On the basis of the stationary phase principle, we construct a family of shaping nondiffracting structured caustic beams with the desired morphology. First, the analytical formula of a nondiffracting astroid caustic is derived theoretically using the stationary phase method. Then, several types of typical desired caustics with different shapes are numerically simulated using the obtained formulas. Hence, the key optical structure and propagation characteristics of nondiffracting caustic beams are investigated. Finally, a designed phase plate and an axicon are used to generate the target light field. The experimental results confirm the theoretical prediction. Compared with the classical method, the introduced method for generating nondiffracting caustic beams is high in light-energy utilization; hence, it is expected to be applied conveniently to scientific experiments.

连续位相板(CPP)经过透镜聚焦后，在焦平面上形成一个散斑场，散斑场的统计性质决定了CPP的束匀滑特性。当使用大数值孔径透镜聚焦后，傍轴近似不再成立，因此分析CPP焦斑特性时标量衍射理论不再适用。采用Richard-Wolf矢量衍射理论对强聚焦条件下的CPP焦斑进行了计算，在此基础上分析了矢量焦斑场的统计特性，讨论了焦斑的轮廓。结果表明，由于非近轴的原因，矢量分析得到的焦斑尺寸略大，且通过矢量分析后能够得到z轴方向的光场分量。散斑场的振幅分布满足瑞利分布特性，强度分布满足负指数分布特性，且矢量合成方向的光强分布会略微偏离负指数分布特性。

传统的长焦深光束生成器件，诸如空间光调制器和正负透镜组合，存在光学元件尺寸较大、难以与微纳光学系统集成等问题，发展一种长焦深光束生成方法并制备一种结构简单、尺寸紧凑且成像质量良好的长焦深光束器件尤为重要。提出了一种利用连续立方相位板调制来产生长焦深光束的方法，通过飞秒激光直写技术制备了高尺寸精度（直径为108 μm，高1.1 μm）的相位板，实现了可调控的焦距长度（50~150 μm）和焦深（100~600 μm），并且对相位板进行光学测试，展示了其长聚焦能力和成像能力。该器件可用于高性能集成光学系统、微纳光学制造等领域。