%, peak power in the far field decreases 43% and beam waist broadens 60%. When the laser repetition frequency is greater than 100 Hz,due to the appearance of peaks and valleys on the mirror, the far-field beam quality decreases significantly. The results of this paper can provide the reference to TEA CO2 laser launch system.