Dual-mode fused temperature demodulation method

Abstract

The invention relates to the technical field of temperature monitoring, in particular to a dual-mode fused temperature demodulation method, which comprises the following steps of: extracting interference spectrum peak offset, and comparing and analyzing the interference spectrum peak offset with a first temperature wavelength curve to obtain a first temperature; determining an absorption edge wavelength, and comparing and analyzing the absorption edge wavelength with the second temperature wavelength curve to obtain a second temperature; and analyzing the first temperature and the second temperature to obtain an analyzed temperature. Independent temperature data are obtained through the first light path and the second light path respectively, the first temperature is based on the Fabry-Perot cavity, but wavelength shift caused by temperature change obtained based on the Fabry-Perot cavity possibly spans multiple interference periods, demodulation blur is caused, the second temperature is demodulated through the absorption edge wavelength in the second reflection spectrum, and demodulation blur is caused. The second temperature is a temperature interval, according to the temperature interval, the problem of interference spectrum overlapping in a wide temperature range is effectively solved, and high-precision temperature demodulation in the wide temperature range is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of temperature monitoring, and particularly relates to a temperature demodulation method for dual-mode fusion. Background Art

[0002] In the existing temperature monitoring technologies, the non-contact temperature measurement method based on optical reflection spectroscopy has been widely applied in industrial, medical, and scientific research fields due to its advantages such as anti-electromagnetic interference, high sensitivity, and fast response. However, the traditional optical temperature measurement method has the following problems: environmental interference affects the accuracy, and environmental factors (such as dust, vibration, or light source fluctuations) during the optical path transmission may cause the reflection spectrum signal to shift, thereby introducing temperature demodulation errors. The reliability of a single sensor is insufficient. When relying solely on a single temperature detection unit, if its material properties change due to aging or process deviation, the temperature measurement result will lose accuracy. Cross-cycle demodulation is difficult. In interferometric sensors such as Fabry-Perot (FP) cavities, the wavelength shift caused by temperature changes may span multiple interference cycles, resulting in demodulation ambiguity.

[0003] Therefore, how to achieve high-precision and anti-interference temperature analysis is a current research direction. Summary of the Invention

[0004] (I) Object of the Invention

[0005] The object of the present invention is to provide a temperature demodulation method for dual-mode fusion that can automatically analyze, determine a specific temperature range through one mode, analyze and obtain high-precision data through the other mode, and finally obtain high-precision temperature, realizing high-precision temperature measurement within a wide temperature range.

[0006] (II) Technical Solution

[0007] To solve the above problems, the present invention provides a temperature demodulation method for dual-mode fusion, including:

[0008] Extracting the interference spectrum peak shift amount in the first reflection spectrum obtained by the first optical path module based on the first direct bandgap semiconductor temperature detection unit, comparing and analyzing the interference spectrum peak shift amount with the first temperature wavelength curve to obtain the first temperature;

[0009] Determining the absorption edge wavelength in the second reflection spectrum obtained by the second optical path module based on the second direct bandgap semiconductor temperature detection unit, comparing and analyzing the absorption edge wavelength with the second temperature wavelength curve to obtain the second temperature;

[0010] Analyzing the first temperature and the second temperature to obtain the analyzed temperature.

[0011] On the other hand of the present invention, preferably, the first temperature wavelength curve is obtained through the following steps:

[0012] The first direct bandgap semiconductor temperature detection unit forms a Fabry-Perot cavity through a direct bandgap semiconductor crystal, sets a reflection medium at the reflection end of the direct bandgap semiconductor crystal, and obtains a first reflection spectrum at different experimental temperatures;

[0013] Extract the offset of the interference spectrum in the first reflection spectrum;

[0014] Use a standard thermometer to calibrate the actual temperature data to obtain calibrated temperature data;

[0015] According to the calibrated temperature data and the offset of the interference spectrum, obtain a first temperature-wavelength curve.

[0016] On the other hand, preferably, the second temperature-wavelength curve is obtained through the following steps:

[0017] The second direct bandgap semiconductor temperature detection unit reflects through a direct bandgap semiconductor crystal material to obtain a second reflection spectrum at different experimental temperatures;

[0018] Determine the absorption edge wavelength in the second reflection spectrum;

[0019] According to the functional relationship between the absorption edge wavelength and temperature, obtain a second temperature-wavelength curve;

[0020] The functional relationship between the absorption edge wavelength and temperature is obtained according to the relationship between the absorption edge wavelength and the bandgap width and the functional relationship between the bandgap width and temperature.

[0021] On the other hand, preferably, the offset of the interference spectrum in the first reflection spectrum is extracted through the following steps:

[0022] Based on the characteristic that the refractive index of the direct bandgap semiconductor crystal changes with temperature, analyze the change in the optical path traveled by light of each wavelength in the interference spectrum in the Fabry-Perot cavity;

[0023] According to the change, extract the offset of the interference spectrum in the reflection spectrum data.

[0024] On the other hand, preferably,

[0025] The first reflection spectrum is represented by the following formula (1):

[0026]

[0027] Among them, R FP represents the first reflection spectrum, R1 represents the reflectivity of the incident end of the direct bandgap semiconductor crystal, R2 represents the reflectivity of the reflection end of the direct bandgap semiconductor, and φ represents the phase difference between adjacent light beams.

[0028] On the other hand of the present invention, preferably, the phase difference between the adjacent light beams is expressed by the following formula (2):

[0029]

[0030] wherein, φ represents the phase difference between the adjacent light beams, n1 represents the refractive index of the direct bandgap semiconductor crystal, λ represents the incident light wavelength at the incident end of the direct bandgap semiconductor crystal, θ represents the incident angle, and L represents the cavity length of the Fabry-Perot cavity.

[0031] On the other hand of the present invention, preferably,

[0032] When the incident angle is 0, and when the incident light wavelength λ and the cavity length L satisfy the following formula (3), the reflected light of the light wavelength undergoes constructive interference:

[0033] 2nL = m1λ (3);

[0034] When the incident angle is 0, and when the incident light wavelength λ and the cavity length L satisfy the following formula (4), the reflected light of the light wavelength undergoes destructive interference:

[0035]

[0036] wherein, 2nL represents the optical path that the light travels in the Fabry-Perot cavity, m1 and m2 are integers, and λ represents the incident light wavelength at the incident end of the direct bandgap semiconductor crystal.

[0037] On the other hand of the present invention, preferably,

[0038] The functional relationship between the absorption edge wavelength and the temperature is expressed by the following formula (5):

[0039]

[0040] wherein, λ g represents the absorption edge wavelength of the direct bandgap semiconductor crystal, T represents the temperature, h is the Planck constant, c is the speed of light, E g (0) is the bandgap width of the direct bandgap semiconductor crystal at an ambient temperature of 0K, γ represents the bandgap temperature coefficient, and β represents the temperature fitting constant.

[0041] On the other hand of the present invention, preferably,

[0042] The relationship between the absorption edge wavelength and the bandgap width is expressed by the following formula (6):

[0043]

[0044] wherein, λ g represents the absorption edge wavelength of the direct bandgap semiconductor crystal, h is the Planck constant, c is the speed of light, Eg is the bandgap width of a direct bandgap semiconductor crystal.

[0045] On the other hand, preferably,

[0046] the function of the bandgap width and temperature is expressed by the following formula (7):

[0047]

[0048] where E g is the bandgap width of a direct bandgap semiconductor crystal, T represents temperature, and E g (0) is the bandgap width of a direct bandgap semiconductor crystal at an ambient temperature of 0K, γ represents the bandgap temperature coefficient, and β represents the temperature fitting constant.

[0049] (III) Beneficial effects

[0050] The above technical solution of the present invention has the following beneficial technical effects:

[0051] The present invention obtains independent temperature data through the first optical path and the second optical path respectively. The first temperature is based on the Fabry-Perot cavity, but the wavelength shift caused by the temperature change obtained based on the Fabry-Perot cavity may span multiple interference periods, resulting in demodulation ambiguity. The second temperature is demodulated through the absorption edge wavelength in the second reflection spectrum. The second temperature is a temperature range. According to the temperature range, the problem of interference spectrum overlap in a wide temperature range is effectively solved, and high-precision temperature demodulation in a wide temperature range is achieved. Description of the drawings

[0052] Figure 1 is a schematic diagram of the overall process of an embodiment of the present invention;

[0053] Figure 2 is a schematic diagram of the temperature sensor structure of an embodiment of the present invention;

[0054] Figure 3 is a graph of the relationship between the absorption coefficient of GaAs and the photon energy of an embodiment of the present invention;

[0055] Figure 4 is a graph of the relationship between the absorption edge wavelength and temperature of an embodiment of the present invention;

[0056] Figure 5 is a schematic diagram of the first reflection spectrum (left) and the second reflection spectrum (right) of an embodiment of the present invention;

[0057] Figure 6 is the first reflection spectrum of an embodiment of the present invention;

[0058] Figure 7 is the preprocessed first reflection spectrum diagram of an embodiment of the present invention;

[0059] Figure 8 is the Gaussian fitting curve graph of an embodiment of the present invention;

[0060] Figure 9 is the first temperature-wavelength curve graph of an embodiment of the present invention;

[0061] Figure 10 is the first reflection spectrum graphs at -20°C, 5°C and 10°C of an embodiment of the present invention;

[0062] Figure 11 is the second reflection spectrum graph of an embodiment of the present invention;

[0063] Figure 12 is the second temperature-wavelength curve graph of an embodiment of the present invention. Detailed Embodiments

[0064] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the detailed embodiments and the accompanying drawings. It should be understood that these descriptions are merely exemplary and are not intended to limit the scope of the present invention. In addition, in the following descriptions, descriptions of well-known structures and technologies are omitted to avoid unnecessarily obscuring the concepts of the present invention.

[0065] Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0066] In the description of the present invention, it should be noted that the terms "first", "second", and "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0067] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0068] The present invention will be described in more detail below with reference to the accompanying drawings. In each of the drawings, like elements are denoted by like reference numerals. For the sake of clarity, the various parts in the drawings are not drawn to scale.

[0069] Embodiment 1

[0070] A temperature demodulation method for dual-mode fusion. The temperature monitoring method in this embodiment is based on a temperature monitoring system, which includes a first optical path module, a second optical path module, a temperature sensor, and a calculation and analysis module; the temperature sensor includes a first direct-bandgap semiconductor temperature detection unit and a second direct-bandgap semiconductor temperature detection unit; the first optical path module outputs a first optical signal to the temperature sensor, and the first direct-bandgap semiconductor temperature detection unit of the temperature sensor reflects and generates a first reflection spectrum, which is transmitted to the calculation and analysis module; the second optical path module outputs a second optical signal, which is transmitted to the temperature sensor, and the second direct-bandgap semiconductor temperature detection unit of the temperature sensor reflects and generates a second reflection spectrum, which is transmitted to the calculation and analysis module; the calculation and analysis module obtains the analyzed temperature according to the first reflection spectrum and the second reflection spectrum. Among them, the optical wavelengths generated by the first optical path module and the second optical path module are different. The temperature sensor includes a direct-bandgap semiconductor crystal. The first direct-bandgap semiconductor temperature detection unit is a Fabry-Perot cavity formed based on the direct-bandgap semiconductor crystal structure, and the second direct-bandgap semiconductor temperature detection unit is the reflection of the direct-bandgap semiconductor crystal material itself.

[0071] Figure 1 The overall flowchart of an embodiment of the present invention is shown, as Figure 1 shown, including: extracting the interference spectrum peak offset in the first reflection spectrum obtained by the first optical path module based on the first direct-bandgap semiconductor temperature detection unit, comparing and analyzing the interference spectrum peak offset with the first temperature wavelength curve, and obtaining the first temperature; Figure 2 The structural schematic diagram of the temperature sensor in an embodiment of the present invention is shown, as Figure 2 shown. The temperature sensor includes an optical fiber 1, a direct-bandgap semiconductor crystal 2, and a reflection medium 3. In this embodiment, the first direct-bandgap semiconductor temperature detection unit is a Fabry-Perot cavity structure formed based on the structure of the direct-bandgap semiconductor crystal 2. The structural composition includes: the direct-bandgap semiconductor crystal 2 forms an FP cavity structure, the two ends of the direct-bandgap semiconductor crystal 2 are arranged in parallel to form an incident end and a reflection end, and the two end faces of the incident end and the reflection end serve as the parallel mirrors of the FP cavity. The reflection medium is located outside the FP cavity and is used to generate the first reflection spectrum. The working principle is that after the incident optical signal enters the direct-bandgap semiconductor crystal 2, it is reflected and transmitted multiple times by the reflection medium between the incident end and the reflection end, forming parallel light beams with decreasing amplitudes. These light beams interfere with each other to generate the first reflection spectrum. The temperature sensing mechanism is that temperature changes will cause the thermal expansion effect of the direct-bandgap semiconductor. The thermal expansion changes the optical path difference of the FP cavity, and the change in the optical path difference causes the interference spectrum to shift. High-precision temperature measurement can be achieved by detecting the offset of the interference spectrum. The direct-bandgap semiconductor crystal 2 material includes, but is not limited to: gallium arsenide (GaAs), gallium nitride (GaN), indium phosphide (InP).

[0072] In this embodiment, the first temperature-wavelength curve is obtained through the following steps:

[0073] The first direct bandgap semiconductor temperature detection unit forms a Fabry-Perot cavity through a direct bandgap semiconductor crystal, and a reflective medium is set at the reflection end of the direct bandgap semiconductor crystal to obtain the first reflection spectrum at different experimental temperatures. Equipment such as a dry well furnace and a constant temperature oil bath is used to provide a constant temperature environment for the sensor, covering a temperature range from -20°C to 150°C, with a temperature change step of 5°C. A spectral data acquisition card and a spectrometer are used to collect the reflection spectra at different temperatures in two bands. In this embodiment, the material of the direct bandgap semiconductor crystal 2 is gallium arsenide (GaAs). Figure 5 It is a schematic diagram of the first reflection spectrum (left) and the second reflection spectrum (right) of an embodiment of the present invention. As Figure 5 shown, taking the experimental data at 0°C as an example, the reflection spectrum is divided into the 880nm segment of the second reflection spectrum and the 1550nm segment of the first reflection spectrum. To ensure the integrity of the collected data and the repeatability of the experiment, 10 groups of reflection spectrum data are collected for each temperature. Figure 6 It shows the first reflection spectrum diagram of an embodiment of the present invention. As Figure 6 shown, in order to reduce errors, the intensity of 10 groups of spectral data is averaged and then participates in the demodulation calculation. The wavelength demodulation is performed on the 1550nm segment of the first reflection spectrum. Figure 7 It is the preprocessed first reflection spectrum diagram of an embodiment of the present invention. As Figure 7 shown, Gaussian filtering is performed on the original data of the first reflection spectrum to strengthen the signal and reduce noise interference; subsequently, the data is normalized to ensure the comparability of the data under different test conditions. After preprocessing, the final real first reflection spectrum data is clearer and smoother.

[0074] The offset of the interference spectrum in the first reflection spectrum is extracted using a peak-finding algorithm; the offset of the interference spectrum in the first reflection spectrum is extracted through the following steps: based on the characteristic that the refractive index of the direct bandgap semiconductor crystal changes with temperature, analyze the change in the optical path traveled by the light of each wavelength in the interference spectrum in the Fabry-Perot cavity; according to the change, extract the offset of the interference spectrum in the reflection spectrum data. The first reflection spectrum is represented by the following formula (1):

[0075]

[0076] where R FP represents the first reflection spectrum, R1 represents the reflectivity of the incident end of the direct bandgap semiconductor crystal, R2 represents the reflectivity of the reflection end of the direct bandgap semiconductor, and φ represents the phase difference between adjacent light beams.

[0077] The phase difference between adjacent light beams is represented by the following formula (2):

[0078]

[0079] Among them, φ represents the phase difference between adjacent light beams, n1 represents the refractive index of the direct bandgap semiconductor crystal, λ represents the incident light wavelength at the incident end of the direct bandgap semiconductor crystal, θ represents the incident angle, and L represents the cavity length of the Fabry-Perot cavity.

[0080] When the incident angle is 0 and the incident light wavelength λ and the cavity length L satisfy the following formula (3), the reflected light of the light wavelength undergoes constructive interference:

[0081] 2nL = m1λ (3);

[0082] When the incident angle is 0 and the incident light wavelength λ and the cavity length L satisfy the following formula (4), the reflected light of the light wavelength undergoes destructive interference:

[0083]

[0084] Among them, 2nL represents the optical path that light travels in the Fabry-Perot cavity, m1 and m2 are integers, and λ represents the incident light wavelength at the incident end of the direct bandgap semiconductor crystal.

[0085] Specifically, after performing normalization processing on the original spectral data, the second single peak of the first reflection spectrum at -20°C is selected as the offset spectrum reference, and the corresponding temperature change information is obtained by demodulating and analyzing the wavelength offset of this peak. Figure 8 The Gaussian fitting curve graph of an embodiment of the present invention is shown. As Figure 8 shown, to find a more accurate peak wavelength value, Gaussian fitting is performed on the selected single-peak spectral data. The function model after fitting is used to reconstruct the spectrum at a wavelength interval of 0.1 pm. High-precision Gaussian fitting can overcome the resolution limitation of the spectral data acquisition card. Gaussian fitting peak positioning can obtain a more accurate spectral peak than the original sampling points, further demodulate a higher-precision temperature value, use a standard thermometer to calibrate the actual temperature data, and obtain the calibrated temperature data; according to the calibrated temperature data and the offset of the interference spectrum, the first temperature-wavelength curve is obtained. Figure 9 The first temperature-wavelength curve graph of an embodiment of the present invention is shown. As Figure 9 shown, the first temperature-wavelength curve is obtained through linear fitting of the peak offset of the interference spectrum at different temperatures. As the temperature increases, the GaAs interference spectrum will undergo a red shift, with a temperature sensitivity of 0.12 nm / °C and a fitting coefficient of 0.9997. Through analysis and calculation of the calibration value and the fitting value, the temperature demodulation error is obtained as ±1.0419°C.

[0086] When the temperature measurement range of the GaAs temperature probe is too large, the offset of its interference spectrum will exceed the free spectral range. Figure 10 The first reflection spectrogram at -20°C, 5°C, and 10°C according to an embodiment of the present invention is shown. As Figure 10 shown, taking the spectrogram at -20°C as a reference, during the process of the spectrum redshift with the increase in temperature, during the process of heating from 5°C to 10°C, the spectral offset exceeds the free spectral range, and during this heating process, there must be an interference spectrum corresponding to a certain temperature value that overlaps with the spectrum at -20°C, resulting in demodulation chaos.

[0087] In this embodiment, the absorption edge wavelength in the second reflection spectrum obtained by the second optical path module based on the second direct bandgap semiconductor temperature detection unit is determined, and the absorption edge wavelength is compared and analyzed with the second temperature wavelength curve to obtain the second temperature; the second direct bandgap semiconductor temperature detection unit realizes temperature measurement based on the optical absorption characteristics of the direct bandgap semiconductor crystal material. The basic physical mechanism is as follows: the second direct bandgap semiconductor temperature detection unit uses a direct bandgap semiconductor crystal (such as GaAs, GaN, or InP) as the temperature sensing medium. When the incident photon energy exceeds the semiconductor bandgap width, valence band electrons will undergo intrinsic absorption transitions. The critical wavelength is defined as the absorption edge wavelength. When the wavelength is greater than the absorption edge wavelength, it means that the photon energy is insufficient and the light wave is reflected; when the wavelength is less than or equal to the absorption edge wavelength, strong absorption occurs and the reflectivity drops sharply; the change in temperature causes the change in the bandgap width and the shift of the absorption edge position. When the temperature rises, the absorption edge shifts to the right; when the temperature drops, the absorption edge shifts to the left.

[0088] In this embodiment, the second temperature wavelength curve is obtained through the following steps:

[0089] The second direct bandgap semiconductor temperature detection unit obtains the second reflection spectrum at different experimental temperatures through the reflection of the direct bandgap semiconductor crystal material. Figure 11 The second reflection spectrogram according to an embodiment of the present invention is shown. As Figure 11 shown, after averaging 10 groups of spectral data collected in the absorption edge offset section and then performing secondary Gaussian filtering to filter out most of the noise and improve the signal quality, normalization processing is then performed to obtain the second reflection spectrum.

[0090] Determine the absorption edge wavelength in the second reflection spectrum; according to the functional relationship between the absorption edge wavelength and temperature, obtain the second temperature wavelength curve. Figure 12 The second temperature wavelength curve diagram according to an embodiment of the present invention is shown. As Figure 12As shown, taking the normalized reflection spectrum data of the absorption edge offset section at -20°C as the reference, the offset of the spectrum at different temperatures to the reference spectrum is calculated through the cross-correlation algorithm, and the second temperature-wavelength curve is obtained through linear fitting, with a temperature sensitivity of 0.36 nm / °C and a fitting coefficient of 0.99.

[0091] The functional relationship between the absorption edge wavelength and temperature is obtained based on the relationship between the absorption edge wavelength and the bandgap width and the functional relationship between the bandgap width and temperature.

[0092] The functional relationship between the absorption edge wavelength and temperature is expressed by the following formula (5):

[0093]

[0094] where λ g represents the absorption edge wavelength of the direct bandgap semiconductor crystal, T represents temperature, h is Planck's constant, c is the speed of light, and E g (0) is the bandgap width of the direct bandgap semiconductor crystal at an ambient temperature of 0K, γ represents the bandgap temperature coefficient, and β represents the temperature fitting constant.

[0095] The relationship between the absorption edge wavelength and the bandgap width is expressed by the following formula (6):

[0096]

[0097] where λ g represents the absorption edge wavelength of the direct bandgap semiconductor crystal, h is Planck's constant, c is the speed of light, and E g is the bandgap width of the direct bandgap semiconductor crystal.

[0098] The functional relationship between the bandgap width and temperature is expressed by the following formula (7):

[0099]

[0100] where E g is the bandgap width of the direct bandgap semiconductor crystal, T represents temperature, E g (0) is the bandgap width of the direct bandgap semiconductor crystal at an ambient temperature of 0K, γ represents the bandgap temperature coefficient, and β represents the temperature fitting constant.

[0101] Figure 3 shows the relationship diagram between the absorption coefficient of GaAs and the photon energy in an embodiment of the present invention; Figure 4 shows the relationship diagram between the absorption edge wavelength and temperature in an embodiment of the present invention; as Figure 3 and Figure 4 shown, when the direct bandgap semiconductor crystal is GaAs, E g(0) = 1.522 eV, which is the bandgap width at an ambient temperature of 0 K, γ = 5.8×10 -4 eV / K and β = 300 K are the inherent properties of the GaAs material, then Equation (5) is expressed as:

[0102]

[0103] Taking the derivative of both sides of the equation with respect to T gives:

[0104]

[0105] As Figure 4 shown, the absorption edge wavelength λ of GaAs g is positively correlated with the temperature T. At an ambient temperature of 250 - 500 K, the range of λ g is between 855 - 945 nm, and there is an approximately linear relationship between the two, so the second temperature can be obtained.

[0106] Analyzing the first temperature and the second temperature to obtain an analytical temperature, including: the second temperature is used to locate the temperature range, and the first temperature is analyzed through the temperature range to obtain the analytical temperature.

[0107] In the present invention, independent temperature data are obtained through the first optical path and the second optical path respectively. The first temperature is based on the Fabry - Perot cavity, but the wavelength shift caused by the temperature change obtained based on the Fabry - Perot cavity may span multiple interference cycles, resulting in demodulation ambiguity. The second temperature is demodulated through the absorption edge wavelength in the second reflection spectrum. The second temperature is a temperature range, and according to the temperature range, the problem of interference spectrum overlap in a wide temperature range is effectively solved, realizing high - precision temperature demodulation in a wide temperature range.

[0108] It should be understood that the above - mentioned specific embodiments of the present invention are only used for exemplary illustration or explanation of the principle of the present invention, and do not constitute a limitation to the present invention. Therefore, any modifications, equivalent replacements, improvements, etc. made without departing from the spirit and scope of the present invention shall be included within the protection scope of the present invention. In addition, the appended claims of the present invention are intended to cover all changes and modification examples falling within the scope and boundaries of the appended claims, or equivalent forms of such scope and boundaries.

[0109] The present invention has been described above with reference to the embodiments of the present invention. However, these embodiments are only for the purpose of illustration and not for the purpose of limiting the scope of the present invention. The scope of the present invention is defined by the appended claims and their equivalents. Without departing from the scope of the present invention, those skilled in the art can make various substitutions and modifications, and these substitutions and modifications should all fall within the scope of the present invention.

[0110] Although the embodiments of the present invention have been described in detail, it should be understood that various changes, substitutions, and alterations can be made to the embodiments of the present invention without departing from the spirit and scope of the present invention.

[0111] Obviously, the above examples are only for illustration purposes and are not intended to limit the embodiments. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the embodiments here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A temperature demodulation method for dual-mode fusion, characterized in that Including: Extracting the peak shift of the interference spectrum in the first reflection spectrum obtained by the first optical path module based on the first direct bandgap semiconductor temperature detection unit, comparing and analyzing the peak shift of the interference spectrum with the first temperature-wavelength curve to obtain the first temperature; Determining the absorption edge wavelength in the second reflection spectrum obtained by the second optical path module based on the second direct bandgap semiconductor temperature detection unit, comparing and analyzing the absorption edge wavelength with the second temperature-wavelength curve to obtain the second temperature; Analyzing the first temperature and the second temperature to obtain the analyzed temperature.

2. The temperature demodulation method of dual-mode fusion according to claim 1, characterized in that The first temperature-wavelength curve is obtained through the following steps: The first direct bandgap semiconductor temperature detection unit forms a Fabry-Perot cavity through a direct bandgap semiconductor crystal, sets a reflection medium at the reflection end of the direct bandgap semiconductor crystal, and obtains the first reflection spectrum at different experimental temperatures; Extracting the shift of the interference spectrum in the first reflection spectrum; Calibrating the actual temperature data using a standard thermometer to obtain the calibrated temperature data; Obtaining the first temperature-wavelength curve according to the calibrated temperature data and the shift of the interference spectrum.

3. The temperature demodulation method for dual-mode fusion according to claim 1, characterized in that The second temperature-wavelength curve is obtained through the following steps: The second direct bandgap semiconductor temperature detection unit reflects through a direct bandgap semiconductor crystal material to obtain the second reflection spectrum at different experimental temperatures; Determining the absorption edge wavelength in the second reflection spectrum; Obtaining the second temperature-wavelength curve according to the functional relationship between the absorption edge wavelength and temperature; The functional relationship between the absorption edge wavelength and temperature is obtained according to the relationship between the absorption edge wavelength and the bandgap width and the functional relationship between the bandgap width and temperature.

4. The temperature demodulation method for dual-mode fusion according to claim 2, characterized in that, The shift of the interference spectrum in the first reflection spectrum is extracted through the following steps: Based on the characteristic that the refractive index of the direct bandgap semiconductor crystal changes with temperature, analyzing the change in the optical path traveled by the light of each wavelength in the interference spectrum in the Fabry-Perot cavity; Extracting the shift of the interference spectrum in the reflection spectrum data according to the change.

5. The dual-mode fusion temperature demodulation method according to claim 4, wherein The first reflection spectrum is represented by the following formula (1): wherein, R FP represents a first reflection spectrum, R1 represents the reflectivity of the incident end of the direct bandgap semiconductor crystal, R2 represents the reflectivity of the reflection end of the direct bandgap semiconductor, and φ represents the phase difference between adjacent light beams.

6. The temperature demodulation method of dual-mode fusion according to claim 5, characterized in that The phase difference between adjacent light beams is represented by the following formula (2): Wherein, φ represents the phase difference between adjacent light beams, n1 represents the refractive index of the direct bandgap semiconductor crystal, λ represents the incident light wavelength at the incident end of the direct bandgap semiconductor crystal, θ represents the incident angle, and L represents the cavity length of the Fabry-Perot cavity.

7. The dual-mode fusion temperature demodulation method according to claim 6, wherein When the incident angle is 0 and the incident light wavelength λ and the cavity length L satisfy the following formula (3), the reflected light of the light wavelength undergoes constructive interference: 2nL = m1λ (3); When the incident angle is 0 and the incident light wavelength λ and the cavity length L satisfy the following formula (4), the reflected light of the light wavelength undergoes destructive interference: Wherein, 2nL represents the optical path traveled by the light in the Fabry-Perot cavity, m1 and m2 are integers, and λ represents the incident light wavelength at the incident end of the direct bandgap semiconductor crystal.

8. The dual-mode fusion temperature demodulation method according to claim 3, wherein The functional relationship between the absorption edge wavelength and temperature is expressed by the following formula (5): Among them, λ g represents the absorption edge wavelength of the direct bandgap semiconductor crystal, T represents temperature, h is Planck's constant, c is the speed of light, and E g (0) is the bandgap width of the direct bandgap semiconductor crystal at an ambient temperature of 0K, γ represents the bandgap temperature coefficient, and β represents the temperature fitting constant.

9. The temperature demodulation method of dual-mode fusion according to claim 3, characterized in that The relationship between the absorption edge wavelength and the band gap width is expressed by the following formula (6): Among them, λ g represents the absorption edge wavelength of the direct bandgap semiconductor crystal, h is Planck's constant, c is the speed of light, and E g is the bandgap width of the direct bandgap semiconductor crystal.

10. The temperature demodulation method of dual-mode fusion according to claim 3, characterized in that The function of the band gap width and temperature is expressed by the following formula (7): Among them, E g is the bandgap width of the direct bandgap semiconductor crystal, T represents temperature, and E g (0) is the bandgap width of the direct bandgap semiconductor crystal at an ambient temperature of 0 K. γ represents the bandgap temperature coefficient, and β represents the temperature fitting constant.

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