High resolution angular measurement using surface-plasmon-resonance heterodyne interferometry at optimal incident wavelengths

Abstract

We have recently demonstrated that ultra high resolution of angular measurement down to 10-6 degree can be achieved via surface-plasmon-resonance heterodyne interferometry, in which the phase difference between p- and s- polarized reflected waves is monitored as a function of the incident angle. Here we give a brief summary of this technique and the rationale based on which such a measurement is possible. As a further study, we have also investigated, via simulation, how the change in environmental temperature will affect the resolution limit of this very versatile technique.