Hologram aberrations resulting from the violation of Bragg's law and variations in the depth and shape of the profile of their surface gratings

摘要

Hologram aberrations resulting from the violation of Bragg's law and variations in the depth and shape of the profile of their surface gratings are investigated. This study is conducted for specific cases of reflecting relief-phase holograms and lossless transmitting volume holograms. The commonly used and previously published assumption that the imaging properties of the hologram, including its aberrations, are fully determined by the pattern of the strata exposure on the hologram surface was shown to be generally true for reflecting relief-phase holograms and only partially true for transmitting volume holograms. For the latter, the deviations from Bragg's law both in incidence angle and wavelength of the reconstructing beam can lead to significant aberrations in the ray beams transformed by the holographic optical elements. This study unambiguously demonstrates that the modules for calculating the aberrations caused by the deviations from Bragg's law should be added to the software used to design optical systems with volume holographic optical elements. (C) 2021 Optica Publishing Group