A general n-fractal aperiodic zone plate

ABSTRACT

We propose a general n-fractal aperiodic zone plate generating a beam with the first-order foci with more chosen positions. The construction method of the general n-fractal aperiodic zone plate can apply to many aperiodic zone plates, e.g. fractal, Thue-Morse and Fibonacci zone plates, and the general n-fractal aperiodic zone plates can generate more adjustable first-order foci. Parameters of the n-fractal aperiodic zone plate such as the substitution rule and the fractal order are examined and found not to affect the fractal distribution of the first-order foci. The more adjustable first-order foci generated by the general n-fractal aperiodic zone plate have been verified with both simulations and experiments.

KEYWORDS:

• General n-fractal aperiodic zone plate
• adjustable first-order foci
• substitution rule
• fractal order

Acknowledgement

This work is supported by the National Natural Science Foundation of China [grant number 11674401], [grant number 11747105], and the Natural Science Foundation of Hunan Province, China [grant number 2019JJ40358].

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work is supported by the National Natural Science Foundation of China [grant number 11674401], [grant number 11747105], and the Natural Science Foundation of Hunan Province, China [grant number 2019JJ40358].