High-resolution wide-dynamic range electronically scanned white-light interferometry

A novel high-resolution wide-dynamic range electronically scanned white-light interferometry-based interrogation technique is presented. By using off-the-shelf optical components, this technique is capable of reaching a subnanometer resolution. The technique relies on a simple optical setup in which the wedge and camera axes are mutually inclined for a very small angle in the horizontal plane and two-dimensional fringe pattern analysis. Resolution below 0.3 nm and dynamic range of 106 dB have been achieved with a signal-to-noise ratio lower than 25 dB.