In analytical form, the peculiarities of forming Fraunhofer diffraction patterns and images of faces of a volumetric asymmetric edge of an object with an absolutely reflective internal surface in relation to dimensional inspection were investigated. Formulas were obtained for calculating fields in diffraction-limited systems depending on the magnitude of the bevel of the object c , the phase shift j of the wave reflected from the inner surface of the object, and the angular aperture of the

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... ent optical system for forming and filtering images. It has been established that for metal 3D-objects (j = p), the value of the field in the image of the back face at a point, corresponding to the position of its border is negligible with the depth of focus of the system much less than the thickness of the object. It is shown that when bevels of an object, much less than the size of the Fresnel zone d ~ ( l - wavelength of light, d - thickness of the object) and more than the depth of focus, the displacement of the intensity profile in the image of the front face is proportional and depends on the angle j. With large bevels, when and, the displacement of the front face boundary is inversely proportional to the value. These displacements can lead to systematic errors in measuring the position of the boundaries of the faces of a 3D-object and should be taken into account in precision dimensional inspection.