激光与光电子学进展, 2020, 57 (15): 151403, 网络出版: 2020-08-04
平顶光束在间接驱动靶腔内的光强分布特性 下载: 695次
Light-Intensity Distribution Characteristics of Flat-Topped Beam in Indirectly Driven Target Cavity
激光光学 平顶高斯光束 间接驱动聚变 光强分布 laser optics flat-topped Gaussian beam indirect driven fusion light intensity distribution
摘要
根据ABCD传输矩阵和Collins衍射积分公式,通过光束坐标与腔体坐标间的转换关系,推导高斯平顶光束经过透镜后,激光间接驱动聚变装置腔内不同角度横截面的光场分布解析表达式,着重分析了光束入射角对焦点处及腔内光强分布的影响。仿真结果表明:增大入射光束的入射角,焦点处的光斑光强在X轴方向受到影响,光斑沿着X方向产生一定扩散,Y轴方向上的光强分布几乎没有变化;随着光轴传输距离的增大,靶腔内横截面上的光斑直径变大,均匀性变差,而且光斑位置右偏。均匀性较好的光斑与入射角度的选取及光束传输的距离有较密切的联系。
Abstract
Using the ABCD transmission matrix and Collins diffraction integral formula and by converting the relation between the beam and cavity coordinates, we derive an analytical expression for the cross-section distribution of a light field at different angles of incidence in the cavity of a fusion device after a flat-top Gaussian beam passes through a lens. This analysis focuses on the effect of angle of incidence of the beam on the light-intensity distribution at the focal point in the cavity. Simulation results show that as the angle of incidence of the beam increased, the light intensity of the spot at the focal point is affected in the X-axis direction, and the light spot diffused along the X-axis direction, but the light-intensity distribution in the Y-axis direction barely changed. As the transmission distance along the optical axis increased, the spot diameter in the cross section of the target cavity became larger, uniformity became worse, and spot position deviated to the right. Conclusively, the angle of incidence and distance of the beam transmission must be appropriately selected to obtain a light spot with good uniformity in the cavity.
苏倩倩, 汤梦饶. 平顶光束在间接驱动靶腔内的光强分布特性[J]. 激光与光电子学进展, 2020, 57(15): 151403. Qianqian Su, Mengrao Tang. Light-Intensity Distribution Characteristics of Flat-Topped Beam in Indirectly Driven Target Cavity[J]. Laser & Optoelectronics Progress, 2020, 57(15): 151403.