Quantitative dynamic evolution of physiological parameters of RBC by highly stable digital holographic microscopy

The coherent noise always exists in digital holographic microscopy due to the laser source, degrading the image quality. A method of speckle suppression using the dynamic speckle illumination, produced by double-moving diffusers, is presented in digital holographic microscopy. The space–time correlation functions are theoretically analyzed from the statistics distribution in the doubly and singly scattered system, respectively. The configuration of double-moving diffusers is demonstrated to have better performance in speckle suppression compared with the single diffuser and moving-static double diffusers cases. The experiment results verify the feasibility of the approach. The presented approach only requires a single shot interferogram to realize the speckle reduction, accordingly it has the potential application in real-time measurement.

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Volumetric monitoring of airborne particulate matter concentration using smartphone-based digital holographic microscopy and deep learning

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2021.126351 ◽

2021 ◽

pp. 126351

Author(s):

Jihwan Kim ◽

Taesik Go ◽

Sang Joon Lee

Keyword(s):

Deep Learning ◽

Particulate Matter ◽

Airborne Particulate Matter ◽

Digital Holographic Microscopy ◽

Airborne Particulate ◽

Particulate Matter Concentration ◽

Holographic Microscopy ◽

Matter Concentration

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3D monitoring of the surface slippage effect on micro-particle sedimentation by digital holographic microscopy

Scientific Reports ◽

10.1038/s41598-021-92498-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Majid Panahi ◽

Ramin Jamali ◽

Vahideh Farzam Rad ◽

Mojtaba Khorasani ◽

Ahamd Darudi ◽

...

Keyword(s):

Slip Length ◽

Particle Interaction ◽

Three Dimensional ◽

Digital Holographic Microscopy ◽

Particle Sedimentation ◽

Micro Particles ◽

Slippage Effect ◽

Holographic Microscopy ◽

3D Information ◽

Experimental Findings

AbstractIn several phenomena in biology and industry, it is required to understand the comprehensive behavior of sedimenting micro-particles in fluids. Here, we use the numerical refocusing feature of digital holographic microscopy (DHM) to investigate the slippage effect on micro-particle sedimentation near a flat wall. DHM provides quantitative phase contrast and three-dimensional (3D) imaging in arbitrary time scales, which suggests it as an elegant approach to investigate various phenomena, including dynamic behavior of colloids. 3D information is obtained by post-processing of the recorded digital holograms. Through analysis of 3D trajectories and velocities of multiple sedimenting micro-particles, we show that proximity to flat walls of higher slip lengths causes faster sedimentation. The effect depends on the ratio of the particle size to (1) the slip length and (2) its distance to the wall. We corroborate our experimental findings by a theoretical model which considers both the proximity and the particle interaction to a wall of different hydrophobicity in the hydrodynamic forces.

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