High-speed video-based tracking of optically trapped colloids

TY - JOUR

T1 - High-speed video-based tracking of optically trapped colloids

AU - Otto, O

AU - Gornall, J.L.

AU - Stober, G.

AU - Czerwinski, Fabian

AU - Siedel, R.

AU - Keyser, U.F.

PY - 2011/4/1

Y1 - 2011/4/1

N2 - We have developed an optical tweezer setup, with high-speed and real-time position tracking, based on a CMOS camera technology. Our software encoded algorithm is cross-correlation based and implemented on a standard computer. By measuring the fluctuations of a confined colloid at 6000 framess-1, continuously for an hour, we show our technique is a viable alternative to quadrant photodiodes. The optical trap is calibrated by using power spectrum analysis and the Stokes method. The trap stiffness is independent of the camera frame rate and scales linearly with the applied laser power. The analysis of our data by Allan variance demonstrates single nanometer accuracy in position detection.

AB - We have developed an optical tweezer setup, with high-speed and real-time position tracking, based on a CMOS camera technology. Our software encoded algorithm is cross-correlation based and implemented on a standard computer. By measuring the fluctuations of a confined colloid at 6000 framess-1, continuously for an hour, we show our technique is a viable alternative to quadrant photodiodes. The optical trap is calibrated by using power spectrum analysis and the Stokes method. The trap stiffness is independent of the camera frame rate and scales linearly with the applied laser power. The analysis of our data by Allan variance demonstrates single nanometer accuracy in position detection.

U2 - 10.1088/2040-8978/13/4/044011

DO - 10.1088/2040-8978/13/4/044011

M3 - Journal article

SN - 0972-8821

VL - 13

SP - 044011

JO - Journal of Optics (India)

JF - Journal of Optics (India)

IS - 4,SI

ER -