Le Gall Antoine, Perronet Karen, Dulin David, Villing André, Bouyer Philippe, Visscher Koen, Westbrook Nathalie
Laboratoire Charles Fabry de l’Institut d’Optique, CNRS et Université Paris Sud 11, Campus Polytechnique, 2 avenue Fresnel, 91127 Palaiseau cedex, France.
Opt Express. 2010 Dec 6;18(25):26469-74. doi: 10.1364/OE.18.026469.
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.
我们展示了一种用于使用单个激光进行光镊和粒子位置检测的系统的快速直接校准方法。该方法直接利用背焦平面干涉测量法，测量的不是绝对位置而是差分位置，即被捕获粒子相对于光镊中心的位置。因此，光镊的快速逐步移动会产生被捕获粒子的脉冲响应。然后，通过拟合测量的脉冲响应，很容易得出校准参数，如探测器的空间和时间响应以及光镊的弹簧常数。
