Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1537984 | Optics Communications | 2011 | 5 Pages |
In this study an alternative method based on surface plasmon resonance is proposed for in-situ monitoring of variation in the refractive index of a test sample. A wavelength-modulated light source and an unequal-path-length optical configuration heterodyne interferometer are used to detect the phase difference change, which can then be used to estimate the change in the refractive index of a test sample. The experimental results demonstrate a phase stability of 0.02°. The resolution power of the refractive index is 1.5 × 10− 6 RIU. This method has several advantages over previously used methods such as simple optical setup, easier operation in real time, and low cost.
Research Highlights►Heterodyne interferometry consists of wavelength-modulated light and unbalanced path. ►Surface plasmon resonance phase is detected by WM heterodyne interferometry. ►In-situ monitoring of variation in the refractive index of a test sample.