title: Deconvolution microscopy for flow visualization in microchannels.
abstract: Quantitative visualization of microflows is often needed to evaluate the efficiency of fluid mixing, study flow properties, investigate unusual flow behavior, and verify computational fluid dynamic simulations. In this work, we explore the technique of coupling a conventional optical microscope with a computational deconvolution algorithm to produce images of three-dimensional flows in plastic microfluidic channels. The approach, called deconvolution microscopy, is achieved by (1) optically sectioning the flow in the microchannel by collecting a series of fluorescence images at different focal planes along the optical axis and (2) removing the out-of-focus fluorescence signal by a deconvolution method to reconstruct the corrected three-dimensional concentration image. We compare three different classes of deconvolution algorithms for a uniform concentration test case and then demonstrate how deconvolution microscopy is useful for flow visualization and analysis of mixing in microfluidic channels. In particular, we employ the method to confirm the presence of twisting flows in a microchannel containing microfabricated ridges.
authors.affiliation: Department of Mechanical and Aerospace Engineering and Department of Biomedical Engineering, University of Florida, P.O. Box 116250, Gainesville, Florida 32611, USA.
authors.forename: Zheng
authors.initials: Z
authors.lastname: Xia
authors.forename: Lou
authors.initials: L
authors.lastname: Cattafesta
authors.forename: Z Hugh
authors.initials: ZH
authors.lastname: Fan
mesh_terms: D000465:Algorithms; D008853:Microscopy / Q000379:methods*