title: Measurement of the trapping efficiency of an elliptical optical trap with rigid and elastic objects.
abstract: Optical tweezers and their various modifications offer a sophisticated way to perform noncontact cell manipulation. In this paper, we quantify forces existing in an elliptical trap formed by two cylindrical lenses and compare the results with a point optical trap case. The trapping efficiency of point and elliptical traps was analyzed by measuring the Q values of both traps. Polystyrene microspheres and red blood cells (RBCs) were used as samples. Stretching of the RBC was taken into account in the Q value measurements. Although the Q value of a point optical trap is larger than that of an elliptical trap when measured for a single RBC, we can manipulate the orientation of an RBC in a point trap with the elliptical trap and can also trap several RBCs simultaneously in the elliptical trap far from the cuvette surfaces by using a long-working-distance water immersion objective. This opens new possibilities for studying light-matter interactions at the cellular level.
authors.affiliation: Optoelectronics and Measurement Techniques Laboratory, Department of Electrical Engineering, University of Oulu, Oulu, Finland. kau@paju.oulu.fi
authors.forename: Antti
authors.initials: A
authors.lastname: Kauppila
authors.forename: Matti
authors.initials: M
authors.lastname: Kinnunen
authors.forename: Artashes
authors.initials: A
authors.lastname: Karmenyan
authors.forename: Risto
authors.initials: R
authors.lastname: Myllylä
mesh_terms: D000465:Algorithms; D004548:Elasticity; D004867:Equipment Design; D004912:Erythrocytes; D006801:Humans; D008863:Microspheres; D061848:Optical Imaging / Q000295:instrumentation* / Q000379:methods; D052898:Optical Tweezers; D011137:Polystyrenes; D012542:Scattering, Radiation
chemical_list: D011137:Polystyrenes