用于光阱刚度测量的位置传感器标定实验研究

Calibration of position sensitive sensor for optical trap stiffness measurement

对位置传感器的标定通常采用压电陶瓷平台驱动样品池,使固定在样品池底部的直径为2.5μm的聚苯乙烯微球穿过轴向位置不同的光阱,由位置传感器获取微球的位移信息。实验结果表明,当光阱在轴向不同位置时,传感器探测灵敏度有差别。实测中应采用微球和光阱处于相同轴向位置的标定结果。

For the calibration of the position sensitive sensor, piezoelectric ceramic drive platlorm is usea to anve me sampxe pool, on the floor of which a polystyrene sphere with a diameter of φ2.5 μm is fixed. The micro sphere is passed through an optical trap at different axial position;the displacement of the micro sphere is obtained by position sensitive sensor. The experimental re suits show that, as the optical trap is located at different axial position, the sensitivity of the sensor varies. In the practice, the cali bration result from the case that the micro sphere and the optical trap are at the same axial position is adopted.