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Acousto-optics

A. Korpel, D.J. Mehrl, H.H. Lin, and W.J. Bridge

During the past half century, the problem of strong two-dimensional acousto-optic interaction has been attacked by a variety of analytic and numerical methods. The model most frequently used is one in which a rectangular, non-spreading sound column is illuminated by a single plane wave of coherent light. The analysis then proceeds along the classical lines of wave propagation in periodic media. When framed in terms of the coupled modes of the unperturbed medium, this leads to an infinite set of coupled equations—the well known Raman-Nath equations. Using the eigenmodes of the perturbed medium results in Mathieu functions.