The memorandum [Optica 7, 252 (2020). [CrossRef] ; Optica 7, 1323 (2020). [CrossRef] ] is devoted to the design, fabrication, and characterization of an optimized multi-level diffractive lens, emphasizing the advantages of the multi-level approach compared to the metalens approach. While such advantages may well exist, we feel that a number of statements in the memorandum require clarification. We add some references on multi-level diffractive lens optimization that place the memorandum’s contributions in a more complete context.

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通过逆向设计的大面积、高数值孔径多级衍射透镜：评论

备忘录 [Optica 7 , 252 (2020)。[交叉引用] ; 光学7 , 1323 (2020)。[CrossRef] 致力于优化多级衍射透镜的设计、制造和表征，强调多级方法与元透镜方法相比的优势。虽然这些优势很可能存在，但我们认为备忘录中的一些声明需要澄清。我们添加了一些关于多级衍射透镜优化的参考，将备忘录的贡献置于更完整的上下文中。