Single slit diffraction: From optics to elasticity

•Results of simulations of plane wave propagation through a single slit are presented.•Classical optical, acoustic, and elastic cases are compared.•Elastic case differs from optical and acoustic ones.•The variation of material parameters changes the stress distribution drastically.•The observed difference between acoustic and elastic cases is unavoidable.

The comparison of numerical simulations of the classical problem of the single slit diffraction in optical, acoustic, and elastic cases is presented in the paper in the plane strain setting. It is shown that wave fields downstream the slit are similar in optical and acoustic cases, as expected. Corresponding wave fields in the single slit diffraction using elastic materials become essentially different from optical and acoustic cases. This is an effect of elastic waves propagating inside the plate forming the slit.