IMPACT OF PROXIMITY EFFECT ON RESOLUTION IN IMAGES RECONSTRUCTED BY COMPUTER-GENERATED HOLOGRAMS

Subject of Research. The paper presents research results on the impact of the optical proximity effect, well-known in traditional photolithography, on the quality of images reconstructed using computer-generated phase modulated Fresnel holograms. Method. The study was carried out through mathematical modeling of real physical processes of synthesis and reconstruction of holograms of various structure binary transparencies in the virtual space. Each of the transparencies was examined in two versions: in the first one, it was illuminated in phase, and in the second one, the radiation incident on its neighboring elements was out of phase. Further, quality comparison of the reconstructed images was carried out. A criterion for the quality estimation of reconstructed image was expressed in terms of a number of gradations in the threshold processing of this image, in which the intensity distribution in the reconstructed image would be identical to the intensity distribution in the original object. Main Results. It is established that at image reconstruction by computer-generated holograms, the method of phase compensation of proximity effect has a positive impact on the resolution in the reconstructed image. The proximity effect manifests itself most clearly when the distances between the elements of the transparency objects do not exceed one pixel, regardless of the pixel size itself and the structure of the photomask object used. Practical Relevance. We give recommendations on the practical application of the proximity effect compensation method for improving the quality of images obtained by the holographic photolithography method.

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