title: Simultaneous calibration of optical tweezers spring constant and position detector response.
abstract: 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.
authors.affiliation: Laboratoire Charles Fabry de l’Institut d’Optique, CNRS et Université Paris Sud 11, Campus Polytechnique, 2 avenue Fresnel, 91127 Palaiseau cedex, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Le Gall
authors.forename: Karen
authors.initials: K
authors.lastname: Perronet
authors.forename: David
authors.initials: D
authors.lastname: Dulin
authors.forename: André
authors.initials: A
authors.lastname: Villing
authors.forename: Philippe
authors.initials: P
authors.lastname: Bouyer
authors.forename: Koen
authors.initials: K
authors.lastname: Visscher
authors.forename: Nathalie
authors.initials: N
authors.lastname: Westbrook
mesh_terms: D000465:Algorithms; D002138:Calibration; D055119:Elastic Modulus; D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000295:instrumentation / Q000379:methods; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods* / Q000592:standards; D038622:Internationality; D052898:Optical Tweezers / Q000592:standards*; D013314:Stress, Mechanical