![Fig. 9.1 — Optical tweezers calibration](https://i0.wp.com/opticaltweezers.org/wp-content/uploads/2015/11/Fig9_1.png?fit=660%2C331)
Trap stiffness κx of the optical tweezers realised in Chapter 8 when holding a polystyrene spherical particle with radius a = 1.03 μm as a function of the trapping laser power P at the sample, obtained with (a) mean squared displacement analysis, (b) autocorrelation function analysis and (c) power spectrum analysis. The resulting κx is linear in P and the three measurements are in very good agreement.
Fig. 9.1 — Optical tweezers calibration