1. An imaging system comprising: a surgical microscope comprising at least one objective lens; a projection device attached to a port of the microscope, the projection device configured to project spatially modulated light in a selected predetermined pattern through the at least one objective lens and onto tissue; a camera configured to record an image of the tissue as illuminated by the spatially modulated light; an image processor having a memory with a routine for performing spatial Fourier analysis on the image of the tissue to recover spatial frequencies; the image processor further comprising a routine for constructing a three dimensional model of the tissue, and a routine performing fitting of at least absorbance and scattering parameters of voxels of the model to match the recovered spatial frequencies; and apparatus for displaying tomographic slices of the three dimensional model.