A diffraction coherence filter based on Bragg interference principles comprises a plurality of spaced-apart lower-hierarchy optical elements, containing a series of interference structures, which form a higher-hierarchy compound optical structure. The spatial distribution of the lower-hierarchy optical element and the interference structures is governed by mathematical relationships dependent upon the coherence radius and temporal coherence length of incoming radiation. All of the lower-hierarchy elements can be coherently coupled for coherent light and randomly coupled for incoherent light, whereby the filter may differentiate between coherent and incoherent radiation.