Optical shield: measuring viscosity of turbid fluids using optical tweezers.
The viscosity of a fluid can be measured by tracking the motion of a suspended micron-sized particle trapped by optical tweezers. However, when the particle density is high, additional particles entering the trap compromise the tracking procedure and degrade the accuracy of the measurement. In this work we introduce an additional Laguerre-Gaussian, i.e. annular, beam surrounding the trap, acting as an optical shield to exclude contaminating particles.
School of Physics and Astronomy, SUPA, University of Glasgow, UK. m.lee.2@research.gla.ac.uk
M P
MP
Lee
A
A
Curran
G M
GM
Gibson
M
M
Tassieri
N R
NR
Heckenberg
M J
MJ
Padgett
D000465:Algorithms; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009391:Nephelometry and Turbidimetry / Q000295:instrumentation*; D052898:Optical Tweezers; D014783:Viscosity