Spectral Modification by Diffraction and Scattering

M Taghi Tavassoly,Masoomeh Dashtdar,Mohammad Amiri

doi:10.1155/2010/613728

M Taghi Tavassoly, Masoomeh Dashtdar + Show 1 more

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https://doi.org/10.1155/2010/613728

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Abstract

Different effects induce spectral changes, for example, correlation of source fluctuations, propagation of light, random changes in optical properties of a medium, diffraction and scattering from objects, and rough interfaces. We review the spectral changes that occur as a result of light diffraction from phase steps, and particularly we discuss the spectral changes in the neighborhood of phase singularities. We also review the redshift and blueshift in the spectra of the lights coherently and diffusely scattered from rough interfaces. In addition, we study the effects of roughness and incident angle on the spectral profiles of scattered lights in reflection and transmission modes.

Highlights

After being realized in 1986 [1] that the spectrum of radiation may change on propagation, a considerable volume of works has been carried out dealing with spectral changes induced by the correlated fluctuations in sources and changes in coherence properties of radiations [2, 3]
Since the spatial coherence width of a light beam increases with the distance from the source, any light beam is coherent to some extent that depends on the source size and the distance from the source
As a coherent or partially coherent polychromatic beam of light passes through a medium that imposes different phases on different parts of the beam, the beam scatters from these parts and interference of the scattered lights leads to spectral changes

Summary

Introduction

After being realized in 1986 [1] that the spectrum of radiation may change on propagation, a considerable volume of works has been carried out dealing with spectral changes induced by the correlated fluctuations in sources and changes in coherence properties of radiations [2, 3]. Since the spatial coherence width of a light beam increases with the distance from the source, any light beam is coherent to some extent that depends on the source size and the distance from the source. As a coherent or partially coherent polychromatic beam of light passes through a medium that imposes different phases on different parts of the beam, the beam scatters from these parts and interference of the scattered lights leads to spectral changes. In this paper we study the spectral changes that occur as a result of light diffraction from phase steps and light scattering from rough interfaces in reflection and transmission modes

Modified Spectrum of Diffracted Light

Spectral Modification of the Light Scattered from Rough Interfaces

Conclusions