A review of recent work in which persistent spectral holes have been burnt as laser induced gratings (plane wave holograms) in the inhomogeneously broadened absorption bands of dye doped polymers is presented. The holographic detection technique is compared to the transmission technique and it is shown that a comparison of transmission and holographic hole widths leads to a direct measurement of homogeneous linewidth. Interference between spectrally adjacent gratings is dependent on the relative phase selected during burning. This consideration is important in the analysis of interference between spectrally adjacent gratings which are split through the application of an external electric field. Finally, the influence of the reconstruction symmetry is described.
