A physical experimental device and experimental method integrating multiple fiber optic technologies

Abstract

This invention belongs to the field of optical experimental technology, and particularly relates to a physical experimental device and method integrating multiple fiber optic technologies. In use, the light source component emits light waves, which are reflected by the fiber Bragg grating component and split into two parts. One part of the light wave enters the filtering experimental component and then the signal processing module, which processes the signal and displays the results. The other part of the light wave enters the Mach-Zehnder interferometer experimental component and is split into a first light wave and a second light wave. The first light wave passes through the Young's modulus measurement experimental mechanism, and the second light wave passes through the fiber optic temperature sensor experimental mechanism. After exiting the Young's modulus measurement experimental mechanism and the fiber optic temperature sensor experimental mechanism, the first and second light waves couple into the signal processing module, which processes the signal and displays the results. This invention has good integration and can simultaneously measure minute displacements, mechanical parameters, and temperature.

Description

Technical Field

[0001] This invention belongs to the field of optical experimental technology, and in particular relates to a physical experimental device and experimental method that integrates multiple optical fiber technologies. Background Technology

[0002] Fiber optic sensors have broad application prospects in marine science, civil engineering, petrochemicals, aerospace, and other fields. They possess advantages such as electrical insulation, resistance to electromagnetic interference, high sensitivity, high temperature and corrosion resistance, intrinsic safety due to passive sensor terminals, long-distance transmission without signal conversion or amplifiers, and small size and light weight. Fiber optic sensors are broadly classified into functional and transmission-type sensors, including phase-modulated and wavelength-modulated sensors. Phase-modulated fiber optic sensors typically utilize light interference to convert phase changes into light intensity changes to detect external parameters, such as pressure or tension, temperature, etc. A typical example is the fiber Mach-Zehnder interferometer. The most typical wavelength-modulated sensor is the fiber Bragg grating, which is widely used not only in fiber optic communication but also in fiber optic sensing.

[0003] Most existing university optical physics experimental devices can only perform one physics experiment. Different experimental devices are required for different experiments, which is very inconvenient. Therefore, there is an urgent need for a physics experimental device and experimental method that integrates multiple fiber optic technologies. Summary of the Invention

[0004] The purpose of this invention is to provide a physical experimental device and method that integrates multiple fiber optic technologies to solve the above-mentioned problems.

[0005] To achieve the above objectives, the present invention provides the following solution:

[0006] A physical experimental device integrating multiple fiber optic technologies includes:

[0007] The light source module is used to provide a light source;

[0008] An experimental module, connected to the light source module, is used for conducting experiments;

[0009] A signal processing module, connected to the experimental module, is used to receive and process signals emitted by the experimental module and display experimental results.

[0010] The light source module includes a light source component and a fiber Bragg grating component. The experimental module includes a filtering experimental component and a Mach-Zehnder interferometer experimental component. Both the filtering experimental component and the Mach-Zehnder interferometer experimental component are connected to the fiber Bragg grating component. Both the filtering experimental component and the Mach-Zehnder interferometer experimental component are connected to the signal processing module.

[0011] The Mach-Zehnder interferometer experimental assembly includes a Young's modulus measurement experimental mechanism and an optical fiber temperature sensor experimental mechanism.

[0012] Preferably, the light source assembly includes:

[0013] Broadband light source, used to emit light waves;

[0014] An optical power limiter is connected to the broadband light source via an optical fiber, and the optical power limiter is used to stabilize the power of the light wave;

[0015] The optical circulator has an inlet connected to the optical power limiter, a first outlet connected to the fiber Bragg grating assembly via an optical fiber, and a second outlet connected to the filtering experimental assembly and the Mach-Zehnder interferometer experimental assembly via a first optical fiber coupler.

[0016] Preferably, the fiber Bragg grating assembly includes:

[0017] A cantilever beam, one end of which is fixed to the signal processing module by a fixing seat, and the other end of which is suspended in the air;

[0018] A fiber Bragg grating is disposed at the cantilever end of the cantilever beam, and the fiber Bragg grating is connected to one of the outlets of the optical circulator via an optical fiber.

[0019] A micrometer is fixed to the signal processing module, and the cantilever beam extends into the measuring position of the micrometer and abuts against the measuring end of the micrometer.

[0020] Preferably, the filtering experimental components include:

[0021] A wavelength filter is connected to one of the output ports of the first fiber optic coupler via an optical fiber, and the wavelength filter is also connected to the signal processing module via an optical fiber.

[0022] Preferably, the Mach-Zehnder interferometer experimental assembly includes:

[0023] The second fiber optic coupler has an injection port connected to the other injection port of the first fiber optic coupler via an optical fiber, and the second fiber optic coupler has two injection ports.

[0024] The third fiber optic coupler has two injection ports connected to the two injection ports of the second fiber optic coupler via the first interference arm and the second interference arm, respectively. The third fiber optic coupler is connected to the signal processing module via optical fiber.

[0025] Preferably, the Young's modulus measurement experimental mechanism includes:

[0026] Two parallel and symmetrically arranged fixing frames;

[0027] Two vertically arranged columns are respectively fixed to the middle of the top of the two fixed frames;

[0028] A horizontally installed fixing rod is fixed between the tops of the two columns;

[0029] Two vertically arranged guide grooves are respectively opened on the two columns, and the openings of the two guide grooves are arranged opposite to each other;

[0030] Two guide blocks are vertically slidably connected within the two guide grooves, respectively;

[0031] A horizontally positioned movable rod is located directly below the fixed rod, and both ends of the movable rod are fixedly connected to the two guide blocks respectively;

[0032] The weight is detachably connected to the middle of the bottom surface of the movable rod;

[0033] The metal wire is fixed at the middle of the bottom surface of the fixed rod at its top end and fixed at the middle of the top surface of the movable rod at its bottom end.

[0034] The first interference arm is repeatedly moved back and forth between the two columns. The top end of the first interference arm is fixedly connected to the fixed rod, and the bottom end of the first interference arm is fixedly connected to the movable rod.

[0035] Preferably, the fiber optic temperature sensor testing mechanism includes:

[0036] Temperature control box, the second interference arm is inserted inside the temperature control box;

[0037] A temperature controller is electrically connected to the temperature control box, and the temperature controller is located within the signal processing module.

[0038] Preferably, the signal processing module includes:

[0039] The housing, the mounting base, and the micrometer are all fixedly attached to the housing;

[0040] A first photoelectric converter is disposed inside the housing. The first photoelectric converter is connected to the wavelength filter via an optical fiber. The wavelength filter is connected to a first display, which is disposed on the housing.

[0041] A second photoelectric converter is disposed inside the housing. The second photoelectric converter is connected to one outlet of the third fiber optic coupler. The second photoelectric converter is connected to a second display, which is disposed on the housing.

[0042] A third photoelectric converter is disposed within the housing. The third photoelectric converter is connected to another outlet of the third fiber optic coupler. The third photoelectric converter is connected to a third display, which is disposed on the housing.

[0043] An experimental method based on a physical experimental device integrating multiple fiber optic technologies includes the following steps:

[0044] The light source component emits light waves, which are reflected by the fiber Bragg grating component and split into two parts. One part of the light wave enters the filtering experimental component and then enters the signal processing module, which processes the signal and displays the results.

[0045] Another portion of the light wave enters the Mach-Zehnder interferometer experimental assembly and splits into a first light wave and a second light wave. The first light wave passes through the Young's modulus measurement experimental mechanism, and the second light wave passes through the fiber optic temperature sensor experimental mechanism. After exiting the Young's modulus measurement experimental mechanism and the fiber optic temperature sensor experimental mechanism, the first light wave and the second light wave are coupled into the signal processing module, which processes the signal and displays the results.

[0046] Preferably, before performing the Young's modulus experiment, the fiber Bragg grating assembly is adjusted until the signal processing module displays zero. At this time, the wavelength of the incident light wave of the Mach-Zehnder interferometer corresponds to the dark fringes of the Mach-Zehnder interferometer. Then, the Young's modulus experiment is performed through the Young's modulus measurement experimental mechanism.

[0047] Compared with the prior art, the present invention has the following advantages and technical effects:

[0048] In use, the device of this invention emits light waves through a light source assembly. After reflection by a fiber Bragg grating assembly, the light waves are split into two parts. One part enters a filtering experimental assembly and then a signal processing module. The signal processing module processes the signal and displays the results.

[0049] Another portion of the light wave enters the Mach-Zehnder interferometer experimental assembly and splits into a first light wave and a second light wave. The first light wave passes through the Young's modulus measurement experimental mechanism, and the second light wave passes through the fiber optic temperature sensor experimental mechanism. After exiting the Young's modulus measurement experimental mechanism and the fiber optic temperature sensor experimental mechanism, the first and second light waves are coupled into the signal processing module, which processes the signal and displays the results.

[0050] This invention ingeniously integrates multiple related experiments, achieving excellent integration and enabling the simultaneous measurement of minute displacements, mechanical parameters, and temperatures using various optical experiments. This enhances students' knowledge expansion, hands-on skills, and ability to connect and apply knowledge in the new era, broadening their horizons. Attached Figure Description

[0051] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1 This is a schematic diagram of the structure of the present invention;

[0053] Figure 2 For the present invention Figure 1 A partial sectional view of A in the middle;

[0054] Figure 3 For the present invention Figure 1 A magnified view of part B in the image;

[0055] Figure 4 Interference fringes of the second experimental component of the present invention;

[0056] Figure 5 The transmittance of the wavelength filter of this invention varies with wavelength.

[0057] The components include: 1. Broadband light source; 2. Optical power limiter; 3. Optical circulator; 4. First fiber optic coupler; 5. Cantilever beam; 6. Fiber Bragg grating; 7. Mount; 8. Micrometer; 9. Second fiber optic coupler; 10. First interference arm; 11. Mount; 12. Column; 13. Fixed rod; 14. Movable rod; 15. Weight; 16. Second interference arm; 17. Temperature control box; 18. Temperature regulating block; 19. Guide groove; 20. Guide block; 21. Housing; 22. Temperature controller; 23. First photoelectric converter; 24. Second photoelectric converter; 25. Third photoelectric converter; 26. First display; 27. Second display; 28. Third display; 29. ​​Third fiber optic coupler; 30. Wavelength filter. Detailed Implementation

[0058] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0060] Reference Figures 1 to 5 This invention discloses a physical experimental device integrating multiple fiber optic technologies, comprising:

[0061] The light source module is used to provide a light source;

[0062] The experimental module, connected to the light source module, is used for conducting experiments;

[0063] The signal processing module is connected to the experimental module and is used to receive, process, and display the experimental results from the experimental module.

[0064] The light source module includes a light source component and a fiber Bragg grating component. The experimental module includes a filtering experimental component and a Mach-Zehnder interferometer experimental component. Both the filtering experimental component and the Mach-Zehnder interferometer experimental component are connected to the fiber Bragg grating component. Both the filtering experimental component and the Mach-Zehnder interferometer experimental component are connected to the signal processing module.

[0065] The Mach-Zehnder interferometer experimental setup includes a Young's modulus measurement experimental mechanism and an optical fiber temperature sensor experimental mechanism.

[0066] The solution has been further optimized, and the light source components include:

[0067] Broadband light source 1, used to emit light waves;

[0068] Optical power limiter 2 is connected to broadband light source 1 via optical fiber. Optical power limiter 2 is used to stabilize the power of optical waves.

[0069] The optical circulator 3 has an input port connected to the optical power limiter 2. The first output port of the optical circulator 3 is connected to the fiber Bragg grating assembly via optical fiber. The second output port of the optical circulator 3 is connected to the filtering experimental assembly and the Mach-Zehnder interferometer experimental assembly via the first fiber coupler 4.

[0070] The light waves emitted by the broadband light source 1 pass through the optical power limiter 2 and the optical circulator 3 in sequence before entering the fiber Bragg grating assembly. The optical power limiter 2 ensures that the power of each wavelength output by the broadband light source 1 is basically the same, so as to avoid the measurement results being affected by the fluctuation of the light source when the signal is subsequently converted into voltage for demodulation.

[0071] Further optimization of the solution includes the following fiber Bragg grating components:

[0072] Cantilever beam 5, one end of which is fixed to the signal processing module by a fixing seat 7, and the other end of the cantilever beam 5 is suspended in the air;

[0073] The fiber Bragg grating 6 is set at the cantilever end of the cantilever beam 5, and the fiber Bragg grating 6 is connected to one of the emission outlets of the optical circulator 3 through an optical fiber.

[0074] The micrometer 8 is fixed to the signal processing module, and the cantilever beam 5 extends into the measuring position of the micrometer 8 and abuts against the measuring end of the micrometer 8.

[0075] After being reflected by the fiber Bragg grating 6, the light wave returns to the optical circulator 3, exits at another outlet of the optical circulator 3, and enters the first fiber coupler 4.

[0076] The cantilever beam 5 is a metal strip that can produce elastic deformation. The measuring end of the micrometer 8 is a screw. The rotation of the screw drives the cantilever beam 5 to rotate around the fixed base 7. The rotation of the cantilever beam 5 around the fixed base 7 causes the fiber Bragg grating 6 to be stretched, which in turn causes the reflected wavelength to shift.

[0077] One end of the cantilever beam 5 is fixed to the signal processing module via a mounting base 7, which increases the integration of the device.

[0078] Further optimization of the scheme, the filtering experimental components include:

[0079] Wavelength filter 30 is connected to one of the outlets of the first fiber optic coupler 4 via optical fiber, and wavelength filter 30 is also connected to the signal processing module via optical fiber.

[0080] After being reflected by the fiber Bragg grating 6, the light wave returns to the optical circulator 3. At this time, the light wave enters the first fiber coupler 4 through the optical circulator 3. Under the action of the first fiber coupler 4, the light wave is split into two parts. One part of the light wave enters the wavelength filter 30 and drives the cantilever beam 5 to deform through the micrometer 8 screw. The reflected wavelength of the fiber Bragg grating 6 shifts to the longer wavelength direction, so that the transmittance of different reflected wavelengths of the fiber Bragg grating 6 gradually increases after passing through the filter. Then, the signal processing module displays the change in voltage. In this way, the relationship between the displacement of the micrometer 8 screw and the output voltage can be realized, and a displacement measurement experiment can be obtained. This not only satisfies the need to exercise hands-on skills, but also allows learning about the reflection characteristics of the fiber Bragg grating 6 and the relationship with external force or displacement, as well as the characteristics of the wavelength filter 30. This part of the experiment expands the knowledge horizon.

[0081] Further optimization of the scheme, the components of the Mach-Zehnder interferometer experiment include:

[0082] The second fiber optic coupler 9 has an injection port connected to another injection port of the first fiber optic coupler 4 via an optical fiber, and the second fiber optic coupler 9 is provided with two injection ports.

[0083] The third fiber coupler 29 has two injection ports connected to the two injection ports of the second fiber coupler 9 via the first interference arm 10 and the second interference arm 16, respectively. The third fiber coupler 29 is connected to the signal processing module via optical fiber.

[0084] Further optimization of the scheme, the Young's modulus measurement experimental mechanism includes:

[0085] Two parallel and symmetrically arranged fixing frames 11;

[0086] Two vertically arranged columns 12 are respectively fixed to the middle of the top of two fixed frames 11;

[0087] A horizontally installed fixing rod 13 is fixed between the top ends of the two columns 12;

[0088] Two vertically arranged guide grooves 19 are respectively opened on the two columns 12, and the openings of the two guide grooves 19 are arranged opposite each other;

[0089] Two guide blocks 20 are vertically and slidably connected within two guide grooves 19, respectively;

[0090] The horizontally positioned movable rod 14 is located directly below the fixed rod 13, and both ends of the movable rod 14 are fixedly connected to the two guide blocks 20 respectively.

[0091] Weight 15 is detachably connected to the middle of the bottom surface of movable rod 14;

[0092] The metal wire is fixed at the top end to the middle of the bottom surface of the fixed rod 13 and at the bottom end to the middle of the top surface of the movable rod 14.

[0093] The first interference arm 10 is repeatedly positioned between the two columns 12. The top end of the first interference arm 10 is fixedly connected to the fixed rod 13, and the bottom end of the first interference arm 10 is fixedly connected to the movable rod 14.

[0094] The fiber Bragg grating 6 serves as the second light source for the Mach-Zehnder interferometer experimental assembly. By adjusting the wavelength of the light entering the Mach-Zehnder interferometer experimental assembly through the fiber Bragg grating 6, the interference fringes change between adjacent bright and dark fringes when the metal wire is stretched or shortened, resulting in a monotonic change in the output voltage.

[0095] The length of the metal wire is 30cm-100cm;

[0096] By changing the weights 15 of different weights, the movable rod 14 moves along the guide groove 19. This changes the distance between the movable rod 14 and the fixed rod 13, thus changing the length of the metal wire. Simultaneously, the elongation of the first interference arm 10 changes. The repeated back-and-forth movement of the first interference arm 10 transforms the minute changes in the metal wire into a magnified optical quantity. This magnified optical quantity causes the movement of the interference fringes to vary between bright and dark fringes. When the length of the metal wire changes, the interference fringes exhibit... Figure 4The variation in the thick line range shows that the light intensity of the fringes gradually changes between bright and dark areas. The signal processing module measures this change in fringe movement as a simple, intuitive voltage display. Before applying external force to the metal wire to begin measurement, the screw of the micrometer 8 at the suspended end of the metal strip containing the fiber Bragg grating 6 is adjusted, causing the metal strip to bend and deform the fiber Bragg grating 6. At this point, the wavelength incident on the Mach-Zehnder interferometer component changes accordingly until the voltage display shows 0 volts. The incident wavelength at this moment corresponds to the dark fringes of the Mach-Zehnder interferometer component. Subsequently, the external force on the metal wire is gradually increased, and the corresponding values ​​are measured. The voltage (which gradually increases with the increase of external force) is measured, and then the external force on the metal wire is gradually reduced at the same external force interval, and the corresponding voltage is measured (which gradually decreases with the decrease of external force) until it decreases to about 0 volts (considering that the metal wire may not be able to completely return to its original state, so 0 volts may not necessarily appear during the process of reducing the external force at the same external force interval). When the external force (weight 15) loaded on the metal wire is increased or decreased, the output voltage is a unidirectional change that gradually increases or decreases. Based on the applied external force and the corresponding measured quantity, the length and diameter parameters of the metal wire, the Young's modulus to be measured can be obtained using the conventional Young's modulus formula. By using the Young's modulus measurement experimental setup of the Mach-Zehnder interferometer experimental assembly, we can master the application of optical amplification methods to solve practical problems. At the same time, we can transform the demodulation difficulty of minute signal changes into the identification of light intensity changes between dark and bright fringes, and learn the problem-solving mindset of simplifying difficult problems. By using fiber Bragg grating components to change the input wavelength of the Mach-Zehnder interferometer experimental assembly, the interferometer has a minimum output of 0 when the external parameters such as Young's modulus are in the initial state. When the external environmental parameters change slightly, the output voltage of the interferometer changes accordingly, thereby achieving demodulation of interference signals with minute parameter changes and obtaining high-sensitivity measurements of the Mach-Zehnder interferometer experimental assembly.

[0097] Further optimization of the scheme, the fiber optic temperature sensor test mechanism includes:

[0098] Temperature control box 17, the second interference arm 16 is installed inside temperature control box 17;

[0099] Temperature controller 22 is electrically connected to temperature control box 17 and is located in signal processing module.

[0100] Another portion of the light wave emitted by the second fiber coupler 9 passes through the second interferometer arm 16, which is wound around a temperature regulating block 18 inside the temperature control box 17. The temperature regulating block 18 is a semiconductor with the Peltier effect. The current direction of the temperature regulating block 18 is changed by the temperature controller 22 to heat or cool the optical fiber, causing the optical path of the second interferometer arm 16 inside the temperature control box 17 to change. The interference fringes of the Mach-Zehnder interferometer experimental assembly move accordingly. A signal processing module is connected to one of the output terminals of the Mach-Zehnder interferometer experimental assembly to realize the experiment of the fiber optic temperature sensor.

[0101] The second interferometer arm 16 and the first interferometer arm 10 of the Mach-Zehnder interferometer experimental assembly introduce two experiments respectively. This not only satisfies the need for hands-on practice but also allows students to learn how the optical path difference of the Mach-Zehnder interferometer is affected by environmental interference, causing the interference fringes to shift. The amount of fringe shift can be used to detect the gradual change in light intensity during the change of dark and bright fringes, thus measuring minute changes in external parameters. It can also be used to detect changes in external environmental parameters by detecting the number of fringe shifts. Through a fiber optic Mach-Zehnder interferometer, students can deepen their understanding of the interference principle and master the demodulation methods of different interference signals, thus elevating their ability to apply theoretical knowledge to solve practical problems.

[0102] Further optimization of the solution includes the following signal processing module:

[0103] The housing 21, the mounting base 7, and the micrometer 8 are all fixedly connected to the housing 21;

[0104] The first photoelectric converter 23 is disposed inside the housing 21. The first photoelectric converter 23 is connected to the wavelength filter 30 via an optical fiber. The wavelength filter 30 is connected to the first display 26, which is disposed on the housing 21.

[0105] The second photoelectric converter 24 is disposed inside the housing 21. The second photoelectric converter 24 is connected to one of the outlets of the third fiber optic coupler 29. The second photoelectric converter 24 is connected to a second display 27, which is disposed on the housing 21.

[0106] The third photoelectric converter 25 is disposed inside the housing 21. The third photoelectric converter 25 is connected to another outlet of the third fiber optic coupler 29. The third photoelectric converter 25 is connected to the third display 28, which is disposed on the housing 21.

[0107] An experimental method for a physical experimental device integrating multiple fiber optic technologies includes the following steps:

[0108] The light source component emits light waves, which are reflected by the fiber Bragg grating component and split into two parts. One part of the light wave enters the filtering experimental component and then enters the signal processing module. The signal processing module processes the signal and displays the results.

[0109] Another portion of the light wave enters the Mach-Zehnder interferometer experimental assembly and splits into a first light wave and a second light wave. The first light wave passes through the Young's modulus measurement experimental mechanism, and the second light wave passes through the fiber optic temperature sensor experimental mechanism. After exiting the Young's modulus measurement experimental mechanism and the fiber optic temperature sensor experimental mechanism, the first and second light waves are coupled into the signal processing module, which processes the signal and displays the results.

[0110] To further optimize the scheme, before conducting the Young's modulus experiment, the fiber Bragg grating assembly is adjusted until the signal processing module display is zero. At this time, the wavelength of the incident light wave of the Mach-Zehnder interferometer assembly corresponds to the dark fringe of the Mach-Zehnder interferometer assembly. Then, the Young's modulus experiment is conducted through the Young's modulus measurement experimental mechanism.

[0111] Specific experimental steps:

[0112] The light wave emitted by the broadband light source 1 passes sequentially through one exit end of the optical power limiter 2 and the optical circulator 3, then enters the fiber Bragg grating 6. After being reflected by the fiber Bragg grating 6, it returns to the optical circulator 3, and enters the first fiber coupler 4 through the other exit end of the optical circulator 3. Under the action of the first fiber coupler 4, the light wave is split into two parts. One part enters the wavelength filter 30, and the characteristics of the wavelength filter 30 are as follows: Figure 5 As shown, resembling an inverted parabola, the transmittance gradually decreases to a minimum and then gradually increases again as the wavelength increases. The reflected wavelength of the fiber Bragg grating 6 is limited to the range where the transmittance of the wavelength filter 30 increases. The design is such that when the cantilever beam 5 of the fiber Bragg grating 6 is naturally suspended, the reflected wavelength is at a short wavelength position. As the screw of the micrometer 8 pushes the cantilever beam 5 to completely deform, the reflected wavelength of the fiber Bragg grating 6 shifts to the long wavelength direction. This causes the transmittance of different reflected wavelengths of the fiber Bragg grating 6 to gradually increase after passing through the filter. Then, the output of the first photoelectric converter 23 and the first display 26 is the change in voltage magnitude. In this way, the relationship between the displacement of the screw of the micrometer 8 and the output voltage can be realized, resulting in a displacement measurement experiment. This not only satisfies the need for hands-on practice but also allows students to learn about the relationship between the reflection characteristics of the fiber Bragg grating 6 and external force or displacement, as well as the characteristics of the wavelength filter. This part of the experiment expands their knowledge horizon.

[0113] Another portion of the light wave enters the second fiber coupler 9 and is split into a first light wave and a second light wave under the action of the second fiber coupler 9. The second light wave passes through the second interference arm 16, which is wrapped around the temperature regulating block 18 in the temperature control box 17. The temperature of the temperature regulating block 18 is adjusted by the temperature controller 22 to raise or lower the temperature of the second interference arm 16. The raising or lowering of the temperature causes the optical path of the second interference arm 16 in the temperature control box 17 to change, and the interference fringes generated by the Mach-Zehnder interference experimental assembly move accordingly. At this time, the second photoelectric converter 24 converts the optical signal output from one of the output ports of the third fiber coupler 29 into an electrical signal and displays it on the second display 27 (preferably a fringe counter), thus realizing the experiment of the fiber optic temperature sensor.

[0114] The first light wave passes through the first interferometer arm 10. By changing the weight 15 at the bottom of the movable rod 14, the movable rod 14 moves along the guide groove 19. At this time, the distance between the movable rod 14 and the fixed rod 13 changes, which in turn changes the length of the metal wire. Simultaneously, the elongation of the first interferometer arm 10 changes. The function of the first interferometer arm 10 repeatedly moving back and forth is to convert the minute changes in the metal wire into a magnified optical quantity. The magnified optical quantity causes the movement of the interference fringes to change between bright and dark fringes. When the length of the metal wire changes, the interference fringes appear as follows: Figure 4The variation in the thick line range shows that the light intensity of the fringes gradually changes between bright and dark. The optical signal from the other output end of the third fiber coupler 29 is converted into an electrical signal by the third photoelectric converter 25 and displayed on the third display 28. The measurement of the fringe movement information is designed as a simple and intuitive voltage display. Before applying external force to the metal wire to start the measurement, the screw of the micrometer 8 at the suspended end of the metal strip where the fiber Bragg grating 6 is located is adjusted to cause the metal strip to bend and deform the fiber Bragg grating 6. At this time, the wavelength incident on the Mach-Zehnder interferometer experimental component changes accordingly until the voltage display shows 0 volts. At this moment, the incident wavelength of the Mach-Zehnder interferometer experimental component corresponds to the dark wavelength of the Mach-Zehnder interferometer experimental component. Stripes; then gradually increase the external force on the metal wire and measure the corresponding voltage (the voltage gradually increases with the increase of the external force), and then gradually decrease the external force on the metal wire at the same external force interval and measure the corresponding voltage (the voltage gradually decreases with the decrease of the external force) until it decreases to about 0 volts (considering that the metal wire under test may not be able to completely return to its original state, so 0 volts may not necessarily appear during the process of decreasing the external force at the same external force interval). When increasing or decreasing the external force (weight 15) on the metal wire, the output voltage is a unidirectional change of gradually increasing or gradually decreasing; according to the applied external force and the corresponding measured quantity, the length and diameter parameters of the metal wire, the Young's modulus to be measured can be obtained using the conventional Young's modulus formula. By using the Young's modulus measurement experimental setup of the Mach-Zehnder interferometer experimental assembly, we can master the application of optical amplification methods to solve practical problems. At the same time, we can transform the demodulation difficulty of minute signal changes into the identification of light intensity changes between dark and bright fringes, and learn the problem-solving mindset of simplifying difficult problems. By using fiber Bragg grating components to change the input wavelength of the Mach-Zehnder interferometer experimental assembly, the interferometer has a minimum output of 0 when the external parameters such as Young's modulus are in the initial state. When the external environmental parameters change slightly, the output voltage of the interferometer changes accordingly, thereby achieving demodulation of interference signals with minute parameter changes and obtaining high-sensitivity measurements of the Mach-Zehnder interferometer experimental assembly.

[0115] The second interferometer arm 16 and the first interferometer arm 10 of the Mach-Zehnder interferometer experimental assembly introduce two experiments respectively. This not only satisfies the need for hands-on practice but also allows students to learn how the optical path difference of the Mach-Zehnder interferometer is affected by environmental interference, causing the interference fringes to shift. The amount of fringe shift can be used to detect the gradual change in light intensity during the change of dark and bright fringes, thus measuring minute changes in external parameters. It can also be used to detect changes in external environmental parameters by detecting the number of fringe shifts. Through a fiber optic Mach-Zehnder interferometer, students can deepen their understanding of the interference principle and master the demodulation methods of different interference signals, thus elevating their ability to apply theoretical knowledge to solve practical problems.

[0116] This invention integrates experiments from multiple disciplines, including the mechanics of Young's modulus, fringe counting and measurement of minute fringe changes in Mach-Zehnder interferometry to achieve the required physical quantity measurement, displacement sensing using fiber Bragg gratings 6, the working principle of optical circulators 3, and fiber optic technology, into a single experimental device. This up-to-date approach addresses the challenges of knowledge expansion and hands-on skill enhancement for students in the new era, while also broadening their horizons. Furthermore, regarding the demodulation of Mach-Zehnder interferometry signals, this invention cleverly alters the input wavelength of the Mach-Zehnder interferometer while increasing experimental training content. This results in a minimum output value for the interferometer in its initial state, while the output voltage changes accordingly with minute variations in environmental parameters, simplifying signal demodulation and demonstrating good practicality.

[0117] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0118] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A physical experiment apparatus that integrates a plurality of optical fiber technologies, characterized by, include: The light source module is used to provide a light source; An experimental module, connected to the light source module, is used for conducting experiments; A signal processing module, connected to the experimental module, is used to receive and process signals emitted by the experimental module and display experimental results. The light source module includes a light source component and a fiber Bragg grating component. The experimental module includes a filtering experimental component and a Mach-Zehnder interferometer experimental component. Both the filtering experimental component and the Mach-Zehnder interferometer experimental component are connected to the fiber Bragg grating component. Both the filtering experimental component and the Mach-Zehnder interferometer experimental component are connected to the signal processing module. The Mach-Zehnder interferometer experimental assembly includes a Young's modulus measurement experimental mechanism and an optical fiber temperature sensor experimental mechanism. The Mach-Zehnder interferometer experimental assembly also includes a first interferometer arm (10) and a second interferometer arm (16). The first interferometer arm (10) passes through the Young's modulus measurement experimental mechanism, and the second interferometer arm (16) passes through the fiber optic temperature sensor experimental mechanism. The Young's modulus measurement experimental mechanism includes: Two parallel and symmetrically arranged fixing frames (11); Two vertically arranged columns (12) are respectively fixed to the middle of the top of the two fixed frames (11); A horizontally positioned fixing rod (13) is fixed between the top ends of the two columns (12); Two vertically arranged guide grooves (19) are respectively opened on the two columns (12), and the openings of the two guide grooves (19) are arranged opposite to each other; Two guide blocks (20) are vertically slidably connected in the two guide grooves (19); A horizontally positioned movable rod (14) is located directly below the fixed rod (13), and both ends of the movable rod (14) are respectively fixed to the two guide blocks (20); The weight (15) is detachably connected to the middle of the bottom surface of the movable rod (14); The metal wire is fixed at the top end to the middle of the bottom surface of the fixed rod (13) and at the bottom end to the middle of the top surface of the movable rod (14). The first interference arm (10) is repeatedly positioned between the two columns (12). The top end of the first interference arm (10) is fixed to the fixed rod (13), and the bottom end of the first interference arm (10) is fixed to the movable rod (14).

2. The physical experiment device integrating multiple optical fiber technologies according to claim 1, wherein, The light source assembly includes: Broadband light source (1) is used to emit light waves; An optical power limiter (2) is connected to the broadband light source (1) via an optical fiber. The optical power limiter (2) is used to stabilize the power of the light wave. The optical circulator (3) has an entrance port connected to the optical power limiter (2). The first exit port of the optical circulator (3) is connected to the fiber Bragg grating assembly via an optical fiber. The second exit port of the optical circulator (3) is connected to the filtering experimental assembly and the Mach-Zehnder interferometer experimental assembly via a first fiber coupler (4).

3. The physical experiment apparatus of claim 2, wherein The fiber Bragg grating assembly includes: A cantilever beam (5), one end of which is fixed to the signal processing module by a fixing seat (7), and the other end of which is suspended in the air; A fiber Bragg grating (6) is disposed at the suspended end of the cantilever beam (5), and the fiber Bragg grating (6) is connected to one of the outlets of the optical circulator (3) via an optical fiber. The micrometer (8) is fixed to the signal processing module, and the suspended end of the cantilever beam (5) extends into the measuring position of the micrometer (8) and abuts against the measuring end of the micrometer (8).

4. The physical experiment apparatus of claim 3, wherein The filtering experimental components include: The wavelength filter (30) is connected to one of the outlets of the first fiber coupler (4) via an optical fiber, and the wavelength filter (30) is connected to the signal processing module via an optical fiber.

5. The physical experiment apparatus of claim 4, wherein The Mach-Zehnder interferometer experimental components include: The second fiber optic coupler (9) has an injection port connected to another injection port of the first fiber optic coupler (4) via an optical fiber, and the second fiber optic coupler (9) has two injection ports; The third fiber coupler (29) has two injection ports connected to the two injection ports of the second fiber coupler (9) via the first interference arm (10) and the second interference arm (16), respectively. The third fiber coupler (29) is connected to the signal processing module via optical fiber.

6. The physical experiment apparatus of claim 5, wherein The fiber optic temperature sensor testing mechanism includes: Temperature control box (17), the second interference arm (16) is inserted inside the temperature control box (17); Temperature controller (22) is electrically connected to the temperature control box (17), and the temperature controller (22) is located in the signal processing module.

7. A physical experimental apparatus integrating multiple fiber optic technologies according to claim 5, characterized in that, The signal processing module includes: The housing (21), the mounting base (7), and the micrometer (8) are all fixed to the housing (21); A first photoelectric converter (23) is disposed inside the housing (21). The first photoelectric converter (23) is connected to the wavelength filter (30) via an optical fiber. The wavelength filter (30) is connected to a first display (26). The first display (26) is disposed on the housing (21). The second photoelectric converter (24) is disposed inside the housing (21). The second photoelectric converter (24) is connected to one outlet of the third fiber optic coupler (29). The second photoelectric converter (24) is connected to a second display (27), which is disposed on the housing (21). A third photoelectric converter (25) is disposed inside the housing (21). The third photoelectric converter (25) is connected to another outlet of the third fiber optic coupler (29). The third photoelectric converter (25) is connected to a third display (28), which is disposed on the housing (21).

8. An experimental method based on a physical experimental apparatus integrating multiple fiber optic technologies as described in any one of claims 1-7, characterized in that, Includes the following steps: The light source component emits light waves, which are reflected by the fiber Bragg grating component and split into two parts. One part of the light wave enters the filtering experimental component and then enters the signal processing module, which processes the signal and displays the results. Another portion of the light wave enters the Mach-Zehnder interferometer experimental assembly and splits into a first light wave and a second light wave. The first light wave passes through the Young's modulus measurement experimental mechanism, and the second light wave passes through the fiber optic temperature sensor experimental mechanism. After exiting the Young's modulus measurement experimental mechanism and the fiber optic temperature sensor experimental mechanism, the first light wave and the second light wave are coupled into the signal processing module, which processes the signal and displays the results.

9. The experimental method according to claim 8, characterized in that, Before conducting the Young's modulus experiment, the fiber Bragg grating assembly is adjusted until the signal processing module displays zero. At this time, the wavelength of the incident light wave of the Mach-Zehnder interferometer corresponds to the dark fringes of the Mach-Zehnder interferometer. Then, the Young's modulus experiment is conducted through the Young's modulus measurement experimental mechanism.

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