Multi-angle different-plane detection device and method based on three-wavelength laser double detectors

Abstract

The invention relates to the technical field of environmental monitoring, and discloses a multi-angle different-plane detection device and method based on three-wavelength laser double detectors, and the device comprises a three-wavelength laser emission unit which is configured to synchronously emit laser beams with at least three different wavelengths; the electric detector different-plane receiving unit is configured to acquire particulate matter scattered light signals at multiple angles; and a stray light suppression housing unit configured to suppress non-target optical path interference. According to the multi-angle different-plane detection device and method based on the three-wavelength laser double detectors, wide particle size coverage and optimal excitation efficiency are provided through three wavelengths; multi-angle different-plane detection maximizes scattered light information acquisition and reduces interference; the stray light suppression shell guarantees high purity of signals, and high-precision and high-stability particulate matter on-line monitoring is achieved by combining the stray light suppression shell, the stray light suppression shell and the stray light suppression shell.

Description

Technical Field

[0001] The present invention relates to the technical field of environmental monitoring, and in particular to a multi-angle out-of-plane detection device and method based on three-wavelength laser dual detectors. Background Art

[0002] With the acceleration of industrialization and the continued growth of energy consumption, air pollution has become increasingly serious. Particulate matter pollution has become a prominent problem affecting environmental quality and human health. Airborne particulate matter, including tiny dust, smoke particles, pollen, and microorganisms, ranges in diameter from a few nanometers to tens of microns. Fine particulate matter, in particular, can penetrate deep into the human respiratory tract and even enter the bloodstream, causing respiratory and cardiovascular diseases and other health issues. Furthermore, particulate matter has profound impacts on visibility and climate change, such as reducing atmospheric transparency, disrupting normal transportation, and altering atmospheric heating processes by absorbing and scattering solar radiation, affecting the global climate system.

[0003] Traditional particulate matter monitoring methods, such as weight method and optical microscopy method, have limitations such as complex operation, long detection time, and inability to monitor in real time. They are unable to meet the modern society's demand for precise and real-time air quality and environmental monitoring.

[0004] Against this backdrop, particulate matter sensors have emerged. Using a variety of principles, including electrical, optical, and acoustic, these sensors can quickly and sensitively detect the concentration and distribution of particulate matter in the air. They provide real-time data support for environmental monitoring, aiding the dynamic monitoring and assessment of air quality. They also provide a key basis for the precise implementation of air pollution prevention and control measures. They also play a vital role in indoor environmental quality monitoring and industrial dust emission control.

[0005] In particular, existing sensors generally have the following key factors that restrict accuracy: a single wavelength or limited wavelength makes it difficult to cover a wide particle size range and achieve optimal sensitivity; the detector layout is single, resulting in insufficient collection of scattered light information and susceptibility to noise interference. Summary of the Invention

[0006] In view of the shortcomings of the existing technology, the present invention proposes a multi-angle out-of-plane detection device and method based on three-wavelength laser dual detectors to solve the above technical problems.

[0007] In the first aspect, a multi-angle out-of-plane detection device based on a three-wavelength laser dual detector is provided, comprising: a three-wavelength laser emitting unit configured to synchronously emit laser beams of at least three different wavelengths; The electric detector's out-of-plane receiving unit is configured to collect particle scattered light signals at multiple angles; A stray light suppression housing unit is configured to suppress non-target light path interference.

[0008] Furthermore, the three-wave laser emission unit includes: a first laser configured to optimize scattering efficiency for submicron particles; a second laser configured to optimize scattering efficiency for micron-sized particles; A third laser is configured to penetrate high humidity environments and supplement large particle detection.

[0009] Furthermore, the electrical detector out-of-plane receiving unit includes: A plurality of first photodetectors and a plurality of second photodetectors, wherein the first photodetectors and the second photodetectors are respectively fixed at different spatial positions on opposite sides of the monitoring device; The out-of-plane spatial position is configured to capture scattered light generated after multi-angle asymmetric laser irradiation.

[0010] Furthermore, the stray light suppression housing unit includes: Interior coating; An optical path channel, including an air inlet, an air outlet and multiple laser incident ports; An internal light blocking structure is configured to block non-target light paths.

[0011] Furthermore, the inner wall coating is made of carbon nanotube composite light-absorbing material.

[0012] Furthermore, it also includes: The signal processing unit is configured to calculate the particle size distribution and concentration based on the difference in the intensity of the scattered light at multiple angles collected by the out-of-plane detector.

[0013] Furthermore, the signal processing unit includes: a noise compensation module configured to separate water vapor scattering noise based on the laser channel signal; The multi-dimensional fusion algorithm module is configured to correlate the three-wavelength scattered light intensity with the spatial angle difference of the two detectors to invert the particle size distribution.

[0014] In a second aspect, a method for multi-angle out-of-plane detection based on a three-wavelength laser dual detector is provided, and a multi-angle out-of-plane detection device based on a three-wavelength laser dual detector is provided based on any of the above items, including: The three-wavelength laser beam is used to asymmetrically illuminate the particle group to be measured from multiple angles; Synchronously collecting multi-dimensional scattered light signals using a first photodetector and a second photodetector arranged in different spatial planes; Filtering background noise through stray light suppression housing units; Correlation analysis of particle size and concentration based on multi-angle scattered light intensity.

[0015] Furthermore, the three-wavelength laser beam includes: a first short-wavelength beam sensitive to submicron particles; a second medium-wavelength beam sensitive to micronized particles; A third-longest wavelength beam with high ambient penetration.

[0016] Furthermore, the multi-dimensional scattered light signal acquisition includes: Synchronously acquiring scattered light signals collected by the first photodetector and the second photodetector at different spatial positions; Based on the spatial isolation characteristics of the out-of-plane layout, the optical crosstalk noise between detectors is separated and eliminated.

[0017] The invention adopting the above technical solution has the following advantages: This invention utilizes three wavelengths to provide wide particle size coverage and optimal excitation efficiency; multi-angle, out-of-plane detection maximizes scattered light information collection and reduces interference; and a stray light suppression housing ensures high signal purity. These three features combine to achieve high-precision, high-stability online particulate matter monitoring. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific embodiments of the present invention, the following briefly introduces the drawings required for use in the specific embodiments. In all the drawings, each element or part is not necessarily drawn according to the actual scale.

[0019] Figure 1 This is a schematic structural diagram of a multi-angle out-of-plane detection device based on three-wavelength lasers and dual detectors according to the present invention; Figure 2 This is a flow chart of the multi-angle out-of-plane detection device based on three-wavelength laser and dual detectors of the present invention; Figure 3 This is a flow chart of the multi-angle out-of-plane detection method based on three-wavelength laser dual detectors of the present invention.

[0020] Reference numerals: A first photodetector 1; a laser emitter 2; a laser incident port 3; an air inlet 4; an air outlet 5; a second photodetector 6; and a stray light suppression unit 7. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0022] The terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0023] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0024] like Figures 1 to 3 As shown, the present invention is based on a three-wavelength laser dual-detector multi-angle out-of-plane detection device, comprising: a three-wavelength laser emitting unit configured to synchronously emit laser beams of at least three different wavelengths; The electric detector's out-of-plane receiving unit is configured to collect particle scattered light signals at multiple angles; The stray light suppression housing unit 7 is configured to suppress non-target light path interference.

[0025] Specifically, three wavelengths provide wide particle size coverage and optimal excitation efficiency; multi-angle, out-of-plane detection maximizes scattered light information collection and reduces interference; and the stray light suppression housing unit 7 ensures high signal purity. These three features combine to achieve high-precision and high-stability online particulate matter monitoring.

[0026] In this embodiment, the three-wave laser emitting unit includes: a first laser configured to optimize scattering efficiency for submicron particles; a second laser configured to optimize scattering efficiency for micron-sized particles; A third laser is configured to penetrate high humidity environments and supplement large particle detection.

[0027] Specifically, it consists of laser emitters 2 with wavelengths of 405nm, 635nm, and 980nm, respectively. The wavelengths were selected based on optimizing the scattering efficiency of particles of varying sizes. The 405nm laser has a good scattering response for submicron particles and smaller (such as PM2.5 and PM10). The 980nm laser effectively penetrates water vapor interference in high-humidity environments and provides supplementary information on larger particles. These three wavelengths work together to achieve full coverage and optimal detection sensitivity for particles ranging from 0.1μm to 10μm.

[0028] In this embodiment, the electrical detector out-of-plane receiving unit includes: A plurality of first photodetectors 1 and a plurality of second photodetectors 6, wherein the first photodetectors 1 and the second photodetectors 6 are respectively fixed at different spatial positions on opposite sides of the monitoring device; The out-of-plane spatial position is configured to capture scattered light generated after multi-angle asymmetric laser irradiation.

[0029] Specifically, multiple first photodetectors 1 and multiple second photodetectors 6 are installed non-coplanarly, and are located on the left and right sides of the monitoring device, respectively, to form a multi-angle non-planar detection array. The core lies in: Multi-angle design: The laser emitter 2 is not incident in parallel, and its installation angle has been precisely optimized: The 405nm laser transmitter 2 is installed on the upper right side of the housing, rotated 165° counterclockwise; The 635nm laser transmitter 2 is installed on the upper right side of the housing, rotated 15° counterclockwise; The 980nm laser transmitter 2 is installed at a position rotated 155° clockwise at the lower right end of the housing.

[0030] This asymmetric, multi-angle incident design allows the scattered light generated by particles of different sizes to be more effectively captured by detectors at different spatial positions.

[0031] The core purpose of the multi-angle design is to optimize the incident angle layout of the laser emitter 2. By planning the incident angles of laser beams of different wavelengths, the spatial irradiation range of the laser beam in the detection area is expanded, thereby fully covering particles of different particle sizes and different motion trajectories in the detection area, ensuring that particles of all particle sizes are within the effective laser irradiation range, and providing a full-dimensional and three-dimensional sampling perspective for subsequent scattered light signal acquisition, thereby improving sampling efficiency and information integrity, ensuring that the scattered light signals of particles of different particle sizes can be effectively captured, and realizing accurate detection and comprehensive characterization of particles.

[0032] Out-of-plane layout: Two sets of photodetectors are located on the left and right sides of the monitoring device, forming an out-of-plane layout. This layout significantly expands the solid angle of effective scattered light signal acquisition, greatly increasing the amount of scattered light information that can be obtained, while effectively reducing signal crosstalk and background noise interference that may be caused by the coplanarity of the detectors.

[0033] In this embodiment, the stray light suppression housing unit 7 includes: Interior coating; The optical path includes an air inlet 4, an air outlet 5 and multiple laser incident ports 3; An internal light blocking structure is configured to block non-target light paths.

[0034] In this embodiment, the inner wall coating is made of carbon nanotube composite light-absorbing material.

[0035] Specifically, the stray light suppression housing 7 unit consists of a specially designed stray light suppression housing 7. The surface of the housing's internal cavity is treated with a special coating with high absorptivity and low reflectivity. It is also designed with a precise optical path (air inlet 4, air outlet 5, laser incident port 3) and an internal light-blocking structure. An air pump is installed inside the air inlet 4.

[0036] The core functions are: Minimize the amount of stray light such as reflection and refraction of the laser beam on the inner wall of the shell, optical windows, and other surfaces other than particulate matter.

[0037] Ensure that only the effective forward / side scattered light generated by the target particles can reach the photodetector efficiently and with low noise.

[0038] Significantly improve the signal-to-noise ratio of the system, especially in environments with background light interference or high concentrations of particulate matter, to ensure measurement stability and accuracy.

[0039] In this embodiment, it also includes: The signal processing unit is configured to calculate the particle size distribution and concentration based on the difference in the intensity of the scattered light at multiple angles collected by the out-of-plane detector.

[0040] In this embodiment, the signal processing unit includes: a noise compensation module configured to separate water vapor scattering noise based on the laser channel signal; The multi-dimensional fusion algorithm module is configured to correlate the three-wavelength scattered light intensity with the spatial angle difference of the two detectors to invert the particle size distribution.

[0041] Specifically, the environmental penetration characteristics of the 980nm laser channel are used to construct a reference signal: Real-time monitoring of the scattered light intensity fluctuations of the 980nm channel was used to establish a nonlinear mapping model between water vapor concentration and noise intensity; Dynamically subtract water vapor interference from 405nm / 635nm signals through adaptive filtering algorithms; Specially set up humidity compensation system (RH is relative humidity). When RH>80%, the enhanced compensation mode is activated.

[0042] Modeling spatial angle differences: Define the detector out-of-plane gain factor ( The first detector spatial orientation angle, The second detector spatial orientation angle is used to correct the anisotropy of scattered light intensity.

[0043] Core process of particle size inversion: Establish a Mie scattering theory database: pre-store the scattering intensity distribution of 0.1-10μm particles at three wavelengths; Construct feature vectors from dual-detector multi-angle signals: in, The signal difference between the two detectors For signal and.

[0044] The particle swarm optimization algorithm is used to match the optimal solution of the database and output the particle size distribution histogram.

[0045] In other embodiments, a method for detecting a misalignment of surfaces at multiple angles based on a three-wavelength laser and dual detectors is provided. The device for detecting a misalignment of surfaces at multiple angles based on a three-wavelength laser and dual detectors is provided according to any one of the above items, including: Step S01: A three-wavelength laser beam is used to asymmetrically illuminate a group of particles to be measured from multiple angles; Step S02: synchronously collecting multi-dimensional scattered light signals using the first photodetector 1 and the second photodetector 6 arranged in different spatial planes; Step S03: filtering background noise through the stray light suppression housing 7 unit; Step S04: analyzing the particle size and concentration based on the correlation of the multi-angle scattered light intensity.

[0046] In this embodiment, the three-wavelength laser beam includes: a first short-wavelength beam sensitive to submicron particles; a second medium-wavelength beam sensitive to micronized particles; A third-longest wavelength beam with high ambient penetration.

[0047] In this embodiment, multi-dimensional scattered light signal acquisition includes: Synchronously acquiring scattered light signals collected by the first photodetector 1 and the second photodetector 6 at different spatial positions; Based on the spatial isolation characteristics of the out-of-plane layout, the optical crosstalk noise between detectors is separated and eliminated.

[0048] Specifically, when the device is working, the air inlet 4 inhales particulate matter in the air through the air pump, and three lasers with different wavelengths simultaneously emit laser beams. When the particles to be measured in the shell cavity are irradiated by the laser beam, scattered light is generated. The scattered light is received by the first photodetector 1 and the second photodetector 6. By analyzing the scattered light signals of different intensities, the photodetector converts the scattered light signals into electrical signals by processing them, and the electrical signals are processed to obtain the particle diameter and concentration.

[0049] This invention aims to address the shortcomings of existing particulate matter sensors in terms of detection accuracy, stability, response speed, and adaptability to complex environments. Specifically, traditional particulate matter sensors are prone to reduced detection accuracy and signal drift in complex environmental conditions such as high humidity and high pollution. Some sensors also have low sensitivity for fine particulate matter, making them incapable of accurately monitoring low-concentration particulate matter. Furthermore, some existing sensors have long response times, making them unable to reflect rapid changes in particulate matter concentration in real time.

[0050] To solve the above problems, a three-wavelength laser collaborative design of 405nm, 635nm and 980nm is adopted to optimize the scattering characteristics of particles of different sizes in a wide particle size range of 0.1μm to 10μm, significantly improving the detection sensitivity and accuracy of submicron fine particles and ultrafine particles, and solving the problem of insufficient coverage of a single wavelength.

[0051] Multi-angle laser incidence combined with inhomogeneous spatially distributed detectors significantly expands the effective scattered light collection solid angle and information dimension (multi-angle scattered light intensity), providing a richer data basis for particle size analysis; At the same time, the out-of-plane design effectively isolates optical crosstalk between detectors and reduces common-mode noise. The stray light suppression housing 7 design effectively provides a high stray light suppression rate, achieving measurement stability and accuracy under harsh conditions such as complex ambient light interference, overcoming the problem that traditional sensors are easily affected by the environment.

[0052] It should be noted that for the aforementioned method embodiments, for the sake of simplicity, they are all expressed as a series of action combinations, but those skilled in the art should be aware that this application is not limited by the order of the actions described, because according to this application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required by this application.

[0053] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0054] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0055] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0056] In addition, the functional units in the various embodiments of the application may be integrated into a single processing unit, or each unit may exist physically separately, or two or more units may be integrated into a single unit. The aforementioned integrated units may be implemented in the form of hardware or software program modules.

[0057] If the integrated unit is implemented in the form of a software program module and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a memory and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned memory includes: U disk, read-only memory (ROM), random access memory (RAM), mobile hard disk, magnetic disk, or optical disk, etc., various media that can store program code.

[0058] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be completed by instructing related hardware through a program, and the program can be stored in a computer-readable memory, which may include: a flash drive, a read-only memory, a random access memory, a magnetic disk or an optical disk, etc.

[0059] The above is a detailed introduction to the embodiments of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those skilled in the art, according to the idea of ​​the present application, there may be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. Based on the three-wavelength laser dual-detector multi-angle out-of-plane detection device, it is characterized by: include: a three-wavelength laser emitting unit configured to synchronously emit laser beams of at least three different wavelengths; The electric detector's out-of-plane receiving unit is configured to collect particle scattered light signals at multiple angles; A stray light suppression housing unit is configured to suppress non-target light path interference.

2. The multi-angle out-of-plane detection device based on three-wavelength laser and dual detectors according to claim 1 is characterized in that: The three-wave laser emitting unit includes: a first laser configured to optimize scattering efficiency for submicron particles; a second laser configured to optimize scattering efficiency for micron-sized particles; A third laser is configured to penetrate high humidity environments and supplement large particle detection.

3. The multi-angle out-of-plane detection device based on three-wavelength laser and dual detectors according to claim 1 is characterized in that: The electrical detector out-of-plane receiving unit comprises: A plurality of first photodetectors and a plurality of second photodetectors, wherein the first photodetectors and the second photodetectors are respectively fixed at different spatial positions on opposite sides of the monitoring device; The out-of-plane spatial position is configured to capture scattered light generated after multi-angle asymmetric laser irradiation.

4. The multi-angle out-of-plane detection device based on three-wavelength laser and dual detectors according to claim 1 is characterized in that: The stray light suppression housing unit comprises: Interior coating; An optical path channel, including an air inlet, an air outlet and multiple laser incident ports; An internal light blocking structure is configured to block non-target light paths.

5. The multi-angle out-of-plane detection device based on three-wavelength laser and two detectors according to claim 4 is characterized in that: The inner wall coating is made of carbon nanotube composite light-absorbing material.

6. The multi-angle out-of-plane detection device based on three-wavelength laser and two detectors according to claim 1 is characterized in that: Also includes: The signal processing unit is configured to calculate the particle size distribution and concentration based on the difference in the intensity of the scattered light at multiple angles collected by the out-of-plane detector.

7. The multi-angle out-of-plane detection device based on three-wavelength laser and two detectors according to claim 6 is characterized in that: The signal processing unit includes: a noise compensation module configured to separate water vapor scattering noise based on the laser channel signal; The multi-dimensional fusion algorithm module is configured to correlate the three-wavelength scattered light intensity with the spatial angle difference of the two detectors to invert the particle size distribution.

8. A multi-angle out-of-plane detection method based on three-wavelength laser dual detectors is characterized by: The multi-angle out-of-plane detection device based on three-wavelength laser and dual detectors according to any one of claims 1 to 7 comprises: The three-wavelength laser beam is used to asymmetrically illuminate the particle group to be measured from multiple angles; Synchronously collecting multi-dimensional scattered light signals using a first photodetector and a second photodetector arranged in different spatial planes; Filtering background noise through stray light suppression housing units; Correlation analysis of particle size and concentration based on multi-angle scattered light intensity.

9. The method for multi-angle out-of-plane detection based on three-wavelength laser and dual detectors according to claim 8, characterized in that: The three-wavelength laser beam comprises: a first short-wavelength beam sensitive to submicron particles; a second medium-wavelength beam sensitive to micronized particles; A third-longest wavelength beam with high ambient penetration.

10. The multi-angle out-of-plane detection method based on three-wavelength laser dual detectors according to claim 8 is characterized in that: The multi-dimensional scattered light signal acquisition includes: Synchronously acquiring scattered light signals collected by the first photodetector and the second photodetector at different spatial positions; Based on the spatial isolation characteristics of the out-of-plane layout, the optical crosstalk noise between detectors is separated and eliminated.

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