CN220982299U - Environment state monitoring system - Google Patents

Abstract

The utility model relates to an environmental condition monitoring system, comprising: the light emitting module is used for emitting first broadband light; the optical transmission module is connected with the optical emission module and is used for receiving the first broadband light and splitting the first broadband light into a plurality of second broadband lights; the optical sensing module comprises a plurality of fiber bragg grating sensors positioned in the target monitoring environment, and the fiber bragg grating sensors are used for receiving the second broadband light and reflecting the narrowband light to the optical transmission module; and the plurality of optical demodulation modules are connected with the optical transmission module and are used for receiving the narrow-band light reflected by each fiber grating sensor transmitted by the optical transmission module and determining the monitoring value of the target monitoring environment based on the narrow-band light. The environment state monitoring system provided by the utility model is provided with the plurality of narrow-band lights reflected by the fiber bragg grating sensors, and converts the state value of the target monitoring environment, so that a plurality of positions or a plurality of types can be monitored simultaneously.

Description

Environment state monitoring system

Technical Field

The utility model relates to the technical field of optical fibers, in particular to an environment state monitoring system.

Background

The optical fiber sensing technology is a technology which takes light as a carrier, takes optical fibers as a sensing unit and a propagation medium, and is mainly used for inverting the change of an external environment field through the change of characteristic quantity when the light is transmitted in the optical fibers.

In the traditional technology, the change amount of the external environment field is directly calculated through the change of the optical fiber characteristic quantity, the problem of low precision is solved, and the monitoring mode is single, so that a monitoring system capable of monitoring the change of the environment field with high precision is required to be developed.

Disclosure of utility model

Based on this, it is necessary to provide an environmental condition monitoring system for the problem of low accuracy in simply calculating the external environmental field change amount by using an optical fiber in the conventional art.

The application provides an environment state monitoring system. The environmental condition monitoring system includes:

The light emitting module is used for emitting first broadband light;

The optical transmission module is connected with the optical emission module and is used for receiving the first broadband light and splitting the first broadband light into a plurality of second broadband lights;

The optical sensing module comprises a plurality of fiber bragg grating sensors positioned in the target monitoring environment, and the fiber bragg grating sensors are used for receiving the second broadband light and reflecting the narrowband light to the optical transmission module; and

And the plurality of optical demodulation modules are connected with the optical transmission module and are used for receiving the narrow-band light reflected by each fiber grating sensor transmitted by the optical transmission module and determining the monitoring value of the target monitoring environment based on the narrow-band light.

In one embodiment, the target monitoring state of the target monitoring environment includes at least one of temperature, pressure and vibration, and the plurality of fiber grating sensors includes at least one of a temperature fiber grating sensor, a pressure fiber grating sensor and a vibration fiber grating sensor.

In one embodiment, the optical transmission module includes a branching unit for branching the first broadband light into a plurality of second broadband lights and transmitting the second broadband lights to the coupling unit, and the coupling unit is for transmitting the plurality of second broadband light couplings to the respective fiber bragg grating sensors, and the coupling unit is further for transmitting the plurality of narrowband light couplings to the respective optical demodulation modules.

In one embodiment, the wavelength of the first broadband light emitted from the light emitting module is greater than or equal to 1530 nm and less than or equal to 1565 nm.

In one embodiment, the optical demodulation module determines the monitoring value according to the characteristic value by determining the characteristic value of the narrowband light based on a correlation between the characteristic value and the monitoring value.

In one embodiment, the optical demodulation module is configured to determine a wavelength of the narrowband light, and determine the monitoring value according to the wavelength of the narrowband light based on a correlation between a preset wavelength of the narrowband light and the monitoring value.

In one embodiment, the optical demodulation module includes:

A temperature determination unit for determining a current temperature;

the light splitting sheet is arranged on the light path of the narrow-band light and is used for splitting the narrow-band light into reflected light and transmitted light;

A first conversion unit that receives the reflected light and converts the reflected light into a first electrical signal;

a second conversion unit that receives the transmitted light and converts the transmitted light into a second electrical signal; and

And the processor is used for calibrating according to the current temperature, determining the wavelength of the narrowband light based on the first electric signal and the second electric signal, and determining the monitoring value of the target monitoring environment based on the wavelength of the narrowband light.

In one embodiment, the optical demodulation module further includes a collimator, and the collimator is disposed on an optical path of the narrowband light, so that the narrowband light enters the beam splitter after being collimated by the collimator.

In one embodiment, a filter is further disposed between the light splitting sheet and the second conversion unit, so that the transmitted light enters the second conversion unit after being filtered by the filter.

In one embodiment, the optical demodulation module further comprises a temperature control unit, and the temperature control unit is used for adjusting the temperature of the light splitting sheet, the first conversion unit, the second conversion unit and/or the processor.

The environment state monitoring system comprises a light emitting module, a light transmission module, a light sensing module and a light demodulation module, wherein the light sensing module comprises a plurality of fiber bragg grating sensors used for monitoring a target monitoring environment, the light emitting module emits first broadband light, the light transmission module divides the first broadband light into a plurality of second broadband light and enters the fiber bragg grating sensors, narrowband light is obtained through reflection of the fiber bragg grating sensors and is transmitted to the light demodulation module through the light transmission module, and the light demodulation module obtains a state value of the target monitoring environment in a conversion mode by determining characteristic values of the narrowband light. By means of the method, on one hand, the average value can be determined by comparing the monitoring results, and the accuracy is improved; on the other hand, the method can synchronously monitor a plurality of positions or a plurality of categories of the target monitoring environment to obtain a plurality of monitoring results.

Drawings

FIG. 1 is a schematic diagram of an environmental condition monitoring system according to an embodiment.

Detailed Description

In order that the above objects, features and advantages of the utility model will be readily understood, a more particular description of the utility model will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model. The present utility model may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the utility model, whereby the utility model is not limited to the specific embodiments disclosed below.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

Referring to fig. 1, fig. 1 is a schematic structural diagram of an environmental condition monitoring system according to an embodiment of the utility model. In one exemplary embodiment, the environmental condition monitoring system includes a light emitting module 110, a light transmitting module 120, a light sensing module 130, and a plurality of light demodulating modules 140. The light emitting module 110 is configured to emit a first broadband light, the light transmitting module 120 is connected to the light emitting module 110, and is capable of receiving the first broadband light emitted by the light transmitting module and splitting the first broadband light into multiple second broadband lights with the same wavelength, where the multiple second broadband lights all enter the light sensing module 130. The optical sensing module 130 includes a plurality of fiber grating sensors 132 (FBG sensors Fiber Bragg Grating) located in a target monitoring environment as a monitoring object, so that a state of the target monitoring environment can be sensed by the fiber grating sensors 132. The plurality of fiber grating sensors 132 form a plurality of monitoring units that may be disposed at a plurality of locations or for monitoring of a plurality of status types. After receiving the second broadband light, the fiber bragg grating sensor 132 reflects the narrowband light, and transmits the obtained narrowband light to the optical transmission module 120 again, and transmits the narrowband light to the optical demodulation module 140 via the optical transmission module 120. The optical demodulation module 140 receives the narrowband light transmitted by the optical fiber grating sensor 132 through the optical transmission module 120, so that the narrowband light reflected by each optical fiber grating sensor 132 is demodulated by the corresponding optical demodulation module 140, and the monitoring value of the target monitoring state of the target monitoring environment is determined by the optical demodulation module 140. Illustratively, the monitored value may be a temperature value, a pressure value, or a vibration amplitude of the target monitored environment.

The fiber grating sensor 132 operates on the principle of bragg diffraction in the optical fiber based on the grating, measures and monitors changes in physical quantity by using the optical fiber of the grating structure, and has the characteristics of high sensitivity, high resolution, electromagnetic interference resistance, corrosion resistance, and the like. The grating is formed by inserting periodic refractive index changes in the core of the fiber. When the second broadband light passes through the grating, bragg diffraction occurs, i.e. a specific frequency of the light is reflected back, resulting in narrowband light. This particular frequency depends on the period of the grating and the refractive index of the fiber. When the physical quantity changes, for example, the temperature rises or the pressure rises, the refractive index of the optical fiber changes, so that the Bragg diffraction frequency is changed, the characteristic of the narrow-band light changes, and the monitoring value of the target detection state changed by the target monitoring environment can be obtained by measuring the change of the characteristic value. Schematically, narrowband light appears to shift in wavelength, and by measuring this wavelength change, a monitored value can be derived.

Illustratively, the target detection states that the fiber grating sensor 132 can monitor include temperature, pressure, stress, and the like. Accordingly, the state change of the target monitoring environment may be a temperature change, a pressure change, and/or a vibration, and the narrowband light whose characteristics are changed can be obtained based on such state change, so that the change value of the physical quantity of the state of the target monitoring environment is obtained based on the narrowband light reverse conversion. When the fiber grating sensor 132 is disposed at a plurality of different positions of the target monitoring environment, the states of the different positions can be monitored. Optionally, after the status of the different locations is obtained, the mean may be calculated to improve accuracy. Such as monitoring the temperature at different locations simultaneously.

Based on the difference of the packaging modes, the fiber bragg grating sensor can be manufactured into a temperature fiber bragg grating sensor which is only sensitive to temperature, a pressure fiber bragg grating sensor which is only sensitive to pressure and a vibration fiber bragg grating sensor which is only sensitive to vibration. The plurality of fiber bragg grating sensors comprise at least one of a temperature fiber bragg grating sensor, a pressure fiber bragg grating sensor and a vibration fiber bragg grating sensor, wherein when the plurality of fiber bragg grating sensors comprise two or three of the temperature fiber bragg grating sensor, the pressure fiber bragg grating sensor and the vibration fiber bragg grating sensor, the change of different state types of the target monitoring environment under the same time can be monitored, and the temperature and vibration can be monitored simultaneously.

Compared with the method for only singly monitoring the environmental physical quantity in the prior art, the technical scheme provided by the embodiment can synchronously monitor a plurality of positions or a plurality of types of environmental states by splitting the first broadband light into a plurality of second broadband lights which respectively enter a plurality of types of fiber bragg grating sensors.

During monitoring, the light emitting module 110 continuously emits a first broadband light, thereby generating a second broadband light that continuously passes into the fiber grating sensor 132. When the state of the target monitoring environment is not changed, the reflected narrowband light is continuously maintained in the first state, once the state of the target monitoring environment is changed, the reflected narrowband light is correspondingly changed, so that the narrowband light is in the second state in the state change period, the optical demodulation module 140 can determine the characteristic change amount of the target monitoring environment based on the difference between the second state and the first state, and when the monitoring value of the target monitoring environment in the first state is acquired, the monitoring value of the second state can be determined based on the characteristic change amount of the narrowband light.

In one embodiment, the monitoring values of the narrowband light characteristics in one-to-one correspondence are determined in advance through experiments, and a correlation retrieval table, such as a table of temperature values corresponding to narrowband light wavelengths, is constructed. After determining the characteristic value of the narrowband light by the optical demodulation module 140, a lookup is performed in the correlation table based on the obtained characteristic value to obtain a uniquely determined characteristic value.

In another embodiment, during the monitoring process, the continuous second broadband light is introduced into the fiber bragg grating sensor 132, and the narrowband light obtained by the optical demodulation module 140 is maintained in the first state while the state of the target monitoring environment is maintained constant and unchanged, and the wavelength is maintained at a constant value. Once the state of the target monitoring environment is changed, the state of the narrowband light is changed and is in the second state, the narrowband light is shifted relative to the wavelength of the first state in the second state, and after the monitoring value of the target monitoring environment in the first state is determined, the optical demodulation module can determine the monitoring value of the target monitoring environment in the second state based on the wavelength shifting direction and the shifting amount.

Illustratively, a plurality of second broadband lights are respectively input into each fiber bragg grating sensor 132, so that each fiber bragg grating sensor 132 can play a role in monitoring. The number of the fiber bragg grating sensors 132 is consistent with the number of the second broadband lights, so that a plurality of second broadband lights enter each fiber bragg grating sensor 132 one by one, and the optical sensing module 130 is provided with a plurality of monitoring units, so that a plurality of positions or a plurality of types can be monitored at the same time.

The light emitting module 110 may include a broadband light source 112. Broadband light source 112 is a device or apparatus capable of providing an optical signal over a broad spectrum of wavelengths that emits light at a plurality of different wavelengths with relatively small spacing between the wavelengths to form a broad spectrum of light, i.e., a first broad band of light. Illustratively, broadband light source 112 may be a C-band first broadband light source capable of providing a source of C-band spectrum.

The spectral range of the C-band may be between 1530 nm and 1565 nm, and may be the end point. The C band has lower optical fiber transmission loss and better optical fiber nonlinearity, so that the C band is widely applied to long-distance, high-speed and high-capacity optical fiber communication systems. Illustratively, the C-band first broadband light source includes, but is not limited to, an ASE (AMPLIFIED SPONTANEOUS EMISSION ) light source, an edge-emitting light source, or the like.

The optical transmission module 120 is connected to the optical emission module 110, illustratively, may be connected in an optical fiber, to receive the first broadband light. After receiving the first broadband light, the optical transmission module 120 splits the first broadband light to obtain a plurality of second broadband lights. The first broadband light is illustratively split by a splitter for splitting an incoming optical signal into two or more output channels. The first broadband light is divided into a plurality of channels when passing through the splitter, thereby converting the first broadband light into a plurality of second broadband lights. Illustratively, the splitter may be a 1*2 splitter to split the first broadband light into two paths of second broadband light, and further, a plurality of splitters may be sequentially disposed to obtain multiple paths of second broadband light.

After splitting the first broadband light into the second broadband light, the optical transmission module 120 is further configured to transmit the second broadband light into the optical sensing module 130. In one possible implementation, referring to fig. 1, the optical transmission module 120 may include a branching unit 122 and a coupling unit 124, where the branching unit 122 is configured to branch the first broadband light into a plurality of second broadband lights and transmit the second broadband lights to the coupling unit 124, the coupling unit 124 is configured to transmit the plurality of second broadband lights to the plurality of fiber bragg grating sensors 132, and the plurality of narrowband lights are reflected by the plurality of fiber bragg grating sensors 132, and the coupling unit 124 is further configured to transmit the plurality of narrowband lights to the respective corresponding optical demodulation modules 140. Illustratively, the coupling unit 124 makes the second broadband light correspond to the one-to-one coupling of the fiber bragg grating sensor 132, and makes the narrowband light emitted by the fiber bragg grating sensor 132 correspond to the corresponding optical demodulation module 140 one-to-one.

In one possible implementation, the optical transmission module 120 is composed of a PLC (PLANAR LIGHTWAVE Circuit, planar waveguide Circuit) splitter. PLC splitters, also known as fiber splitters or fiber couplers, are optical devices based on optical waveguide technology that can uniformly distribute an input optical signal to multiple output channels or combine multiple input signals into one output. In particular, in the present embodiment, the PLC splitter may uniformly distribute the first broadband light to the plurality of output channels, thereby outputting the plurality of second broadband lights. The plurality of narrowband lights may also be output to the optical demodulation module 140, respectively.

The PLC splitter can be an integrated chip, a substrate is made by adopting a semiconductor technology (photoetching, corrosion, development and the like), the optical waveguide chip is positioned on the surface of the substrate, the splitting function is integrated on the optical waveguide chip, the two ends of the optical waveguide chip are respectively packaged in a coupling way by using a multi-channel optical fiber array, when light enters from an incident end, the light can equally divide power to each channel through the chip and is output from the output end of each channel, and the characteristics of each channel of light are consistent. Specifically, the first broadband light is input to the incident end, and the second broadband light is output from the output end. Optionally, the PLC splitter may be configured by using 1×2×8 PLC chips or 1×16 &1×2×16 PLC chips. Wherein 1 represents the number of input channels and the latter number represents the number of output channels, and the specific number of channels can be customized according to the actual requirements.

In the embodiment, a PLC branching unit is used for replacing a multipath 1*2 tapered coupler, the size is reduced by more than 2/3, the cost is reduced, and the more the number of channels is, the more the cost advantage is obvious.

In an exemplary embodiment, the optical demodulation module 140 includes a light splitting sheet 141, a first conversion unit 142, a second conversion unit 143, a temperature determining unit 144, and a processor (not shown in the figure), where the light splitting sheet 141 is disposed on an optical path of the narrowband light, and the temperature determining unit 144 is used to determine the current temperature, and the narrowband light portion is reflected by the light splitting sheet 141 to obtain reflected light and enters the first conversion unit 142, and is converted into a first electrical signal by the first conversion unit. The narrow-band light portion is transmitted through the light splitting sheet 141 to obtain transmitted light and enters the second conversion unit 143, and is converted into a second electrical signal through the second conversion unit. The processor performs calibration according to the current temperature, determines a wavelength value of the narrow-band light based on the values of the first electric signal and the second electric signal, and determines a monitoring value based on a correlation between the wavelength value and a monitoring value of the target monitoring environment.

The temperature determination unit 144 is capable of detecting the current temperature. Illustratively, the temperature determining unit 144 includes a thermistor, which may be disposed at any position of the optical demodulation module 140, through which the current temperature is determined. Optionally, the temperature measurement range of the thermistor is between-50 degrees celsius and 150 degrees celsius.

The beam splitter 141 is capable of splitting an incident light beam into two or more light beams, and in this embodiment, the narrow band light is partially reflected and partially transmitted through the beam splitter 141. The reflected portion is defined as reflected light, which enters the first conversion unit 142, and the transmitted portion is defined as transmitted light, which enters the second conversion unit 143. Optionally, the light-splitting sheet 141 is coated with a depolarizing film and a light-splitting film, where the depolarizing film is used to convert polarized light into unpolarized light, eliminate or weaken polarization effect of the light, improve accuracy and reliability of measurement, and the light-splitting film is used to split incident narrowband light into different directions according to a specific ratio, so that the light is reflected to the first conversion unit 142, and the light-splitting ratio can take a constant value of 20% -80%.

Illustratively, the first conversion unit 142 and/or the second conversion unit 143 may comprise a semiconductor material, based on the photoelectric effect, by directly converting the energy of the light into a voltage or power value by utilizing the principles of photoelectron excitation and carrier generation present in the semiconductor material, thereby enabling the processor to scale based on the voltage, power value. The first conversion unit 142 may be used as a reference path, and the second conversion unit 143 may be used as a signal path.

In one possible implementation, the first conversion unit 142 converts the reflected light into a first electrical signal U1, the second conversion unit 143 converts the transmitted light into a second electrical signal U2, and the processor is configured to obtain a proportional relationship between the first electrical signal U1 and the second electrical signal U2, determine a correlation between the proportional relationship and a current temperature, and determine a wavelength value of the narrowband light according to the correlation. Illustratively, the proportional relationship of the first electrical signal U1 and the second electrical signal U2 may be represented by K1 or K2, where k1=u2/(u1+u2), k2=u2/U1. After constructing the correlation between K1, K2 and the current temperature, the wavelength value is characterized based on the correlation. Specifically, the wavelength value is determined by λ=a×k+b, where λ is a wavelength value, a and B are constants, and are related to the temperature T, and are preset by external calibration.

And each temperature T corresponds to a group of K1-Kn and λ1- λn (n is the calibrated wavelength number), the temperature T is controlled to be gradient from the outside in actual calibration, the number is more than or equal to 3, and finally a three-dimensional matrix corresponding relation is formed. Thus, after determining the current temperature, a corresponding narrowband optical wavelength value can be obtained based on K1 and K2. Schematically, when the corresponding relation between the proportional relation among the temperature, the first electric signal and the second electric signal and the wavelength value is constructed, the gap is filled in an interpolation fitting mode due to the existence of the temperature gradient and the wavelength gradient, so that the corresponding precision can be improved, and the system measurement precision is improved. Optionally, the interpolation temperature gradient step is less than 1 ℃, and the interpolation wavelength step is less than 0.1nm.

In one embodiment, the optical demodulation module 140 further includes a collimator 145, where the collimator 145 is disposed on an optical path of the narrowband light, and the narrowband light enters the beam splitter 141 after being collimated by the collimator 145. The collimator 145 serves to focus the light rays, reducing the spreading and spreading effects of the light beams, making them more parallel and concentrated, for focusing the light beams into more parallel rays. In this embodiment, after the collimator 145 is provided, the narrow-band light output from the optical transmission module 120 to the optical demodulation module 140 can be converged, so that the narrow-band light entering the beam splitter 141 is more converged, and the beam quality is improved.

In one embodiment, a filter 146 is further disposed between the light splitting sheet 141 and the second conversion unit 143, and the transmitted light enters the second conversion unit 143 after being filtered by the filter 146. The filter 146 can selectively transmit or block light in a specific wavelength range, and can enhance or attenuate light in certain wavelengths as required, thereby achieving the purpose of screening, separating or adjusting light. In this embodiment, the transmitted light is filtered by the filter 146 to remove stray light.

In one embodiment, the optical demodulation module 140 further includes a temperature control unit (not shown in the drawing) for adjusting the temperatures of the beam splitter 141, the first conversion unit 142, the second conversion unit 143, and the processor. Optionally, the temperature control unit may also control the temperature of the collimator 145 and the filter 146. The temperature control unit controls the optical demodulation module 140 to be a preset temperature value, and the processor can directly calculate the wavelength value of the narrow-band light according to the preset temperature value as the current temperature value, so that the current temperature is not required to be determined by the temperature determination unit, and the influence of stable fluctuation on a calculation result is avoided, so that the test precision is improved.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (10)

1. An environmental condition monitoring system, the environmental condition monitoring system comprising:

The light emitting module is used for emitting first broadband light;

The optical transmission module is connected with the optical emission module and is used for receiving the first broadband light and splitting the first broadband light into a plurality of second broadband lights;

The optical sensing module comprises a plurality of fiber bragg grating sensors positioned in a target monitoring environment, and the fiber bragg grating sensors are used for receiving the second broadband light and reflecting the narrowband light to the optical transmission module; and

And the plurality of optical demodulation modules are connected with the optical transmission module and are used for receiving the narrow-band light reflected by each fiber grating sensor transmitted by the optical transmission module and determining the monitoring value of the target monitoring environment based on the narrow-band light.

2. The environmental condition monitoring system of claim 1, wherein the target monitoring condition of the target monitoring environment comprises at least one of temperature, pressure, and vibration, and the plurality of fiber bragg grating sensors comprises at least one of temperature fiber bragg grating sensors, pressure fiber bragg grating sensors, and vibration fiber bragg grating sensors.

3. The environmental condition monitoring system of claim 1, wherein the optical transmission module includes a branching unit for branching the first broadband light into a plurality of second broadband lights and transmitting the second broadband lights to the coupling unit, the coupling unit for transmitting the plurality of second broadband light couplings to the fiber bragg grating sensors, and the coupling unit further for transmitting the plurality of narrowband light couplings to the optical demodulation modules.

4. The environmental condition monitoring system of claim 1 wherein the wavelength of the first broadband light emitted by the light emitting module is 1530 nm or more and 1565 nm or less.

5. The environmental condition monitoring system of claim 1 wherein the optical demodulation module determines the monitored value from the characteristic value by determining the characteristic value of the narrowband light based on a correlation of the characteristic value and the monitored value.

6. The environmental condition monitoring system of claim 5, wherein the optical demodulation module is configured to determine the wavelength of the narrowband light, and determine the monitored value based on a preset correlation between the wavelength of the narrowband light and the monitored value.

7. The environmental condition monitoring system of claim 6 wherein the optical demodulation module comprises:

A temperature determination unit for determining a current temperature;

the light splitting sheet is arranged on the light path of the narrow-band light and used for splitting the narrow-band light into reflected light and transmitted light;

a first conversion unit that receives the reflected light and converts the reflected light into a first electrical signal;

A second conversion unit that receives the transmitted light and converts the transmitted light into a second electrical signal; and

And the processor is used for calibrating according to the current temperature, determining the wavelength of the narrow-band light based on the first electric signal and the second electric signal, and determining the monitoring value of the target monitoring environment based on the wavelength of the narrow-band light.

8. The environmental condition monitoring system of claim 7, wherein the optical demodulation module further comprises a collimator disposed on the optical path of the narrowband light such that the narrowband light enters the beam splitter after being collimated by the collimator.

9. The environmental condition monitoring system according to claim 7, wherein a filter is further disposed between the beam splitter and the second conversion unit, such that the transmitted light enters the second conversion unit after being filtered by the filter.

10. The environmental condition monitoring system of claim 7, wherein the optical demodulation module further comprises a temperature control unit for adjusting the temperature of the light splitting sheet, the first conversion unit, the second conversion unit, and/or the processor.