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3D Particle Trajectories Observed by Orthogonal Tracking Microscopy
Published
Author(s)
Matthew D. McMahon, Andrew J. Berglund, Peter T. Carmichael, Jabez J. McClelland, James A. Liddle
Abstract
We demonstrate high-resolution, high-speed 3D nanoparticle tracking using angled micromirrors. When angled micromirrors are introduced into the field of view of an optical microscope, reflected side-on views of a diffusing nanoparticle are projected alongside the usual direct image. The experimental design allows us to find the 3D particle trajectory using fast, centroid-based image processing, with no nonlinear computing operations. We have tracked polystyrene particles of 190 nm diameter with position measurement precision <20 nm in 3D with 3 ms frame duration (i.e., at an imaging rate >330 frames per second). Because the image processing requires only ≈1 ms per frame, this technique could enable real-time feedback-controlled nanoparticle assembly applications with nanometer precision.
McMahon, M.
, Berglund, A.
, Carmichael, P.
, McClelland, J.
and Liddle, J.
(2009),
3D Particle Trajectories Observed by Orthogonal Tracking Microscopy, ACS Nano, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=620605
(Accessed October 10, 2025)