Tomographic reconstruction of sound fields in air using TV-holography

A vibrating sound source causes periodic pressure variations in the air. The pressure variations lead to corresponding variations in the refractive index of the air which can be measured using full field interferometric techniques like TV-holography. Each measurement maps a cross-section of the integrated sound fields. To obtain a complete map of the volume distribution of sound field, we record cross-sections from different directions. Using tomographical backprojection of these recordings, we reconstruct the amplitude and phase of the sound field in any plane of the volume.