Transformation spectrometer based on temperature change reflectivity spectrum

Abstract

The invention discloses a transformation spectrometer based on a temperature change reflectivity spectrum, and relates to the technical field of spectrometer design. According to the spectrograph, the temperature is used as an independent variable, the change of the complex refractive index of the thermally induced phase change material in the phase change temperature interval is converted into the change of the reflection spectrum of the interference film along with the temperature, the reflection light intensity signal in the phase change process is measured in real time, and the temperature change reflectivity spectrum of the interference film is combined to invert the incident spectrum, so that the temperature change reflectivity of the interference film is calculated. And the function of measuring an unknown incident spectrum by the spectrometer is realized. According to the spectrograph, the optical property of the thermally induced phase change material can be controlled through temperature in a phase change temperature region, and then the thermally induced phase change material is designed to have a regulation and control function of the spectrograph, that is, the conventional movable mirror regulation and control are replaced by thermally induced phase change regulation and control, so that the miniaturization of the spectrograph is realized. On the basis of the design idea of thermally induced phase change, by adjusting conditions such as material selection of the dielectric layer and parameter design of the film layer structure, the design of the spectrograph of any working wave band can be realized.

Description

Technical Field

[0001] The invention relates to the technical field of spectrometer design, and in particular to a transformation spectrometer based on temperature-dependent reflectivity spectrum. Background Art

[0002] Spectrometers are widely used in the field of material analysis, but traditional spectrometers are limited in practicality and scope of application in real-time spectral detection due to their large size, high price and complex operation steps. Therefore, the emergence of miniature spectrometers is particularly important. With its advantages such as small size, low cost and simple operation, this type of instrument effectively overcomes the limitations of traditional spectrometers and meets the needs of small enterprises and individual users. At the same time, it improves detection efficiency and shows broader prospects in practical applications. The development of nanophotonics manufacturing technology and the emergence of strong light-matter interactions in silicon devices have enabled the application of spectroscopy technology in chip systems. This major advancement has greatly reduced the size of the device and expanded the application range of miniaturized spectrometers.

[0003] The current research on the control mechanism of spectrometers can be roughly divided into: dispersion control spectrometers represented by gratings, Fourier transform spectrometers based on Michelson interference, etc. Among them, the grating spectrometer realizes spatial separation of the incident spectrum through grating interference, but since the infrared detector is expensive and the grating spectrometer requires multiple detectors to measure the interference light, the high cost of the grating interferometer limits its application in the far-infrared working band; the Fourier transform infrared spectrometer uses a moving mirror to control the optical path difference of the two beams of light passing through the beam splitter to produce interference, and processes the signal through Fourier transform to obtain infrared absorption spectrum and other data. Since the moving mirror system requires a certain moving distance, this causes the overall size of the spectrometer to be large, which limits its application in miniature spectrometers. Summary of the invention

[0004] The object of the present invention is to provide a transformation spectrometer based on temperature-dependent reflectivity spectrum, so as to realize the miniaturization of the spectrometer.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The present invention provides a transformation spectrometer based on temperature-dependent reflectivity spectrum. The spectrometer takes temperature as an independent variable, converts the change of the complex refractive index of a thermotropic phase change material in the phase change temperature range into the change of the reflection spectrum of an interference film with temperature, and realizes the function of the spectrometer to measure an unknown incident spectrum by real-time measurement of the reflected light intensity signal during the phase change process and inverting the incident spectrum in combination with the temperature-dependent reflectivity spectrum of the interference film.

[0007] Furthermore, there is a preferred embodiment, the above-mentioned spectrometer specifically includes a light source module, a thermo-induced phase change interference film, a temperature control module, a light intensity acquisition module and a signal processing module;

[0008] The light source module is used to provide an incident light source and inject it into the thermo-induced phase change interference film;

[0009] The temperature control module is used to control the phase change temperature of the interference film;

[0010] Thermotropic interference films are used to adjust the reflection spectrum according to temperature changes;

[0011] The light intensity acquisition module is used to collect the light intensity data of the reflected light of the thermal phase change interference film in real time during the temperature change process;

[0012] The signal processing module is used to collect the temperature controlled by the temperature control module and the reflected light intensity data collected by the light intensity collection module, and is also used to perform inversion calculations on unknown incident spectra based on the collected temperature and reflected light intensity data.

[0013] Furthermore, in a preferred embodiment, the above-mentioned thermo-induced phase change interference film comprises an anti-reflection film, a thermo-induced phase change material, a dielectric layer and a metal substrate;

[0014] The upper and lower layers of the dielectric layer are respectively a thermotropic phase change material and a metal substrate;

[0015] The upper layer of the thermotropic phase change material is an anti-reflection film.

[0016] Furthermore, in a preferred embodiment, the antireflection film is used to improve the transmittance of incident light, resist reflection, and prevent oxidation of the thermotropic phase change material during the phase change process.

[0017] Furthermore, there is another preferred embodiment, through the formula T VO2 =T-QR SiO2 / 基底 Performing temperature calibration on the above-mentioned thermotropic phase change material;

[0018] Where T is the temperature of the lower surface of the spectrometer, Q is the one-dimensional heat flow, and R SiO2 / 基底 is the thermal resistance between the dielectric layer SiO2 and the metal substrate.

[0019] Furthermore, in a preferred embodiment, the phase change temperature range of the above-mentioned thermotropic phase change material is 65-70°C.

[0020] The present invention further provides a method for spectral inversion of a target band of reflected light using a transformation spectrometer based on a temperature-dependent reflectivity spectrum according to any one of the above embodiments, the method comprising:

[0021] Step 1: Control the temperature change of the thermotropic phase change material in the phase change temperature range to obtain a continuous reflectance spectrum data set;

[0022] Step 2: Obtain the reflected light intensity of the external light source through the spectrometer;

[0023] Step 3: Solve the inverse matrix of the light intensity formula of the reflected light intensity according to the reflectance spectrum data set, and invert and solve the spectral distribution of the reflected light intensity.

[0024] Furthermore, in a preferred embodiment, the above-mentioned spectrum inversion method of the target band of reflected light can be stored in a storage system, and the storage system includes:

[0025] A storage device for controlling the temperature change of the thermotropic phase change material in the phase change temperature range to obtain a continuous reflectance spectrum data set;

[0026] A storage device for obtaining the reflected light intensity of an external light source via a spectrometer;

[0027] A storage device for performing an inverse matrix solution on the light intensity formula of the reflected light intensity according to the reflectivity spectral data set, and inverting and solving the spectral distribution of the reflected light intensity.

[0028] The spectral inversion method of the target band of reflected light described in the present invention can be fully implemented by computer software. Therefore, correspondingly, the present invention also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, the spectral inversion method of the target band of reflected light described above is executed.

[0029] The present invention also provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the processor runs the computer program stored in the memory, the processor executes any one of the above-mentioned spectral inversion methods for the target band of reflected light.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention provides a transformation spectrometer based on temperature-dependent reflectivity spectrum. By introducing thermoinduced phase change materials into the structural design of the spectrometer, the optical properties of the thermoinduced phase change materials can be controlled by temperature in the phase change temperature region, and then the thermoinduced phase change materials can be designed as a control function of the spectrometer, that is, the traditional moving mirror control is replaced by the thermoinduced phase change control, thereby realizing the miniaturization of the spectrometer and overcoming the disadvantage of the large size of the traditional spectrometer.

[0032] Furthermore, the present invention is based on the design concept of thermally induced phase change, and can realize the design of a spectrometer with any working band by adjusting conditions such as the selection of dielectric layer materials and the design of film layer structure parameters.

[0033] Furthermore, compared with the prior art, the present invention innovatively proposes a transformation spectrometer design for temperature-dependent reflectivity spectrum, and its control mechanism is based on the property that the optical properties of thermoinduced phase change materials in the phase change transition zone change significantly with temperature. The present invention has a small operating temperature range, can achieve a faster temperature rise or temperature drop process during operation, and obtain the measurement of monitoring data faster. At the same time, the thermoinduced phase change is a change in the phase state of the material, and the complex refractive index changes significantly before and after the phase change, which is more conducive to the design of the spectrometer control and realizes the advantage of obvious changes in optical properties, making it superior in the design of micro-spectrometers.

[0034] Furthermore, compared with the prior art, the current research on the thermotropic phase change material vanadium dioxide mainly focuses on the property changes around the phase change temperature of 68°C, that is, the current research on vanadium dioxide focuses on the two states of high temperature phase and low temperature phase, with the purpose of comparing the properties between two different phases. The present invention proposes a new design idea, mainly studying the phase change temperature range of vanadium dioxide at 65-70°C, using the change of optical properties of vanadium dioxide or thermotropic phase change material during the phase change process to design a temperature-controlled spectrometer, and studying the gradual change of the properties of vanadium dioxide with temperature during the phase change process. Therefore, the present invention belongs to a technical solution different from the prior art concept.

[0035] 2. The spectral inversion method of the target band of reflected light provided by the present invention is based on spectral reconstruction and performs inversion calculation of the unknown incident spectrum by measuring the reflected light intensity signal under temperature changes.

[0036] The invention is applicable to the field of miniaturized spectrometer design. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0038] Figure 1 It is a system schematic diagram of the transformation spectrometer based on temperature-dependent reflectivity spectrum according to the present invention;

[0039] Figure 2 It is a schematic diagram of VO2 temperature calibration in the thermally induced phase change interference film structure of the present invention;

[0040] Figure 3 is a spectrum inversion flow chart of the present invention;

[0041] Figure 4 It is a schematic structural diagram of the near-infrared band thermally induced phase change interference film of the present invention;

[0042] Figure 5 It is the reflection spectrum and working band (dashed line area) of the near-infrared spectrometer of the present invention;

[0043] Figure 6 It is the true value inversion and error analysis of the incident spectrum in the near infrared band of the present invention, wherein Figure (a) is the true value inversion and error analysis of the incident spectrum of a uniform light source, and Figure (b) is the true value inversion and error analysis of the incident spectrum of a sinusoidal light source;

[0044] Figure 7 It is the inversion of quasi-monochromatic light by the temperature-controlled spectrometer in the near-infrared band of the present invention, wherein Figure (a) is the inversion of 1650 / 1654 / 1658 / 1662nm monochromatic light device with a resolution of 4nm in the 1510-1910nm band, and Figure (b) is the inversion of 1650 / 1654 / 1658 / 1662nm quasi-monochromatic light (bandwidth 10nm);

[0045] Figure 8 Schematic diagram of the structure of the far-infrared band thermally induced phase change interference film of the present invention;

[0046] Fig. 9 The interference film reflection spectrum and working band (8-14um) described in the present invention;

[0047] Fig.10 It is a schematic diagram of the reflection spectrum corresponding to some temperatures of the present invention;

[0048] Fig.11 This is the incident spectrum inversion structure and error analysis in the far-infrared band described in the present invention. DETAILED DESCRIPTION

[0049] The specific embodiments of the present invention are further described in detail below in conjunction with the accompanying drawings. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

[0050] Embodiment 1. This embodiment provides a transformation spectrometer based on temperature-dependent reflectivity spectrum. The spectrometer takes temperature as the independent variable, converts the change of the complex refractive index of the thermotropic phase change material in the phase change temperature range into the change of the interference film reflection spectrum with temperature, and realizes the function of measuring unknown incident spectrum by real-time measurement of the reflected light intensity signal during the phase change process and inverting the incident spectrum in combination with the temperature-dependent reflectivity spectrum of the interference film.

[0051] The spectrometer proposed in this embodiment is a spectrometer design based on thermoinduced phase change, that is, by introducing thermoinduced phase change materials into the structural design of the spectrometer device, the optical properties of the thermoinduced phase change materials can be controlled by temperature in the phase change temperature region, and then designed into the regulation function of the spectrometer, that is, replacing the traditional moving mirror regulation by thermal induced phase change regulation, thereby realizing the miniaturization of the spectrometer and overcoming the disadvantage of large size of traditional spectrometers.

[0052] Implementation Method 2: See Figure 1 This embodiment is described. This embodiment is an example of the structure of a transformation spectrometer based on temperature-dependent reflectivity spectrum described in the first embodiment; the spectrometer includes a light source module, a thermotropic phase change interference film, a temperature control module, a light intensity acquisition module and a signal processing module;

[0053] The light source module is used to provide an incident light source and inject it into the thermo-induced phase change interference film;

[0054] The temperature control module is used to control the phase change temperature of the interference film;

[0055] The thermo-induced phase change interference film is used to adjust the reflection spectrum according to temperature changes;

[0056] The light intensity acquisition module is used to collect the light intensity data of the reflected light of the thermal phase change interference film in real time during the temperature change process;

[0057] The signal processing module is used to collect the temperature controlled by the temperature control module and the reflected light intensity data collected by the light intensity collection module, and is also used to perform inversion calculation on the unknown incident spectrum according to the collected temperature and reflected light intensity data.

[0058] In practical application, if Figure 1 As shown, the temperature-controlled spectrometer system includes: a light source module (providing a stable incident light source), a thermo-induced phase change interference film (the reflected spectrum changes with temperature), a temperature control module (including a heater and a thermal resistor for controlling the phase change temperature of the interference film), a light intensity acquisition module (real-time collection of reflected light intensity data during temperature changes), and a signal processing module (inversion calculation of the unknown incident spectrum through the collected temperature and reflected light intensity data).

[0059] Implementation method three, see Figure 2 This embodiment is described. This embodiment is an example of a thermo-induced phase change interference film in a transformation spectrometer based on a temperature-dependent reflectivity spectrum described in the first embodiment.

[0060] The thermo-induced phase change interference film comprises an anti-reflection film, a thermo-induced phase change material, a dielectric layer and a metal substrate;

[0061] The upper and lower layers of the dielectric layer are respectively a thermotropic phase change material and a metal substrate;

[0062] The upper layer of the thermotropic phase change material is an anti-reflection film.

[0063] The interference film structure in the temperature-controlled spectrometer system designed in this embodiment is as follows Figure 2 As shown, it includes anti-reflection film (anti-oxidation layer) / thermotropic phase change material (VO2) / dielectric layer / metal substrate, among which the dielectric layer material can be flexibly selected according to the designed working band: TiO2 / SiO2 / VO2 / SiO2 / Ag structure can be designed near the visible light band; infrared window materials such as ZnSe, Si, SiN, BaF2, etc. can be selected for the design of mid- and far-infrared bands. According to future application requirements, different spectrometers can be realized by adjusting the selection and parameter design of the dielectric layer and thermotropic phase change material to meet various working requirements.

[0064] In actual application, due to the thermal resistance of each film layer, the temperature of the VO2 layer in the middle of the film layer cannot be directly measured and needs to be calibrated. The following are the measurement results of the temperature-controlled spectrometer: (1) The thickness of the VO2 film layer is 130nm, and its temperature field is uniform, that is, the upper and lower surface temperatures are equal; (2) The upper and lower surface temperatures T0 and T of the device can be measured by RTD (resistance temperature detector); the one-dimensional heat flow Q can be measured by a heat flow meter; (3) By measuring the SiO2 / metal substrate structure with the same structural parameters separately, its thermal resistance R SiO2 / 基底 Therefore, the VO2 temperature is calibrated: T VO2 =T-QR SiO2 / 基底 .

[0065] Implementation method 4: See Figure 3 This embodiment is described. This embodiment provides a spectrum inversion method of a target band of reflected light implemented by a transformation spectrometer based on a temperature-dependent reflectivity spectrum. The inversion method is:

[0066] This implementation method takes into account the absorption problem of vanadium dioxide (VO2), adds a metal substrate and designs the film layer with reflectivity as the system research object, and studies the regulation of radiation characteristics under different structural parameters. The radiation characteristics are studied by the transfer matrix method and the time domain finite difference method, and the dynamic regulation of filtering is studied by using the characteristic of temperature regulation of radiation characteristics. The specific method is as follows: Figure 3 As shown,

[0067] Step 1: Control the temperature change of the thermotropic phase change material in the phase change temperature range to obtain a continuous reflectance spectrum data set;

[0068] Step 2: Obtain the reflected light intensity of the external light source through the spectrometer;

[0069] Step 3: Solve the inverse matrix of the light intensity formula of the reflected light intensity according to the reflectance spectrum data set, and invert and solve the spectral distribution of the reflected light intensity.

[0070] In practical application, if Figure 3 As shown, by optimizing the design of the resonant cavity device, continuous reflectivity data [r(λ,T)] that varies with temperature can be obtained, and the reflected light intensity [IR(T)] of the external light source through the resonant cavity device can be measured by the corresponding optical element. By solving the inverse matrix of the reflected light intensity formula [IR(T)] = [r(λ,T)] × [I0(λ)], the spectral distribution of the incident light intensity [I0(λ)] can be inverted and solved. That is, the original data set required for the inversion of the computational spectrometer is obtained by temperature control of the vanadium dioxide resonant cavity device, and the inversion of the unknown incident spectral distribution is realized. In the phase change temperature range, the optical constants of vanadium dioxide (VO2) are changed by temperature change, and then the optical path difference of the incident light in the dielectric layer is controlled to achieve the effect of spectral regulation.

[0071] The specific spectrum inversion related formula is as follows:

[0072] Compared with the traditional spectrometer that directly measures the intensity of each wavelength, the transformation spectrometer measures the light intensity signal processed by the interference film, that is, the coded version of the spectrum. By adjusting the reflection spectrum of the interference film, the measured reflected light intensity signal changes accordingly, and it can be decoded by calculation, that is, the incident spectrum inversion calculation.

[0073]

[0074] in, λ is the wavelength, IR(T) is the reflected light intensity measured with temperature change during phase change, r(T, λ ) is the temperature-dependent reflectivity spectrum of the interference film, and I0(λ) is the unknown incident spectrum to be measured. It can also be written in matrix form:

[0075] b=M×A

[0076] Among them, A represents the one-dimensional column vector of the n spectral channels of the input signal, in which the ath element A(a) represents the intensity of the wavelength λa in the incident light source; b represents the one-dimensional vector of the m temperature channels of the output signal, which actually represents the real-time measurement of the reflected light intensity during the phase change process; M represents the temperature-dependent reflectivity spectrum data of the interference film designed according to work needs. Since the design parameters of the interference film are known, that is, the coefficient matrix M is known, an incident light of an unknown spectrum is incident on the transformation spectrometer system, and the detector collects the real-time signal of the reflected light intensity changing with temperature during the phase change process, so b is also known. Therefore, spectral inversion is to calculate A based on M and b.

[0077] Considering that the results of the reflectance spectrum at adjacent temperatures may have strong linear correlation in some bands, this may easily cause the condition number of the coefficient matrix of the inversion equation to be too large, resulting in the equation being ill-conditioned and unable to obtain accurate incident light intensity results. Therefore, in programming, the method of singular value decomposition (SVD) and deleting the smallest singular value is used to reduce the degree of ill-conditioning of the inversion equation. The core is to express the coefficient matrix M representing the temperature-dependent reflectance spectrum as the product of the following three real matrices, that is, to factorize the matrix:

[0078] M=UΣV T

[0079] Wherein, U is an m-order orthogonal matrix, V is an n-order orthogonal matrix, and ∑ is an m×n rectangular diagonal matrix consisting of non-negative diagonal elements arranged in descending order.

[0080] Implementation method 5: See Figures 4 to 11 This embodiment is described. This embodiment is an example of a transformation spectrometer based on temperature-dependent reflectivity spectrum described in the above embodiment.

[0081] This embodiment is based on the design concept of thermally induced phase change. By adjusting conditions such as the selection of dielectric layer materials and the design of film layer structure parameters, the design of a spectrometer with any working band can be realized.

[0082] For example: designing TiO2 / SiO2 / VO2 / SiO2 / Ag structure as interference film structure scheme for spectrometer in near infrared (1510~1920nm) working band, such as Figure 4 As shown. TiO2 / SiO2 is used as an oxidation protection layer and anti-reflection film for vanadium dioxide VO2, and the thickness of the TiO2 / SiO2 / VO2 / SiO2 film layers are 35nm / 579nm / 80nm / 2um respectively. The bottom of the device is a metal substrate to achieve spectral reflection and uniform heating of the device. Silver is used as the metal layer, silicon dioxide SiO2 is the intermediate medium, and vanadium dioxide VO2 forms a Fabry-Perot (FP) resonant cavity. Taking temperature as the independent variable, the change of the complex refractive index of vanadium dioxide VO2 in the phase change temperature range is converted into the optical path difference / phase difference of the interference of the incident light, so as to realize the regulation of the interference of the incident light. Among them, the phase change temperature range is 65-70℃. Through transmission matrix programming simulation, it can be observed that Figure 5There are four resonance peaks in the reflectivity image in the 1-4um band as shown. As the temperature rises, the wavelengths corresponding to the peaks and valleys of the reflection spectrum (spectral absorption peaks) shift significantly, while the resonance peaks do not shift significantly. The four reflection resonance peaks appear near wavelengths of 1200nm, 1500nm, 2000nm and 2850nm, respectively. The three absorption peaks shift significantly in the process of temperature increase, and the corresponding troughs in the reflectivity image also change accordingly. Due to the effect of the metal reflective substrate, the transmittance of the spectrometer is zero, so the reflectivity and absorptivity are basically complementary, that is, the absorption of silicon dioxide and metal layers is relatively small compared to the absorption of vanadium dioxide during the radiation interference process, and can be ignored in the subsequent radiation characteristic analysis.

[0083] In the design of temperature-controlled spectrometer, the following Figure 5 The 1510-1920 nm band shown is studied as the working band. This band is located between the second and third resonance peaks of the reflection spectrum. The reflection peak and valley shift significantly with temperature changes. In the subsequent incident light inversion calculation, the morbidity of the inversion coefficient matrix can be greatly reduced, thereby improving the inversion accuracy.

[0084] In the inversion calculation of the incident light intensity, this embodiment adopts the matrix inversion operation, in which the spectral reflectivity of the device and the measured reflected light intensity are used as known parameters to solve the incident light intensity. By interpolating the optical parameters of vanadium dioxide (VO2) in the phase change temperature range, 0.05°C is selected as the interval to obtain 101 sets of original parameters. Through the transfer matrix method simulation, its reflection spectrum [r(λ,T)] at the corresponding temperature can be obtained, and the incident light intensity [IR(T)] can be measured by the corresponding optical measurement element in practical applications. In the calculation of the inversion program, this embodiment calculates the reflected light intensity by the formula assuming the incident light intensity, and uses it as an input parameter to study the error accuracy of the true value inversion during the matrix inversion operation.

[0085] Considering that the results of the reflection spectrum at adjacent temperatures may have strong linear correlation in some bands, this may easily cause the condition number of the coefficient matrix of the inversion equation to be too large, resulting in the equation being ill-conditioned and unable to obtain accurate incident light intensity results. Therefore, in programming, the method of singular value decomposition (SVD) and deleting the smallest singular value is used to reduce the degree of ill-conditioning of the inversion equation, and the inversion accuracy in each band is analyzed to determine the working wavelength of the device.

[0086] The 1510-1920nm band is selected for incident light intensity inversion to verify the influence of the working band selection and the corresponding band of the reflection peak on the error. This embodiment uses two types of incident light, a uniform light source and a sinusoidal light source, to analyze the inversion results. Figure 6It can be found that after eliminating the influence of the linear correlation of the reflection peak position, the inversion error is greatly reduced. In this band, the relative error is generally less than 0.01%, which can achieve a good incident light intensity inversion effect and the incident spectrum true value inversion accuracy is very high.

[0087] In addition, this embodiment performs relevant analysis on the quasi-monochromatic light inversion effect, such as Figure 7 As shown, the results show that the spectral resolution of the present invention is 4nm in the working band of 1510-1920nm, and at the same time, the inversion accuracy of quasi-monochromatic light with a bandwidth of 10nm is relatively high, and it has superior performance.

[0088] Another example: designing Si / ZnSe / Si / ZnSe / VO2 / ZnSe / metal substrate structure as interference film structure scheme for far infrared (8-14um) working band: considering the absorption of mid- and far-infrared light by some materials, this scheme selects ZnSe and Si as infrared window materials for design: Si and ZnSe have the characteristics of high transparency and low absorption rate in the mid- and far-infrared bands, and use them as interference film dielectric layer materials to study the performance of temperature-controlled spectrometers with interference film structures in the mid- and far-infrared. Thermo-induced phase change interference film consists of two parts, such as Figure 8 As shown: 1. Anti-reflection film (high and low refractive index materials are stacked periodically

[0089] 130nmSi / 86nmZnSe / 130nmSi / 86nmZnSe), which plays a role in improving the transmittance of incident light, anti-reflection, and preventing VO2 from oxidizing during the phase change process; 2.FP resonant cavity (130nmVO2 / 3000nmZnSe / metal substrate), the FP resonant cavity has the characteristics of a broadband working range and can be designed for multiple wavelength analysis; at the same time, its simple structure also facilitates the processing of the device.

[0090] First, a broadband analysis of the interference film reflection spectrum is performed, such as Fig. 9 As shown, the results show that: under the action of the resonant cavity, the reflection spectrum has multiple resonance peaks and the wavelength interval between the resonance peaks gradually increases along the wavelength direction; in the band between the two resonance peaks, the peak and valley of the reflection spectrum shift in the wavelength direction with temperature changes. This is because the refractive index of the VO2 material changes due to temperature changes, and the absorption of the incident light by the FP resonant cavity structure also changes accordingly; the reflection spectrum at different temperatures is the subsequent incident spectrum, such as Fig.10 As shown, the inversion provides the original data source, and the inversion resolution of the temperature-controlled spectrometer can be controlled by controlling the temperature interval in the reflected light intensity measurement.

[0091] The reflected light intensity data is detected at a temperature interval of 0.05°C, and the 8-14um band is inverted and calculated, such as Fig.11As shown, the results show that the inversion result is roughly consistent with the incident spectrum, with a relative error within ±3%, which can achieve a good incident light intensity inversion effect and a high accuracy of incident spectrum true value inversion. The resolution of the temperature-controlled spectrometer in this band is 59nm.

[0092] Embodiment 6. The spectral inversion method of the target band of reflected light described in the above embodiments can be fully implemented by computer software. Therefore, correspondingly, this embodiment provides a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, the spectral inversion method of the target band of reflected light described above is executed.

[0093] Embodiment 7: This embodiment provides a computer device, which includes a memory and a processor, wherein the memory stores a computer program. When the processor runs the computer program stored in the memory, the processor executes any one of the above-mentioned methods for spectral inversion of a target band of reflected light.

[0094] A computer device is provided in this embodiment. The hardware device of this part is a general model and is not shown in the form of a diagram. The system includes a processor and a memory, wherein the processor and the memory can be connected via a bus or other means. The memory is a non-transitory computer-readable storage medium that can be used to store non-transitory software programs, non-transitory computer executable programs and modules, and corresponding program instructions / modules. The processor executes various functional applications and data processing of the processor by running the non-transitory software programs, instructions and modules stored in the memory, so as to realize the spectral inversion method and steps of the target band of reflected light in the above method embodiment.

[0095] In the description of this specification, thermotropic phase change material refers to a material whose optical properties change significantly with temperature, and has the following characteristics: (a) phase reversibility, amorphous state can be transformed into crystalline state by heat or solar energy, and crystalline state can be transformed into amorphous state by quenching or cooling. The conversion between crystalline state and amorphous state and the degree of crystallization can reflect the change of effective dielectric constant of the material itself; (b) any intermediate phase can be obtained, usually heating at the same heating temperature for different time or applying different heating temperature at the same heating time can obtain the required intermediate phase; (c) stability, that is, most phase change materials can ensure that they are not easy to volatilize or be oxidized by air at room temperature in any phase; (d) fast response characteristics, there are many types of excitation sources for phase change materials, but the speed of phase change response is very fast. By utilizing the properties of thermotropic phase change, the optical properties of the material can be controlled by temperature in the phase change temperature region, and then it can be designed into the regulation function of the spectrometer.

[0096] The above description is only the implementation mode of the present invention and is not limited to the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A transformation spectrometer based on temperature-dependent reflectivity spectrum, characterized in that: The spectrometer takes temperature as the independent variable and converts the change of the complex refractive index of the thermoinduced phase change material in the phase change temperature range into the change of the interference film reflection spectrum with temperature. It also inverts the incident spectrum by real-time measuring the reflected light intensity signal during the phase change process and combining it with the temperature-dependent reflectivity spectrum of the interference film, thereby realizing the spectrometer's function of measuring unknown incident spectra.

2. The transformation spectrometer based on temperature-dependent reflectivity spectrum according to claim 1 is characterized in that: The spectrometer includes a light source module, a thermo-induced phase change interference film, a temperature control module, a light intensity acquisition module and a signal processing module; The light source module is used to provide an incident light source and inject it into the thermo-induced phase change interference film; The temperature control module is used to control the phase change temperature of the interference film; Thermotropic interference films are used to adjust the reflection spectrum according to temperature changes; The light intensity acquisition module is used to collect the light intensity data of the reflected light of the thermal phase change interference film in real time during the temperature change process; The signal processing module is used to collect the temperature controlled by the temperature control module and the reflected light intensity data collected by the light intensity collection module, and is also used to perform inversion calculations on unknown incident spectra based on the collected temperature and reflected light intensity data.

3. The transformation spectrometer based on temperature-dependent reflectivity spectrum according to claim 2 is characterized in that: The thermo-induced phase change interference film comprises an anti-reflection film, a thermo-induced phase change material, a dielectric layer and a metal substrate; The upper and lower layers of the dielectric layer are respectively a thermotropic phase change material and a metal substrate; The upper layer of the thermotropic phase change material is an anti-reflection film.

4. The transformation spectrometer based on temperature-dependent reflectivity spectrum according to claim 3 is characterized in that: The anti-reflection film is used to increase the transmittance of incident light, resist reflection, and prevent oxidation of the thermoinduced phase change material during the phase change process.

5. The transformation spectrometer based on temperature-dependent reflectivity spectrum according to claim 4 is characterized in that: By formula T VO2 =T-QR SiO2 / 基底 Temperature calibration of thermotropic phase change materials; Where T is the temperature of the lower surface of the spectrometer, Q is the one-dimensional heat flow, and R SiO2 / 基底 is the thermal resistance between the dielectric layer SiO2 and the metal substrate.

6. The transformation spectrometer based on temperature-dependent reflectivity spectrum according to claim 3 is characterized in that: The phase change temperature range of the thermotropic phase change material is 65-70°C.

7. The method for spectral inversion of a target band of reflected light implemented by a transformation spectrometer based on a temperature-dependent reflectivity spectrum according to any one of claims 1 to 6, characterized in that: The method is: Step 1: Control the temperature change of the thermotropic phase change material in the phase change temperature range to obtain a continuous reflectance spectrum data set; Step 2: Obtain the reflected light intensity of the external light source through the spectrometer; Step 3: Solve the inverse matrix of the light intensity formula of the reflected light intensity according to the reflectance spectrum data set, and invert and solve the spectral distribution of the reflected light intensity.

8. The method for spectral inversion of a target band of reflected light according to claim 7 is characterized in that: The inversion method is stored in a storage system, which includes: A storage device for controlling the temperature change of the thermotropic phase change material in the phase change temperature range to obtain a continuous reflectance spectrum data set; A storage device for obtaining the reflected light intensity of an external light source via a spectrometer; A storage device for performing an inverse matrix solution on the light intensity formula of the reflected light intensity according to the reflectivity spectral data set, and inverting and solving the spectral distribution of the reflected light intensity.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the method for spectral inversion of a target wavelength band of reflected light as claimed in claim 8 is executed.

10. A computer device, characterized in that: The device comprises a memory and a processor, wherein a computer program is stored in the memory, and when the processor runs the computer program stored in the memory, the processor executes the spectral inversion method of the target wavelength band of reflected light as claimed in claim 8.

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