It is quite difficult to determine the coordinates and magnification of reconstructed holographic image of a particle due to the lack of a clear geometrical-optical model describing the digital holographic process. To obtain magnified images in traditional optics and microscopy, lenses are usually used. In digital holography, such images can be formed without mechanical focusing and the use of optical components, for example, by controlling the divergence of illumination beams. This paper considers the issues related to the optimization of the optical scheme of digital holography that ensures lensless magnification of reconstructed images, justifies the feasibility of using a geometric optics apparatus in the design of such digital holographic systems, and describes their limitations. The results of the work can be used in the design and development of digital holographic microscopy systems, for high-precision reconstruction and analysis of holographic images of particles.
digital holography, lensless magnification, geometric-optical model, reconstructed image
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