为了提高激光微加工质量，对激光焦斑进行整形，采用菲涅尔衍射公式进行了理论分析，基于遗传算法和设计约束条件通过M atlab设计了两种二元相位元件，0-π结构四环相位板的归一化半径尺寸 r1＝0．15、r2＝0．70、r3＝0．81，非0-π结构四环相位板的归一化半径尺寸为r1＝0．25、r2＝0．498、r3＝0．652，从内到外各环对应的相位为2．879、3．087、0、3．012，采用这两种位相板调制后的纵向光斑大小可压缩至艾丽斑的76％和75％，峰值能量比分别为0．39和0．42，旁瓣能量分别为0．64和0．41，这两种相位板均可应用于飞秒激光微加工。%In order to improve the quality of laser micromachining , the focal spot should be shaped .The Fresnel diffraction formula was analyzed ,two kinds of axial super-resolved phase plates were designed by using Matlab based on genetic algorithms and design constraints .The normalized radiuses of 0-π structure phase plate of four-ring are r1 =0 .15、r2 =0 .70、r3 =0 .81 , and the normalized radiuses of non-0-π structure phase plate of four-ring are r1 =0 .25、r2 =0 .498、r3 =0 .652 ,the phases of each ring from the inside to the outside are 2 .879、3 .087、0、3 .012 . The longitudinal spot sizes after using the two phase plates are compressible to 76% and 75%of the Airy pattern ,the ratios of the peak energy are respectively 0 .39 and 0 .42 ,and sidelobe energy are respectively 0 .64 and 0 .41 .Two phase plates can be applied in femtosecond laser microfabrication .
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