Optical fiber sensor system, sensing signal measuring method, computer equipment and medium

Abstract

The invention relates to the technical field of optical fiber sensing, in particular to an optical fiber sensor system, a sensing signal measuring method, computer equipment and a medium. The optical fiber coupler comprises at least two optical fiber interference arms which are arranged in parallel and is used for dividing an optical signal into at least two beams and enabling the beams to be propagated along different paths to generate interference; the polarization controller is arranged at the emergent end of the optical fiber coupler and is used for regulating and controlling the polarization state and the polarization direction of the emergent light; the voltage control module is arranged on at least one optical fiber interference arm and used for changing the phase of the optical fiber by applying voltage; the image sensor is used for collecting interference fringe images and converting the interference fringe images into electric signals; and the data processing device is used for carrying out peak searching calculation on the electric signal to obtain stripe movement information, and obtaining a corresponding sensing signal value according to the relationship between the stripe movement information and the sensing signal. The application range of the interferometer in the visible light wave band is expanded, and the measurement precision of the interferometer is improved.

Description

Technical Field

[0001] The present application relates to the field of optical fiber sensing technology, and in particular to an optical fiber sensor system, a sensing signal measurement method, a computer device and a medium. Background Art

[0002] Fiber optic sensing technology is widely used in the fields of communications, industrial monitoring, medical diagnosis, etc. due to its advantages of anti-electromagnetic interference, corrosion resistance, and long transmission distance. Among them, the fiber optic Mach-Zehnder interferometer, as an important fiber optic sensing element, can achieve high-precision measurement of various physical quantities by measuring the phase difference change of light in two parallel fiber waveguide arms.

[0003] However, all-fiber Mach-Zehnder interferometers for the visible light band are very rare on the market. The reason is that the manufacturing process of all-fiber Mach-Zehnder interferometers is quite complicated, and traditional designs often cannot meet the requirements of single-mode optical fiber at a specific wavelength (such as 650nm). Summary of the invention

[0004] Based on this, it is necessary to propose an optical fiber sensor system and its sensor signal measurement method to address the technical problem of the existing technology that the all-fiber Mach-Zehnder interferometer lacks the visible light band, which solves the limitations of traditional interferometers in visible light band applications, expands the application range of interferometers in the visible light band, and improves the measurement accuracy and stability of the interferometer.

[0005] A first aspect of the present application provides an optical fiber sensor system, the system comprising:

[0006] A laser light source, used to generate an optical signal;

[0007] The optical fiber coupler comprises at least two parallel optical fiber interference arms, which are used to divide the optical signal into at least two beams and make them interfere after propagating along different paths;

[0008] A polarization controller, arranged at the output end of the optical fiber coupler, for adjusting the polarization state and polarization direction of the output light;

[0009] A voltage control module, disposed on at least one optical fiber interferometer arm, for changing the phase of the optical fiber by applying voltage;

[0010] An image sensor, used for collecting interference fringe images and converting the interference fringe images into electrical signals;

[0011] The data processing device is used to perform peak calculation on the electrical signal to obtain fringe movement information, and obtain a corresponding sensor signal value according to the relationship between the fringe movement information and the sensor signal.

[0012] Optionally, the polarization controller is used to adjust the 650nm single-mode optical fiber output light to a linear polarization state vibrating in the same direction.

[0013] Optionally, the polarization controller adjusts the number of turns of the wave plate so that the quarter wave plate is wound once and the half wave plate is wound twice to correspond to the phase delay requirement of the 650nm single-mode optical fiber.

[0014] Optionally, the coating layer at the end of the optical fiber is removed, and the optical fibers are placed in a matching glass capillary tube with equal length and in parallel, and are polished through multiple steps to ensure that the output end face is smooth.

[0015] A second aspect of the present application provides a method for measuring a sensing signal using the optical fiber sensor system, the method comprising:

[0016] The light beam of the outgoing light is regulated to be linearly polarized light vibrating in the same direction;

[0017] Collecting interference fringe images through an image sensor and converting the interference fringe images into electrical signals;

[0018] The data processing device performs peak search calculation on the electrical signal to obtain fringe movement information, and obtains the corresponding sensor signal value according to the relationship between the fringe movement information and the sensor signal.

[0019] Optionally, performing peak finding calculation on the electrical signal to obtain fringe movement information includes:

[0020] Determine the measurement area;

[0021] Acquiring a baseline within the measurement area;

[0022] Obtaining the peak value closest to the baseline;

[0023] The stripe movement direction and the number of stripes are determined according to the peak value.

[0024] Optionally, determining the stripe movement direction and the number of stripes according to the peak value includes:

[0025] Obtaining a specified number of peaks and calculating the phases of the specified number of peaks, taking one wavelength as a phase interval;

[0026] If the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the left; if the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the right;

[0027] When the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by more than +180 degrees, the number of fringes is increased by 1; when the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by less than -180 degrees, the number of fringes is decreased by 1.

[0028] Optionally, obtaining a corresponding sensor signal value according to the relationship between the stripe movement information and the sensor signal includes:

[0029] Acquire a standard sensor signal and a standard number of stripes moving under the standard sensor signal;

[0030] The ratio of the standard sensing signal to the standard number of bars is used as a standard sensing coefficient;

[0031] A corresponding sensing signal value is obtained according to the standard sensing coefficient and the number of fringes.

[0032] A third aspect of the present application provides a computer device, the computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program:

[0033] Performing peak-finding calculation on the electrical signal to obtain fringe movement information, wherein the electrical signal is obtained by converting the interference fringe image;

[0034] The corresponding sensor signal value is obtained according to the relationship between the stripe movement information and the sensor signal.

[0035] A fourth aspect of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0036] Performing peak calculation on the electrical signal to obtain fringe movement information, wherein the electrical signal is obtained by converting the interference fringe image;

[0037] The corresponding sensor signal value is obtained according to the relationship between the stripe movement information and the sensor signal.

[0038] The fiber optic sensor system, sensor signal measurement method, computer equipment and medium provided in the embodiments of the present application include a laser light source for generating a light signal; a fiber optic coupler including at least two parallel fiber optic interference arms for dividing the light signal into at least two beams and causing them to interfere after propagating along different paths; a polarization controller disposed at the output end of the fiber optic coupler for regulating the polarization state and polarization direction of the output light; a voltage control module disposed on at least one fiber optic interference arm for changing the phase of the optical fiber by applying a voltage; an image sensor for collecting interference fringe images and converting them into electrical signals; a data processing device for performing peak calculation on the electrical signal to obtain fringe movement information, and obtaining the corresponding sensor signal value according to the relationship between the fringe movement information and the sensor signal. The present application expands the application scope of the interferometer in the visible light band and improves the measurement accuracy of the interferometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] in:

[0041] Figure 1 This is a schematic diagram of the structure of the optical fiber sensor system in the embodiment of the present application;

[0042] Figure 2 Schematic diagram of the output end of the optical fiber interferometer in the embodiment of the present application;

[0043] Figure 3 is a schematic diagram of a polarization controller in an embodiment of the present application;

[0044] Figure 4 is a schematic diagram of a polarization controller in an embodiment of the present application;

[0045] Figure 5 A physical picture of the laser light source in the embodiment of the present application;

[0046] Figure 6 A physical picture of a polarization controller in an embodiment of the present application;

[0047] Figure 7 A physical picture of the piezoelectric ceramic in the embodiment of the present application;

[0048] Figure 8 A physical picture of an image sensor in an embodiment of the present application;

[0049] Fig. 9This is a schematic diagram of the interface of the sensor measurement program in the embodiment of the present application;

[0050] Fig.10 Schematic diagram of the process of the sensor signal measurement method in the embodiment of the present application;

[0051] Fig.11 A schematic diagram of an interference fringe image in an embodiment of the present application;

[0052] Fig.12 A schematic diagram of a baseline in a peak search process in an embodiment of the present application;

[0053] Fig.13 It is a schematic diagram of the structure of a computer device in an embodiment of the present application. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0055] See also Figure 1 As shown, Figure 1 A schematic diagram of a fiber optic sensor system provided in an embodiment of the present application.

[0056] Since the manufacturing process of the fiber Mach-Zehnder interferometer is relatively complicated, and the traditional design is difficult to ensure the efficient transmission characteristics of single-mode optical fiber at a specific wavelength (such as 650nm), this greatly limits its application range in the visible light band and leads to the scarcity of all-fiber Mach-Zehnder interferometer products for this band on the market. In view of this situation, this application proposes an innovative fiber optic sensor system based on fiber Mach-Zehnder interferometer, which aims to overcome the limitations of the existing technology and achieve high-precision measurement of various physical or chemical sensing signals such as temperature, concentration, vibration, etc.

[0057] The optical fiber sensor system 1 provided in the embodiment of the present application may include: a laser light source 10 , an optical fiber coupler 20 , a polarization controller 30 , a voltage control module 40 , an image sensor 50 and a data processing device 60 .

[0058] The laser light source 10 is responsible for generating an optical signal for interferometry. A laser light source is a device capable of generating laser radiation, which utilizes a specific physical process to convert electrical energy or other forms of energy into laser output. The laser light source may be a solid laser, a gas laser, a semiconductor laser, a fiber laser, or the like. In the embodiment of the present application, the wavelength of the laser light source is 650 nm. Light with a wavelength of 650 nm has less loss when transmitted in an optical fiber, and is easy to match with components such as a fiber coupler 20 and a polarization controller 30.

[0059] The optical fiber coupler 20 includes at least two parallel optical fiber interference arms, which are used to split the optical signal generated by the laser light source 10 into two beams and make them interfere after propagating along different paths. Figure 2 The output end of the optical fiber coupler 20 is shown. In the embodiment of the present application, a 650nm single-mode optical fiber 3dB coupler is selected. The 650nm single-mode optical fiber 3dB coupler has the advantages of small insertion loss, high coupling efficiency, and low wavelength sensitivity.

[0060] In an optional embodiment, the lengths of the fiber interferometer arms in the fiber coupler 20 are the same. Selecting fiber interferometer arms of equal length can minimize the optical path difference between the two interfering light waves during propagation, thereby reducing the fuzziness and instability of the interference fringes caused by the optical path difference and improving the measurement accuracy and stability of the system.

[0061] The polarization controller 30 is arranged at the output end of the optical fiber coupler 20, and is used to adjust the polarization state and polarization direction of the output light. In interference measurement, the polarization state of light has an important influence on the contrast and stability of the interference fringes. Therefore, the polarization state of the output light can be accurately controlled by the polarization controller 30 to optimize the interference effect and improve the measurement accuracy. In the embodiment of the present application, a 650nm single-mode optical fiber polarization controller is selected. The 650nm single-mode optical fiber polarization controller has the advantages of a wide range of polarization state control, high stability, and easy integration. By adjusting the parameters of the polarization controller, accurate control of the polarization state of the output light can be achieved.

[0062] See also Figure 3 and Figure 4 As shown, in order to obtain the clearest interference fringes and improve the measurement accuracy, the polarization controller 20 adjusts the polarization state of the light wave so that the two interfering light waves have the same polarization direction at the output end, thereby maximizing the contrast of the interference fringes and improving the measurement performance of the system. In specific implementation, the polarization controller adjusts the number of turns of the wave plate (a quarter wave plate is wound 1 turn, and a half wave plate is wound 2 turns) to correspond to the phase delay requirements of the 650nm single-mode optical fiber, ensuring that the output light is a linear polarization state vibrating in the same direction.

[0063] The voltage control module 40 is arranged on at least one optical fiber interference arm and is used to change the phase of the optical fiber by applying voltage. In the embodiment of the present application, piezoelectric ceramics are selected as the core component of the voltage control module. Piezoelectric ceramics have the advantages of fast response speed, large displacement, and easy control. By applying voltage to the piezoelectric ceramics, it can produce a slight deformation, thereby changing the length or refractive index of the optical fiber, thereby achieving precise control of the optical fiber phase.

[0064] The image sensor 50 is used to collect interference fringe images. Interference fringes are interference phenomena generated after light signals propagate in the optical fiber interferometer arms. The contrast, distribution and other characteristics of the interference fringes can reflect the changes in the physical quantity to be measured. In the embodiment of the present application, a high-resolution, high-sensitivity CCD image sensor is selected to ensure the clarity and accuracy of the interference fringe image.

[0065] In an optional implementation, in order to reduce the influence of the indoor lighting source on the collection of interference fringes, a light shield may be used to shield the image sensor 50 and the emission end of the optical fiber coupler 20 .

[0066] The data processing device 60 is used to convert the interference fringe image collected by the image sensor 50 into an electrical signal, and perform peak calculation on the electrical signal to obtain a sensor signal value.

[0067] In order to further ensure the stability of the interference effect, the embodiment of the present application also removes the coating of the optical fiber and then places it in parallel in a matching glass capillary. The selection of the glass capillary must ensure that it matches the refractive index of the optical fiber to reduce the reflection loss of light at the interface between the optical fiber and the capillary. At the same time, the two optical fibers are placed close together in parallel to ensure the best interference effect between the two optical fibers.

[0068] In order to ensure the smoothness of the optical fiber end face, a multi-step grinding process is used to finely process the optical fiber end, such as rough grinding, fine grinding and polishing. By optimizing the grinding process, the smoothness of the optical fiber end face can be ensured to reach the micron level, thereby improving the clarity and stability of the interference fringes.

[0069] The measurement principle of the optical fiber sensor system 1 is based on the interference effect of light. When two coherent light waves meet at the output end, the two coherent light waves will interfere and produce light and dark interference fringes. The movement and change of these interference fringes can reflect the change of the optical path difference.

[0070] The present application can use the optical fiber sensor system 1 to measure the temperature of the environment. Due to the thermal sensitivity of the optical fiber, when the ambient temperature changes, the length or refractive index of the optical fiber will change accordingly, resulting in the movement or change of the interference fringes. By measuring the change in the interference fringes, accurate measurement of the temperature can be achieved.

[0071] The present application can use the optical fiber sensor system 1 to measure the concentration of liquid. When there is a solute in the liquid, its refractive index will change, thereby affecting the optical signal transmission and interference effect in the optical fiber. By measuring the change in the interference fringes, the concentration of the liquid can be inferred.

[0072] The present application can also use the optical fiber sensor system 1 to measure the vibration of an object. When the object vibrates, it causes a slight deformation or displacement of the optical fiber, resulting in a change in the interference fringes. By measuring the change in the interference fringes, accurate measurement of the vibration of the object can be achieved.

[0073] The optical fiber sensor system 1 provided in the embodiment of the present application provides a stable optical signal through a laser light source; the interference effect is generated through the optical fiber coupler, so that the system can perform high-precision measurements on tiny physical changes; the voltage control module allows the phase of the optical fiber to be dynamically changed by applying voltage, thereby adjusting the interference fringe image, increasing the flexibility and adaptability of the system; the combination of the image sensor and the data processing device realizes the acquisition and automatic analysis of the interference fringe image, and improves the efficiency and accuracy of the measurement. By ensuring that the output light is in a linear polarization state of vibration in the same direction, the linear polarization state helps to reduce the noise caused by polarization mismatch, improves the signal-to-noise ratio of the system, thereby optimizing the stability and clarity of the interference fringe image, and improves the measurement accuracy. By accurately adjusting the number of windings of the wave plate, the phase delay of the output light of the 650nm single-mode optical fiber is accurately controlled. Accurate phase control helps to reduce the system instability factors caused by phase mismatch, thereby optimizing the interference fringe image and improving the overall stability of the system. The smooth optical fiber output end face reduces light scattering and reflection, improves the quality of the light beam and the clarity of the interference fringe image.

[0074] Please also see Figure 5-Figure 9 Next, it is described how to use the optical fiber sensor system 1 to measure the sensing signal value.

[0075] First, turn on the power of the laser light source and the power of the power meter to ensure that the fiber optic sensor system 1 can work normally. By adjusting the focusing lens adjustment frame, finely adjust the position and focal length of the lens to ensure that as much light intensity as possible can be coupled into the optical fiber. During this process, the power meter can be used to monitor the light intensity coupled into the optical fiber in real time until it reaches the maximum value. Turn on the data processing device (such as a computer, embedded system, etc.) and run the sensor measurement program. Adjust the position of the image sensor to ensure that the interference fringe image can be clearly presented in the central area of ​​the image sensor. Use an attenuator to adjust the light intensity at the output end to avoid excessive light intensity causing sensor saturation, or too low light intensity causing reduced measurement accuracy. During this process, it is necessary to constantly observe the reading of the power meter to ensure that the light intensity is within the appropriate range. Finely adjust the polarization controller to optimize the clarity of the interference fringes by changing the polarization state of the light. Observe the interference fringe image on the image sensor to ensure that the fringes are clear and stable to achieve the optimal interference effect.

[0076] Before actual measurement, the fiber optic sensor system needs to be calibrated. Use the calibration function in the sensor measurement program to calibrate the sensor to ensure that it can accurately reflect the changes in the interference fringes. During the calibration process, it may be necessary to adjust and verify the accuracy of the sensor several times until the expected accuracy requirements are achieved.

[0077] On the premise of ensuring the stability of the system and accurate calibration, start the sensor measurement program to perform actual measurements. Observe and record the changes in the interference fringes, and use the data processing device to process and analyze the measurement data in real time. Based on the measurement data, calculate the sensor signal value (such as temperature, liquid concentration, object vibration, etc.).

[0078] See also Fig.10 As shown, Fig.10 A schematic diagram of a flow chart of a sensor signal measurement method provided in an embodiment of the present application, the sensor signal measurement method comprises the following steps:

[0079] S101, adjusting the outgoing light beam to be linearly polarized light vibrating in the same direction.

[0080] In order to achieve high-precision measurement, it is necessary to control the outgoing light to be linearly polarized light that vibrates in the same direction. The polarization state and polarization direction of the outgoing light are achieved by using optical components such as polarization controllers and wave plates. The polarizer is used to select light that vibrates in a specific direction, while the wave plate can adjust the polarization state of the light to meet the measurement requirements.

[0081] In the embodiment of the present application, the polarization controller adjusts the polarization state of the light wave so that the two interfering light waves have the same polarization direction at the output end, thereby maximizing the contrast of the interference fringes. The polarization controller adjusts the number of turns of the wave plate (1 turn for the quarter wave plate and 2 turns for the half wave plate) to correspond to the phase delay requirements of the 650nm single-mode optical fiber, ensuring that the output light is a linear polarization state vibrating in the same direction.

[0082] S102, collecting an interference fringe image through an image sensor, and converting the interference fringe image into an electrical signal.

[0083] When two or more coherent light waves meet at a certain point in space, they interfere with each other to form interference fringes of light and dark. These interference fringes contain information about the phase difference of the light waves, so these interference fringes can be captured by image sensors (such as CCD image sensors or CMOS cameras), such as Fig.11 As shown in Figure 2. The image sensor converts light signals into electrical signals for subsequent data processing.

[0084] S103, performing peak search calculation on the electrical signal by a data processing device to obtain fringe movement information, and obtaining a corresponding sensor signal value according to a relationship between the fringe movement information and the sensor signal.

[0085] The data processing device can use the peak-finding algorithm to identify the peak position in the interference fringes. The peak position reflects the movement of the interference fringes and is the basis for the subsequent calculation of the sensor signal value.

[0086] In an optional implementation, performing peak finding calculation on the electrical signal to obtain fringe movement information includes:

[0087] Determine the measurement area;

[0088] Acquiring a baseline within the measurement area;

[0089] Obtaining the peak value closest to the baseline;

[0090] The stripe movement direction and the number of stripes are determined according to the peak value.

[0091] In the peak search calculation process, the measurement area must be determined first. The measurement area is the part of the interference fringe image that the user is interested in, and usually contains the interference fringes that need to be analyzed. The purpose of determining the measurement area is to limit the analysis range, reduce unnecessary calculations, and ensure the accuracy of the analysis. The selection of the measurement area can be determined based on experimental requirements, image quality, and the distribution of interference fringes.

[0092] After determining the measurement area, obtain the baseline within the measurement area, such as Fig.12As shown, the baseline is 150. The baseline can be determined by calculating a specific position of the interference fringes in the initial state. The initial state refers to the state without external interference or change. The specific position can be the center line of the interference fringes, a certain edge line, or an average position line calculated according to a preset mean algorithm. The baseline provides a reference point for the movement of the fringes.

[0093] Next, you need to find the peak of the interference fringe closest to the baseline. The peak is the point where the brightness or contrast in the interference fringe image reaches the maximum, usually corresponding to the alternation of light and dark in the interference fringe. By finding the peak closest to the baseline, you can determine the position of the interference fringe in the current state. The change in the peak position reflects the movement of the interference fringe.

[0094] Finally, based on the peak position found, the moving direction and number of interference fringes can be determined. The moving direction of the interference fringes can be obtained by comparing the difference between the current peak position and the baseline position. If the current peak position moves to the left relative to the baseline, it indicates that the interference fringes move to the left; if the current peak position moves to the right relative to the baseline, it indicates that the interference fringes move to the right. The number of interference fringes is obtained by calculating the number of fringes that differ between the current peak and the baseline. The number of fringes can quantify the degree of movement of the fringes.

[0095] In an optional implementation, determining the stripe movement direction and the number of stripes according to the peak value includes:

[0096] Obtaining a specified number of peaks and calculating the phases of the specified number of peaks, taking one wavelength as a phase interval;

[0097] If the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the left; if the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the right;

[0098] When the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by more than +180 degrees, the number of fringes is increased by 1; when the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by less than -180 degrees, the number of fringes is decreased by 1.

[0099] In order to accurately determine the direction of movement and the number of stripes, it is necessary to obtain a specified number of peaks from the measurement area and calculate the phases of these peaks. Within one wavelength, the phase change is continuous, so the direction of movement of the stripes can be determined by comparing the phase difference between the peak and the reference value. Compare the phase difference between each peak and the reference value (usually a peak position or phase in the initial state). If the phase difference between the current peak and the reference value is reduced relative to the previous peak (that is, the phase rotates counterclockwise, with clockwise as the positive direction), it is determined that the stripes move to the left; if the phase difference between the current peak and the reference value is increased relative to the previous peak (that is, the phase rotates clockwise), it is determined that the stripes move to the right. It should be understood that the direction of change in the phase difference should be opposite to the direction of movement of the stripes, because the change in the phase difference is caused by the movement of the stripes.

[0100] For each peak value obtained, calculate its corresponding phase. Phase is an important parameter to describe the vibration state of light waves. It indicates the offset of the vibration position of light waves at a certain moment relative to the reference point. A complete cycle of interference fringes (i.e., one wavelength) can be regarded as a phase interval, and the phase varies from -180 degrees to +180 degrees within this interval.

[0101] When the phase difference between the first peak position and the reference value in the measurement area shows a sudden change greater than +180 degrees, or less than -180 degrees, it means that the fringe has moved more than half a wavelength, indicating that the number of fringes has changed, so the number of fringes needs to be increased or decreased by 1 (depending on the direction of the sudden change and the convention of fringe movement). The "sudden change" here means that the phase difference suddenly jumps from a value less than +180 degrees (or greater than -180 degrees) to a value greater than +180 degrees (or less than -180 degrees), or vice versa. Specifically, when the phase difference is greater than +180 degrees, the number of fringes is increased by 1; when the phase difference is less than -180 degrees, the number of fringes is decreased by 1.

[0102] In an optional implementation, obtaining the corresponding sensor signal value according to the relationship between the stripe movement information and the sensor signal includes:

[0103] Acquire a standard sensor signal and a standard number of stripes moving under the standard sensor signal;

[0104] The ratio of the standard sensing signal to the standard number of bars is used as a standard sensing coefficient;

[0105] A corresponding sensing signal value is obtained according to the standard sensing coefficient and the number of fringes.

[0106] Through experimental verification, it is found that there is a good linear relationship between temperature change, voltage change, etc. and the number of fringe movements. This means that the change in temperature, voltage, etc. can be indirectly measured by measuring the number of fringe movements. However, due to the influence of various factors (such as thermal expansion of materials, aging of electronic components, etc.), this linear relationship may be disturbed to a certain extent. Therefore, a calibration mechanism needs to be introduced to improve the accuracy of the measurement.

[0107] In order to calibrate the temperature coefficient and voltage coefficient, the number of fringe movements collected by the image sensor can be divided by the temperature change or voltage change. In this way, the temperature change or voltage change corresponding to each fringe movement can be obtained, that is, the temperature coefficient or voltage coefficient. These coefficients reflect the sensitivity of the fiber optic sensor system to temperature changes and voltage changes. By introducing a calibration mechanism for the temperature coefficient and voltage coefficient, the changes in temperature and voltage can be measured more accurately.

[0108] In order to establish the relationship between the fringe movement information and the sensor signal value, it is necessary to know how many interference fringes move under a known or standard sensor signal (i.e., the standard number of fringes). This standard sensor signal can be the output of the sensor under specific conditions, and the standard number of fringes is the number of interference fringes moved under the sensor signal obtained by some method (such as experimental measurement).

[0109] Next, the ratio between the standard sensor signal and the standard number of stripes is calculated to obtain the standard sensor coefficient. The standard sensor coefficient is actually a conversion factor that indicates the number of interference stripes corresponding to each unit sensor signal change, and reflects the sensor signal value change corresponding to the unit stripe movement. The standard sensor coefficient is used to convert the subsequent stripe movement information into the sensor signal value.

[0110] In actual measurement, by obtaining the current number of fringe movements and calculating using the standard sensing coefficient, the corresponding sensor signal value can be obtained. Specifically, the number of fringe movements actually measured is multiplied by the standard sensing coefficient to obtain the sensor signal value corresponding to the fringe movement. This process realizes the conversion from interference fringe images to sensor signal values.

[0111] The sensing signal measurement method provided in the embodiment of the present application uses the above-mentioned optical fiber sensor system to simplify the sensing signal measurement process and improve the measurement efficiency by adjusting the polarization state of the emitted light and collecting the interference fringe image; the peak-finding calculation can accurately obtain the movement information of the interference fringes, thereby improving the measurement accuracy of the sensing signal. By determining the measurement area and obtaining the reference line, the movement information of the interference fringes can be accurately obtained; the movement direction and number of the fringes are determined according to the peak value, reducing the measurement error caused by misjudgment or missed judgment. By obtaining a specified number of peaks and performing phase calculations, the change of the interference fringes can be dynamically monitored, improving the real-time performance of the system; the movement direction and number of the fringes are accurately determined according to the change in the phase difference value, avoiding the measurement error caused by misjudgment or missed judgment. By calculating the standard sensing coefficient and obtaining the sensing signal value according to the number of fringes, the quantitative processing of the sensing signal is realized, and the accuracy and repeatability of the measurement are improved.

[0112] In a high temperature environment, the performance of many optical and electronic components will be affected, and even failures may occur. Therefore, a high temperature warning mechanism is introduced in the fiber optic sensor system. The high temperature warning mechanism monitors the temperature value in real time and compares the real-time monitored temperature value with the preset alarm value. When the real-time monitored temperature value reaches or exceeds the preset alarm value, the fiber optic sensor system will issue an alarm prompt, for example, through sound, light or display screen, etc. to remind the user to pay attention to safety or take corresponding measures.

[0113] An embodiment of the present application further provides a computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, all or part of the steps of the sensor signal measurement method are implemented.

[0114] When the computer program is executed by a processor, the following steps are implemented:

[0115] Performing peak finding calculation on the electrical signal to obtain fringe movement information;

[0116] The corresponding sensor signal value is obtained according to the relationship between the stripe movement information and the sensor signal.

[0117] In an optional embodiment, when the computer program is executed by a processor, the peak finding calculation of the electrical signal is performed to obtain the fringe movement information, specifically including:

[0118] Determine the measurement area;

[0119] Acquiring a baseline within the measurement area;

[0120] Obtaining the peak value closest to the baseline;

[0121] The stripe movement direction and the number of stripes are determined according to the peak value.

[0122] In an optional embodiment, when the computer program is executed by a processor, determining the stripe movement direction and the number of stripes according to the peak value specifically includes:

[0123] Obtaining a specified number of peaks and calculating the phases of the specified number of peaks, taking one wavelength as a phase interval;

[0124] If the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the left; if the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the right;

[0125] When the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by more than +180 degrees, the number of fringes is increased by 1; when the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by less than -180 degrees, the number of fringes is decreased by 1.

[0126] In an optional embodiment, when the computer program is executed by a processor, obtaining a corresponding sensor signal value according to the relationship between the stripe movement information and the sensor signal specifically includes:

[0127] Acquire a standard sensor signal and a standard number of stripes moving under the standard sensor signal;

[0128] The ratio of the standard sensing signal to the standard number of bars is used as a standard sensing coefficient;

[0129] The corresponding sensing signal value is obtained according to the standard sensing coefficient and the number of fringes

[0130] See also Fig.13 , which is a schematic diagram of the structure of a computer device provided in an embodiment of the present application. In a preferred embodiment of the present application, the computer device 13 includes a memory 1301 , at least one processor 1302 , and at least one communication bus 1303 .

[0131] Those skilled in the art should understand that Fig.13 The structure of the computer device shown does not constitute a limitation of the embodiments of the present application. The computer device 13 may also include more or less other hardware or software than shown in the figure, or a different arrangement of components.

[0132] In some embodiments, the computer device 13 is a device that can automatically perform numerical calculations and / or information processing according to pre-set or stored instructions, and its hardware includes but is not limited to microprocessors, application-specific integrated circuits, programmable gate arrays, digital processors, and embedded devices. The computer device 13 may also include client devices, which include but are not limited to any electronic product that can interact with the client through a keyboard, mouse, remote control, touchpad, or voice control device, such as a personal computer, tablet computer, smart phone, digital camera, etc.

[0133] It should be noted that the computer device 13 is only an example, and other existing or future electronic products that are suitable for the present application should also be included in the protection scope of the present application and included here by reference.

[0134] In some embodiments, a computer program is stored in the memory 1301, and when the computer program is executed by the at least one processor 1302, all or part of the steps in the sensor signal measurement method as described are implemented. The memory 1301 includes a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable rewritable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, magnetic disk storage, magnetic tape storage, or any other computer-readable medium that can be used to carry or store data. Further, the computer-readable storage medium may mainly include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application required for at least one function, and the like.

[0135] In some embodiments, the at least one processor 1302 is the control core (Control Unit) of the computer device 13, and uses various interfaces and lines to connect the various components of the entire computer device 13, and executes various functions and processes data of the computer device 13 by running or executing the program or module stored in the memory 1301, and calling the data stored in the memory 1301. For example, when the at least one processor 1302 executes the computer program stored in the memory, it implements all or part of the steps of the sensor signal measurement method described in the embodiment of the present application; or implements all or part of the functions of the sensor signal measurement device. The at least one processor 1302 can be composed of an integrated circuit, for example, it can be composed of a single packaged integrated circuit, or it can be composed of multiple integrated circuits with the same function or different functions, including one or more central processing units (CPU), microprocessors, digital processing chips, graphics processors, and various control chips.

[0136] In some embodiments, the at least one communication bus 1303 is configured to realize connection and communication between the memory 1301 and the at least one processor 1302, etc. Although not shown, the computer device 13 may also include a power supply (such as a battery) for powering each component. Preferably, the power supply may be logically connected to the at least one processor 1302 through a power management device, so as to realize functions such as management of charging, discharging, and power consumption management through the power management device. The power supply may also include any components such as one or more DC or AC power supplies, recharging devices, power failure detection circuits, power converters or inverters, power status indicators, etc. The computer device 13 may also include a variety of sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be repeated here.

[0137] The above-mentioned integrated unit implemented in the form of a software function module can be stored in a computer-readable storage medium. The above-mentioned software function module is stored in a storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a computer device, or a network device, etc.) or a processor to execute part of the method described in each embodiment of the present application.

[0138] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, the division of the modules is only a logical function division, and there may be other division methods in actual implementation.

[0139] The modules described as separate components may or may not be physically separated, and the components shown as modules may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

Claims

1. A fiber optic sensor system, characterized in that: The system comprises: A laser light source, used to generate an optical signal; The optical fiber coupler comprises at least two parallel optical fiber interference arms, which are used to divide the optical signal into at least two beams and make them interfere after propagating along different paths; A polarization controller, arranged at the output end of the optical fiber coupler, for adjusting the polarization state and polarization direction of the output light; A voltage control module, disposed on at least one optical fiber interferometer arm, for changing the phase of the optical fiber by applying voltage; An image sensor, used for collecting interference fringe images and converting the interference fringe images into electrical signals; The data processing device is used to perform peak calculation on the electrical signal to obtain fringe movement information, and obtain a corresponding sensor signal value according to the relationship between the fringe movement information and the sensor signal.

2. The optical fiber sensor system according to claim 1, characterized in that: The polarization controller is used to adjust the 650nm single-mode optical fiber output light to a linear polarization state vibrating in the same direction.

3. The optical fiber sensor system according to claim 2, characterized in that: The polarization controller adjusts the number of turns of the wave plate so that the quarter wave plate is wound once and the half wave plate is wound twice to correspond to the phase delay requirement of the 650nm single-mode optical fiber.

4. The optical fiber sensor system according to any one of claims 1 to 3, characterized in that: The coating layer at the end of the optical fiber is removed, and the optical fibers are placed in a matching glass capillary tube with equal length and in parallel, and are polished through multiple steps to ensure that the output end face is smooth.

5. A method for measuring a sensing signal using an optical fiber sensor system, characterized in that: The method comprises: The light beam of the outgoing light is regulated to be linearly polarized light vibrating in the same direction; Collecting interference fringe images through an image sensor and converting the interference fringe images into electrical signals; The data processing device performs peak search calculation on the electrical signal to obtain fringe movement information, and obtains the corresponding sensor signal value according to the relationship between the fringe movement information and the sensor signal.

6. The sensor signal measurement method according to claim 5, characterized in that: The performing peak finding calculation on the electrical signal to obtain the stripe movement information comprises: Determine the measurement area; Acquiring a baseline within the measurement area; Obtaining the peak value closest to the baseline; The stripe movement direction and the number of stripes are determined according to the peak value.

7. The sensor signal measurement method according to claim 6, characterized in that: Determining the stripe movement direction and the number of stripes according to the peak value comprises: Obtaining a specified number of peaks and calculating the phases of the specified number of peaks, taking one wavelength as a phase interval; If the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the left; if the phase corresponding to the difference between the peak value and the reference value decreases, it is determined that the stripe moves to the right; When the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by more than +180 degrees, the number of fringes is increased by 1; when the phase corresponding to the difference between the first peak position in the measurement area and the reference value changes by less than -180 degrees, the number of fringes is decreased by 1.

8. The sensor signal measurement method according to claim 7, characterized in that: The obtaining of the corresponding sensor signal value according to the relationship between the stripe movement information and the sensor signal comprises: Acquire a standard sensor signal and a standard number of stripes moving under the standard sensor signal; The ratio of the standard sensing signal to the standard number of bars is used as a standard sensing coefficient; A corresponding sensing signal value is obtained according to the standard sensing coefficient and the number of fringes.

9. A computer device, characterized in that: The computer device includes a memory, a processor, and a computer program stored in the memory and executable on the processor, and the processor implements the following steps when executing the computer program: Performing peak-finding calculation on the electrical signal to obtain fringe movement information, wherein the electrical signal is obtained by converting the interference fringe image; The corresponding sensor signal value is obtained according to the relationship between the stripe movement information and the sensor signal.

10. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the following steps are implemented: Performing peak calculation on the electrical signal to obtain fringe movement information, wherein the electrical signal is obtained by converting the interference fringe image; The corresponding sensor signal value is obtained according to the relationship between the stripe movement information and the sensor signal.

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