Near-field diffraction tomography with diffuse photon density waves

An angular spectrum algorithm is presented for fast, near-field diffraction tomographic imaging with diffuse photon density waves in highly scattering media. A general relation in K space is derived that connects the spatial variations of the optical properties of heterogeneities to the spatial spec tra of the measured scattered diffuse photon density waves. The theory is v erified experimentally for situations when boundary effects can be neglecte d. We further describe how to reconstruct absorption and scattering propert ies simultaneously, and how to incorporate boundary conditions into this an gular spectrum algorithm for a turbid medium of finite size (e.g., the slab medium). Limitations and potential improvements of the near-field diffract ion tomography are also discussed.