An interferogram distortion detection method and system

Abstract

The application discloses an interferogram distortion detection method and system, which comprises the following steps: detecting the main peak value of a target interferogram; judging whether the interferogram is an effective interferogram containing effective target information based on the detected main peak value; if the interferogram is an effective interferogram containing effective target information, positioning the main peak and each order peak of the interferogram by using a local maximum value method; and identifying and judging whether the target interferogram has distortion based on the positioned main peak and each order peak of the interferogram, so that simple, efficient and high-precision identification and detection of distorted interferograms of a Fourier transform infrared spectral radiometer are realized.

Description

Technical Field

[0001] This invention relates to the field of Fourier transform infrared spectroscopy radiometric measurement technology, and in particular to an interferogram distortion detection method and system. Background Technology

[0002] Fourier transform spectral radiometric measurement technology possesses advantages such as high spectral resolution, high optical flux, multi-channel operation, and wide spectral coverage, making it a crucial high-resolution spectral analysis technique. In particular, wide-band infrared spectral radiometric measurement is currently widely applied in various fields including space remote sensing, target characteristic research, atmospheric detection, material analysis, security and chemical defense, metrology, laboratories, environment, medicine, military analysis, and criminal investigation. With the rapid development of infrared stealth technology and hypersonic technology, there is an urgent need for highly sensitive, real-time infrared spectral radiometric parameter measurements of low-emissivity, fast-flying targets.

[0003] Unlike traditional infrared spectral radiometry systems based on prisms, gratings, or filters, Fourier transform spectral radiometry acquires the interferometric data of a target. Only after performing a series of data processing steps, such as Fourier transform, on this interferometric data can the target's infrared spectral data be obtained. Due to defects in the interferometer's optical system, electronic noise abnormalities, and jitter during mirror movement, the interferometric data acquired by Fourier transform spectral instruments may contain distorted interferograms. Subsequent processing, such as Fourier transform, on these distorted interferograms may yield incorrect target spectral information, leading to erroneous measurement results. Currently, manual screening is often used to address this issue, but this method is inefficient and inaccurate. Summary of the Invention

[0004] To address the shortcomings of the existing technologies, this invention provides an interferogram distortion detection method and system. This system enables low-complexity, high-efficiency, and high-precision automatic identification of interferogram distortions obtained from Fourier transform spectroradiometers, thus laying a solid foundation for subsequent processing and removal of distorted interferograms.

[0005] Firstly, this disclosure provides a method for detecting interferogram distortion.

[0006] An interferogram distortion detection method, comprising:

[0007] Obtain the target interferogram and perform main peak detection on the interferogram.

[0008] Based on the detected main peak value of the interferogram, it is determined whether the interferogram is a valid interferogram containing effective target information;

[0009] If the interferogram is a valid interferogram containing effective target information, the local maximum method is used to locate the main peak and all levels of secondary peaks in the interferogram.

[0010] Based on the main peak and each order peak of the interference figure, it is identified and judged whether the target interference figure has distortion.

[0011] Further technical solutions, the interference figure main peak value detection includes:

[0012] The target interference figure is input into the hardware detection circuit of the Fourier transform spectrometer, and the approximate position of the zero optical path difference point is output by the hardware detection circuit;

[0013] Taking the approximate position as a center point, a certain number of symmetric points are taken left and right to obtain a segment of data, the maximum value point in the segment of data is searched, and the maximum value point is taken as the main peak value of the interference figure.

[0014] Further technical solutions, based on the detected main peak value of the interference figure, it is judged whether the interference figure is an effective interference figure containing effective target information, including:

[0015] The detected main peak value of the interference figure is compared with the noise limit of the Fourier transform spectrometer radiometer, if the main peak value of the interference figure is less than the noise limit of the Fourier transform spectrometer radiometer, it is judged that the interference figure is an ineffective interference figure not containing effective target information, otherwise it is judged that the interference figure is an effective interference figure containing effective target information.

[0016] Further technical solutions, the local maximum value method is used to locate the main peak and each order peak of the interference figure, including:

[0017] A segment of data with a set data length is selected by using a sliding window, the maximum value point of the segment of data is determined, and if the number of points left and right of the maximum value point exceeds the set number, it is judged that the maximum point is the peak point of the interference figure.

[0018] Further technical solutions, based on the located main peak and each order peak of the interference figure, it is identified and judged whether the target interference figure has distortion, including:

[0019] If each order peak is symmetrically distributed with the main peak and the peak value gradually decreases, it is determined that the target interference figure is a normal interference figure and does not have interference figure distortion;

[0020] If each order peak is symmetrically distributed with the main peak but the peak value does not gradually decrease, the amplitude value difference of adjacent spectral peaks is calculated, and if the difference value is greater than a threshold value, it is determined that the target interference figure has distortion.

[0021] Secondly, the present disclosure provides an interference figure distortion detection system, including:

[0022] A target interference figure acquisition module is configured to acquire a target interference figure.

[0023] The target interferogram processing module is configured to perform interferogram main peak detection on the target interferogram, determine whether the interferogram is an effective interferogram containing effective target information based on the detected interferogram main peak, and locate the main peak and each order peak of the interferogram by using a local maximum value method if the interferogram is an effective interferogram containing effective target information.

[0024] The target interferogram distortion detection module is configured to identify and determine whether the target interferogram has distortion based on the located main peak and each order peak of the interferogram.

[0025] In a further technical solution, the determination of whether the interferogram is an effective interferogram containing effective target information based on the detected interferogram main peak includes:

[0026] The detected interferogram main peak value is compared with a noise limit of the Fourier transform infrared spectroradiometer, and if the interferogram main peak value is less than the noise limit of the Fourier transform infrared spectroradiometer, it is determined that the interferogram is an ineffective interferogram not containing effective target information, and otherwise, it is determined that the interferogram is an effective interferogram containing effective target information.

[0027] In a further technical solution, the identification and determination of whether the target interferogram has distortion based on the located main peak and each order peak of the interferogram include:

[0028] If the order peaks are symmetrically distributed with respect to the main peak and the peak values gradually decrease, it is determined that the target interferogram is a normal interferogram and does not have interferogram distortion.

[0029] If the order peaks are symmetrically distributed with respect to the main peak but the peak values do not gradually decrease, the amplitude value difference of adjacent spectral peaks is calculated, and if the difference is greater than a threshold value, it is determined that the target interferogram has distortion.

[0030] In a third aspect, the disclosure also provides an electronic device including a memory and a processor, and computer instructions stored in the memory and running on the processor, and when the computer instructions are run by the processor, the steps of the method of the first aspect are completed.

[0031] In a fourth aspect, the disclosure also provides a computer-readable storage medium for storing computer instructions, and when the computer instructions are executed by a processor, the steps of the method of the first aspect are completed.

[0032] The above one or more technical solutions have the following beneficial effects:

[0033] 1. The present application provides an interferogram distortion detection method and system, which does not need to update the hardware, only needs to add an interferogram distortion detection and identification process in the data processing link, and can conveniently realize automatic identification, that is, realizes identification and detection of distorted interferograms of the Fourier transform infrared spectroradiometer, and has the characteristics of simplicity, efficiency and high precision.

[0034] 2、The present application can be conveniently applied to the existing Fourier transform principle wide-band infrared spectrum radiometer, and realizes efficient detection and identification of the interference figure distortion. BRIEF DESCRIPTION OF DRAWINGS

[0035] The accompanying drawings, which form a part of this specification, are included to provide a further understanding of the application and are incorporated in and constitute a part of this specification. The embodiments of the application, and their

[0036] Figure 1 The flow chart of the interference figure distortion detection method in the first embodiment of the present application;

[0037] Figure 2 The interference figure with distortion obtained by the Fourier transform infrared spectrum radiometer;

[0038] Figure 3 The target interference figure with distortion measured by the Fourier transform spectrum radiometer and the spectrum diagram based on the target interference figure inversion. DETAILED DESCRIPTION

[0039] It should be noted that the following detailed description is merely exemplary in nature and is intended to provide further description of the application. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

[0040] It is to be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, elements, components, and / or groups thereof, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0041] Embodiment one

[0042] In view of the low recognition efficiency and poor recognition accuracy of the artificial recognition of the distorted interference figure as pointed out in the background art, the present embodiment provides an interference figure distortion detection method, as shown in Figure 1 The method comprises the following steps:

[0043] Step S1, obtaining a target interference figure, and performing interference figure main peak detection on the target interference figure;

[0044] Step S2, judging whether the interference figure is an effective interference figure containing effective target information based on the detected interference figure main peak;

[0045] Step S3: If the interferogram is a valid interferogram containing effective target information, the local maximum method is used to locate the main peak and all levels of secondary peaks in the interferogram;

[0046] Step S4: Based on the main peak and all levels of secondary peaks of the interferogram, identify and determine whether there is distortion in the target interferogram.

[0047] Existing Fourier transform radiometers, when measuring the spectral radiometry of a target, first acquire the target's interferometric data, then perform a Fourier transform on the interferometric data to obtain the target's infrared spectral data. In this process, due to defects in the interferometer and other optical systems, abnormal electronic noise, and jitter during mirror movement, the interferometric data acquired by the Fourier transform radiometer may contain distorted interferograms. If such distorted interferograms are subsequently processed through Fourier transforms or other methods, incorrect target spectral information may be obtained, leading to erroneous measurement results. Figure 2 As shown, the Fourier transform infrared spectroradiometer acquires an interferogram with distortion, but the infrared spectral data obtained through Fourier transform is as follows: Figure 3 As shown, the spectral data measurement is incorrect. In existing technologies, distorted interferograms are typically identified using the aforementioned manual identification methods. However, in reality, distorted interferograms are not so obvious or easy to confirm. Therefore, existing manual identification methods cannot guarantee accuracy and are inefficient and time-consuming.

[0048] Therefore, this embodiment provides an interferogram distortion detection method. First, in step S1, a target interferogram is acquired using a Fourier transform spectroradiometer, and the main peak of the interferogram is detected. The main peak detection is divided into two steps. In the first step, the target interferogram is input into the hardware detection circuit of the Fourier transform spectroradiometer, and the hardware detection circuit outputs the approximate location of the zero optical path difference (NZPD) point. In the second step, with the approximate location as the center point, symmetrical points are taken to the left and right to obtain a data segment. The maximum value point is searched in the data segment and taken as the main peak of the interferogram.

[0049] After determining the dominant peak value of the target interferogram, step S2 is executed. Based on the detected dominant peak value, it is determined whether the interferogram is a valid interferogram containing effective target information. Specifically, the detected dominant peak value of the interferogram is compared with the noise limit of the Fourier transform radiometer. If the dominant peak value of the interferogram is less than the noise limit of the Fourier transform radiometer, the interferogram is determined to be an invalid interferogram that does not contain effective target information, i.e., it is noise data that does not contain effective target signals. In this case, no further detection is performed. Otherwise, the interferogram is determined to be a valid interferogram containing effective target information.

[0050] For long-wave interferograms with refrigerated MCT detectors, the noise limit is usually set to 200; for mid-wave interferograms with refrigerated InSb detectors, the noise limit is usually set to 300. Further, the parameters can be adjusted according to the electronics of the infrared spectral radiometer used.

[0051] In step S3, if the interferogram is an effective interferogram containing effective target information, the main peak and each order peak of the interferogram are located by using a local maximum method.

[0052] Specifically, the local maximum method is used for interferogram peak positioning, including: a sliding window is used to select a data segment of a set data length of the interferogram, the maximum point of the data segment is determined, and if the number of points to the left and right of the maximum point exceeds a set number, the maximum point is determined as a peak point of the interferogram. According to the characteristics of the interferogram, the length of the data segment selected by the sliding window is usually 200 points, and the set number of points to the left and right of the peak point is usually 40. Further, the data segment length and the set number can be adjusted according to the detection effect.

[0053] In step S4, based on the located main peak and each order peak of the interferogram, it is identified and determined whether the target interferogram has distortion. Specifically, according to the located main peak and each order peak of the interferogram, if each order peak is symmetrically distributed with the main peak and the peak value gradually decreases, it is determined that the target interferogram is a normal interferogram and does not have interferogram distortion; if each order peak is symmetrically distributed with the main peak but the peak value does not gradually decrease, the amplitude value difference of adjacent spectral peaks is calculated, and if the difference is greater than a threshold value, it is determined that the target interferogram has distortion; if the difference is less than the threshold value, it is determined that the target interferogram is an interferogram with noise interference. At this time, when the Fourier transform infrared spectral radiometer is applied to target precise composition and other precise quantitative analysis occasions, it is necessary to apply wavelet filtering, smoothing, multi-interferogram superposition, principal component analysis and other filtering algorithms to the interferogram with noise interference to improve the measurement accuracy; when it is applied to target identification and other qualitative analysis, it is not necessary to perform subsequent processing. That is, at this time, it is determined whether to perform subsequent processing according to the application occasion of the Fourier transform infrared spectral radiometer.

[0054] Further, according to the characteristics of the interferogram, the above-mentioned threshold value is usually selected as one-twentieth of the main peak value of the interferogram, and can also be adjusted according to the detection effect.

[0055] By using the above-mentioned interferogram distortion detection method of the embodiment, without updating the hardware, only by adding the interferogram distortion detection and identification process in the data processing link, automatic identification can be easily realized, that is, the identification and detection of the distorted interferogram of the Fourier transform infrared spectral radiometer can be realized, and the method has the characteristics of simplicity, efficiency and high precision.

[0056] Embodiment Two

[0057] The embodiment provides an interferogram distortion detection system, comprising:

[0058] An object interferogram acquisition module is configured to acquire an object interferogram.

[0059] An object interferogram processing module is configured to perform interferogram main peak detection on the object interferogram, to determine whether the interferogram is an effective interferogram containing effective target information based on the detected interferogram main peak, and to locate the main peak and each order peak of the interferogram by using a local maximum value method if the interferogram is the effective interferogram containing effective target information.

[0060] An object interferogram distortion detection module is configured to identify and determine whether the object interferogram has distortion based on the located main peak and each order peak of the interferogram.

[0061] Embodiment three

[0062] A wide-band infrared spectrum radiometer adopts the interferogram distortion detection method provided in the embodiment one, and realizes identification and detection of distorted interferograms of the Fourier transform infrared spectrum radiometer.

[0063] Embodiment four

[0064] The embodiment provides an electronic device, which comprises a memory, a processor, computer instructions stored in the memory and running on the processor, and when the computer instructions are run by the processor, the steps in the interferogram distortion detection method are completed.

[0065] Embodiment five

[0066] The embodiment also provides a computer readable storage medium for storing computer instructions, and when the computer instructions are executed by the processor, the steps in the interferogram distortion detection method are completed.

[0067] The steps and method of the above embodiments two to five correspond to the embodiment one, and the specific embodiments can refer to the related description part of the embodiment one. The term "computer readable storage medium" should be understood as including a single medium or multiple media of one or more instruction sets; and should also be understood as including any medium capable of storing, encoding or carrying instruction sets for execution by a processor and causing the processor to perform any method in the present application.

[0068] Those skilled in the art will understand that the modules or steps of the present invention described above can be implemented using general-purpose computer devices. Optionally, they can be implemented using computer-executable program code, thereby allowing them to be stored in a storage device for execution by a computer device, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. The present invention is not limited to any particular combination of hardware and software.

[0069] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

[0070] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A method for detecting interferogram distortion, characterized in that, include: Obtain the target interferogram and perform main peak detection on the interferogram. Based on the detected main peak value of the interferogram, it is determined whether the interferogram is a valid interferogram containing effective target information; If the interferogram is a valid interferogram containing effective target information, the local maximum method is used to locate the main peak and all levels of secondary peaks in the interferogram. Based on the location of the main peak and all levels of secondary peaks in the interferogram, identify and determine whether there is distortion in the target interferogram; The main peak detection of the interferogram includes: The target interferogram is input into the hardware detection circuit of the Fourier transform spectrometer, and the hardware detection circuit outputs the approximate location of the zero optical path difference point. Using the approximate location as the center point, take symmetrical points to the left and right to obtain a data segment. Search for the maximum value point in this data segment and take the maximum value point as the main peak of the interferogram.

2. The interferogram distortion detection method as described in claim 1, characterized in that, Based on the detected main peak value of the interferogram, it is determined whether the interferogram is a valid interferogram containing effective target information, including: The main peak value of the detected interferogram is compared with the noise limit of the Fourier transform spectroradiometer. If the main peak value of the interferogram is less than the noise limit of the Fourier transform spectroradiometer, the interferogram is judged to be an ineffective interferogram that does not contain effective target information; otherwise, the interferogram is judged to be an effective interferogram that contains effective target information.

3. The interferogram distortion detection method as described in claim 1, characterized in that, The local maximum method was used to locate the main peak and all secondary peaks of the interferogram, including: A segment of data of a set length in the interferogram is selected using a sliding window. The maximum value point of this segment is determined. If the number of points to the left and right of the maximum value point exceeds the set number, then the maximum value point is determined to be the peak point of the interferogram.

4. The interferogram distortion detection method as described in claim 1, characterized in that, Based on the location of the main peak and all secondary peaks of the interferogram, identify and determine whether there is distortion in the target interferogram, including: If the secondary peaks are symmetrically distributed with the main peak and the peak values ​​gradually decrease, then the target interferogram is determined to be a normal interferogram and there is no interferogram distortion. If each level of secondary peaks is symmetrically distributed with the main peak but the peak value does not gradually decrease, then the amplitude difference between adjacent spectral peaks is calculated. If the difference is greater than the threshold, then the target interferogram is determined to be distorted.

5. An interferogram distortion detection system, characterized in that, include: The target interferogram acquisition module is used to acquire the target interferogram. The target interferogram processing module is used to detect the main peak of the interferogram. Based on the detected main peak, it determines whether the interferogram is a valid interferogram containing effective target information. If the interferogram is a valid interferogram containing effective target information, the local maximum method is used to locate the main peak and all levels of secondary peaks of the interferogram. The target interferogram distortion detection module is used to identify and determine whether there is distortion in the target interferogram based on the main peak and all levels of secondary peaks of the interferogram. The main peak detection of the interferogram includes: The target interferogram is input into the hardware detection circuit of the Fourier transform spectrometer, and the hardware detection circuit outputs the approximate location of the zero optical path difference point. Using the approximate location as the center point, take symmetrical points to the left and right to obtain a data segment. Search for the maximum value point in this data segment and take the maximum value point as the main peak of the interferogram.

6. The interferogram distortion detection system as described in claim 5, characterized in that, Based on the location of the main peak and all secondary peaks of the interferogram, identify and determine whether there is distortion in the target interferogram, including: If the secondary peaks are symmetrically distributed with the main peak and the peak values ​​gradually decrease, then the target interferogram is determined to be a normal interferogram and there is no interferogram distortion. If each level of secondary peaks is symmetrically distributed with the main peak but the peak value does not gradually decrease, then the amplitude difference between adjacent spectral peaks is calculated. If the difference is greater than the threshold, then the target interferogram is determined to be distorted.

7. An electronic device, characterized in that: It includes a memory and a processor, as well as computer instructions stored in the memory and running on the processor, which, when executed by the processor, complete the steps of an interferogram distortion detection method as described in any one of claims 1-4.

8. A computer-readable storage medium, characterized in that: Used to store computer instructions, which, when executed by a processor, complete the steps of an interferogram distortion detection method as described in any one of claims 1-4.

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