Figure 5
From: Calibration of force detection for arbitrarily shaped particles in optical tweezers
Experimental sketches and results using absolute calibration: (a,b) Spherical particle in a non-linear region of the force (silica in water, d = 2.2 μm). (c,d) RBC in Stokes flow. Fluid drag force acting on the trapped RBC in plasma for different stage velocities. The drag force is that acting on an oblate spheroid of the same size (5.0 × 8.4 μm) as the RBC. (e,f) The blob in Stokes flow. The inset images show the change in shape of the blob as the flow speed changes. Modelled as a prolate spheroid with parameters ranging from 5.3 × 6.8 μm to 4.8 × 8.8 μm. (g,h) Birefringent vaterite microsphere in Stokes flow (vaterite in ethanol, d = 1.1 μm). (i,j) Spherical particle trapped in an HG10 beam in Stokes flow (polystyrene in water, d = 3.1 μm). Insets in figures (a,c,e,g,i) shows trapped object (bottom) and laser intensity mode (upper).
