Temperature detection system based on Michelson interference structure

A technology of interference structure and detection system, which is applied to thermometers, thermometers, and measuring devices with physical/chemical changes, which can solve the problems of variable frequency, difficult to filter out, unfavorable optical fiber sensors, etc., and achieve small phase detection errors , Wide range of applications, and the effect of improving sensing accuracy

Inactive Publication Date: 2018-12-18
JILIN UNIV
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, on the one hand, the high-frequency component itself will affect the phase detection of the cosine wave (the position of the zero-crossing point changes); The electrical characteristics are equivalent to capacitance, and the voltage at both ends cannot jump, so the falling edge of the sawtooth wave cannot be infinitely short) and the elasticity of the optical fiber itself and many other factors, the frequency is variable, and it is difficult to filter out cleanly; and , when using a filter, in addition to affecting the amplitude-frequency characteristics of the output signal, it will also affect the phase-frequency characteristics of the signal at the same time, that is, the phase of the filter will be affected near the cut-off frequency, which is very important for relying on phase changes. It is very disadvantageous for fiber optic sensors that measure changes in stress

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
  • Temperature detection system based on Michelson interference structure
  • Temperature detection system based on Michelson interference structure
  • Temperature detection system based on Michelson interference structure

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 2

[0028] Embodiment 2 function transformation circuit

[0029] The structure of the function conversion circuit 28 is that one end of the capacitor C3 is connected to the pin 12 of the trigonometric function converter U1 and one end of the resistor R2, and the other end of the capacitor C3 is used as the input terminal of the function conversion circuit 28, which is recorded as the port ACOS_in , is connected with the output end of the second photoelectric conversion circuit 27; the other end of the resistor R2 is grounded; the pins 2, 3, 4, 5, 8, 11, 13 of the trigonometric function converter U1 are grounded, and the pins 9, 10 are connected to the capacitor One end of C2 is connected to -12V power supply, the other end of capacitor C2 is grounded; pin 6 of trigonometric function converter U1 is connected to pin 7, pin 16 is connected to +12V power supply and one end of capacitor C1, and the other end of capacitor C1 Grounding; pin 1 of the trigonometric function converter U1 i...

Embodiment 3

[0030] Embodiment 3 Adaptive Amplitude Normalization Circuit

[0031] Because the amplitude of the signal output by the function conversion circuit 28 is small, and is affected by multiple parameters in the optical path and the circuit, the size is indefinite, so the present invention designs an adaptive amplitude normalization circuit 29, which is used to convert the signal output by the function conversion circuit 28 The amplitude is normalized to the optimal size to further improve the accuracy of demodulation. The specific structure is as image 3As shown, one end of the capacitor C9 is connected to one end of the resistor R3 and the pin 3 of the chip U2, the other end of the resistor R3 is grounded, and the other end of the capacitor C9 is used as the input end of the adaptive amplitude normalization circuit 29, which is recorded as the port ADAPT_in, It is connected with the port ACOS_out of the function conversion circuit 28; the pin 1, the pin 7, the pin 8 and the pin ...

Embodiment 4

[0032] Embodiment 4 phase comparison circuit

[0033] like Figure 4 As shown, the structure of the phase comparison circuit 30 used in the present invention is that one end of the capacitor C10 is connected to the non-inverting input end of the op amp U5 and one end of the resistor R13, and the other end of the capacitor C10 is used as an input end of the phase comparison circuit 30. The port PHASE_in1 is connected to the port ADAPT_out of the adaptive amplitude normalization circuit 29; the other end of the resistor R13 is grounded; the positive power supply terminal of the operational amplifier U5 is connected to the +5V power supply, the negative power supply terminal is grounded, the inverting input terminal is grounded, and the output terminal is connected to The CLK end of D flip-flop U6A; the D port of D flip-flop U6A is grounded; one end of capacitor C11 is grounded, and the other end is connected to the PR end of D flip-flop U6A; one end of resistor R14 is connected ...

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
Bandwidthaaaaaaaaaa
Center wavelengthaaaaaaaaaa
Login to view more

Abstract

The invention relates to a temperature detection system based on a Michelson interference structure and belongs to the technical field of optical fiber sensors. The temperature detection system mainlycomprises a pumping source (1), a first optical coupler (2), an optical wavelength division multiplexer (3) and the like. The temperature detection system provided by the invention uses a sinusoidalsignal as a modulating signal, can not produce high-frequency interference and has the characteristics of more reliable work, high sensing precision and wide application range.

Description

technical field [0001] The invention belongs to the technical field of optical fiber sensors, in particular to a temperature detection system based on Michelson interference structure. Background technique [0002] Fiber Bragg grating (FBG) is widely used in the field of sensing technology due to its advantages of anti-electromagnetic interference, chemical resistance, small transmission loss, small size and light weight, and easy mass production. At present, temperature sensors play an important role in safe production, especially in high-risk places such as mines, where temperature monitoring is crucial. However, most of the traditional temperature sensors are realized by the change of electrical signal, and the temperature sensor based on the change of electrical signal is greatly limited in practical application. Additional safety hazards, on the other hand, when used in harsh environments, they are greatly disturbed by the environment and the transmission is inconvenie...

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): G01K11/32G01K11/3206
CPCG01K11/32
Inventor 汝玉星杨忠岗孙茂强于广安毕琳旭
Owner JILIN 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