推导出了正交光楔列阵(CSWA)聚焦系统的多光束干涉条纹主极大和两相邻主极大间的次极大间距公式,并根据广义惠更斯-菲涅耳衍射积分理论,通过数值计算证明了CSWA的小尺度不均匀性的变化规律与物理光学的公式符合。另外,提出改善小尺度不均匀性的两种方法:楔角偏差和离焦打靶技术。计算分析和实验研究表明,优化楔角偏差和离焦景的量值,即δpj=2.0%,△Z=2mm时,干涉主极大间隔与没加这两种技术时相比减小了6倍,小尺度的不均匀性得到了明显的改善。
The Separation of Interference Fringes of the Main Diffraction Maxima (SIFMDM) and the second maximum for Cross Segmented Wedge Array (CSWA) focus system were derived, and the change rules of the Small scale Irradiation Non-uniformity(SSINU) were confirmed by numerical calculations based on the generalized Huygens-Fresnel diffraction integral theory. The two methods of reducing the SSINU, the Deviation of Wedge Angles (DWA) and the Off-focal Laser Radiation on the Target (OFLRT),were proposed. Theoretical study and experimental results show they agree quite well. By both the DWA and the OFLRT, the SIFMDM can be reduced by 6 times and the SSINU is also improved obviously, when the DWAS and off-focal variables are optimized to δpj=2.0%,△Z=2mm.