Computations of the acoustically induced phase shifts of optical paths in acoustophotonic imaging with photorefractive-based detection.

Acoustophotonic imaging uses ultrasound-modulated scattered light to improve the quality of optical imaging in diffusive media. Experiments that use photorefractive-crystal-based detection have shown that there is a large dc shift in the acoustically modulated or ac optical signal, which could be utilized to further improve optical imaging resolution. We report that photon paths in a diffusive medium were generated by a Monte Carlo simulation, and the optical phase shifts of the various photons induced by the presence of a realistic focused ultrasound beam were calculated.

Leaky helical flexural wave backscattering contributions from tilted water-filled cylindrical shells.

Helical flexural waves on a bluntly truncated tilted water-filled cylindrical steel shell in water are found to give large contributions to the backscattering above the coincidence frequency. The presence of the water inside the shell increases the damping of the leaky wave when short tone bursts are used. The magnitude of the scattering is found by modifying a ray analysis developed for empty shells.

Leaky helical flexural wave backscattering contributions from tilted cylindrical shells in water: observations and modeling.

For tilt angles smaller than the meridional ray coupling condition previously investigated [S. F. Morse et al.