An in-line intrinsic Fabry-Perot (FP) refractive index (RI) sensor is demonstrated. The sensor consists of a short single-mode fiber section with removed cladding that is fusion spliced between two lead fibers containing in-fiber mirrors. Measured medium that surrounds de-claded fiber section affects the fundamental mode’s effective index and consequently optical path length of the FP interferometer. Sensors with different diameters of the de-claded region were produced and experimentally evaluated within the RI range between 1.33 and 1.444. The sensitivity up to 830 nm/RIU was achieved. The proposed sensor can be interrogated by standard spectrally resolved interrogators, widely used in fiber Bragg grating sensor systems.
COBISS.SI-ID: 15419414
This paper presents a high-sensitivity, all-silica, all-fiber Fabry- Perot strain-sensor. The proposed sensor provides a long active length, arbitrary length of Fabry-Perot cavity, and low intrinsic temperature sensitivity. The sensor was micro-machined from purposely-developed sensor-forming fiber that is etched and directly spliced to the lead-in fiber. This manufacturing process has good potential for cost-effective, highvolume production. Its measurement range of over 3000 ìå, and strainresolution better than 1 ìå were demonstrated by the application of a commercial, multimode fiber-based signal processor.
COBISS.SI-ID: 15204118
The paper presents an open-path, all-fiber microcell and a micromachining method for its production. The proposed micromachining method utilizes the selective etching of a purposely designed phosphorus-doped fiber that is spliced in between two standard lead-in fibers. Microcells with various open optical-path lengths were successfully demonstrated. The proposed microcell can be used as a transmission cell or as a miniature Fabry-Perot resonator. The transmission losses and fringe contrast were experimentally investigated over a range of prototype microcells with different lengths. For example, the insertion losses below 1 dB were demonstrated for 50 mu m or shorter open path prototype microcells, when immersed in dematerialized water.
COBISS.SI-ID: 15222550