<title>Ultrasound light diffraction</title>

Abstract

ABSTRACTLight diffraction by ultrasound waves is discussed in the wide range from weak acousto-opticinteraction to strong acousto-optic interaction in terms of numerical simulations and experimental investigations for normal incidence. Particular emphasis has been placed on the complex nature of thediffracted light amplitude. The paper is intended as a contribution towards a unified representation ofthe general phenomenon.1 . INTRODUCTIONDuring the 60 year-history of research activities in the field of ultrasound light diffraction, interesthas mainly been concentrated on the investigation of the light intensity in various diffraction orders andin the optical near field. It seems, however, that more attention should be paid to the diffracted light amplitude, since its complex nature provides additional information which contributes to a unified representation of the phenomenon.In this paper, starting from the Raman-Nath system of difference differential equations, we discussthe complex nature of the diffracted light amplitude making use of selected examples. We then present