Prospects for Developing Pressure and Tactile Sensors Based on Surface Plasmon Resonance

In this work, one examines the prospects of using the surface plasmon resonance (SPR) effect in the Otto configuration for pressure and deformation sensing. An open Otto chip device was employed, and the chip was characterized by the use of an automated reflectometer operating at a wavelength of $\boldsymbol {\lambda } = 975.1$ nm. The active area of the device was characterized by reflectometry-based profilometry. Significant modulation of the SPR effect due to a variable gas pressure was observed at a fixed point on the device's active area. A gap reduction to approximately 50% of its nominal value was observed when the gas pressure changed from 1.7 to 0.28 bar. In addition, profilometry characterization in conjunction with a rigorous regression analysis allowed determining, unambiguously, the gap profile of the device under fixed stress. The results indicate that the technique is feasible for either pressure or tactile sensing applications.