Optical film thickness measurements using a reflectance mode swept-field confocal microscope
Document Type
Conference Proceeding
Publication Date
12-1-2011
Abstract
Multiphase flow in microchannels is frequently encountered in microdevices. Predicting the behavior of the multiphase flow has been difficult. The dynamics of liquid films inside of capillaries is important to microfluidic flows. At high flow rates with gas-liquid flows, the dynamics of liquid films on the interior surfaces of the microchannels can have a global affect on device operation. Measurement via optical microscopy of velocities in these liquid films and interface dynamics has been hampered by the inability to correctly image near dyanamic interfaces due to optical reflection and very short time scales of the flow. A novel technique for optically measuring liquid film thicknesses within circular microchannels has been developed. A swept-field confocal microscopy unit has been modified to capture the reflected light by replacing the dichroic mirror, commonly used in fluorescence confocal microscopy, with a 50/50 beam splitter. "Optical slicing" in the x-y plane, coupled with precision z-axis stepping allows for the detection of the gasliquid interface by blocking out-of-focus light. Copyright © 2011 by ASME.
Publication Title
ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011
Recommended Citation
Hernandez, J.,
&
Allen, J.
(2011).
Optical film thickness measurements using a reflectance mode swept-field confocal microscope.
ASME-JSME-KSME 2011 Joint Fluids Engineering Conference, AJK 2011,
2, 413-418.
http://doi.org/10.1115/AJK2011-36037
Retrieved from: https://digitalcommons.mtu.edu/michigantech-p/11746