Nanometer Indicating System Based on Surface Plasma Wave

摘要

A new method for nanometer positioning based on surface plasma wave is reported. A fiber probe approaching a coated prism can be equivalent to a four-layer prism-metal-air-fibre system. Analysis of the near-field beam intensity entering the fibre probe is presented. Theoretical anaysis shows that the intensity coupling into the fibre probe changes according to the thickness of air gap. Non-contact nanometer indicating system can be set up according to this characteristic. Experiments show that standard deviation of 2nm and resolution of 0.1nm/nV of positioning repeatability can be achieved under air conditioning of +-1 deg C/h.