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6 - Transformation of optical fields by structured surfaces

Published online by Cambridge University Press:  01 June 2011

A. A. Maradudin
Affiliation:
University of California, Irvine, CA 92697 USA
E. R. Méndez
Affiliation:
División de Física Aplicada, Centro de Investigación Científica y de Educación Superior de Ensenada, Carretera Ensenada-Tijuana No. 3918, Ensenada, B. C., 22860, México
T. A. Leskova
Affiliation:
University of California, Irvine, CA 92697 USA
Alexei A. Maradudin
Affiliation:
University of California, Irvine
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Summary

Introduction

A reader of this book will quickly see that structured surfaces, whether deterministic or random, can reflect, transmit, refract, and amplify volume or surface electromagnetic waves in ways that naturally occurring surfaces cannot. They can also change the nature of an electromagnetic field incident on them. For example, they can change a beam with one intensity distribution into a beam with a different intensity distribution, or they can convert a plane wave into a beam. The use of structured surfaces, specifically randomly rough surfaces, to effect such transformations of optical fields is the subject of this chapter, where two examples of this use are presented, namely beam shaping and the formation of pseudo-nondiffracting beams.

The creation of optical elements that transform an electromagnetic beam with a specified transverse intensity distribution into a beam with a different specified transverse intensity distribution, especially those that transform a laser beam with a Gaussian intensity profile into a beam with a constant intensity profile – a flat top beam, has been studied theoretically and experimentally for many years [1–38]. The interest in beam shaping is due to a wide range of applications for beams with a variety of non-Gaussian intensity distributions. These applications include laser surgery [39], laser radar [40], laser microstructuring of materials [41], metal hardening [42], optical communication [43], and optical scanning [44], among others. Some of them and other applications of beam shaping are discussed in the recent book by Dickey et al. [45].

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Publisher: Cambridge University Press
Print publication year: 2011

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