Article

Variable-radius focused optical vortex with suppressed sidelobes

University of Cambridge, Cambridge, England, United Kingdom
Optics Letters (Impact Factor: 3.18). 07/2006; 31(11):1600-2. DOI: 10.1364/OL.31.001600
Source: PubMed

ABSTRACT We propose a design for a phase mask for generating an optical vortex with suppressed sidelobes in the focal plane where the radius of the intensity ring is variable. A radial modulation added to conventional phase mask exp(iltheta) projects the light diffracted from different annular zones into a single intensity ring in the focal plane.

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