Method for realizing large-phase reconstruction of single digital hologram by adopting intensity transmission equation

Abstract

The invention relates to a method for realizing large-phase reconstruction of a single digital hologram by adopting an intensity transmission equation. The method comprises the steps of building a single-beam or dual-beam plane wave hologram recording system, taking d as the recording distance, and acquiring a digital hologram containing intensity and phase information of a measured objected; realizing numerical reconstruction of the digital hologram by respectively using three different reconstruction distances (d'-deltad), d' and (d'+deltad), and acquiring intensity images of the measured object on three planes; taking the three intensity images as a data source, substituting the three intensity images into the intensity transmission equation, solving the intensity transmission equation by using a Green function model, and acquiring phase distribution of the measured object on an imaging plane. According to the invention, phase reconstruction in the single hologram is realized by using the intensity transmission equation, and a step of unwrapping in the traditional holographic phase reconstruction process is avoided, thereby being not restricted by the depth of traditional holographic phase reconstruction, and thus being capable of realizing large-phase reconstruction.

Description

technical field [0001] The invention relates to a large phase reconstruction method, in particular to a large phase reconstruction method for a single digital hologram by using an intensity transmission equation. Background technique [0002] Digital holography technology, as an optical non-destructive testing technology with rapidity, globality and digital focusing function, is a very effective microscopic quantitative detection method, but the disadvantage is that the traditional reconstruction algorithm is essentially based on the plane diffraction theory. What is obtained is the wrapping phase, and the unwrapping algorithm is usually very complicated and needs to compensate for the error, and the reconstructed phase corresponding to the measured axial depth is only in the micron range. [0003] The intensity transfer equation phase reconstruction technique is a non-interference quantitative phase recovery method gradually formed on the basis of the imaginary solution of ...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for realizing large phase reconstruction of a single digital hologram by using the intensity transfer equation to solve the shortcomings of the existing phase reconstruction technology. The main advantage of this method is to overcome the depth of phase reconstruction in digital holography technology. It is limited to the micron range and the phase needs to be unwrapped. It also simplifies the data acquisition method of the traditional phase reconstruction measurement process, reduces the amount of collected data, and reduces the amount of introduced errors.

After the intensity information reconstruction is completed, the three intensity reconstruction maps are substituted into the intensity transfer equation as input data to complete the phase reconstruction

Images