Fresnel incoherent digital holography single exposure imaging method and system

Abstract

The invention provides a Fresnel incoherent digital holography single exposure imaging method and system. The method comprises the steps of loading a dual-lens mode onto a spatial light modulator; loading a phase mask having a phase shift angle of 0 degree onto the spatial light modulator; recording a 0-degree phase shift hologram by an image acquisition device; constructing a 120-degree phase shift hologram H2 and a 240-degree phase shift hologram H3 separately by using the 0-degree phase shift hologram H1, and superimposing the three phase shift holograms to obtain a complex-valued hologram H; and reproducing the complex-valued hologram in a computer by using angular spectrum diffraction. The method records the 0-degree hologram by loading the dual-lens phase mask on the spatial light modulator, constructs the 120-degree and 240-degree holograms by using the hologram, removes the interference of a zero-order image and a conjugate image by a three-step phase shift interference technique, and reconstructs the superimposed complex-valued hologram by the angular spectrum method to obtain a reconstructed image. The method realizes the common coaxial incoherent digital holography single exposure imaging, has the advantages of FINCH technology, and provides a powerful guarantee for real-time imaging of incoherent digital holography.

Description

technical field [0001] The invention belongs to the technical field of optical diffraction imaging and incoherent digital holography, and in particular relates to a Fresnel incoherent digital holographic single-exposure imaging method and system. Background technique [0002] In recent years, with the advancement of computers, high-resolution charge-coupled devices (CCDs) and spatial light modulators (SLMs), digital holography has developed rapidly. Limitations, play a unique advantage, the most striking technology is the SLM-based Fresnel Incoherent Correlation Holography (FINCH) proposed by Joseph Rosen et al. FINCH technology does not need to scan or move any optical devices during the recording process, and can quickly obtain the three-dimensional information of the object, realizing the incoherent digital holographic recording of the same path and coaxiality, which has strong stability and high resolution compared with traditional digital holographic imaging , Imaging ...

AI Technical Summary

Problems solved by technology

In 2018, Dong Liang et al. used a geometric phase lens instead of a spatial light modulator and combined it with a camera with a micro-polarizer array. Using parallel phase-shift digital holography technology, a hologram containing multiple phase-shift interference information can be obtained. Through The four-step phase-shift method obtains the composite hologram, and realizes the single-exposure recording of Fresnel incoherent coaxial digital holography. Although the optical path of this method is simple and compact, the reconstructed image quality of the obtained hologram is poor.

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