Optical simulation of bistatic specular reflection by a rigid cone on a flat surface.

To gain insight into the high‐frequency scattering of sound by cone‐shaped objects near flat reflecting surfaces, a small conical mirror was placed on a flat horizontal mirror and illuminated by a tilted laser beam. The symmetry axis of the cone was vertical. Light scattering patterns were recorded by imaging with a camera on a white vertical screen that intersected the scattering. Bright regions on the screen were associated with specular reflections from the cone and from the flat mirror. To determine which contributions depended on the presence of the flat mirror, the screen was also imaged with the cone on a nonreflecting surface. The patterns were recorded with the screen placed sideways relative to the laser beam as well as in front of the cone and behind the cone. The cone half‐angle was 45 deg but the grazing angle of the laser beam could be changed. The bright patterns were described by a geometric analysis of bistatic reflection previously summarized [P. Marston, J. Acoust. Soc. Am. 124, 2584 (2...