Simultaneous calibration of optical tweezers spring constant and position detector response

Antoine Le Gall (1) , Karen Perronet (1) , David Dulin (1) , André Villing (2) , Philippe Bouyer (2) , Koen Visscher (2, 3) , Nathalie Westbrook (1)

1 Laboratoire Charles Fabry de l'Institut d'Optique / Otique atomique - bio
2 laboratoire Charles Fabry de l'Institut d'Optique / Optique atomique
3 Departments of Physics, Molecular and Cellular Biology, and College of Optical Sciences, University of Arizona, Tucson

We demonstrate a fast and direct calibration method for systems using a single laser for optical tweezers and particle position detection. The method takes direct advantage of back-focal-plane interferometry measuring not an absolute but a differential position, i.e. the position of the trapped particle relative to the center of the optical tweezers. Therefore, a fast step-wise motion of the optical tweezers yields the impulse response of the trapped particle. Calibration parameters such as the detector's spatial and temporal response and the spring constant of the optical tweezers then follow readily from fitting the measured impulse response.

Mots clés: biophotonique

Domaines: Biophysique; Optique [physics.optics]

Antoine Le Gall, Karen Perronet, David Dulin, André Villing, Philippe Bouyer, et al.. Simultaneous calibration of optical tweezers spring constant and position detector response. Optics Express, 2010, 18 (25), pp.26469. ⟨10.1364/OE.18.026469⟩. ⟨hal-00546528⟩