Multichannel SPR sensor for single-mode fiber and multi-mode fiber cascade application

Abstract

The invention provides a multichannel surface plasma resonance (SPR) sensor for single-mode fiber and multi-mode fiber cascade application. The SPR sensor comprises a continuous spectrum light source 1, an eccentric single-mode fiber SPR sensor 2, a multi-mode fiber SPR sensor 3, a sensing membrane 2-1 of a cone angle structure, a reflective film 2-2 of multi-mode fiber, a sensing membrane 3-1 of multi-mode fiber, and a spectrometer 4. The SPR sensor having the cone angle structure is produced on the end of eccentric single-mode fiber by using a fiber grinding technology and a nano-gold membrane coating technology; multi-mode fiber is corroded, a gold membrane is spread to form the transmission-type multi-mode fiber SPR sensor; and the connection of the single-mode fiber and multi-mode fiber is performed in the way that light field transmission is realized by grinding one end of the multi-mode fiber and plating the reflective film 2-2. The multichannel SPR sensor has wavelength division multiplexing characteristic, sensitivity after cascade is not reduced, binary channel liquid refractive measurement is realized, and the sensor has important meaning for analytes detection, background refractive index interference elimination, and temperature self-reference.

Description

technical field [0001] The invention belongs to the field of optical fiber SPR sensors, in particular to a multi-channel SPR sensor for cascade application of single-mode optical fibers and multi-mode optical fibers. Background technique [0002] SPR sensors are usually based on the Kretschmann (Z. Naturforsch, 1968, 2135-2136) structure, consisting of a thin highly conductive metal layer covering the surface of a prism. The properties of its reflection spectrum are highly sensitive to the refractive index of the medium adjacent to the outside of the metal layer. The basic principle of the SPR sensor determines that the response measured by this sensor is caused by many factors. In the most commonly used biomedical measurement field, in addition to the combination of the molecule to be measured and the probe to change the dielectric constant of the sensitive film, In addition to changing the resonance angle or resonance wavelength (specific response), other components in th...

AI Technical Summary

Problems solved by technology

However, sapphire fiber is expensive, and it is difficult to change the fiber core material for fiber-optic SPR sensors.

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