title: Laser-Doppler velocity profile sensor with submicrometer spatial resolution that employs fiber optics and a diffractive lens.
abstract: We report a novel laser-Doppler velocity profile sensor for microfluidic and nanofluidic applications and turbulence research. The sensors design is based on wavelength-division multiplexing. The high dispersion of a diffractive lens is used to generate a measurement volume with convergent and divergent interference fringes by means of two laser wavelengths. Evaluation of the scattered light from tracers allows velocity gradients to be measured in flows with submicrometer spatial resolution inside a measurement volume of 700-microm length. Using diffraction optics and fiber optics, we achieved a miniaturized and robust velocity profile sensor for highly resolved velocity measurements.
authors.affiliation: Professorship for Measuring and Testing Techniques, Dresden University of Technology, D-01062 Dresden, Germany. buettner@iee.et.tu-dresden.de
authors.forename: Lars
authors.initials: L
authors.lastname: Büttner
authors.forename: Jürgen
authors.initials: J
authors.lastname: Czarske
authors.forename: Hans
authors.initials: H
authors.lastname: Knuppertz
mesh_terms: D004867:Equipment Design; D019544:Equipment Failure Analysis; D005336:Fiber Optic Technology / Q000295:instrumentation*; D017078:Laser-Doppler Flowmetry / Q000295:instrumentation* / Q000379:methods; D007909:Lenses; D044085:Microfluidics / Q000295:instrumentation* / Q000379:methods; D055100:Optical Fibers; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers