Fundamental Analysis on the Novel 3-D Probing Technique for Micro- parts Using the Optical Fiber Trapping

A novel three-dimensional probing technique for microparts with high aspect ratios is proposed. In this technique, a particle trapped optically at the optical fiber tip is used as a probe for position detection. In order to confirm the feasibility of this method, this paper demonstrates numerical computations about the optical force exerted on the probe sphere and the behavior of position detection signal using finite-difference time-domain method and Maxwell stress tensor. It is found that the optical force induced at the tapered fiber tip can trap the probe sphere three-dimensionally, and it has the performance as the position detection probe.