Experimental Set-up for Micro-MFV
A
micro-MFV system has been developed
to measure thin film flow fields in micro-scale thermo-meniscus
devices. The system utilizes a magnified objective lens, caged fluorescence
probe molecules of less than 10 nm in size, Nd:YAG laser for UV
emission for cleaving of the caging compound, Ar-ion laser tuned
at 488nm for pumping of fluorescence and an intensified CCD camera
to record high-resolution fluorescent-images.
The dye used is a Dextran
caged fluorescent probe (excited
at 488nm:bule and emission bend centered at 518nm:yellow) that is
initially unable to fluoresce, but upon exposure to the ultraviolet
radiation of Nd:YAG laser (355nm), the caging chemical group on
the compound is cleaved.
Lagrangian
mapping of flow field is measured by sequentially recording the
trace of uncaged dye molecule pattern using a CCD video camera.