1.
Opt Lett
; 31(11): 1597-9, 2006 Jun 01.
Article
in English
| MEDLINE
| ID: mdl-16688232
ABSTRACT
We derive analytical expressions containing a hypergeometric function to describe the Fresnel and Fraunhofer diffraction of a plane wave of circular and ringlike cross section by a spiral phase plate (SPP) of an arbitrary integer order. Experimental diffraction patterns generated by an SPP fabricated in resist through direct e-beam writing are in good agreement with the theoretical intensity distribution.