System and method for demodulating fiber bragg gratings based on liquid crystal F-P cavity adjustable filter technology

A fiber grating demodulation and fiber grating technology, which is applied in the direction of using optical devices to transmit sensing components, can solve the problems of low yield, slow control time and high process requirements, achieve compact structure, improve high and low temperature characteristics, reduce The effect of echo interference

Inactive Publication Date: 2014-06-04
HUBEI UNIV OF TECH
View PDF7 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, the multi-channel fiber grating sensor demodulator mainly adopts the technical solution based on MEMS F-P cavity tunable filter, and the technical solution of angle tunable filter type tunable filter; MEMS F-P cavity filter adopts piezoelectric ceramic technology. The technology has high requirements on the process, so the yield is not high and the price is expensive; while the angle-tunable filter type tunable filter technology usually adopts a motor drive scheme, and the biggest disadvantage of the motor is that its control time is slow and its service life is limited. , and the volume is also large, so these aspects limit its mass application

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • System and method for demodulating fiber bragg gratings based on liquid crystal F-P cavity adjustable filter technology
  • System and method for demodulating fiber bragg gratings based on liquid crystal F-P cavity adjustable filter technology
  • System and method for demodulating fiber bragg gratings based on liquid crystal F-P cavity adjustable filter technology

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0033] refer to figure 1 , fiber grating demodulation system based on liquid crystal F-P cavity tunable filtering technology, including ASE broadband light source 1, optical isolator ISO2, liquid crystal F-P cavity tunable filter LC-TOF3, 1*2 coupler 4, calibration wavelength 5, mini - PD detector 6, TEC temperature controller 7, 1*N coupler 8, circulator array 9, multi-channel FBG fiber grating 10, mini-PD detector array 11. The broadband light source emitted by ASE broadband light source 1 is isolated by the optical isolator ISO2 and then enters the liquid crystal F-P cavity tunable filter LC-TOF3 to form a narrow-band light source with variable center wavelength. The calibration wavelength is 5, and then it is converted into a narrow-band calibration electrical signal through the photoelectric mini-PD detector 6, and the other channel passes through the 1*N coupler 8, enters through the 1 port of the circulator array 9, and enters the multi-channel FBG fiber grating through...

Embodiment 2

[0043] refer to figure 2 , fiber grating demodulation system based on liquid crystal F-P cavity tunable filtering technology, including ASE broadband light source 1, optical isolator ISO2, liquid crystal F-P cavity tunable filter LC-TOF3, 1*2 coupler 4, calibration wavelength 5, mini - PD detector 6, TEC controller 7, 1*N coupler 8, 1*2 coupler array 12, multi-channel FBG fiber grating 10, mini-PD detector array 11.

[0044] The broadband light source emitted by ASE wide light source 1 is isolated by the optical isolator ISO2 and then enters the liquid crystal F-P cavity tunable filter LC-TOF3 to form a narrow-band light source with variable center wavelength, and passes through 1*2 coupler 4 splitting light all the way into the single channel calibration wavelength 5. After the photoelectric mini-PD detector 6 is converted into a narrow-band calibration electrical signal, the other channel passes through the i*N coupler 8 and then enters through the 2 ports of the 1*2 couple...

Embodiment 3

[0047] refer to image 3 , fiber grating demodulation system based on liquid crystal F-P cavity tunable filtering technology, including SLED broadband light source 13, optical isolator ISO2, liquid crystal F-P cavity tunable filter LC-TOF3, 1*2 coupler 4, calibration wavelength 5, mini - PD detector 6, TEC controller 7, 1*N coupler 8, circulator array 9, multi-channel FBG fiber Bragg grating 10, mini-PD detector array 11.

[0048] The working principle of the embodiment of the present invention is: the broadband light source emitted by the SLED wide light source 13 is isolated by the optical isolator ISO2 and then enters the liquid crystal F-P cavity tunable filter LC-TOF3 to form a narrow-band light source with a variable central wavelength, which is coupled by 1*2 The light splitter 4 enters the single-channel calibration wavelength 5, and then converts it into a narrow-band calibration electrical signal through the photoelectric mini-PD detector 6, and the other channel pas...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a system and method for demodulating fiber bragg gratings based on the liquid crystal F-P cavity adjustable filter technology. The liquid crystal F-P cavity adjustable filter technology is adopted so that the wave length demodulation performance can be improved and cost can be reduced. Meanwhile, the IL of the whole system is reduced through an annular device structure, the demodulation detection power is improved, the light source performance is improved through an opto-isolator ISO, echo interference is reduced, the performance of a whole demodulator is improved, the reliability of the system is enhanced, the function of efficient fiber bragg grating demodulation of a multichannel array is achieved through a multichannel array annular device and an array detector mini-PD structure, practicality is high, the performance is excellent, cost is low, reliability is high, and therefore production in batches is easy.

Description

technical field [0001] The invention belongs to the technical field of optical fiber sensing and relates to a multi-channel integrated high-precision optical fiber grating wavelength demodulation system, which is especially suitable for the wavelength demodulation and application of low-cost, high-performance, high-integration and multi-channel dense sensing systems. Background technique [0002] When the physical quantity of the fiber grating environment changes, the refractive index of the grating core will change, that is, the period of the grating will change, so that the wavelength of the reflected light will change. By demodulating the change in wavelength, the object to be measured can be measured Therefore, fiber gratings can be used for sensing and measuring physical quantities such as temperature, strain and stress. [0003] With the early application of fiber gratings in materials industry, chemical medicine, water conservancy and hydropower, electric power, ships...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01D5/353
Inventor 丁善婷聂磊王妍翟中生华中平
Owner HUBEI UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products