【摘要】 研究了基波相位畸变对二次谐波相位分布的影响。针对具有不同像差、而光强分布为高斯型的光束 ,以KDP晶体Ⅰ类匹配为例 ,数值计算得到了其二次谐波光束的光强分布和相位分布 ,分析了基波的像差、离散效应以及衍射效应的影响效果。研究表明不同的像差对于谐波的影响是不同的 ,主要取决于由其引起的全口径上相位失配的情况 ;离散效应主要带来的是倾斜像差 ,其高阶像差的影响随着离散效应的加剧而增大 ;而衍射效应的影响在一般情况下都是可忽略的。最后给出了在离散效应和衍射效应的影响可以忽略的情况下 ,基波相位畸变对二次谐波影响的近似估算式更多还原

【Abstract】 The effect of aberrations of fundamental wave on second harmonic generation especially on the phase of second harmonic (SH) wave is studied. The solution is applied to type Ⅰ second harmonic generation in KDP crystal. The results of intensity distribution and phase distortion in second harmonic generation are presented when the fundamental wave are Gaussian beams with aberrations of Zernike polynomials,and the effects of different aberration,walkoff and diffraction are analyzed. It is shown that different aberrations have different effects, which is mainly determined by the phase mismatching on the whole aperture; walk off effects bring large tilt and the more serious the effect the more distorted the phase of SH is; and effect of diffraction is neglectable. The approximative formula of SH phase distortion are given when both walkoff and diffration effects can be ignored.更多还原