(a), (d) -real field in the plane of the screen. Theoretical calculation of the image (3) obtained from the diffraction of a plane wave on a metal screen with a hole in the form of a triangle (b-c) and a star (e-f). The image is calculated in planes z = z1, z = z1 ± λ. Let us note in more detail the conditions under which this effect is observed in the presented theory. Firstly, the construction of the image must occur in coherent light, i.e. the radius of coherence of radiation incident on the screen must be of the order of the size of the structure. Secondly, the distance from the center to the edge of the structure must be comparable to the PSF size of the optical system. In the examples we have considered, the sizes of the PSF are of the order of λ, therefore, the structures themselves have the same size. Thirdly, the distribution of the electromagnetic field in the plane of the object should be close to uniform. The structures must have a certain symmetry, in which the interference of the image from the center and edges of the figure leads to inversion in planes other than the focal one. It should be noted that the mirrored images is observed in a limited range of planes near the focus, see A similar effect was noted when calculating the virtual image in a spherical particle [5]. However, due to the reasons stated above, the effect was not observed in works considering such structures [6, 7]. We have considered the image of the created idealized optical system, described by formulas (1-3). In practice, the image is constructed using lenses. Does this effect occur in the case of real lenses? We designed a Fresnel lens placed on a gold screen with a triangle or star shaped hole in it. The position of the lens was determined in such a way that the screen with holes was located in its focal plane. The system forms an image in a transmission scheme. A plane wave with a wavelength of 1.2 µm is selected as the field source. The material chosen for the Fresnel lens is photopolymer ORMOSIL (SZ2080), the refractive index at this wavelength is n=1.454+0.013i [8]. The fields were read using monitors located in the focal area, the results are presented in Fig. 3. In the area of the geometric focus of the lens, an inverted image of the object can be observed (which is consistent with

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... field in the plane of the object should be close to uniform. The structures must have a certain symmetry, in which the interference of the image from the center and edges of the figure leads to inversion in planes other than the focal one. It should be noted that the mirrored images is observed in a limited range of planes near the focus, see Fig. 1. A similar effect was noted when calculating the virtual image in a spherical particle [5]. However, due to the reasons stated above, the effect was not observed in works considering such structures ...