The new approach to an optical noncontact method for small displacement measurements

The ray-tracing method provides another opportunity for noncontact measurements. This kind of technique, which uses the analysis of light reflection from an object's surface, can generally be the basis for identifying the object's position in 3D space and for precise, noncontact measurement of displacement. It is very hard to determine the exact accuracy of measurement at this stage of research; this requires a case-by-case analysis. The article also discusses methods using laser interferometers and fiber optics.