Spectral measurement method based on spectrometer, electronic device and computer readable medium

Abstract

The present application discloses a spectrum measurement method based on a spectrometer, an electronic device and a computer-readable medium. The spectrometer includes a cascaded optical filter and a measuring device. The optical filter includes a cascaded beam splitter, a filter array and an incoherent adder. The filter array includes a plurality of filter units, and each filter unit is provided with a phase modulator; the phase modulation rate of each filter unit is determined according to the optical filtering frequency of each filter unit; the determined multiple phase modulation rates are output to the corresponding phase modulators respectively, and the incident light is input to the beam splitter so that the phase modulator modulates the light passing through the corresponding filter unit according to the phase modulation rate; the spectrum measurement information output by the measuring device is obtained; the beam splitter divides the incident light into equal parts and inputs it to each filter unit, the incoherent adder performs incoherent addition on the output light of each filter unit, and the measuring device determines the spectrum measurement information based on the output light of the incoherent adder.

Description

Technical Field

[0001] The present application relates to the field of spectral technology, and in particular to a spectral measurement method based on a spectrometer, an electronic device and a computer-readable medium. Background Art

[0002] Spectroscopic analysis is a technique that uses the spectrum generated when matter interacts with electromagnetic radiation to study matter. It determines the nature, structure or composition of matter by analyzing the spectral characteristics of matter such as absorption, emission or scattering of light. Spectroscopic analysis has many advantages such as high accuracy, high sensitivity, simple and fast operation, etc. Therefore, it is widely used in biochemistry, metal materials, chemical analysis, astrophysics, biopharmaceuticals, environmental monitoring, physical and chemical testing and other fields. It has unique advantages in the identification of compounds, control of chemical processes, determination of molecular structure, qualitative and quantitative chemical analysis, etc.

[0003] A spectrometer is an instrument used for spectral analysis. Traditional desktop spectrometers mainly include spectroscopic spectrometers based on dispersion prisms or narrowband filters and Fourier transform spectrometers based on Michelson interferometers, which usually have higher resolution, larger spectral range, higher sensitivity and more precise wavelength accuracy. In addition, desktop spectrometers usually have more spectral analysis functions and scalable analysis capabilities to meet more complex analysis needs. However, although traditional desktop spectrometers are precise and expensive instruments, they have strict requirements on working environment conditions (temperature, humidity, vibration, electromagnetic interference, and the professionalism of analysts, etc.), and are bulky and not portable. They cannot be tested on site, and the test target must be determined first, and then the samples must be brought into the laboratory for testing.

[0004] With the global development situation, there has been a strong demand for miniaturization, portability and on-site operation of spectrometers in this field since the late last century, and the miniaturization of spectrometers has become a development trend. On-chip spectrometers are an important technological innovation in the process of miniaturization of spectrometers. They have application value in the fields of smart medical care, geological exploration, and lab-on-a-chip, especially for realizing miniaturized, portable, and even wearable smart sensing devices. On-chip spectrometers are based on integrated photonic circuit technology, integrating various optical devices on a chip-scale plane. These optical devices are usually composed of solid-state planar waveguides, which can achieve dense integration on a chip scale and eliminate the influence of environmental disturbances.

[0005] Traditional on-chip Fourier spectrometers can be divided into two categories: spatial modulation and time modulation according to the modulation measurement method of Fourier spectrum information. However, traditional spatial modulation on-chip Fourier spectrometers can only be used for rough analysis of the spectral components of optical fiber signals, and traditional time modulation on-chip Fourier spectrometers have the problems of long adjustment and calculation time and poor immediacy.

[0006] Therefore, there is an urgent need for a spectral measurement method that can simultaneously solve the problems of both spatial modulation and temporal modulation on-chip Fourier spectrometers. Summary of the invention

[0007] The present application aims to solve one of the technical problems in the related art to a certain extent. To this end, the present application provides a spectrum measurement method based on a spectrometer, an electronic device and a computer readable medium.

[0008] As a first aspect of the present application, a spectrum measurement method based on a spectrometer is provided, wherein the spectrometer includes a cascaded optical filter and a measuring device, the optical filter includes a cascaded beam splitter, a filter array and an incoherent adder, the filter array includes a plurality of filter units, and each of the filter units is provided with a phase modulator; the method includes:

[0009] Determining a phase modulation rate of each filter unit according to the optical filtering frequency of each filter unit;

[0010] Outputting the determined multiple phase modulation rates to corresponding phase modulators respectively, and inputting the incident light to the beam splitter, so that each phase modulator modulates the light passing through the corresponding filter unit according to each phase modulation rate respectively;

[0011] Acquire spectral measurement information output by the measuring device; wherein the beam splitter divides the incident light into equal parts and inputs them into each of the filter units, the incoherent adder performs incoherent addition on the output light of each of the filter units, and the measuring device determines the spectral measurement information based on the output light of the incoherent adder.

[0012] Optionally, the measuring device collects light generated after the output light of the incoherent adder passes through a sample object to determine the spectral measurement information.

[0013] Optionally, the phase modulation rate of the filter unit is proportional to its optical filtering frequency.

[0014] Optionally, each of the phase modulators provides a periodic phase modulation amount to the light passing through the corresponding filter unit according to each phase modulation rate, and the period length of the phase modulation amount is 2π.

[0015] As a second aspect of the present application, an electronic device is provided, wherein the electronic device includes:

[0016] one or more processors;

[0017] A memory having one or more computer programs stored thereon, when the one or more computer programs are executed by the one or more processors, enables the one or more processors to implement the spectrometer-based spectral measurement method provided according to the first aspect of the present application.

[0018] As a third aspect of the present application, a spectrum measurement system is provided, wherein the spectrum measurement system comprises the electronic device provided according to the second aspect of the present application and a spectrometer, the spectrometer comprises a cascaded optical filter and a measuring device, the optical filter comprises a cascaded beam splitter, a filter array and an incoherent adder, the filter array comprises a plurality of filter units, each of the filter units is provided with a phase modulator;

[0019] The beam splitter is used to divide the incident light into equal parts and input them into each of the filter units; the phase modulator is used to modulate the light passing through the corresponding filter unit according to the phase modulation rate; the incoherent adder is used to incoherently add the output light of each of the filter units; and the measuring device is used to determine the spectral measurement information based on the output light of the incoherent adder.

[0020] Optionally, the filter unit is an asymmetric Mach-Zehnder interferometer, and the filter array is composed of a plurality of the asymmetric Mach-Zehnder interferometers connected in parallel, in series, or in a combination of series and parallel.

[0021] Optionally, the measuring device is used to collect light generated after the output light of the incoherent adder passes through a sample object, so as to determine the spectral measurement information.

[0022] Optionally, the phase modulation rate of the filter unit is proportional to its optical filtering frequency.

[0023] As a fourth aspect of the present application, a computer-readable medium is provided, on which a computer program is stored, wherein when the computer program is executed by a processor, the spectrometer-based spectral measurement method provided according to the first aspect of the present application is implemented.

[0024] In the spectral measurement method based on a spectrometer provided in the embodiment of the present application, the spectrometer used includes a cascaded optical filter and a measuring device, the optical filter includes a cascaded beam splitter, a filter array and an incoherent adder, the filter array includes a plurality of filter units, and each filter unit is provided with a phase modulator; first, according to the optical filtering frequency of each filter unit, the phase modulation rate of each filter unit is determined, and the determined multiple phase modulation rates are respectively output to the corresponding phase modulator, and the incident light is input to the beam splitter, the beam splitter divides the incident light into equal parts and inputs it to each filter unit, each phase modulator modulates the light passing through the corresponding filter unit according to each phase modulation rate, the incoherent adder performs incoherent addition on the output light of each filter unit, and the measuring device determines the spectral measurement information based on the output light of the incoherent adder. The spectral information of the incident light in the spectrum to be measured can be directly projected into the time domain without the need for an additional solution algorithm, thereby reducing the demand for photodetectors, simplifying the process of spectral measurement, shortening the spectral measurement time, improving the spectral measurement efficiency, and realizing the instant measurement of spectral information. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present application is further described below in conjunction with the accompanying drawings:

[0026] Figure 1 It is a flow chart of an implementation of a spectrum measurement method based on a spectrometer provided in an embodiment of the present application;

[0027] Figure 2 is a schematic diagram of an optical filter provided in an embodiment of the present application;

[0028] Figure 3 is a schematic diagram of a measurement method provided in an embodiment of the present application;

[0029] Figure 4 is a schematic diagram of another measurement method provided in an embodiment of the present application;

[0030] Figure 5 is a schematic diagram of an implementation of an electronic device provided in an embodiment of the present application;

[0031] Figure 6 It is a schematic diagram of a computer-readable medium provided in an embodiment of the present application.

[0032] Description of Reference Numerals

[0033] 101: Processor 102: Memory

[0034] 103: I / O interface 104: bus DETAILED DESCRIPTION

[0035] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments based on the embodiments are intended to be used to explain the present application and cannot be understood as limiting the present application.

[0036] References to "one embodiment" or "an example" or "an example" in this specification mean that a particular feature, structure, or characteristic described in conjunction with the embodiment itself may be included in at least one embodiment disclosed in the present application. The appearance of the phrase "in one embodiment" in various places in the specification does not necessarily refer to the same embodiment.

[0037] In a traditional spatial modulation on-chip Fourier transform spectrometer, the light transmitted into the on-chip waveguide system is sent to the filter array through a branch path, and the spectrum sequence of the incident light is independently extracted through each filter unit, and the spectrum information is spatially modulated by a branch path, and then sent to an independent photodetector (PD) for measurement. For example, an existing on-chip Fourier transform spectrometer based on a double-layer spiral waveguide uses the group refractive index difference between the odd mode and the even mode in the double-layer waveguide to form a non-equal-arm Mach-Zehnder interferometer (MZI) interferometer structure, and uses N double-layer spiral waveguides with increasing lengths to realize a spatial heterodyne coherence-based Fourier transform spectrometer, and the measured interference fringes are reconstructed by a regression algorithm to realize the spectrum.

[0038] The output mode of the traditional spatial modulation on-chip Fourier spectrometer determines the singleness of its measurement mode. Since it is necessary to first obtain the intensity information of the output light of each interferometer and then obtain the spectral information through inverse Fourier transform, if the sample to be tested is placed at the output end of each interferometer, the output light of each interferometer will affect each other and it is impossible to obtain accurate intensity information of each. Therefore, the sample to be tested can only be set at the front end of the on-chip Fourier spectrometer, and the single-mode optical input port of the on-chip spectrometer does not have the ability to collect and couple scattered light. Therefore, this type of spectrometer can only be used for spectral measurement in single-mode optical fiber (waveguide) systems, and rarely leaves the laboratory to enter the field of practical spectral measurement.

[0039] The traditional time-modulated on-chip Fourier spectrometer, through the mechanical scanning of the interferometer moving mirror, makes the optical path difference between the two interference optical paths of the interferometer change continuously, records the light and dark changes of the central interference fringes, that is, the function curve interference diagram between light intensity and time, and then performs Fourier transform on it to measure the spectrum diagram. For example, an existing Fourier transform spectrometer based on on-chip optical switch and delay line array cascades the optical switch array on the two arms of MZI to achieve large-scale, high-precision Fourier spectrum phase shift control. Another example is another existing silicon-based on-chip Fourier transform spectrometer and method for obtaining light source reconstructed spectrum, through the combination of optical path digital gating technology of optical switch and non-equal arm sub-wavelength grating waveguide pair, a series of non-equal arm MZI arrays with different optical path differences are realized, and the resolution of the chip is effectively improved through compressed sampling technology and spectrum reconstruction algorithm.

[0040] Although the traditional time-modulated on-chip Fourier spectrometer does not have the coupling problem, this type of spectrometer is a single-channel device in space. The optical path differences of the interferometer required for Fourier spectral analysis are achieved through optical path adjustment, which requires a long scanning time. The complete Fourier spectrum is then obtained by performing an inverse Fourier transform on the light intensity information after interference of each optical path difference. The excessive time consumption and spectral bandwidth limitation also make it difficult for this type of spectrometer to enter the practical field.

[0041] In view of this, the applicant of the present application proposes that by adding a phase modulator to the filter unit to modulate the light passing through the filter unit, the filter unit can modulate the light in the time domain while performing optical filtering. Furthermore, by incoherently superposing the output light of each filter unit in a light intensity superposition manner (incoherent superposition), the spectral information of the incident light in the spectral band to be measured can be periodically projected into the time domain. Ultimately, the spectral measurement information can be obtained based on the incoherently superimposed output light.

[0042] As a first aspect of an embodiment of the present application, a spectrum measurement method based on a spectrometer is provided, wherein the spectrometer includes a cascaded optical filter and a measuring device, the optical filter includes a cascaded beam splitter, a filter array and an incoherent adder, the filter array includes a plurality of filter units, and each of the filter units is provided with a phase modulator; Figure 1 As shown, the method may include:

[0043] In step S110, the phase modulation rate of each filter unit is determined according to the optical filtering frequency of each filter unit;

[0044] In step S120, the determined multiple phase modulation rates are output to corresponding phase modulators respectively, and the incident light is input to the beam splitter, so that each phase modulator modulates the light passing through the corresponding filter unit according to each phase modulation rate;

[0045] In step S130, the spectral measurement information output by the measuring device is obtained; wherein the beam splitter divides the incident light into equal parts and inputs them into each of the filter units, the incoherent adder performs incoherent addition on the output light of each of the filter units, and the measuring device determines the spectral measurement information based on the output light of the incoherent adder.

[0046] In the embodiment of the present application, the beam splitter included in the pre-constructed optical filter may be a 1*N beam splitter. Figure 2 As shown, it is a schematic diagram of an optical filter provided in an embodiment of the present application. The optical filter may include a cascaded 1*N beam splitter, a filter array and an incoherent adder. The filter array may include a plurality of filter units, each of which is provided with a phase modulator ( Figure 2 The optical filter may also be called a Fourier transformer and may be a system-on-chip.

[0047] The embodiment of the present application is based on a traditional spatial modulation on-chip Fourier spectrometer. By adding a phase modulator to each filter unit, the filter unit can modulate light in the time domain while performing optical filtering. By cascading an incoherent adder after the filter array, the incoherent adder can periodically project the spectral information of the incident light in the spectral band to be measured into the time domain.

[0048] In the embodiment of the present application, the spectrometer includes a cascaded optical filter and a measuring device, that is, the spectrometer includes an optical filter and a measuring device and the optical filter is located before the measuring device. The measuring device cascaded after the optical filter is not specifically limited. For example, the measuring device can be a device that uses photoelectric conversion means to record, transmit and process the spectrum in the form of an electrical signal, such as a light information sampling circuit, a personal computer (Personal Computer, PC) / microcontroller unit (Microcontroller Unit, MCU) / control calculation module, etc. The measuring device can also be a device that uses other means of converting light intensity to directly record the spectrum on other media, such as a device that directly performs photolithography recording using photochemical action, or converts light signals into temperature signals using photothermal effects. It can be seen that the measuring device can be other devices other than photodetectors, and is no longer limited to photodetectors, which can reduce the demand for photodetectors.

[0049] It can be understood that the spectrometer can also include an on-chip optical filter driving module, which can drive the optical filter through common methods such as constant current, constant voltage, constant power and pulse width modulation (PWM) under the control of the above-mentioned PC / MCU / control computing module.

[0050] In the spectral measurement method based on a spectrometer provided in the embodiment of the present application, the spectrometer used includes a cascaded optical filter and a measuring device, the optical filter includes a cascaded beam splitter, a filter array and an incoherent adder, the filter array includes a plurality of filter units, and each filter unit is provided with a phase modulator; first, according to the optical filtering frequency of each filter unit, the phase modulation rate of each filter unit is determined, and the determined multiple phase modulation rates are respectively output to the corresponding phase modulator, and the incident light is input to the beam splitter, the beam splitter divides the incident light into equal parts and inputs it to each filter unit, each phase modulator modulates the light passing through the corresponding filter unit according to each phase modulation rate, the incoherent adder performs incoherent addition on the output light of each filter unit, and the measuring device determines the spectral measurement information based on the output light of the incoherent adder. The spectral information of the incident light in the spectrum to be measured can be directly projected into the time domain without the need for an additional solution algorithm, thereby reducing the demand for photodetectors, simplifying the process of spectral measurement, shortening the spectral measurement time, improving the spectral measurement efficiency, and realizing the instant measurement of spectral information.

[0051] As described above, in the conventional spatial modulation on-chip Fourier spectrometer, the sample to be measured can only be set at the front end thereof, while the sample to be measured can not only be set at the front end of the spectrometer, but also be measured using the spectrometer provided in the present application.

[0052] In the embodiment of the present application, the optical filter can be directly used to independently analyze the spectral light source to be measured, that is, the incident light can be the spectral light source to be measured, and the proposed spectrometer can be directly used to perform spectral measurement on the spectral light source to be measured, and the measuring device directly collects the output light of the incoherent adder, and directly determines the spectral measurement information of the spectral light source to be measured based on the output light of the incoherent adder. The optical filter can also modulate the wide-spectrum light source and irradiate it onto the sample and then perform spectral measurement on the generated reflected light / transmitted light, that is, the incident light can also be a wide-spectrum light source, and unlike the traditional spatial modulation type on-chip Fourier spectrometer, in the embodiment of the present application, the sample object can also be set at the rear end of the spectrometer, and accordingly, the measuring device can collect the reflected light / transmitted light generated by the output light of the incoherent adder after passing through the sample object, and determine the measurement information of the reflected spectrum / transmitted spectrum based on the reflected light / transmitted light.

[0053] Accordingly, in some embodiments, the measuring device collects light generated after the output light of the incoherent adder passes through the sample object to determine the spectral measurement information.

[0054] Figure 3 and Figure 4 Schematic diagram of two different measurement methods provided in the embodiment of the present application, taking a spectrometer including an optical filter, an on-chip optical filter driving module, an optical information sampling circuit and a PC / MCU / control computing module as an example, Figure 3 As shown, the incident light input to the optical filter can be a wide-spectrum light source, and the light information sampling circuit and the PC / MCU / control calculation module measure the reflection spectrum / transmission spectrum generated by the output light of the optical filter irradiating the sample. Figure 4 As shown, the incident light input to the optical filter can be the spectral light source to be measured, and the optical information sampling circuit and the PC / MCU / control calculation module measure the spectrum of the output light of the optical filter, that is, directly measure the spectrum of the incident light.

[0055] In addition, in the embodiments of the present application, there is no special limitation on how to input the incident light into the beam splitter. For example, the incident light can be coupled into the beam splitter of the optical filter via a waveguide input coupler (such as an end face coupler structure or a grating coupler structure).

[0056] In some embodiments, the phase modulation rate of the filter unit is proportional to its optical filtering frequency.

[0057] In addition, considering that the phase modulation range may be limited in practical applications, the phase modulation amount can also be periodically provided in the range of [0-2π] according to the phase modulation rate. Accordingly, in some embodiments, each of the phase modulators provides a periodic phase modulation amount to the light passing through the corresponding filter unit according to each of the phase modulation rates, and the period length of the phase modulation amount is 2π.

[0058] The method of periodically providing the phase modulation amount in the range of [0-2π] has the same effect as the above-mentioned method of continuous modulation according to the phase modulation rate, and is more feasible in engineering.

[0059] The implementation principle of the traditional spatial modulation on-chip Fourier spectrometer is as follows: the incident light is equally divided into each Fourier spectrum component analysis unit (i.e., filter unit) of the filter array through a 1*N beam splitter, and the optical filtering frequency of each filter unit is Different, the optical filtering frequency of the entire filter array The range covers the main range of the Fourier transform spectrum of the incident light, and the optical filtering frequency of each filter unit Corresponding to one of the frequencies in the Fourier transform spectrum of the incident light The incident light is equally divided into the i-th filter unit and passes through the filter unit OF i Filter out frequencies that do not meet the optical filter frequency The Fourier transform spectrum of the incident light is proportional to the frequency The output light intensity I i At this point, the optical architecture of the traditional spatial modulation on-chip Fourier spectrometer has been completed, and it is only necessary to record the output light intensity I of each filter unit. i , and then use photoelectric conversion to form a light intensity sequence proportional to the Fourier transform spectrum of the incident light (Among them, P FFT (…) represents fast Fourier transform), and finally the light intensity sequence is calculated based on the related algorithm of inverse Fourier transform, thus completing the whole process of spectral measurement and solution, and obtaining the spectral measurement information P(λ) of the incident light.

[0060] The applicant of the present application proposes that, based on the conventional spatial modulation on-chip Fourier spectrometer, a phase modulator is added to each filter unit to modulate the phase of the optical signal passing through the filter unit OF i The light is proportional to the filter unit OF i Optical filter frequency Phase modulation rate Modulation is performed. In this way, the filter unit can modulate the light in the time domain while optically filtering. The modulation result can be expressed mathematically as a phase quantity that presents periodic changes in the time domain:

[0061]

[0062] In formula (1), i represents the i-th filter unit, t represents time, represents the output light intensity of the i-th filter unit, The amplitude I i Proportional to the Fourier transform spectrum of the incident light at frequency The amplitude of the component on The frequency of change in the time domain is also proportional to the frequency of the Fourier transform spectrum of the incident light.

[0063] Furthermore, a non-coherent adder is cascaded after the filter array to add the output phasors of each filter unit. The superposition result can be expressed mathematically as:

[0064]

[0065] In formula (2), t represents time, n represents the total number of filter units, i represents the i-th filter unit, represents the output light intensity of the i-th filter unit, and I(t) represents the output light intensity of the incoherent adder. This incoherent addition process is equivalent to the process of inverse Fourier transform. In this way, the incoherent adder can periodically project the spectral information of the incident light in the spectrum to be measured into the time domain, and the spectral measurement results can be obtained by recording the changes of I(t) in the time domain.

[0066] It can be seen that according to the spectral measurement method based on the spectrometer provided in the embodiment of the present application, the spectral information of the incident light is extracted and analyzed based on the phase modulation of different frequencies of the photonic integrated circuit, and the Fourier spectral components of the spectrum are mapped to the time domain in the form of a light intensity modulation signal, and then the Fourier inverse transform of the spectral information is realized through the superposition process of the incoherent superimposer, so that the measured spectrum is directly constructed in the time domain using the light intensity signal without the need for additional solution programs, thereby reducing the demand for photodetectors, shortening the spectral measurement time, and improving the spectral measurement efficiency.

[0067] As a second aspect of the present application, an electronic device is provided, wherein: Figure 5 As shown, the electronic device includes:

[0068] One or more processors 101;

[0069] The memory 102 stores one or more computer programs. When the one or more computer programs are executed by the one or more processors 101, the one or more processors 101 implement the spectrometer-based spectral measurement method provided in the first aspect of the present application.

[0070] The electronic device may further include one or more I / O interfaces 103 connected between the processor 101 and the memory 102 and configured to implement information interaction between the processor 101 and the memory 102 .

[0071] Among them, the processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU), etc.; the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory (FLASH); the I / O interface (read-write interface) is connected between the processor and the memory, and can realize information exchange between the processor and the memory, including but not limited to a data bus (Bus), etc.

[0072] In some embodiments, the processor 101 , the memory 102 , and the I / O interface 103 are connected to each other via a bus 104 , and further connected to other components of the computing device.

[0073] As a third aspect of the present application, a spectrum measurement system is provided, wherein the spectrum measurement system comprises the electronic device provided according to the third aspect of the present application and a spectrometer, the spectrometer comprises a cascaded optical filter and a measuring device, the optical filter comprises a cascaded beam splitter, a filter array and an incoherent adder, the filter array comprises a plurality of filter units, each of the filter units is provided with a phase modulator;

[0074] The beam splitter is used to divide the incident light into equal parts and input them into each of the filter units; the phase modulator is used to modulate the light passing through the corresponding filter unit according to the phase modulation rate; the incoherent adder is used to incoherently add the output light of each of the filter units; and the measuring device is used to determine the spectral measurement information based on the output light of the incoherent adder.

[0075] The structure and measurement principle of the spectrometer have been described in detail above and will not be repeated here.

[0076] In the embodiment of the present application, there is no specific limitation on the phase adjustment method adopted by the phase modulator. For example, it can be an electrical adjustment method, a thermal adjustment method, etc.

[0077] In the embodiments of the present application, there is no specific limitation on the optical integration platform used to implement the spectrometer. For example, the spectrometer can be implemented on different optical integration platforms such as a silicon-based (Silicon) optical platform (pure silicon or silicon germanium platform), a silicon nitride (Silicon Nitride, SiN) optical platform, an indium phosphide (Indium Phosphide, InP) or indium arsenide (Indium Arsenide, InAs) III-V optical platform, and a lithium phosphate (Lithium Niobate, LN) optical platform.

[0078] In some embodiments, the filter unit is an asymmetric Mach-Zehnder interferometer, and the filter array is composed of a plurality of the asymmetric Mach-Zehnder interferometers connected in parallel, in series, or in a combination of series and parallel.

[0079] In the embodiment of the present application, there is no specific limitation on the number of phase modulators provided on each of the asymmetric Mach-Zehnder interferometers. For example, there may be one or two phase modulators provided on each of the asymmetric Mach-Zehnder interferometers.

[0080] In some embodiments, the measuring device is used to collect light generated after the output light of the incoherent adder passes through a sample object to determine the spectral measurement information.

[0081] The incident light input to the beam splitter may be a broad spectrum light source or a spectrum light source to be measured, which has been described in detail above and will not be repeated here.

[0082] In some embodiments, the phase modulation rate of the filter unit is proportional to its optical filtering frequency.

[0083] In some embodiments, each of the phase modulators provides a periodic phase modulation amount to the light passing through the corresponding filter unit according to each of the phase modulation rates, and the period length of the phase modulation amount is 2π.

[0084] The applicant of this application also constructed a thermally adjustable on-chip filter array and simulated and verified the spectral measurement method based on the spectrometer proposed in this application. 32 asymmetric Mach-Zehnder interferometers are used to form a filter array, and a 1*32 equally divided beam splitter is cascaded in front of the filter array. According to the structural parameters and arm length difference ΔL of the 32 asymmetric Mach-Zehnder interferometers i , the optical filter frequencies of 32 asymmetric Mach-Zehnder interferometers Designed with a ratio of 1:2:3:…:31:32, with the shortest ΔL i Asymmetric Mach-Zehnder interferometer with lowest optical filtering frequency Corresponding to the maximum spectral range to be measured FSR max According to the above design, the phase modulation amount of the phase modulator of 32 asymmetric Mach-Zehnder interferometers is further designed to achieve the above-mentioned phase adjustment rate OF filter unit i Perform phase modulation.

[0085] Considering that the phase modulation range may be limited in practical applications, periodically providing the phase modulation amount in the range of [0-2π] according to the phase modulation rate has the same effect as continuous modulation at a continuous phase modulation rate and is more feasible in engineering.

[0086] Combined with the processing of the incoherent adder and the measuring device, the simulation verification result finally obtained by the applicant of this application, namely the spectral measurement information, has good consistency compared with the actual spectral information, which verifies that the spectral measurement method based on the spectrometer provided in this application has high feasibility.

[0087] As a fourth aspect of the embodiment of the present application, Figure 6As shown, a computer-readable medium is provided, on which a computer program is stored, wherein when the computer program is executed by a processor, the spectrometer-based spectral measurement method provided in the first aspect of the present application is implemented.

[0088] It can be understood by a person of ordinary skill in the art that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program. Accordingly, the computer program can be stored in a non-volatile computer-readable storage medium, and the computer program can implement the method of any of the above-mentioned embodiments when executed. Among them, any reference to memory, storage, database or other media used in the embodiments provided in the embodiments of the present application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0089] The above are only specific embodiments of the present application, but the protection scope of the present application is not limited thereto. Those skilled in the art should understand that the present application includes but is not limited to the contents described in the drawings and the above specific embodiments. Any modification that does not deviate from the functional and structural principles of the present application will be included in the scope of the claims.

Claims

1. A spectrum measurement method based on a spectrometer, characterized in that: The spectrometer comprises a cascaded optical filter and a measuring device, the optical filter comprises a cascaded beam splitter, a filter array and an incoherent adder, the filter array comprises a plurality of filter units, each of the filter units is provided with a phase modulator; the method comprises: Determining the phase modulation rate of each filter unit according to the optical filtering frequency of each filter unit; wherein the phase modulation rate of the filter unit is proportional to its optical filtering frequency; Outputting the determined multiple phase modulation rates to corresponding phase modulators respectively, and inputting the incident light to the beam splitter, so that each phase modulator modulates the light passing through the corresponding filter unit according to each phase modulation rate respectively; Acquire spectral measurement information output by the measuring device; wherein the beam splitter divides the incident light into equal parts and inputs them into each of the filter units, the incoherent adder performs incoherent addition on the output light of each of the filter units, and the measuring device determines the spectral measurement information based on the output light of the incoherent adder.

2. The method according to claim 1, characterized in that The measuring device collects light generated after the output light of the incoherent adder passes through a sample object to determine the spectral measurement information.

3. The method according to claim 1, characterized in that Each of the phase modulators provides a periodic phase modulation amount to the light passing through the corresponding filter unit according to each of the phase modulation rates, and the period length of the phase modulation amount is 2π.

4. An electronic device, characterized in that: The electronic device comprises: one or more processors; A memory having one or more computer programs stored thereon, wherein when the one or more computer programs are executed by the one or more processors, the one or more processors implement the spectrometer-based spectral measurement method according to any one of claims 1-3.

5. A spectrum measurement system, characterized in that: The spectrum measurement system comprises the electronic device according to claim 4 and a spectrometer, the spectrometer comprises a cascaded optical filter and a measuring device, the optical filter comprises a cascaded beam splitter, a filter array and an incoherent adder, the filter array comprises a plurality of filter units, each of the filter units is provided with a phase modulator; The beam splitter is used to divide the incident light into equal parts and input them into each of the filter units; the phase modulator is used to modulate the light passing through the corresponding filter unit according to the phase modulation rate; the incoherent adder is used to incoherently add the output light of each of the filter units; and the measuring device is used to determine the spectral measurement information based on the output light of the incoherent adder; wherein the phase modulation rate of the filter unit is proportional to its optical filtering frequency.

6. The spectrum measurement system according to claim 5, characterized in that: The filter unit is an asymmetric Mach-Zehnder interferometer, and the filter array is composed of a plurality of the asymmetric Mach-Zehnder interferometers connected in parallel or in series or in a combination of series and parallel.

7. The spectrum measurement system according to claim 5 or 6, characterized in that: The measuring device is used to collect the light generated after the output light of the incoherent adder passes through the sample object, so as to determine the spectrum measurement information.

8. A computer readable medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the spectrometer-based spectrum measurement method according to any one of claims 1 to 3 is implemented.

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