Optical fiber multi-parameter sensing system and method

An optical fiber multi-parameter sensing system, comprising a light source, a optical circulator, a fiber-tip probe sensor and an optical spectrum analyzer, wherein

• the light source is connected to a first port of the optical circulator, to transmit a light wave outputted from the light source into the optical circulator;
• an input end of the fiber-tip probe sensor is connected to a second port of the optical circulator, and a terminal end that may be placed into an analyte to measure analyte molecules;
• said light wave outputted from the second port of the optical circulator corresponds to incident light waves of the fiber-tip probe sensor;
• the incident light wave propagates from the input end to the terminal end of the fiber-tip probe sensor losses energy at the terminal end of the fiber-tip probe sensor, which excites fiber-tip leaky modes;
• and the remaining incident light wave is reflected light wave, which is reflected back into the optical circulator after propagating from the terminal end to the input end of the fiber-tip probe sensor;
• the optical spectrum analyzer is connected to a third port of the optical circulator and is configured to (a) receive a signal of the reflected light wave for detecting a resonance wavelength and a resonance intensity of the reflected light wave;
• (b) determine, based on a shifting of the resonance wavelength of the reflected light wave, a surface parameter of the analyte to measure said surface parameter being the thickness of a dielectric layer formed from the analyte molecules on an end facet of the fiber-tip probe sensor;
• (c) determine, according to a changing of the resonance intensity of the reflected light wave, a bulk parameter, said bulk parameter being a bulk refractive index of the analyte around the fiber-tip probe sensor.