Three-dimensional beam-deflection optical tomography of a supersonic jet

Abstract

We report 3-D imaging of density in a supersonic expansion using beam-deflection optical tomography. Quantitative high-resolution images with absolute accuracy of 3%, dynamic range of 500:1, and spatial resolution to within a factor of 1.7 of the diffraction limit were produced with a He–Ne laser and simple apparatus. Theory shows that the spatial frequency content of beam-deflection measurements is well suited for tomographic reconstruction. The theory for the diffraction-limited resolution for tomography is presented.