Further investigation on the phase stitching and system errors in digital holography

Abstract

In this work, an improved phase stitching algorithm is proposed in digital holography (DH) based on a deduced phase errors model and a global optimization algorithm. In addition, to correct the relative rotation error between the coordinate systems of a CCD and xy-motion stages, we presented a simple and reliable image-based correction method. The experimental results obtained from our proposed method are compared with those calculated from the existing phase stitching method to verify the performance of the presented method. It is shown that our new proposed methods are robust and valid for measurement of a large microstructure element. As far as we know, the improved phase stitching algorithm and image-base correction method have not been discussed in DH, as we presented in this paper.

Investigation of the Space-Variance Effect in Digital Holography

“…14, which may result from phase aberration. The experimental results in [35][36][37][38][39][40][41] indicate that in digital holographic phase measurement, it is difficult to perfectly control or eliminate the phase aberration in the whole field of view. However, the "phase increase" in Fig.…”

Three-dimensional imaging of microstructures by an improved compact digital holographic microscope (ICDHM) with dual wavelength

“…Here real image term is selected with a numerical band filter and then it can be numerical reconstructed by the angular spectrum formulation [5]: where F and 1 F − denote Fourier transform and inverse Fourier transform operation, i U is the reconstructed complex amplitude of the object wavelength and i d is the reconstruction distance for i λ . For the reflection sample, the phase Φ of sample for the beat wavelength Λ can be written as…”

“…Microelectromechanical systems (MEMS), are highly demanding and a challenging task. For this reason, a compact handheld digital holographic microscope (CDHM) system is developed by A. Asundi et al [4,5], applications in micro-technology, MEMS inspection and semiconductor surface imaging. Recently, we presented an integrated lensless compact DHM system with a shorter laser wavelength to enhance the system resolution [6].…”

Quantitative phase image stitching guided by reconstructed intensity images in one-shot double field of view multiplexed digital holographic microscopy

“…However, alignment errors between the overlap sub-apertures may lead to phase stitching failure, which is less robust in real measurements. Wen et al established a mathematical model of the DH phase error and corrected the relative rotation error between CCD coordinate system and two-dimensional (2D) motion stage [ 10 ], but could not fully compensate for the stitching error caused by axial misalignment between the overlap sub-apertures. Xie et al integrated multiple algorithms such as phase correlation, Harris corner detection, and full matching search into the DH phase stitching to improve the stitching efficiency [ 11 ].…”