Sensing measurement method, device and equipment based on Fabry-Perot cavity and medium

Abstract

The invention relates to the technical field of optical sensing, and discloses a sensing measurement method, device and equipment based on a Fabry-Perot cavity and a medium, and the method comprises the steps: calculating the reflection positions of incident light with different wavelengths on a pre-constructed chirp fiber Bragg grating; calculating a wavelength range and a cavity length range according to the reflection position; calculating a wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and the cavity length range; and performing physical quantity demodulation on the wavelength interference spectrum to obtain a physical quantity measurement result. Through the implementation of the invention, the chirp Fabry-Perot interferometer of which the cavity length gradually changes along with the wavelength can be obtained, large-dynamic-range and high-resolution sensing measurement can be respectively realized in a short-wavelength region and a long-wavelength region, and the problem that the measurement resolution and the dynamic range are mutually restricted can be effectively solved; and the measurement precision of sensing measurement is improved.

Description

Technical Field

[0001] The present invention relates to the field of optical sensing technology, and in particular to a sensing measurement method, device, equipment and medium based on a Fabry-Perot cavity. Background Art

[0002] Fiber Optic Fabry-Perot Interferometer (FPI) is an instrument that creates a FP (Fabry-Pérot cavity) in the sensing area of ​​the optical fiber and uses the principle of multi-beam interference to monitor the changes in the measured value. It overcomes the polarization fading phenomenon of MZ interferometer (Mach-Zehnder interferometer) and Sagnac interferometer (Sagnac effect interferometer) structure optical fiber sensors. Due to its high sensitivity and corrosion resistance, it has been widely studied and applied to the measurement of strain, temperature, pressure, refractive index, vibration and acoustic signals. However, since the measurement resolution and dynamic range of FPI are determined by the quality factor (FOM) of the resonance peak and the free spectral range (FSR) of the interference spectrum, and for the interference spectrum with a smaller FSR, the quality factor (FOM) of the resonance peak is larger, that is, the FPI sensor has a higher measurement accuracy but a smaller dynamic measurement range. Therefore, the measurement resolution and dynamic range of FPI are often mutually constrained, which limits its use and development in the field of industrial sensing and measurement.

[0003] The existing sensing measurement methods mainly include the method of using ultra-low loss hollow core optical fiber to extend the cavity length of the external cavity FPI, which can obtain a higher FOM and improve the measurement resolution of FPI. However, the FSR reduction in the interference spectrum limits the dynamic measurement range accordingly; it also includes the method of sensing measurement of FPI based on fiber Bragg grating (FBG, Fiber Bragg Grating) pairs and chirped fiber Bragg grating (CFBG, Chirped Fiber Bragg Grating) pairs, which can significantly improve the quality factor (FOM) of the resonance peak and achieve high-resolution sensing measurement, but because their PF cavity lengths are uniform, their measurement resolution and dynamic range are also mutually restricted. Therefore, how to simultaneously ensure high-precision measurement resolution and a larger dynamic range and improve the measurement accuracy of sensing measurement has become a problem that needs to be solved urgently. Summary of the invention

[0004] The present invention provides a sensing measurement method, device, equipment and medium based on a Fabry-Perot cavity, the main purpose of which is to solve the problem of poor measurement accuracy of sensing measurement of physical quantities provided in the related art.

[0005] To achieve the above-mentioned purpose, the present invention provides a sensing measurement method based on a Fabry-Perot cavity, which is applied to a chirped Fabry-Perot interferometer. The chirped Fabry-Perot interferometer is composed of a chirped fiber Bragg grating with a flat end face. The method comprises: calculating the reflection position of incident light of different wavelengths on a pre-constructed chirped fiber Bragg grating; calculating the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position; calculating the wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and the cavity length range; and performing physical quantity demodulation on the wavelength interference spectrum to obtain a physical quantity measurement result corresponding to the incident light.

[0006] The present invention also provides a sensing and measuring device based on a Fabry-Perot cavity, comprising: a reflection position calculation module, used to calculate the reflection position of incident light of different wavelengths on a pre-constructed chirped fiber Bragg grating; a wavelength range and cavity length range calculation module, used to calculate the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position; a wavelength interference spectrum calculation module, used to calculate the wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and cavity length range; and a physical quantity demodulation module, used to perform physical quantity demodulation on the wavelength interference spectrum to obtain a physical quantity measurement result corresponding to the incident light.

[0007] The present invention also provides an electronic device, comprising: a memory communicatively connected to at least one processor; wherein the processor is used to execute a computer program stored in the memory; the memory stores a computer program executable by at least one processor, and the computer program is executed by at least one processor so that the at least one processor can execute the above-mentioned sensing measurement method based on the Fabry-Perot cavity.

[0008] The present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements any one of the above-mentioned sensing measurement methods based on the Fabry-Perot cavity.

[0009] The embodiment of the present invention calculates the wavelength range and cavity length range by calculating the reflection position of incident light of different wavelengths on the chirped fiber Bragg grating, and can obtain a chirped Fabry-Perot interferometer whose cavity length gradually changes with the wavelength; the physical quantity demodulation of the wavelength interference spectrum can realize sensing measurement with large dynamic range and high resolution in the short wavelength region and the long wavelength region respectively, which can effectively solve the problem of mutual restriction between measurement resolution and dynamic range, and improve the measurement accuracy of sensing measurement. Therefore, the sensing measurement method, device, equipment and medium based on the Fabry-Perot cavity proposed by the present invention can solve the problem of poor accuracy of sensing measurement based on the Fabry-Perot cavity. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A schematic diagram of a flow chart of a sensing measurement method based on a Fabry-Perot cavity provided in one embodiment of the present invention;

[0011] Figure 2 A schematic structural diagram of a chirped Fabry-Perot interferometer provided in one embodiment of the present invention;

[0012] Figure 3 A schematic diagram of the relationship between the cavity length and wavelength of a chirped fiber Bragg grating provided in one embodiment of the present invention;

[0013] Figure 4 An interference spectrum diagram corresponding to the interference spectrum of two chirped fiber Bragg gratings with adjacent distances but opposite directions and the interference spectrum of the chirped fiber Bragg grating with an overlapping distance of L′1 provided in one embodiment of the present invention;

[0014] Figure 5 A schematic structural diagram of the change of the central wavelength of the resonance peak of the wavelength interference spectrum with temperature provided by an embodiment of the present invention;

[0015] Figure 6 A schematic structural diagram of a sensing and measuring device based on a Fabry-Perot cavity provided in one embodiment of the present invention;

[0016] Figure 7 A schematic diagram of the structure of an electronic device for implementing a sensing measurement method based on a Fabry-Perot cavity provided by an embodiment of the present invention.

[0017] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0018] It should be understood that the specific embodiments described herein are only used to explain the present invention, and are not used to limit the present invention.

[0019] The embodiment of the present application provides a sensing measurement method based on a Fabry-Perot cavity. The execution subject of a sensing measurement method based on a Fabry-Perot cavity includes but is not limited to at least one of the electronic devices such as a server, a terminal, etc. that can be configured to execute the method provided in the embodiment of the present application. In other words, a sensing measurement method based on a Fabry-Perot cavity can be executed by software or hardware installed on a terminal device or a server device. The server includes but is not limited to: a single server, a server cluster, a cloud server or a cloud server cluster, etc. The server can be an independent server, or it can be a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communications, middleware services, domain name services, security services, content delivery networks (Content Delivery Network, CDN), and big data and artificial intelligence platforms.

[0020] Reference Figure 1 FIG. 1 is a flow chart of a sensing measurement method based on a Fabry-Perot cavity provided by an embodiment of the present invention, which specifically includes the following process:

[0021] S1. Calculate the reflection position of incident light of different wavelengths on the pre-constructed chirped fiber Bragg grating.

[0022] In one embodiment, the existing interferometer uses an ultra-low loss hollow core optical fiber to extend the cavity length of the external cavity FPI (Fiber Optic Fabry-Perot Interferometer), which can obtain a higher FOM (Figure of Merit) and improve the measurement resolution of the FPI. However, the accompanying FSR (Free Spectral Range) reduction in the interference spectrum also limits the dynamic measurement range accordingly; or the FPI based on the fiber Bragg grating (FBG) pair and the chirped fiber Bragg grating (CFBG) pair can significantly improve the quality factor (FOM) of the resonance peak and realize high-resolution sensing measurement, but because the PF cavity length is a uniform cavity, its measurement resolution and dynamic range are also restricted by each other.

[0023] Furthermore, chirped fiber Bragg gratings form chirped Fabry-Pérot Interferometers (CFPIs), which can realize interferometers in which the cavity length gradually changes with the wavelength of the incident light, showing unique spectral characteristics. They have been widely studied and applied to the measurement of strain, temperature, pressure, refractive index, vibration and acoustic signals. However, since the measurement resolution and dynamic range of FPI are determined by the quality factor (FOM) of the resonance peak and the free spectral width (FSR) of the interference spectrum, respectively, and for interference spectra with smaller FSR, the quality factor (FOM) of the resonance peak is larger, that is, the FPI sensor has higher measurement accuracy, but smaller dynamic measurement range. Therefore, the measurement resolution and dynamic range of FPI are often mutually restricted, which limits its use and development in the field of industrial sensing and measurement.

[0024] For example, the existing method of using ultra-low loss hollow core fiber to extend the cavity length of the external cavity FPI can obtain a higher FOM and improve the measurement resolution of the FPI. However, the accompanying FSR reduction in the interference spectrum also limits the dynamic measurement range accordingly. As well as FPI based on FBG pairs and CFBG pairs, both can significantly improve the quality factor (FOM) of the resonance peak and achieve high-resolution sensing measurement, but because their PF cavity lengths are uniform, the cavity length of the chirped Fabry-Perot interferometer cannot change gradually with the wavelength, resulting in the measurement resolution and dynamic range being mutually restricted.

[0025] Among them, the FOM and FSR of FPI can be expressed as:

[0026] FOM=S / △λ,FSR≈λ 2 / 2n eff L

[0027] Where S and △λ represent the sensitivity and resonance peak of the FPI sensor, respectively. eff and L represent the effective refractive index of the mode and the cavity length of the FP cavity, respectively. According to the above formula, by increasing the cavity length L of the FP cavity, a smaller FSR can be obtained, thereby obtaining a higher FOM and improving the measurement resolution of FPI; however, a smaller FSR limits the improvement of the dynamic measurement range.

[0028] In one embodiment, see Figure 2As shown, the fiber Fabry-Perot interferometer is composed of a chirped fiber Bragg grating (CFBG) and a coated end face, wherein the coated end face can be cut flat from the middle or edge of the chirped fiber Bragg grating and coated with a gold film on the cut end face, or the fiber is cut flat at the unwritten fiber at one end of the CFBG, and then a metal film is coated on the cut end face to increase the reflection of the fiber Fabry-Perot interferometer, thereby forming a similar chirped Fabry-Perot interferometer (CFPI).

[0029] In one embodiment, the reflection position of incident light of different wavelengths on a pre-constructed chirped fiber Bragg grating is calculated, including: obtaining a chirp parameter of the chirped fiber Bragg grating; constructing a reflection position formula of the incident light according to the chirp parameter; and calculating the reflection position of the incident light on the chirped fiber Bragg grating using the reflection position formula.

[0030] The chirp parameters include the mode effective refractive index, grating period, starting period and chirp rate of the chirped fiber Bragg grating. The mode effective refractive index refers to the refractive index of the phase change of the mode of the light wave propagating in the fiber Bragg grating per unit length, which directly affects the Bragg wavelength (Bragg wavelength) of the grating and the propagation characteristics of the light signal in the grating; the grating period refers to the distance between two adjacent identical structural points in the grating structure, for example, the distance between the transmission holes, reflection strips or any other periodically arranged optical structures; the starting period refers to the starting point of the first grating period of the chirped fiber Bragg grating; the chirp rate is the rate at which the grating period changes along the grating axis, which is defined as the change in the grating period per unit length. Figure 2 As shown, the starting point of the first grating period on the uncut side can be used as the starting period, and the uncut side can be used as the starting point of the reflection position, thereby determining the reflection position of each incident light.

[0031] Therefore, the reflection position formula is expressed as:

[0032]

[0033] in, Indicates wavelength as λ in The reflection position of the incident light on the chirped fiber Bragg grating, n eff represents the mode effective refractive index in the chirp parameter, Λ0 represents the starting period of the chirped fiber Bragg grating in the chirp parameter, and β represents the chirp rate in the chirp parameter.

[0034] In one embodiment, by calculating the reflection position of incident light of different wavelengths on the chirped fiber Bragg grating, the change of the cavity length of the chirped Fabry-Perot interferometer constructed by the chirped fiber Bragg grating with the wavelength of the incident light can be determined, and then the physical quantities at different wavelengths can be calculated.

[0035] S2. Calculate the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position.

[0036] In one embodiment, a Fabry-Pérot cavity, also known as an FP (Fabry–Pérot cavity), is an optical resonant cavity composed of two parallel reflective surfaces, and the cavity length refers to the distance between the two reflective surfaces.

[0037] In the embodiment of the present invention, the cavity length range is the distance between the reflection positions of the same incident light at the chirped fiber Bragg grating and the flattened end surface, and the wavelength range is the wavelength range of the incident light reflected by the chirped fiber Bragg grating.

[0038] Furthermore, the Fabry-Perot cavity can form an interferometer that can realize the gradual change of cavity length with wavelength through a chirped fiber Bragg grating and a coated end face, showing unique spectral characteristics, where the distance between CFBG and the coated end face is L1, the length of CFBG and the grating period are l and Λ respectively. z Incident light of different wavelengths will be reflected at different positions (z) of the CFBG and the coated end face, and the cavity length of the Fabry-Perot cavity will gradually change with the wavelength.

[0039] In one embodiment, the wavelength range and cavity length range of the chirped fiber Bragg grating are calculated according to the reflection position, including: identifying the wavelength range of the chirped fiber Bragg grating according to the reflection position; calculating the cavity length of each wavelength in the wavelength range; and determining the cavity length range of the chirped fiber Bragg grating according to the wavelength.

[0040] In one embodiment, since the other end of the chirped fiber Bragg grating reflects the flat end face coated with a metal film to increase reflection, the position distance is the distance between the reflection position of the incident light on the chirped fiber Bragg grating and the end face.

[0041] In one embodiment, by calculating the cavity length corresponding to each wavelength within the wavelength range, the cavity length corresponding to each wavelength can be obtained, and then the specific range of the cavity length can be determined. The wavelength range can be calculated according to the grating equation of the chirped fiber Bragg grating, for example, see Figure 2 (a) and Figure 2As shown in (b), if it is assumed that the reflection wavelength range of CFBG is λ1~λ2, and the distance between CFBG and the coated end face is L1, then the shortest cavity length corresponding to the shortest wavelength is L1, and the longest cavity length corresponding to the longest wavelength λ2 is L2=L1+l, where l represents the grating length of the chirped fiber Bragg grating.

[0042] Furthermore, for a chirped fiber Bragg grating, the grating equation can be expressed as:

[0043] λ z =2n eff Λ z ,Λ z =Λ0+β·z

[0044] Among them, λ z represents the wavelength of the reflected light at position z on the chirped fiber Bragg grating, n eff represents the preset mode effective refractive index, Λ z represents the grating period of the chirped fiber Bragg grating at position z, Λ0 represents the starting period of the chirped fiber Bragg grating, and β represents the preset chirp rate.

[0045] When the wavelength range of the chirped fiber Bragg grating is λ1 to λ2, according to the linear chirp condition, the cavity length of each wavelength in the wavelength range is calculated using the following wavelength calculation formula:

[0046]

[0047] Wherein, L(λ) represents the cavity length at wavelength λ, l represents the grating length of the chirped fiber Bragg grating, (λ1,λ2) represents the wavelength range, and L1 represents the distance from the chirped fiber Bragg grating to the flattened end face.

[0048] See also Figure 2 As shown in (c), in an embodiment of the present invention, the end face of the chirped fiber Bragg grating is cut flat from the middle or edge, and a gold film is plated on the cut end face to obtain a chirped Fabry-Perot interferometer. The gold film can increase the reflectivity of the chirped Fabry-Perot interferometer. If the length of the end face cut flat at the middle or edge of the chirped fiber Bragg grating is L′1, the shortest cavity length corresponding to the shortest wavelength λ1 is L′1, and the longest cavity length corresponding to the longest wavelength λ2 is lL′1, wherein l represents the grating length of the chirped fiber Bragg grating.

[0049] Among them, when the wavelength range of the chirped fiber Bragg grating with end face cut flat in the middle or at the edge is λ1-λ2, according to the linear chirp condition, the cavity length of each wavelength in the wavelength range is calculated using the following wavelength calculation formula:

[0050]

[0051] Wherein, L(λ) represents the cavity length at a wavelength of λ, l represents the grating length of the chirped fiber Bragg grating, (λ1,λ2) represents the wavelength range, and L′1 is the cut length of the chirped fiber Bragg grating for end face truncating.

[0052] Specifically, see Figure 3 As shown, it represents the relationship between the cavity length L and the wavelength λ of the chirped fiber Bragg grating in the chirped Fabry-Perot interferometer.

[0053] In one embodiment, an interferometer in which the cavity length gradually changes with the wavelength can be realized through different wavelength ranges and cavity length ranges, showing unique spectral characteristics, namely, a large FSR in the short wavelength region and a high FOM in the long wavelength region, which can respectively realize direct measurement of a large dynamic range and high resolution, solve the problem of mutual constraints between FPI measurement resolution and dynamic range, and improve the accuracy of physical quantity measurement.

[0054] S3. Calculate the wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and the cavity length range.

[0055] In one embodiment, the wavelength interference spectrum refers to a detailed description of the transmission or reflection response of the chirped Fabry-Perot interferometer to light of different wavelengths at different wavelengths. The reflection response usually appears as a series of sharp peaks, which specifically characterizes how the chirped Fabry-Perot interferometer changes its optical properties, such as transmittance and reflectivity, according to changes in the wavelength of light, and can link the reflection response to changes in physical quantities (such as temperature, pressure, stress, refractive index, etc.), and then the measurement of physical quantities can be calculated through the wavelength interference spectrum.

[0056] In one embodiment, see Figure 4 As shown in the figure, it is the interference spectrum of the chirped Fabry-Perot interferometer composed of a chirped fiber Bragg grating with end face cut flat in the middle or at the edge. At the short-wavelength edge of the chirped fiber Bragg grating, a larger FSR can be obtained, and the corresponding cavity length is close to zero. Therefore, CFPI has a larger dynamic measurement range and a high FOM in the long-wavelength region, which can improve the resolution of physical quantity measurement.

[0057] Specifically, after the cavity length is obtained, the wavelength interference spectrum of the chirped Fabry-Perot interferometer is expressed as:

[0058]

[0059] Where I(λ) represents the interference spectrum at wavelength λ, I1(λ) represents the intensity of incident light with wavelength λ when reflected by the chirped fiber Bragg grating, I1(λ) represents the intensity of incident light with wavelength λ when reflected by the cut flat end face, n effrepresents the mode effective refractive index, and L(λ) represents the cavity length when the wavelength is λ.

[0060] Among them, light intensity refers to the intensity of light, also called luminous flux or radiant flux. It is a physical quantity that describes the amount of light energy emitted by a light source or radiator. It is related to the brightness of the light source. Therefore, the change in wavelength can be reflected by the change in light intensity to obtain a wavelength interference spectrum.

[0061] In one embodiment, the wavelength interference spectrum can be used to calculate the interference spectrum with the maximum FSR and the highest FOM based on the shortest cavity length and the longest cavity length, thereby obtaining a larger dynamic measurement range and higher resolution sensing measurement, avoiding the constraints of the uniform cavity on the measurement resolution and dynamic range, and improving the measurement accuracy of the sensing measurement.

[0062] S4. Demodulate the wavelength interference spectrum to obtain a physical quantity measurement result corresponding to the incident light.

[0063] In one embodiment, physical quantity demodulation of the wavelength interference spectrum is to associate the interference spectrum corresponding to the interference spectrum with changes in physical quantities (such as temperature, pressure, stress, refractive index, etc.), for example, identifying the wavelength or wavelength range that is most sensitive to a specific physical quantity, thereby obtaining a measurement result of the physical quantity.

[0064] In one embodiment, a wavelength interference spectrum is demodulated for physical quantities to obtain a measurement result of a physical quantity corresponding to the incident light, including: identifying a characteristic wavelength of the physical quantity based on the wavelength interference spectrum; calculating a wavelength change of the characteristic wavelength in the wavelength interference spectrum; and performing signal demodulation on the wavelength change to obtain a measurement result of the physical quantity corresponding to the incident light.

[0065] In one embodiment, a characteristic wavelength or wavelength range associated with a change in a specific physical quantity can be identified from the wavelength interference spectrum based on the central wavelength, peak width or other spectral characteristics of the wavelength interference spectrum. As the physical quantity changes, the related characteristic wavelength will also change. The wavelength change of the characteristic wavelength can be identified using a wavelength tuning laser, wavelength scanning technology or a real-time wavelength monitoring system.

[0066] In one embodiment, signal demodulation is to extract physical information from wavelength changes. The wavelength change information can be extracted by zero crossing method, peak detection method or frequency demodulation method, so that a corresponding relationship between wavelength change and physical quantity change can be established to obtain physical quantity measurement results. This can be achieved by changing the physical quantity under controlled conditions and measuring the corresponding wavelength change.

[0067] For example, see Figure 5 (a) shows that when the temperature increases (Heating), different wavelengths

[0068] The change of reflection spectrum (Reflection) under (Wavelength), Figure 5 (b) reflects the change of reflection spectrum (Reflection) at different wavelengths (Wavelength) when the temperature drops (Cooling). Figure 5 (c) reflects the linear fit of the interference spectrum at different temperatures (Temperrature), so, Figure 5 As shown, as the temperature changes, the central wavelength of the resonance peak of the wavelength interference spectrum will drift. The temperature sensitivity is obtained by dividing the wavelength drift by the temperature change. Therefore, the temperature physical quantity can be measured by the wavelength interference spectrum.

[0069] In one embodiment, the wavelength interference spectrum can obtain the spectral characteristics of the cavity length gradually changing with the wavelength, that is, the FSR in the short wavelength region is large and the FOM in the long wavelength region is high, thereby realizing large dynamic range and high-resolution sensing measurements respectively, which can effectively solve the problem of mutual restriction between FPI measurement resolution and dynamic range and improve the measurement accuracy of sensing measurements.

[0070] The embodiment of the present invention calculates the wavelength range and cavity length range by calculating the reflection position of incident light of different wavelengths on the chirped fiber Bragg grating, and can obtain a chirped Fabry-Perot interferometer whose cavity length gradually changes with the wavelength; the physical quantity demodulation of the wavelength interference spectrum can realize sensing measurement with large dynamic range and high resolution in the short wavelength region and the long wavelength region respectively, which can effectively solve the problem of mutual restriction between measurement resolution and dynamic range, and improve the measurement accuracy of sensing measurement. Therefore, the sensing measurement method based on the Fabry-Perot cavity proposed by the present invention can solve the problem of poor accuracy of sensing measurement based on the Fabry-Perot cavity.

[0071] like Figure 6 , which is a schematic diagram of the structure of a sensing and measuring device 600 based on a Fabry-Perot cavity provided by an embodiment of the present invention. The device includes a reflection position calculation module 601, which is used to calculate the reflection position of incident light of different wavelengths on a pre-constructed chirped fiber Bragg grating; a wavelength range and cavity length range calculation module 602, which is used to calculate the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position; a wavelength interference spectrum calculation module 603, which is used to calculate the wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and cavity length range; and a physical quantity demodulation module 604, which is used to perform physical quantity demodulation on the wavelength interference spectrum to obtain a physical quantity measurement result corresponding to the incident light.

[0072] In detail, in one embodiment, the sensing and measuring device 500 based on the Fabry-Perot cavity adopts the same technical means as the sensing and measuring method based on the Fabry-Perot cavity in the accompanying drawings when in use, and can produce the same technical effects, which will not be repeated here.

[0073] like Figure 7 , is a schematic diagram of the structure of an electronic device for implementing a sensing measurement method based on a Fabry-Perot cavity provided by an embodiment of the present invention.

[0074] The electronic device 700 may include a processor 701, a memory 702, a communication bus 703, and a communication interface 704, and may also include a computer program stored in the memory 702 and executable on the processor 701, such as a sensing measurement program based on a Fabry-Perot cavity.

[0075] Among them, the processor 701 can be composed of an integrated circuit in some embodiments, for example, it can be composed of a single packaged integrated circuit, or it can be composed of multiple integrated circuits packaged with the same function or different functions, including one or more central processing units (CPU), microprocessors, digital processing chips, graphics processors and a combination of various control chips.

[0076] The memory 702 includes at least one type of readable storage medium, and the readable storage medium includes a flash memory, a mobile hard disk, a multimedia card, a card-type memory (e.g., an SD or DX memory, etc.), a magnetic memory, a disk, an optical disk, etc. In some embodiments, the memory 702 may be an internal storage unit of an electronic device, such as a mobile hard disk of the electronic device.

[0077] The communication bus 703 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The bus is configured to realize connection and communication between the memory 702 and at least one processor 701, etc.

[0078] The communication interface 704 is used for communication between the above-mentioned electronic device and other devices, including a network interface and a user interface. Optionally, the network interface may include a wired interface and / or a wireless interface (such as a WI-FI interface, a Bluetooth interface, etc.), which is generally used to establish a communication connection between the electronic device and other electronic devices. The user interface may be a display (Display), an input unit (such as a keyboard (Keyboard)), and optionally, the user interface may also be a standard wired interface or a wireless interface.

[0079] Figure 7 Only an electronic device with components is shown, and those skilled in the art will understand that Figure 7The structure shown does not constitute a limitation on the electronic device 700 , and may include fewer or more components than shown in the figure, or combine certain components, or arrange the components differently.

[0080] It should be understood that the embodiment is for illustration only and the scope of the patent application is not limited by this structure.

[0081] The present invention also provides a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, it can implement a sensing measurement method based on a Fabry-Perot cavity in any of the above embodiments. It should be noted that the computer-readable storage medium can be volatile or non-volatile. For example, the computer-readable medium may include: any entity or device that can carry computer program code, a recording medium, a USB flash drive, a mobile hard disk, a magnetic disk, an optical disk, a computer memory, and a read-only memory (ROM). In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules is only a logical function division, and there may be other division methods in actual implementation.

[0082] In addition, each functional module in each embodiment of the present invention may be integrated into one processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of hardware plus software functional modules.

[0083] It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0084] Therefore, no matter from which point of view, the embodiments should be regarded as illustrative and non-restrictive, and the scope of the present invention is limited by the appended claims rather than the above description, so it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention. Any attached figure mark in the claims should not be regarded as limiting the claims involved.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention.

Claims

1. A sensing measurement method based on a Fabry-Perot cavity, applied to a chirped Fabry-Perot interferometer, wherein the chirped Fabry-Perot interferometer is composed of a chirped fiber Bragg grating with a flat end face, characterized in that: The method comprises: Calculate the reflection position of incident light of different wavelengths on the pre-constructed chirped fiber Bragg grating; Calculating the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position; Calculating the wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and the cavity length range; The wavelength interference spectrum is demodulated for physical quantities to obtain a physical quantity measurement result corresponding to the incident light.

2. The sensing measurement method based on the Fabry-Perot cavity according to claim 1, characterized in that: The end face of the chirped fiber Bragg grating is cut flat at the middle or edge to obtain a cut flat end face.

3. The sensing measurement method based on the Fabry-Perot cavity according to claim 2, characterized in that: A gold film is plated on the flattened end surface to increase the reflectivity of the chirped Fabry-Perot interferometer.

4. The sensing measurement method based on Fabry-Perot cavity according to claim 1, characterized in that: The calculation of the reflection position of incident light of different wavelengths on the pre-constructed chirped fiber Bragg grating comprises: Obtaining a chirp parameter of the chirped fiber Bragg grating; Constructing a reflection position formula of the incident light according to the chirp parameter; The reflection position of the incident light on the chirped fiber Bragg grating is calculated using the reflection position formula.

5. The sensing measurement method based on Fabry-Perot cavity as claimed in claim 4, characterized in that: The reflection position formula is expressed as: in, Indicates wavelength as λ in The reflection position of the incident light on the chirped fiber Bragg grating, n eff represents the mode effective refractive index in the chirp parameter, Λ0 represents the starting period of the chirped fiber Bragg grating in the chirp parameter, and β represents the chirp rate in the chirp parameter.

6. The sensing measurement method based on Fabry-Perot cavity according to claim 1, characterized in that: The step of calculating the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position comprises: Identifying the wavelength range of the chirped fiber Bragg grating according to the reflection position; calculating the cavity length for each wavelength within the wavelength range; The cavity length range of the chirped fiber Bragg grating is determined according to the position cavity length.

7. The sensing measurement method based on Fabry-Perot cavity according to claim 6, characterized in that: The calculating the cavity length of each wavelength within the wavelength range comprises: The cavity length of each wavelength within the wavelength range is calculated using a preset cavity length calculation formula, wherein the cavity length calculation formula is expressed as: Where L(λ) represents the cavity length at wavelength λ, l represents the grating length of the chirped fiber Bragg grating, (λ1,λ2) represents the wavelength range, and L ′ 1 is the cutting length of the chirped fiber Bragg grating for end face cutting.

8. The sensing measurement method based on Fabry-Perot cavity according to claim 1, characterized in that: The wavelength interference spectrum is expressed as: Where I(λ) represents the interference spectrum at wavelength λ, I1(λ) represents the intensity of incident light with wavelength λ when reflected by the chirped fiber Bragg grating, I1(λ) represents the intensity of incident light with wavelength λ when reflected by the cut flat end face, n eff represents the mode effective refractive index, and L(λ) represents the cavity length when the wavelength is λ.

9. The sensing measurement method based on Fabry-Perot cavity according to claim 1, characterized in that: The performing physical quantity demodulation on the wavelength interference spectrum to obtain a physical quantity measurement result corresponding to the incident light includes: identifying a characteristic wavelength of a physical quantity according to the wavelength interference spectrum; Calculate the wavelength change of the characteristic wavelength in the wavelength interference spectrum; The wavelength change is subjected to signal demodulation to obtain a physical quantity measurement result corresponding to the incident light.

10. A sensing measurement device based on a Fabry-Perot cavity, characterized in that: The device comprises: A reflection position calculation module, used to calculate the reflection position of incident light of different wavelengths on a pre-constructed chirped fiber Bragg grating; A wavelength range and cavity length range calculation module, used to calculate the wavelength range and cavity length range of the chirped fiber Bragg grating according to the reflection position; A wavelength interference spectrum calculation module, used to calculate the wavelength interference spectrum of the chirped fiber Bragg grating according to the wavelength range and the cavity length range; The physical quantity demodulation module is used to perform physical quantity demodulation on the wavelength interference spectrum to obtain a physical quantity measurement result corresponding to the incident light.

11. An electronic device, characterized in that: The electronic device comprises: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, The processor is used to execute the computer program stored in the memory; The memory stores a computer program executable by the at least one processor, and the computer program is executed by the at least one processor so that the at least one processor can perform the sensing measurement method based on the Fabry-Perot cavity as described in any one of claims 1 to 9.

12. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, the sensing measurement method based on the Fabry-Perot cavity described in any one of claims 1 to 9 is implemented.

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