Visualization of the defects of a separate component of a composite diffractive optical element

The possibility of the visualization of the defects of a separate component of the thin composite diffractive optical element has been demonstrated. This element represents a thin substrate composition and a pair of combined elementary gratings. Possible variants of the defects visualization as the substrate and of the separate elementary gratings of the diffraction optical element have been considered. Interference methods well developed in holographic interferometry of phase objects have been used. Experimental results have been presented.