Off-axis digital holographic wave-front recording and reconstruction method and implementation device

Abstract

The invention discloses an off-axis holographic wave-front recording and reconstruction method and an implementation device. In off-axis digital holography, if the spatial frequency of a reference wave is higher than that of an object wave, a differential sign of a relative phase of the object wave is kept unchanged; the non-integral reconstruction of off-axis digital holographic wave-front phase information is successfully realized by virtue of such a phase differentiation characteristic. According to the method, only the spatial frequency of the reference wave is required to be higher than that of the recorded object wave, so that the method can be applied to various off-axis holographic wave-front reconstruction comprising slightly-off-axis holography; meanwhile, integral operation such as Fourier transform involved in a conventional off-axis holographic technology is also avoided, so that the requirement on a memory of a data processing device can be greatly lowered, and the wave-front reconstruction efficiency can be improved; by virtue of such a characteristic, the method is particularly applied to the wave-front reconstruction of a large-sized off-axis digital hologram.

Description

technical field [0001] The invention relates to an off-axis digital holographic wavefront recording and reproducing method and implementation device. Background technique [0002] With the development of computer and digital image sensor technology, digital holography (DH) technology has been greatly developed in recent years, and has been successfully applied in the fields of contour measurement, digital microscopic imaging, image recognition, particle testing, and terahertz imaging. [0003] Based on the relative orientation of the object wave and the reference wave during the holographic recording process, digital holographic recording optical paths can generally be divided into two categories: on-axis holographic recording and off-axis holographic recording. [0004] In coaxial holography, the angle between the object wave and the reference wave is close to zero; theoretically, this recording method can make full use of the resolution of the image sensor used in holograp...

AI Technical Summary

Problems solved by technology

However, the wavefront reconstruction of the existing micro-off-axis holography technology mainly uses the integral algorithm (Fourier and Hilbert transform) or the phase shift algorithm, which has high requirements on the system hardware and a large amount of calculation.

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