Abstract. We exploit the properties of the Dirac comb function to develop a pictorially appealing analysis of the relationship between the one-dimensional (1-D) spectrum of a signal waveform and the two-dimensional (2-D) spatial frequency spectrum of its raster record (generally referred to as the folded spectrum). Variations are considered, including the effects of recording with redundancy and of recording without appropriate "fall" of the raster lines. The use of the falling raster in time-integration folded spectrum analysis is analyzed, first from the stand-point of an important analogy with incoherent holography, then in terms of local oscillator arrays and moving comb functions. Finally, we consider the application of the falling raster to image processing.