正交偏振板对聚焦光斑偏振特性的影响

在间接驱动的惯性约束聚变(ICF)驱动器中,为控制靶腔入口及其附近光场的偏振特性及辐照均匀性,采用二维光谱角色散(2D-SSD)、随机相位板(RPP)和正交偏振板(OPCP)联用的束匀滑方案,数值模拟和理论分析了OPCP对焦面及离焦面处光场偏振特性以及强度均匀性的影响,并讨论了正交偏振板单元数的选取问题。结果表明,不同单元数正交偏振板对焦面及其附近光场偏振特性和强度均匀性的影响程度不同,且光场偏振特性对离焦并不敏感。此外,离焦会使强度均匀性变差,适当增加正交偏振板单元数可以在一定程度上减弱这种影响。

Effect of orthogonal polarization control plate on polarization property of focus speckle

For the control of the polarization property and intensity uniformity of optical field near the entrance of the target chamber in indirect drive Inertial Confinement Fusion (ICF), two-dimensional spectral angular dispersion (2-D SSD), random phase plate (RPP), combined with orthogonal polarization control plate (OPCP) have been employed. Influence on the polarization property and intensity uniformity in and near the focal plane by using OPCP has been numerically simulated and theoretically analyzed, and the choice of the number of elements of OPCP has been discussed. The results show that OPCP with different number of elements exhibits different extent of influence on the polarization property and intensity uniformity of optical field in and near the focal plane, and that the polarization property of optical field is not sensitive to defocus. In addition, defocus will degrade the intensity uniformity more or less, but the effect would be reduced by appropriately increasing the number of elements of OPCP.