PDH-demodulated polarization-maintaining grating FP cavity temperature strain simultaneous measurement device

A temperature strain and measurement device technology, applied in the field of photoelectric detection, can solve the problems that the physical environment cannot be guaranteed to be completely consistent, the offset of the grating is not the same, and the additional noise cannot be completely eliminated, so as to achieve temperature stability and anti-vibration stability The effect of good performance, reduction of extra noise, and simple structure

Active Publication Date: 2019-06-21
HARBIN ENG UNIV
View PDF14 Cites 15 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Due to the difference in fiber grating manufacturing process, the offset of the grating is often caused by the change of strain and temperature, which will introduce additional measurement errors
At the same time, due to the use of dual fiber grating resonators, it is impossible to ensure that the physical environment of the two fiber gratings is exactly the same, so it is impossible to completely eliminate the additional noise caused by temperature.

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
  • PDH-demodulated polarization-maintaining grating FP cavity temperature strain simultaneous measurement device
  • PDH-demodulated polarization-maintaining grating FP cavity temperature strain simultaneous measurement device
  • PDH-demodulated polarization-maintaining grating FP cavity temperature strain simultaneous measurement device

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0026] A PDH demodulated polarization maintaining grating FP cavity temperature and strain simultaneous measurement device. The narrow linewidth tunable laser is sequentially connected with the optical fiber isolator 003, the Y waveguide modulator 004, the polarization maintaining optical fiber circulator 006, and the polarization maintaining optical fiber through the polarization maintaining optical fiber. The grating FP cavity 007 is connected, and the other end of the polarization-maintaining fiber circulator 006 is connected with the polarization beam splitting module and the demodulation module 014 in turn through the polarization-maintaining fiber, and the demodulation module 014 is connected with the control terminal computer 015, and the signal generator 008 passes through The polarization-maintaining optical fiber is respectively connected with the Y-waveguide modulator 004 and the demodulation module 014, and the polarization beam splitting module is that the first out...

Embodiment 2

[0045] The present invention is based on the improvement of PDH optical fiber grating technology strain measurement method, in order to isolate the information of temperature and strain, eliminate as far as possible the problem of the environment due to temperature and strain between different optical fiber gratings, use polarization maintaining optical fiber grating to solve temperature and strain The separation problem of , which works as figure 1 shown. Frequency-sweeping laser 002 driven by triangular wave generator 001 generates frequency-sweeping laser, which is sent to Y-waveguide 004 driven by standard sine generator 008 after passing through isolator 003 for PDH signal modulation. Y-waveguide converts the two polarizations of the input laser Axis separation, and output modulated laser light on a certain polarization axis. The generated modulated laser signal is welded to the back-end polarization-maintaining fiber through 45°, so that when the transmitted light passe...

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

PropertyMeasurementUnit
Attenuation coefficientaaaaaaaaaa
Login to view more

Abstract

A PDH-demodulated polarization-maintaining grating FP cavity temperature strain simultaneous measurement device belong to the technical field of photoelectric detection. The device comprises an ultra-narrow line width light source, a light source frequency sweeping device, a polarization maintaining fiber grating, a polarization beam splitting device, and a quadrature demodulation device; and a narrow line width tunable laser is driven by a triangular wave to provide a swept source, a Y-waveguide modulated signal is welded to a rear optical fiber at 45 degrees, polarization separation is performed on a reflected signal by PBS, detection of temperature and strain is performed by utilizing characteristics of an FP cavity of the polarization maintaining fiber grating, an accurate frequency shift signal of a harmonic peak is obtained by utilizing a PDH technology, and temperature and strain signals are simultaneously solved by physical properties of two polarization axes of the FP cavity of the polarization maintaining fiber grating. Beneficial effects of the device are that: a demodulation port utilizes two quadrature demodulation systems to demodulate a signal to obtain the signal with a higher signal-to-noise ratio, the test precision is improved, and the device can be used for manufacturing of high-precision fiber grating temperature and strain sensors under harsh environmentalconditions.

Description

technical field [0001] The invention belongs to the technical field of photoelectric detection, and in particular relates to a device for simultaneously measuring temperature and strain of a polarization-maintaining grating FP cavity for PDH demodulation. Background technique [0002] Fiber Bragg Grating (FBG) sensors have been effectively applied in smart materials and structural monitoring due to their small size, high-speed response characteristics, and easy reuse. However, for high-precision temperature and strain observation, a single fiber grating cannot meet the requirements because the reflection peak is too wide. Therefore, fiber gratings can be used to form a resonant cavity to reduce the width of the reflection peak and obtain more accurate observation signals. Therefore, many improved FBG measurement schemes have been proposed, such as using phase-shifted FBG and FBG interferometer instead of ordinary FBG, and using laser frequency locking technology to improve ...

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): G01K11/32G01B11/16G01K11/3206
Inventor 杨军张毅博田帅飞邹晨祝海波苑勇贵李寒阳苑立波
Owner HARBIN ENG UNIV
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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap