Open AccessGeneration of high-order optical vortices with asymmetrical pinhole plates under plane wave illumination
Author(s) -
Zhenhua Li,
Meina Zhang,
Guangxin Liang,
Xing Li,
Xiaoyi Chen,
Chuanfu Cheng
Publication year - 2013
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.21.015755
Subject(s) - optics , physics , optical vortex , pinhole (optics) , vortex , zone plate , diffraction , fresnel diffraction , wavelength , fresnel number , fresnel zone , azimuth , plane (geometry) , interferometry , ptychography , geometry , beam (structure) , mathematics , thermodynamics
We propose a novel and simple method for generating optical vortex with high topological charge (TC), merely using an asymmetrical pinhole plate illuminated by plane wave. N pinholes are arranged along a particular spiral line around the plate origin, with constant azimuth angle increment and varied radial distances. The radial differences introduce a constant variation of m/N wavelength to the optical paths from the N pinholes to the observation plane origin, and this increases the phases of the transmitting waves by progressively 2mπ/Nand totally 2mπ. We numerically calculate the transmitted light field according to the Fresnel diffraction theory, and find the vortex with TC m around the observation plane origin. The experimental verifications are performed using some self-made asymmetrical pinhole plates fabricated by a femtosecond laser, with the high TC vortices both generated and detected in a Mach-Zehnder type interferometer. The experimental results coincide with the theoretical simulations well.