光斑形状对BBO晶体四倍频效率的影响  

Effect of spot shape on the quadruple efficiency of BBO crystal

作　　者：孟诗涵 臧天元 蒋剑良[1] 张恒利[1] MENG Shihan;ZANG Tianyuan;JIANG Jianliang;ZHANG Hengli(Solid State Laser Laboratory,School of Optoelectronics,Beijing University of Technology,Beijing 1ooo8l,China)

机构地区：[1]北京理工大学光电学院固体激光实验室,北京100081

出　　处：《光学技术》2024年第3期305-308,共4页Optical Technique

摘　　要：BBO晶体是一种被广泛应用于激光倍频、混频、光参量振荡等光学领域的非线性频率变换晶体。但是由于该晶体在四倍频过程中具有较大的走离角,会使产生的倍频光与基频光逐渐分开,降低了四倍频转换效率。文章模拟了在532~266nm倍频过程中,入射光斑形状为圆形和矩形时对BBO晶体四倍频效率的影响。计算结果表明,采用矩形光斑入射到BBO晶体表面可以延长有效倍频孔径长度,减小走离效应对倍频光的影响,明显提升四倍频效率。The BBO crystal is a non-linear frequency conversion crystal that is widely used in optical fields such as laser frequency doubling,frequency mixing and optical parametric oscillation.However,due to the large departure angle of the crystal during the quadrupling process,the resulting frequency doubled light is gradually separated from the fundamental frequency light,which reduces the quadrupling efficiency.The effect of the incident spot shape on the quadrupling efficiency of the BBO crystal is simulated for both circular and rectangular shapes during the 532~266 nm frequency doubling process.The results show that the use of a rectangular spot incident on the surface of the BBO crystal can extend the effective doubling aperture length,reduce the effect of the walk-off effect on the doubling light and significantly improve the quadrupling efficiency.

关 键 词：矩形光斑 走离效应 紫外激光 非线性光学 四倍频 

分 类 号：TP394.1[自动化与计算机技术—计算机应用技术] TH691.9[自动化与计算机技术—计算机科学与技术]