Precision and bias in dynamic light scattering optical coherence tomography measurements of diffusion and flow

We quantify the precision and bias of dynamic light scattering optical coherence tomography (DLS-OCT) measurements of the diffusion coefficient and flow speed for first and second-order normalized autocovariance functions. For both diffusion and flow, the measurement precision and accuracy are severely limited by correlations between the...

Scanning dynamic light scattering optical coherence tomography for measurement of high omnidirectional flow velocities

We show scanning dynamic light scattering optical coherence tomography (OCT) omnidirectional flow measurements. Our method improves the velocity measurement limit over conventional correlation-based or phase-resolved Doppler OCT by more than a factor of 2. Our technique is applicable without a-priori knowledge of the flow geometry as our...

Sub-diffusion flow velocimetry with number fluctuation optical coherence tomography

We show number fluctuations dynamic light scattering optical coherence tomography (OCT) for measuring extremely slow, sub-diffusion flows of dilute particle suspensions. Our method removes the minimum measurable velocity limitation of conventional correlation-based or phase-resolved Doppler OCT, set by flowing particles’ Brownian motion. Our...

Sub-diffusion flow velocimetry with number fluctuation optical coherence tomography

We have implemented number fluctuation dynamic light scattering optical coherence tomography (OCT) for measuring extremely slow, sub-diffusion flows of dilute particle suspensions using the second-order autocovariance function. Our method has a lower minimum measurable velocity than conventional correlation-based OCT or phase-resolved Doppler...

Sub-diffusion flow velocimetry with number fluctuation optical coherence tomography

We show number fluctuations dynamic light scattering optical coherence tomography (OCT) for measuring extremely slow, sub-diffusion flows of dilute particle suspensions. Our method removes the minimum measurable velocity limitation of conventional correlation-based or phase-resolved Doppler OCT, set by flowing particles’ Brownian motion. Our...

Scanning dynamic light scattering optical coherence tomography for measurement of high omnidirectional flow velocities

We show scanning dynamic light scattering optical coherence tomography (OCT) omnidirectional flow measurements. Our method improves the velocity measurement limit over conventional correlation-based or phase-resolved Doppler OCT by more than a factor of 2. Our technique is applicable without a-priori knowledge of the flow geometry as our...

Development and Validation of an End-to-End Simulator for Frequency Scanning Filtered Rayleigh Scattering Techniques

An end-to-end simulator for frequency scanning methods of filtered Rayleigh scattering (FSM-FRS) has been developed during the master thesis research at the German Aerospace Center (DLR). It can model several frequency scanning filtered Rayleigh scattering methods and predict the accuracies in measuring flow temperature, pressure, and velocity....