Analysis of DOEs in the Fresnel Diffraction Regimes

doi:10.1117/3.2261461.ch4

Book: Design and Fabrication of Diffractive Optical Elements with MATLAB

Author(s): Anand Vijayakumar, Shanti Bhattacharya

Published: 2017

https://doi.org/10.1117/3.2261461.ch4

Author Affiliations +

Abstract

In earlier chapters, the design of DOEs and the simulation of their far-field diffraction patterns using Fraunhofer diffraction formula were presented. However, to characterize a DOE, it is necessary to analyze phase and intensity profiles at different propagation distances. For instance, the binary axicon or circular grating generates a ring-like pattern in its far field, and it generates a Bessel-like beam closer to the element. With its large focal length, the Bessellike beam, is used for many applications. Hence, it is necessary to simulate and understand the field variations at several planes of interest. In this chapter, a MATLAB simulation of diffraction patterns in the Fresnel regime is presented. The analysis and simulation presented here are not suitable for planes very close to the DOE.