High-resolution digital holographic diffraction tomography

Abstract

Provided is high-resolution digital holographic diffraction tomography, belonging to the field of digital holography and diffraction tomography. A digital holographic diffraction tomography device isused for obtaining N synthetic high-resolution holograms by utilizing a synthetic aperture method, and then the high-resolution three-dimensional refractive index reproduction of a tested sample is obtained. In order to improve the imaging resolution of the system, the synthetic aperture method is introduced into a digital holographic diffraction tomography system, a two-dimensional electric translation platform is used for moving the CCD, the high-frequency information around the original hologram is acquired, and m*m (m>=3) sub-holograms are recorded when the angle of a galvanometer is theta), the m*m sub-holograms are subjected to intensity registration and image dislocation sub-pixel micro-displacement, so that a synthetic high-resolution hologram is obtained. The high-resolution three-dimensional imaging is realized by combining a digital holographic diffraction tomography method and the synthetic aperture method. The digital holographic diffraction tomography system can realize non-contact, non-marking, lossless and three-dimensional tomography measurement.

Description

Technical field [0001] The invention belongs to the field of digital holography technology and diffraction tomography, and relates to a high-resolution digital holographic diffraction tomography method, which can realize high-resolution three-dimensional tomography of an object. Background technique [0002] Digital holographic diffraction tomography is a kind of optical diffraction tomography technology, which is a fusion of digital holography and diffraction tomography. Its three-dimensional reconstruction is composed of the following two steps: 1) The process of recording and reproducing digital holograms. That is, first record the hologram of the measured object in multiple directions by digital holography, and then use spectral filtering and other methods to reproduce it numerically. 2) The three-dimensional reconstruction process is performed using diffraction tomography algorithm. The data obtained by digital holographic reconstruction is used as the source data, and the...

AI Technical Summary

Problems solved by technology

However, limited by the size of the CCD target surface, when recording a hologram on the recording surface, the area occupied by the interference fringes of the object light and reference light is often larger...

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