Temperature and sound pressure double-parameter measuring device and measuring method based on fluorescence sensing

Abstract

The invention discloses a temperature and sound pressure double-parameter measuring device and method based on fluorescence sensing, and the device comprises a light source driving module which is used for outputting pulsed light and exciting a fluorescent material to emit light; the optical fiber fluorescence sensor is used for detecting changes of temperature and sound pressure; after the fluorescence signal detection circuit receives the fluorescence signal transmitted by the optical fiber fluorescence sensor, a photoelectric conversion circuit converts the fluorescence signal into an electric signal and processes the electric signal to obtain a filtered and amplified signal; and the signal demodulation processing circuit is used for processing the fluorescence signal output by the fluorescence detection circuit to obtain the fluorescence lifetime. According to the temperature and sound pressure double-parameter measuring device based on fluorescence sensing, the optical fiber fluorescence sensor which is simple in structure and high in sensitivity is designed, and measurement of the temperature and sound pressure double parameters is achieved.

Description

Technical Field

[0001] This invention belongs to the field of fiber optic sensing technology, specifically relating to a dual-parameter measurement device and method for temperature and sound pressure based on fluorescence sensing. Background Technology

[0002] Fiber optic sensors are widely used in the detection of physical quantities such as temperature, pressure, and sound waves due to their advantages of resistance to electromagnetic interference, small size, and high sensitivity. However, most existing fiber optic sensors only measure a single physical quantity, such as temperature sensors based on Bragg gratings or Raman scattering, or pressure sensors based on fiber optic interferometers. These single-parameter sensors are susceptible to interference from other physical quantities in complex environments, leading to measurement errors. For example, temperature changes may cause substrate drift in sound pressure sensors, while sound pressure fluctuations may also affect temperature readings through fiber optic mechanical deformation, creating a cross-sensitivity problem.

[0003] To address the challenge of simultaneous measurement of multiple parameters, some studies have attempted to combine various sensing mechanisms, such as multi-core optical fibers or composite grating structures. However, these approaches suffer from drawbacks such as system complexity, demodulation difficulties, and high costs. Furthermore, while fluorescence sensing technology can reflect environmental changes through fluorescence lifetime or intensity, the response of a single fluorescence parameter (such as lifetime) to multiple physical quantities exhibits coupling, making it difficult to distinguish the independent effects of temperature and sound pressure. For instance, existing fluorescence sensors typically only utilize the temperature dependence of fluorescence lifetime, neglecting the influence of sound pressure on fluorescence characteristics, or lack effective decoupling models, thus limiting the accuracy of dual-parameter measurements. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a simple and highly sensitive dual-parameter measurement device and method based on fluorescence sensing, which can realize the measurement of both temperature and sound pressure, and analyze the changes in fluorescence intensity and fluorescence lifetime caused by sound pressure, thus solving the problem of cross-sensitivity between temperature and sound pressure.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing, characterized in that it comprises: The excitation light output module is used to output the excitation light signal that excites the fluorescent material to generate a fluorescence signal; The fiber optic fluorescence sensing probe generates a fluorescence signal under the excitation of the excitation light signal output by the optical pulse output module. A sound pressure measuring device is used to measure the fluorescence signal generated by the fiber optic fluorescence sensing probe under different sound pressures at a constant temperature. A temperature measuring device is used to measure the fluorescence signal generated by the fiber optic fluorescence sensing probe at different temperatures when the sound pressure level is constant. A filter is used to filter out the excitation light signal mixed in with the fluorescence signal and stray light in the system's optical path; The signal detection module receives the fluorescence signal transmitted through the filter and converts the fluorescence signal into an electrical signal; The signal processing module obtains the fluorescence lifetime at different temperatures and sound pressures based on the electrical signal converted by the signal detection module; and obtains the temperature and sound pressure to be monitored based on the fluorescence lifetime at different temperatures and sound pressures.

[0006] The light source output module consists of a signal generator and a voltage-to-current conversion integrated module. The signal generator generates an electrical pulse signal with a predetermined frequency and pulse width. The voltage-to-current conversion integrated module converts the voltage signal generated by the signal generator into a current signal to drive the laser diode to output a corresponding optical pulse signal, thereby exciting the fluorescent material to generate a fluorescent signal.

[0007] Fiber optic fluorescence sensing probes are used to measure the sensitivity of fluorescent materials to temperature and stress, including temperature and sound pressure. Excitation light from the light source driving module is transmitted through a multimode fiber to excite the fluorescent material to emit light. When the excitation light disappears, the fluorescent material produces a fluorescence afterglow signal, which is then output.

[0008] The signal detection module consists of a photodetector and an oscilloscope. After receiving the fluorescence signal transmitted through the filter, the photodetector converts the fluorescence signal into an electrical signal through a photoelectric conversion circuit to obtain a fluorescence digital signal and outputs it. The complete waveform of the fluorescence signal can be observed by receiving it with the oscilloscope.

[0009] This invention proposes a fiber optic fluorescence sensing probe based on dual-parameter measurement of temperature and sound pressure, the fabrication method of which is as follows: Using the MMF-MMF cladding alignment mode of a conventional fusion splicer, and after adjusting parameters such as discharge power and discharge time, a multimode fiber with a core diameter of 62.5 μm and a cladding diameter of 125 μm was fused to both ends of a hollow-core photonic crystal fiber with a core diameter of 16 μm and a cladding diameter of 125 μm. Then, rare-earth fluoride powder ZnOF:Yb was applied. 3+ Er 3+ After mixing with NOA61 optical adhesive at a 1:1 ratio, the mixture is evenly applied to the cladding of the hollow photonic crystal fiber after the coating layer has been removed, and then cured with a 365nm UV lamp. The fabricated MMF-PCF-MMF sensor structure is placed on a steel base under a certain stress, and then a small amount of polyester adhesive is dropped onto the contact area between the base and the sensor to facilitate the loading of acoustic signals onto the sensor.

[0010] This invention also provides a fiber optic fluorescence sensing detection method based on dual-parameter measurement of temperature and sound pressure, comprising: During temperature measurement, the fiber optic fluorescence sensing probe is placed on a digital display constant-temperature heating stage. While maintaining a relatively stable sound pressure level, the fluorescence signal at different temperatures can be detected by controlling the temperature reading of the stage. The corresponding fluorescence lifetime is then obtained through data processing. Utilizing the sensitivity of fluorescence lifetime and fluorescence intensity to temperature, linear relationships between fluorescence lifetime and temperature, as well as between fluorescence intensity and temperature, can be fitted, and the sensitivity of each curve can be obtained.

[0011] During sound pressure level (SPL) measurement, the fiber optic fluorescence sensor probe is placed on a digitally displayed constant-temperature heating platform. While maintaining a relatively stable temperature, the SPL of the audio transmitter is varied by controlling its frequency to a constant level, allowing the detection of fluorescence signals at different SPL levels. The output SPL level can be calibrated using a sound pressure meter, and the corresponding SPL can be calculated using the SPL formula. Data processing then yields the corresponding fluorescence lifetime. Utilizing the sensitivity of fluorescence lifetime and fluorescence intensity to SPL, linear relationships between fluorescence lifetime and SPL, as well as between fluorescence intensity and SPL, can be fitted, and the sensitivity of each curve can be obtained.

[0012] Since both fluorescence lifetime and fluorescence intensity are sensitive to temperature and sound pressure, fiber optic fluorescence sensing devices based on dual-parameter measurement of temperature and sound pressure will have cross-sensitivity when performing dual-parameter sensing of temperature and sound pressure. This invention uses a sensitivity matrix to eliminate the cross-sensitivity caused by temperature and sound pressure.

[0013] Compared with the prior art, the advantages of the present invention are: This invention proposes a dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing. It utilizes the dual sensitivity of rare-earth-doped fluorescent materials to both temperature and sound pressure, combined with a composite structure of multimode fiber and hollow-core photonic crystal fiber, to achieve efficient signal transmission and sensing. Simultaneously, by constructing a sensitivity matrix model, the changes in fluorescence lifetime and intensity are transformed into independent solutions for temperature and sound pressure, effectively eliminating cross-sensitivity issues. Compared to traditional single-parameter sensors or complex multi-parameter systems, this invention offers advantages such as simplified structure, high sensitivity, and strong anti-interference capability, providing a new technical path for real-time dual-parameter monitoring. Attached Figure Description

[0014] Figure 1 This is a system connection diagram of the present invention; Figure 2 This is a schematic diagram of the sensor probe structure of the present invention; Figure 3 This is a schematic diagram of the fluorescence lifetime versus temperature fitting curve of the present invention; Figure 4 This is a schematic diagram of the fitting curve of fluorescence peak intensity versus temperature in this invention; Figure 5This is a schematic diagram of the fluorescence lifetime fitting curve as a function of sound pressure in this invention; Figure 6 This is a schematic diagram of the fitting curve of fluorescence peak intensity as a function of sound pressure in this invention; Detailed Implementation

[0015] The present invention will be described in detail below with reference to the accompanying drawings, but this should not be construed as limiting the scope of protection of the present invention.

[0016] like Figure 1 As shown, the present invention provides a dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing, comprising: 1. Signal generator, 2. Voltage-to-current integrated module, 3. Laser diode, 4. Fiber optic fluorescence sensor probe, 5. Filter, 6. Photodetector, 7. Oscilloscope, 8. Host computer software, 9. Digital display constant temperature heating platform, 10. Audio transmitter and 11. Sound pressure meter. The output of signal generator 1 is connected to the input of voltage-to-current integrated module 2, and laser diode 3 is connected to the output of voltage-to-current integrated circuit 2 to modulate the pulsed excitation light required by the system. The excitation light signal is transmitted to fiber optic fluorescence sensing probe 4 via multimode fiber, stimulating the fluorescent material on the sensor to emit light. Fiber optic fluorescence sensing probe 4 is fixed with fiber optic jumper clamps and subjected to a certain stress on a digital display constant temperature heating platform 9. Audio transmitter 10 and sound pressure meter 11 are placed on both sides of the sensing probe, respectively. Fluorescence signals generated at different temperatures or sound pressures are transmitted to filter 5 via multimode fiber. After the excitation light and stray light from the system optical path are filtered out by filter 5, the fluorescence signal is converted into an electrical signal by photodetector 6. The fluorescence digital signal output by photodetector 6 is received by oscilloscope 7, allowing observation of the complete waveform of the fluorescence signal. Finally, the host computer software processes the signal to obtain the fluorescence lifetime at different temperatures or sound pressures. The fluorescent material selected in this invention is rare earth fluoride powder ZnOF:Yb. 3+ Er 3+ It can display red light under far-infrared light illumination of 940nm~1060nm (peak at 980nm) and 1550nm.

[0017] Based on the selected fluorescent material, the laser to be used is a 980nm wavelength laser diode with a pigtail, the pigtail being a multimode fiber with a core of 62.5um and a cladding of 125um, and a maximum output power of 30mw.

[0018] Since the fluorescence emission band of this system is the red light band between 640nm and 680nm, the selected filter must be able to pass fluorescence in this band but not excitation light at 980nm. Finally, a narrow bandpass filter with a center wavelength of 660nm and a bandwidth of 30nm was selected.

[0019] The photodetector selected in this invention is a silicon photodiode with an FC interface package on the photosensitive surface, and the response wavelength is between 400nm and 1100nm. The advantage of this type of detector packaging is that the diameter and thickness of the filter can be cut according to the size of the package, the filter can be attached close to the photosensitive surface of the detector, and then packaged, so that the photodetector can be directly coupled to the optical fiber without the need for a lens or optical fiber collimator.

[0020] like Figure 2 The diagram shows the sensor probe structure of this invention. The fabrication method of the fiber optic fluorescent sensor probe involves using the MMF-MMF cladding alignment mode of a conventional fusion splicer. After adjusting parameters such as discharge power and discharge time, the two ends of a hollow photonic crystal fiber (PCF) are fused with a multimode fiber (MMF). Then, a 1:1 mixture of fluorescent material and NOA61 optical adhesive is uniformly applied to the cladding of the hollow photonic crystal fiber after the coating layer has been removed, and cured using a 365nm UV lamp. The fabricated MMF-PCF-MMF sensor structure is placed on a steel base under certain stress. A small amount of polyester adhesive is then applied to the contact area between the base and the sensor to facilitate the loading of an acoustic signal onto the sensor.

[0021] The fiber optic fluorescence sensor probe is fixed with a fiber optic jumper clamp and subjected to a certain stress on a digitally displayed constant-temperature heating platform. While maintaining a relatively stable temperature, the fluorescence signal at different sound pressure levels can be detected by controlling the frequency of the audio transmitter to a constant value and changing the sound pressure level of the transmitter. The output sound pressure level can be calibrated using a sound pressure meter, and the corresponding sound pressure can be calculated using the sound pressure level formula. The corresponding fluorescence lifetime is then obtained through data processing. Utilizing the sensitivity of fluorescence lifetime and fluorescence intensity to sound pressure, linear relationships between fluorescence lifetime and sound pressure, as well as between fluorescence intensity and sound pressure, can be fitted, and the sensitivity of each curve can be obtained.

[0022] With a constant sound pressure level, adjusting the temperature of the digital display constant-temperature heating stage allows for the acquisition of the sensor's fluorescence signal at each stable temperature point. Data processing yields the corresponding fluorescence lifetime and fluorescence intensity. Based on the one-to-one correspondence between fluorescence lifetime, fluorescence intensity, and temperature, the fluorescence lifetime is fitted. With temperature linear curve and fluorescence peak intensity With temperature The linear relationship curve.

[0023] When the temperature remains constant, adjusting the sound pressure signal of the audio transmitter allows for the acquisition of the sensor's fluorescence signal at each stable sound pressure level. Data processing yields the corresponding fluorescence lifetime and fluorescence intensity. Based on the one-to-one correspondence between fluorescence lifetime, fluorescence intensity, and sound pressure, the fluorescence lifetime is then fitted. With sound pressure linear curve and fluorescence peak intensity With sound pressure The linear relationship curve.

[0024] Example 1: This embodiment provides a dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing.

[0025] A signal generator and a voltage-to-current converter integrated module together form the excitation light driving module. A pulsed square wave signal with a duty cycle of 50% and a frequency of 500Hz is applied to the signal generator. After passing through the voltage-to-current converter integrated module, it drives the laser diode to generate pulsed excitation light with a center wavelength of 980nm and an output power of approximately 10mW. The excitation light is transmitted to a fiber optic fluorescence sensing probe via a multimode fiber, exciting the fluorescent material on the sensing probe to emit a fluorescence signal with a peak wavelength of 665nm.

[0026] The fiber optic fluorescence sensor probe was placed on a digital display constant-temperature heating stage. Without loading any acoustic signal, the ambient sound pressure level was measured to be 0.00399 Pa using a sound pressure meter. Maintaining a relatively stable sound pressure level, the fluorescence signal at different temperatures could be detected by controlling the temperature reading of the digital display heating stage. The generated fluorescence signal was transmitted via a multimode fiber to a filter. After the filter removed the 980nm excitation light and stray light from the system's optical path, the fluorescence signal was received by a photodetector and converted into an electrical signal. Data processing was then performed to obtain the corresponding fluorescence lifetime.

[0027] The acquired fluorescence signal was subjected to Discrete Fourier Transform (DFT) using the Fourier Transform method, and the fluorescence lifetime was calculated by taking the phase tangent of the first term after the transform. .

[0028] Fluorescence signals at equal intervals After sampling, it can be written as:

[0029] in, Fluorescence intensity The initial fluorescence intensity, The number of sampling points. The data sampling time interval, DC bias; Performing a Fourier transform on the above equation yields:

[0030] in, , .

[0031] when At that time, we can obtain:

[0032] As can be seen from the above formula, Term and DC bias Since this is not relevant, this item will not be selected for fluorescence lifetime calculation.

[0033] when At that time, we can obtain:

[0034] As can be seen from the above formula, Term and DC bias Irrelevant. The phase angle tangent of the term is:

[0035] in, Represents a term of degree 1 The imaginary part, Represents a term of degree 1 The real part; Calculating the fluorescence lifetime from the above formula, we get:

[0036] fluorescence lifetime The average time for a fluorescent material to return from the excited state to the ground state is significantly affected by temperature. Increased temperature alters the nonradiative transition rate of the material, leading to a decrease in lifetime; the total luminescence intensity of the fluorescent material... As temperature changes, fluorescence typically quenches (increases in intensity) with increasing temperature. By utilizing the sensitivity of fluorescence lifetime and fluorescence intensity to temperature, the fluorescence lifetime can be fitted. With temperature The linear relationship and fluorescence peak intensity With temperature The linear relationship was determined, and the sensitivity of the two curves was obtained respectively.

[0037] like Figure 3 The figure shows a schematic diagram of the fluorescence lifetime fitting curve of the present invention with temperature. It can be seen that when the sound pressure is kept relatively constant, as the temperature increases from 30.6℃ to 80℃, the fluorescence lifetime decreases from 176.3us to 156.6us. The linear goodness of the fluorescence lifetime-temperature fitting curve is 0.9958, and the sensitivity is -0.40296us / ℃.

[0038] like Figure 4 The figure shown is a schematic diagram of the fitting curve of the fluorescence peak intensity of the present invention as a function of temperature. It can be seen that when the sound pressure is kept relatively constant, as the temperature increases from 30.6℃ to 80℃... oDuring the C process, the fluorescence peak intensity decreased from 123.9 mV to 105.3 mV. The linear goodness of the fluorescence peak intensity versus temperature fitting curve was 0.9954, and the sensitivity was -0.38205 mV / ℃.

[0039] Example 2: This embodiment provides a dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing.

[0040] A signal generator and a voltage-to-current converter integrated module together form the excitation light driving module. A pulsed square wave signal with a duty cycle of 50% and a frequency of 500Hz is applied to the signal generator. After passing through the voltage-to-current converter integrated module, it drives the laser diode to generate pulsed excitation light with a center wavelength of 980nm and an output power of approximately 10mW. The excitation light is transmitted to a fiber optic fluorescence sensing probe via a multimode fiber, exciting the fluorescent material on the sensing probe to emit a fluorescence signal with a peak wavelength of 665nm.

[0041] The fiber optic fluorescence sensor probe was placed on a digitally displayed constant-temperature heating platform. With the indoor temperature at approximately 25°C, and by controlling the frequency of the audio transmitter to a constant value, this experiment detected fluorescence signals at different sound pressure levels by varying the sound pressure level of the transmitter under a 1000Hz acoustic signal. The generated fluorescence signal was transmitted via multimode fiber to a filter. After the filter removed the 980nm excitation light and stray light from the system's optical path, the fluorescence signal was received by a photodetector and converted into an electrical signal. The corresponding fluorescence lifetime was obtained through data processing. The output sound pressure level can be calibrated using a sound pressure meter, and the corresponding sound pressure can also be calculated using the sound pressure level formula.

[0042] Sound pressure induces mechanical deformation in hollow optical fibers (such as fiber bending and compression), leading to changes in the lattice stress of the fluorescent material. This alters the nonradiative transition rate through the Stark effect or energy level splitting, thereby affecting... The fiber deformation caused by sound pressure alters the coupling efficiency between the excitation light and the fluorescent material, resulting in periodic fluctuations in fluorescence intensity. By utilizing fluorescence lifetime and the sensitivity of fluorescence intensity to sound pressure, the fluorescence lifetime can be fitted. With sound pressure The linear relationship and fluorescence peak intensity With sound pressure The linear relationship was determined, and the sensitivity of the two curves was obtained respectively.

[0043] like Figure 5The figure shows a schematic diagram of the fluorescence lifetime fitting curve of the present invention with the change of sound pressure. It can be seen that when the temperature is kept relatively constant, as the sound pressure level increases from 70.2 dB to 91.6 dB, that is, as the sound pressure increases from 0.0647 Pa to 0.7604 Pa, the fluorescence lifetime increases from 179.8 μs to 182.4 μs. The linear goodness of the fluorescence lifetime and sound pressure fitting curve is 0.9859, and the sensitivity is 3.77779 μs / Pa.

[0044] like Figure 6 The figure shows a schematic diagram of the fluorescence peak intensity fitting curve as a function of sound pressure. It can be seen that when the temperature is kept relatively constant, as the sound pressure level increases from 70.2 dB to 91.6 dB, that is, from 0.0647 Pa to 0.7604 Pa, the fluorescence peak intensity increases from 124.6 mV to 126.7 mV. The linear goodness of the fluorescence lifetime fitting curve with sound pressure is 0.9838, and the sensitivity is 2.91608 mV / Pa.

[0045] Fiber optic fluorescence sensing devices based on dual-parameter measurements of temperature and sound pressure (SBP) exhibit cross-sensitivity because both fluorescence lifetime and fluorescence intensity are sensitive to both temperature and SBP. Therefore, a sensitivity matrix is ​​needed to eliminate cross-sensitivity. When both temperature and SBP change simultaneously, the changes in fluorescence lifetime and fluorescence intensity are a superposition of the effects of temperature and SBP. This superposition can be approximated by a polynomial:

[0046] In the formula, , These represent the changes in fluorescence lifetime and peak intensity as a function of temperature and sound pressure, respectively. , These are the changes in temperature and the changes in sound pressure, respectively. , These are the temperature sensitivity of fluorescence lifetime and fluorescence peak intensity, respectively. , The acoustic pressure sensitivity is denoted by fluorescence lifetime and fluorescence peak intensity, respectively. Converting the polynomials to matrices, the relationship between changes in fluorescence lifetime and peak fluorescence intensity and temperature-sound pressure is expressed as follows:

[0047] In the formula, by , , , The resulting matrix is ​​the sensitivity matrix. , Manifestation , The vector form after the effect of the sensitivity matrix; Multiplying both sides by the inverse of the sensitivity matrix on the left, we get:

[0048] when When the temperature and sound pressure change are measured, the above equations can be used to calculate the changes. Combined with the initial temperature and sound pressure values, the temperature and sound pressure experienced by the sensor during the detection can be determined.

[0049] Temperature and sound pressure sensitivity =-0.40296、 =-0.38205、 =3.77779、 Substituting 2.91608 into the above formula, we get:

[0050] When using a sensor to simultaneously measure temperature and sound pressure, the changes in fluorescence lifetime and peak fluorescence intensity can be obtained. Substituting these values ​​into the above formula yields the changes in temperature and sound pressure. and By combining the initial temperature and sound pressure level, the temperature and sound pressure experienced by the sensor during detection can be calculated.

[0051] It should be noted that the above are only preferred embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention using this concept also fall within the protection scope of the present invention.

Claims

1. A dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing, characterized in that, include: The excitation light output module is used to output the excitation light signal that excites the fluorescent material to generate a fluorescence signal; The fiber optic fluorescence sensing probe generates a fluorescence signal under the excitation of the excitation light signal output by the optical pulse output module. A sound pressure measuring device is used to measure the fluorescence signal generated by the fiber optic fluorescence sensing probe under different sound pressures at a constant temperature. A temperature measuring device is used to measure the fluorescence signal generated by the fiber optic fluorescence sensing probe at different temperatures when the sound pressure level is constant. A filter is used to filter out the excitation light signal mixed in with the fluorescence signal and stray light in the system's optical path; The signal detection module receives the fluorescence signal transmitted through the filter and converts the fluorescence signal into an electrical signal; The signal processing module obtains the fluorescence lifetime at different temperatures and sound pressures based on the electrical signal converted by the signal detection module; and obtains the temperature and sound pressure to be monitored based on the fluorescence lifetime at different temperatures and sound pressures.

2. The temperature and sound pressure dual-parameter measurement device based on fluorescence sensing according to claim 1, characterized in that, The method by which the signal processing module obtains the fluorescence lifetime at different temperatures and sound pressures is as follows: Perform a discrete Fourier transform on the acquired fluorescence signal to obtain the first-order term. : in, Initial fluorescence intensity; The data sampling time interval; Fluorescence lifetime; j The imaginary unit; N This represents the total number of sampling points; According to the first term The tangent of the phase angle is obtained. : in, Represents a term of degree 1 The imaginary part, Represents a term of degree 1 The real part; Based on the tangent of the phase angle Calculate fluorescence lifetime: Based on the fluorescence signals generated by the fiber optic fluorescence sensor probe at different temperatures measured by the temperature measuring device, and combined with the calculated fluorescence lifetime, a fluorescence lifetime is fitted. With temperature The linear relationship and fluorescence peak intensity With temperature Linear relationship; based on fluorescence lifetime With temperature The linear relationship between fluorescence lifetime and temperature sensitivity is obtained based on fluorescence peak intensity. With temperature The linear relationship between the fluorescence peak intensity and the temperature sensitivity is obtained. Based on the fluorescence signals generated by the fiber optic fluorescence sensor probe under different sound pressures measured by the sound pressure measuring device, and combined with the calculated fluorescence lifetime, a fluorescence lifetime is fitted. With sound pressure The linear relationship and fluorescence peak intensity With sound pressure Linear relationship; based on fluorescence lifetime With sound pressure The linear relationship between fluorescence lifetime and acoustic pressure sensitivity is obtained, based on the fluorescence peak intensity. With sound pressure The linear relationship between the fluorescence peak intensity and the acoustic pressure sensitivity is obtained.

3. The dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing according to claim 2, characterized in that, The signal processing module obtains the temperature and sound pressure to be measured based on the fluorescence lifetime at different temperatures and sound pressures using the following method: Calculate the changes in temperature and sound pressure: In the formula, The change in temperature This represents the change in sound pressure. This represents the change in fluorescence lifetime as a function of temperature and sound pressure. The fluorescence peak intensity varies with temperature and sound pressure. Temperature sensitivity of fluorescence lifetime Temperature sensitivity of fluorescence peak intensity; The acoustic pressure sensitivity is the fluorescence lifetime. The acoustic pressure sensitivity is the peak fluorescence intensity. Based on the calculated temperature and sound pressure changes, and combined with the initial temperature and initial sound pressure values, the temperature and sound pressure experienced by the sensor during detection can be determined.

4. The temperature and sound pressure dual-parameter measurement device based on fluorescence sensing according to claim 1, characterized in that, The excitation light output module includes a signal generator, a voltage-to-current integrated module, and a laser diode. The signal generator generates an electrical pulse signal with a predetermined frequency and pulse width. The voltage-to-current integrated module converts the voltage signal generated by the signal generator into a current signal. The laser diode outputs an excitation light signal under the excitation of the current signal.

5. The temperature and sound pressure dual-parameter measurement device based on fluorescence sensing according to claim 1, characterized in that, The sound pressure measuring device consists of an audio transmitter and a sound pressure meter; the temperature measuring device is heated by a digital display constant temperature heating table.

6. The dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing according to claim 1, characterized in that, The signal detection module consists of a photodetector and an oscilloscope. After receiving the fluorescence signal transmitted through the filter, the photodetector converts the fluorescence signal into an electrical signal through a photoelectric conversion circuit to obtain a fluorescence digital signal and outputs it. The complete waveform of the fluorescence signal can be observed by receiving it with the oscilloscope.

7. The temperature and sound pressure dual-parameter measurement device based on fluorescence sensing according to claim 1, characterized in that, The fiber optic fluorescence sensing probe includes: Fluorescent materials; UV optically curable adhesive; Hollow-core photonic crystal fiber; as well as Multimode optical fiber; the multimode optical fiber is fused to both ends of the hollow-core photonic crystal fiber.

8. The dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing according to claim 7, characterized in that, The fiber optic fluorescence sensing probe uses the MMF-MMF cladding alignment mode of a conventional fusion splicer to fusion multimode fiber at both ends of a hollow photonic crystal fiber. Then, the fluorescent material is mixed with optical adhesive and uniformly applied to the cladding of the hollow photonic crystal fiber after the coating layer has been removed, and then cured with a UV lamp.

9. The dual-parameter measurement device for temperature and sound pressure based on fluorescence sensing according to claim 8, characterized in that, The multimode fiber has a core diameter of 62.5 μm and a cladding diameter of 125 μm. The fluorescent material is a rare earth fluoride powder, ZnOF:Yb. 3+ Er 3+ ZnOF, as the matrix material, provides a stable lattice environment for rare earth ions; Yb 3+ As a sensitizer, it absorbs the energy of 980nm excitation light and transfers it to Er. 3+ Er 3+ As an activator, it emits photons to achieve light emission; The hollow-core photonic crystal fiber is a photonic bandgap type photonic crystal fiber with a core of 16 μm diameter air holes and a cladding diameter of 125 μm, consisting of 6 layers of air holes with a diameter of 6.35 μm. The UV optical curing adhesive is a transparent and colorless NOA61 optical adhesive that can be cured by irradiation with 365nm ultraviolet light. It has good light transmittance and elasticity and can withstand temperatures from -150℃ to 125℃.

10. A method for measuring temperature and sound pressure dual parameters based on the temperature and sound pressure dual-parameter measurement device based on fluorescence sensing according to any one of claims 1-9, comprising: When performing temperature measurements, the fiber optic fluorescence sensing probe is placed on a digital display constant temperature heating stage. Under the premise of maintaining a relatively stable sound pressure, the fluorescence signal at different temperatures is detected by controlling the temperature reading of the digital display constant temperature heating stage. The corresponding fluorescence lifetime is obtained through data processing. By utilizing the sensitivity of fluorescence lifetime and fluorescence intensity to temperature, the linear relationship between fluorescence lifetime and temperature and the linear relationship between fluorescence intensity and temperature are fitted, and the sensitivity of the two curves is obtained respectively. During sound pressure measurement, the fiber optic fluorescence sensing probe is placed on a digital display constant temperature heating platform. While maintaining a relatively stable temperature, the sound pressure level of the audio transmitter is changed by controlling its frequency to a constant value. Fluorescence signals at different sound pressure levels are detected. The output sound pressure level can be calibrated using a sound pressure meter. The corresponding sound pressure is calculated according to the sound pressure level formula, and then the corresponding fluorescence lifetime is obtained through data processing. Using the sensitivity of fluorescence lifetime and fluorescence intensity to sound pressure, linear relationships between fluorescence lifetime and sound pressure, as well as between fluorescence intensity and sound pressure, are fitted, and the sensitivity of the two curves is obtained respectively. By using a sensitivity matrix to eliminate the cross-sensitivity caused by temperature and sound pressure, the temperature and sound pressure can be obtained.

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