Internal suspension core optical fiber grating temperature self-compensation microfluidic sensor and internal suspension core optical fiber

Abstract

The invention provides an internal suspension core optical fiber grating temperature self-compensation microfluidic sensor. An internal suspension core optical fiber is provided with two fiber cores, wherein the first fiber core (1) is arranged on the inner wall of an optical fiber inner pore duct (2), and the second fiber core (3) is arranged in a ring band-shaped cladding layer (4) of the optical fiber; a fiber grating (5) and a fiber grating (6) which have the same structure are respectively written into the same longitudinal positions of the two fiber cores; the fiber grating (5) and the fiber grating (6) are respectively taken as a sensing unit and a reference unit; the optical fiber inner pore duct (2) is taken as a micro-channel of a sample sensing place; the surface of the micro-channel is provided with micropores (8 and 9); a light source (16) is connected with a standard optical fiber (11) by a coupler (17); the standard optical fiber (11) is connected with the internal suspension core optical fiber (10) by a first tapering point (13); the divided beams respectively enter the fiber core (1) and the fiber core (3), pass through the fiber grating (5) and the fiber grating (6), and finally enter a standard optical fiber (12) after being coupled; the standard optical fiber (12) is connected with a spectrograph (18). The grating temperature self-compensation microfluidic sensor can be used for the multiple fields of medicine, environment detection, food and the like, is accurate in detection result and is not influenced by the environment temperature.

Description

technical field [0001] The invention relates to a microfluidic sensing device in an optical fiber, in particular to a high-sensitivity microfluidic fiber grating on-line sensor based on an optical fiber containing an inner suspension core. Background technique [0002] Fiber Bragg gratings are widely used in the field of sensing, and can be easily embedded in optical fiber systems and sensors to form many optical fiber devices with unique properties, which greatly promotes the development of fiber Bragg grating application technology. Its reflection or transmission peak position is related to the period length of the grating and the refractive index of the fiber core. When external physical quantities such as temperature, strain, and the environment outside the fiber core change, it will affect the refractive index modulation period of the fiber grating and the refractive index of the fiber core. , thus causing the change of the reflection or transmission peak of the fiber g...

AI Technical Summary

Problems solved by technology

Although this type of fiber Bragg grating sensor has the superior characteristics of fiber Bragg grating, it can use the resonant wavelength for concentration detection and obtain high signal-to-noise ratio. However, most fiber Bragg grating sensors are prepared by traditional optical fibers at present. The sample needs to be in contact with the fiber Bragg grating from the outside of the fiber. Sensing can only be realized by using a sample cell, which not only increases the sampling amount, but is also not conducive to device integration

Images