We propose a novel dual-channel Surface Plasmon Resonance (SPR) fiber sensors based on the incident angle adjusting method. By grinding fiber tip to form wedge-shape with different angles, we can easier adjust the incident angle in fiber, and then the SPR wavebands will change corresponding. The simulation and experiment demonstrate that the SPR wavebands will red-shift with increasing of the fiber grinding angle. Based on this, we cascade two fiber tips whose grinding angles are 5° and 15° respectively. Under the tests of the refractive index (RI) range from 1.333 to 1.385, the SPR wavebands are 576~683nm and 677~955nm respectively. Therefore, we can demodulate SPR signal by wavelength division multiplexing (WDM) technology. Sequentially, we can detect two analytes simultaneously. This dual-channel SPR fiber sensor has important significance in the fields of multichannel liquid refractive indices and temperature selfreference measurements.
We propose and demonstrate a novel fiber surface plasmon resonance (SPR) sensor based on a twin-core fiber (TCF). We grind the TCF tip into a frustum wedge shape, and plate a 50nm sensing gold film on the end face, two 500nm reflected gold films on the side faces of the wedge. We launch light source into the core of the TCF by using the high accuracy three-dimensional adjusting mount and microscope objective system. This SPR probe can be combined with microfluidic chip, and realize the real-time monitoring of the refractive index (RI) sensing of flow liquid in the microfluidic channel. The probe successfully monitors the refractive index of liquid ranged from 1.33 to 1.37 and the average sensitivity reaches to 5213nm/RIU in the solution.