title: Technique for mechanical measurements using optical scattering from a micropipette.
abstract: This communication proposes an optical method using forward light scattering to measure the deflection of a micropipette from a normal contact force with a small elastic solid, and the damping coefficient of a small fluid sample through a dynamic interaction with the pipette. An analytical and experimental study of this sensor is performed and described for each property. Topics covered include: 1) forward light scattering technique for determining the diameter of a micropipette (using exact and simplified geometric interference theories); 2) deflection measurement and analysis on the pipette-sample system using the finite element method; and 3) equivalent damping coefficient and resonant frequency measurement of the pipette-fluid system and its numerical solution derived from the finite element model. A comparison of the experimental results and the analytical results is included to provide the means for analyzing the potential of this new method.
authors.affiliation: Department of Electrical Engineering FT-10, University of Washington, Seattle 98195.
authors.forename: W C
authors.initials: WC
authors.lastname: Wang
authors.forename: M
authors.initials: M
authors.lastname: Afromowitz
authors.forename: B
authors.initials: B
authors.lastname: Hannaford
mesh_terms: D003198:Computer Simulation; D004867:Equipment Design; D008846:Micromanipulation / Q000295:instrumentation* / Q000379:methods; D055095:Optics and Photonics; D012371:Robotics; D012680:Sensitivity and Specificity