Phase Aberrations in Bragg Imaging
Theoretical investigations of Bragg imaging in three dimensions show that a cylindrically convergent light beam reconstructs each plane wave component of the sound field unambiguously. However, aberrations in the image plane arise for those sound components that project out of the plane normal to the line formed by the light. Particularly it is shown that images from long objects oriented parallel to the convergence of the light beam are free from significant phase aberrations (i.e., the components at the image plane have essentially the same phase with respect to each other as the associated sound components). However, similar analysis and experiments show that images of objects oriented at right angles to this direction do indeed have a significant phase aberration.
KeywordsPlane Wave Sound Source Line Source Image Point Sound Field
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