If the incident angle of a light beam on the boundary surface between the thin metal film of a surface plasmon resonance (SPR) apparatus and a test medium is equal to or very near the resonant angle, then the phase difference between the p- and s-polarizations of the reflected light is related to the associated physical parameter. The phase difference can be measured accurately with heterodyne interferometry. If the relationship between the phase difference and the associated physical parameter is specified, then the associated physical parameter can be estimated from the phase difference data. This method has the benefits of both common-path interferometry and heterodyne interferometry, such as simple structure, high stability, high resolution, easy operation, and rapid real-time measurement.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering