Characterization of trapping force in the presence of spherical aberration |
| |
Authors: | Pu Chun Ke Min Gu |
| |
Affiliation: | Optoelectronic Imaging Group, Department of Applied Physics , Victoria University of Technology , PO Box 14428 MCMC, Victoria, 8001, Australia |
| |
Abstract: | Abstract Transverse trapping force in laser tweezers is investigated in the presence of spherical aberration caused by the refractive-index mismatch between a cover slip and the water solution where particles are suspended. The transverse trapping efficiency is characterized in terms of the numerical aperture of a microscope objective and the thickness of a sample cell. It has been experimentally demonstrated that the spherical aberration can be compensated for by changing the effective tube length of an objective used for trapping. As a result, the transverse trapping efficiency can be improved by up to 20%. In principle, a further improvement in the trapping efficiency is possible if an objective of an infinitely-long tube length is used. |
| |
Keywords: | |
|
|