Square Fresnel zone plate with spiral phase for generating zero axial irradiance
1Department of Physics, Zhejiang University, Hangzhou 310027, China.
Optics Letters
|May 4, 2010
Abstract:
A type of square Fresnel zone plate with spiral phase for generating zero axial irradiance is proposed. Diffraction patterns of the zone plates with different generalized topological charges are given by numerical simulation, which also suggests their potential applications in generating hollow beams.
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