Home – Home – Jornals – Avtometriya 2026 number 1

A new method for improving the quality of images reconstructed from digital holograms is considered. It utilizes spatial subpixel shifts, i.e., shifts by a certain value smaller than the resolution provided by the recording devices. In digital holography, photodetector matrices are used as a recording medium for holograms. The resolution is determined by the type of matrices used. To obtain holograms, a camera with a photodetector matrix with a resolution of 9000 × 6752 and a single element size of 0.86 × 0.86 μm was used. The size of the matrix used was 7.7 × 5.8 mm, the spatial resolution of such devices is approximately 500-1000 lines/mm. This already makes it possible to obtain digital holograms. However, to improve the quality of reconstructed images, it is necessary to increase the hologram resolution during registration. To increase the resolution, a device for introducing a spatial subpixel shift of the photodetector matrix was used in this study. Insufficient matrix resolution was compensated for using subpixel spatial shifts. The shift was performed along the X and Y coordinates by 430 nm, which was half the size of one matrix element. The digital hologram size increased fourfold (18,000 x 13,504 pixels). Image reconstruction was performed using a fast Fourier transform. To speed up the process, a graphics accelerator was used to reconstruct images from holograms.