Optical fiber microbubble concentration sensor based on nano-gold film and its sensing method

Abstract

The invention belongs to the field of optical fiber technology, and specifically provides an optical fiber microbubble concentration sensor and a sensing method based on a nano-gold film, which are used to realize the measurement of liquid concentration. The present invention is based on the photothermal effect of the nano-gold film. The optical fiber microbubble concentration sensor is composed of a single-mode optical fiber and a nano-gold film uniformly sputtered on the flat end surface of the single-mode fiber; the sensor is immersed in a liquid environment, and the light provided by the laser The energy is transmitted through a single-mode optical fiber, emitted from the flat end of the optical fiber, irradiated on the nano-gold film, and micro-bubbles are formed at the nano-gold film, and the change of the size of the micro-bubbles per unit time is detected by microscopic imaging technology to realize the transmission of the liquid concentration. sense. The invention provides an optical fiber microbubble concentration sensor with simple structure, small volume, low cost and flexible operation, which can sense the concentration information at any position in the microfluidic system; and adopts microscopic imaging technology to directly observe changes in microbubbles, reducing The operational difficulty and cost of detection.

Description

technical field [0001] The invention belongs to the field of optical fiber technology, relates to an optical fiber microbubble concentration sensor, and specifically provides an optical fiber microbubble concentration sensor based on the photothermal effect of a nano-gold film and a sensing method thereof. Background technique [0002] Due to the advantages of high sensitivity, anti-electromagnetic interference, small size and light weight, optical fiber sensors are widely used in petrochemical, electric power, medicine, civil engineering and many other fields in terms of communication and sensing technology. Most of the traditional optical fiber sensors use micro-processing technology to process micro-nano structures on the optical fiber, such as Farper micro-interference cavities, fiber gratings, etc., and realize sensing by changing the spectral characteristics of the sensor's transmitted or reflected light waves with the measured changes. This type of fiber optic sensor ...

AI Technical Summary

Problems solved by technology

This type of fiber optic sensor has high sensitivity and accurate measurement, but the manufacturing process is relatively complicated, and the high-precision spectral demodulation instrument also greatly increases the cost of the device, and even requires the ability of the operator, which limits its application range

[0003] In order to overcome the above problems, the application number is: 201610871752, and the patent name is: the Chinese patent of optical fiber microbubble method sensor and its sensing method discloses a carbon nanotube film coated on the end surface of the optical fiber, through the heat transfer of the carbon nanotube film performance, produce microbubbles, and realize the measurement of physical quantities such as flow velocity and temperature; however, this sensor can only be used for the measurement of physical quantities in liquid environments, and is not suitable for liquid concentration measurement

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