Apparatus for measuring position of fine particle

摘要

A device for measuring the three-dimensional position of a single particle (208) in a solution comprises a pulsed laser (201); a microscope system for irradiating a single particle with a laser beam (203) emitted from a pulsed laser (201); a photodetector (209) for detecting light dispersed by the single particle; a computer (211) for recording the signal detected by the photodetector (209) as displacement data and processing it; and a high-speed A/D board (210) for introducing the signal detected by photodetector (209) into the computer (211). Timing is set for data input so that the signal detected by the photodetector (209) may be input to the computer (211) at the moment of laser irradiation. It is possible to measure the position of a particle of nanometer size in real time with accuracy of nanometer order.