Micro nano optical fiber grating refractive index sensor

Abstract

The invention discloses a micro nano optical fiber grating refractive index sensor, the sensor comprises a broadband light source, an optical coupling element and a micro nano optical fiber grating which are successively connected, and a wavelength detection unit which is connected with the optical coupling element; the broadband light source emits optical signals and the optical signals are subjected to incidence to the micro nano optical fiber grating after passing through the optical coupling element, reflected through the micro nano optical fiber grating and passed through the incident light wavelength detection unit of the optical coupling element again; wherein the refractive index susceptibility of two polarization direction Bragg reflection peaks of the micro nano optical fiber grating are different, and the temperature sensitive degree of two polarization direction Bragg reflection peaks of the micro nano optical fiber grating are same. Two reflection peaks have different sensitivity to external environment refractive index, the reflection peak of the low wave length has larger refractive index sensitivity, when the external environment refractive index is increased, and the wavelength difference of two reflection peaks is decreased. The sensor provided by the invention has the advantages of simple structure, simple realization and regulation method and accurate measure result.

Description

technical field [0001] The invention relates to the field of optical fiber grating refractive index sensors, in particular to a micro-nano optical fiber grating refractive index sensor. Background technique [0002] As one of the most important photonic devices in the 20th century, fiber Bragg gratings (referred to as fiber gratings) are widely used in the fields of optical fiber sensing and optical fiber communication due to their small size, high sensitivity, wavelength coding, and anti-electromagnetic interference. [0003] In terms of refractive index and biochemical sensing, micro-nano fiber gratings combine micro-nano fibers with fiber grating technology. On the one hand, the large evanescent field of micro-nano fibers can interact with the outside world. The advantages of fiber gratings provide good conditions for the detection of the refractive index of its external environment. [0004] Therefore, it has become the trend and main development direction of the indust...

AI Technical Summary

Problems solved by technology

[0007] Calibrating micro-nano fiber gratings in series with ordinary fiber gratings can eliminate the temperature response. However, introducing multiple gratings will cause structural complexity and is not suitable for practical applications.

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