Accuracy of determination of longitudinal coordinates of particles by digital holography
V.V. Dyomin, A.Yu. Davydova, I.G. Polovtsev, N.N. Yudin, M.M. Zinoviev
National Research Tomsk State University, Tomsk, Russia
Keywords: digital particle holography, reconstructed particle images, longitudinal coordinates of particles, error, diffraction-limited systems
Abstract
Based on known expressions applied to diffraction-limited optical systems, estimates are given and a method is proposed for determining the measurement error of the longitudinal coordinates of particles from images reconstructed from digital holograms. A correction factor for visual focusing is determined for different distances between a detected particle and the plane of a CMOS matrix. The experimental results of testing the method are presented. It is shown that the error of automatic digital focusing can be reduced by simultaneously applying focusing curves for several quality indicators and optimizing the image area for their construction.
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