A double-layer hemispherical shell atmospheric simulation and optical thickness synchronous detection system

Abstract

The application discloses a double-layer hemispherical shell atmospheric simulation and optical thickness synchronous detection system, belongs to the field of atmospheric optical measurement, and aims to solve the problems of single detection technology direction, poor data consistency and insufficient light path stability of existing detection technologies. The system adopts a multi-unit distributed layout and an integrated collaborative control architecture, and the core comprises an outer layer horizontal detection unit, an outer layer vertical detection unit, an inner layer horizontal detection unit and a data processing module. Each detection unit is composed of a laser transmitter and a laser power detector. The transmitter outputs stable laser with a wavelength of 632nm. The transmitter and the detector are coaxially aligned and fixedly installed at preset positions of the double-layer hemispherical shell in a one-to-one correspondence, so that multi-direction synchronous detection is realized. The data processing module calculates and outputs atmospheric optical thickness data in different directions in real time based on an in-situ calibration algorithm and an optical thickness formula.

Description

Technical Field

[0001] This invention belongs to the field of atmospheric optical measurement, specifically relating to a system for simultaneous detection of atmospheric simulation and optical thickness in a double-hemispherical shell. Background Technology

[0002] Atmospheric optical thickness, as a core physical quantity characterizing the atmosphere's ability to attenuate light radiation, directly affects the transmission, scattering, and absorption processes of light in the atmosphere. Its accurate detection is a crucial foundation for research and applications in multiple fields, including Earth science, astronomy, environmental monitoring, and optical remote sensing. In Earth science, atmospheric optical thickness data is an important parameter for analyzing global energy balance and climate change mechanisms. In environmental monitoring, it is closely related to atmospheric aerosol concentration and pollutant diffusion patterns, serving as a core indicator for assessing air quality. In optical remote sensing, accurate atmospheric optical thickness correction directly determines the accuracy of surface parameter inversion. In astronomical observation, real-time detection of upper-air atmospheric optical thickness is a prerequisite for eliminating atmospheric interference and improving the resolution of astronomical observations.

[0003] However, current technologies for detecting atmospheric optical thickness still have many limitations, making it difficult to meet the demand for accurate and comprehensive detection data in various fields:

[0004] First, traditional detection methods have inherent flaws. On-site observations rely on ground stations, satellites, or balloons carrying detectors. While these can acquire real-world environmental data, their spatiotemporal coverage is limited by geographical conditions (e.g., difficulty in deploying stations in oceans and deserts) and weather changes (e.g., rain and dust storms affecting observation effectiveness). Furthermore, they can only passively acquire current atmospheric conditions and cannot actively simulate multi-directional detection scenarios under specific optical thickness conditions. While theoretical model-based calculations can predict optical thickness under different atmospheric conditions, they rely on numerous assumptions. Key parameters such as aerosol particle size distribution, water vapor content, and gas composition are difficult to input accurately, leading to significant discrepancies between model calculations and actual conditions. Additionally, they cannot intuitively present the physical processes of light propagation in different directions, hindering in-depth analysis of the spatial heterogeneity of atmospheric optical properties.

[0005] Secondly, the detection systems of existing laboratory simulation devices have significant shortcomings. To overcome the limitations of field observation, various atmospheric environment simulation devices have emerged, but the supporting optical thickness detection systems generally have design flaws: First, the detection direction is singular. Most devices only have a single horizontal or vertical detection path, which can only obtain optical thickness data in a specific direction. However, the propagation of light radiation in the actual atmosphere is multidirectional, and the distribution of atmospheric composition and the diffusion state of particulate matter differ in different directions, resulting in significant spatial heterogeneity in optical thickness distribution. Data from a single direction cannot comprehensively reflect the overall situation of atmospheric optical characteristics and is difficult to support the study of complex atmospheric optical processes. Second, the compatibility between the detection module and the simulation device is poor. After installation, some detection equipment is prone to damaging the airtightness of the simulation environment or interfering with the uniform distribution of particulate matter inside the spherical shell, thereby affecting the accuracy and reliability of the detection data.

[0006] Furthermore, existing multi-directional detection technologies suffer from severe stray light interference, low optical path adjustment accuracy, and insufficient data consistency. Conventional detection structures lack low-reflection extinction treatment, making them susceptible to stray radiation from ambient light, which superimposes onto the detection optical path and causes measurement errors. Additionally, the lack of a fine-tuning angle structure results in poor coaxial alignment accuracy between the transmitter and detector. A few multi-directional detection devices lack standardized in-situ calibration mechanisms, ignoring the impact of fluctuations in the laser's initial output power due to installation angle and position. The lack of precise pre-experiment calibration leads to inconsistent optical thickness calculation benchmarks and significant data deviations across different detection channels.

[0007] In summary, existing atmospheric optical thickness detection technologies have significant shortcomings in terms of comprehensiveness of detection orientation, precision of optical path adjustment, stray light suppression capability, data consistency, and compatibility with simulation devices. They lack an integrated multi-channel detection structure suitable for sealed spherical simulation cavities, making it difficult to perform refined optical detection at multiple locations within the cavity. Therefore, developing an atmospheric optical thickness detection system with multi-directional layout, high fine-tuning alignment precision, excellent stray light suppression, and accurate in-situ calibration capability is of urgent practical significance for promoting closed atmospheric simulation experiments and research on atmospheric optical properties. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing technologies, such as single detection direction, low optical path alignment accuracy, large stray light interference, poor data consistency, and inability to adapt to layered spatial detection with a double-hemispherical shell. This invention provides a double-hemispherical shell atmospheric simulation and optical thickness synchronous detection system. Based on a layered, sealed spatial layout with a double-coaxial hemispherical shell, this invention integrates multi-directional laser detection units and a precision adjustment and fixing structure. Combined with an anti-interference design and a standardized in-situ calibration algorithm, it achieves synchronous detection of atmospheric optical thickness in multiple directions, both horizontally and vertically, for both inner and outer layers. It features comprehensive detection dimensions, stable optical path, high detection accuracy, good data consistency, and strong cavity adaptability.

[0009] The specific technical solution of this invention is as follows:

[0010] A dual-hemispherical shell atmospheric simulation and optical thickness synchronous detection system includes an outer hemispherical shell, an inner hemispherical shell, a multi-directional detection unit, and a data processing module arranged coaxially. The outer and inner hemispherical shells are nested to form independent sealed outer and inner simulation spaces. The outer simulation space is adapted to be equipped with an aerosol medium to simulate the atmospheric environment at altitudes of 100km to 3km, and the inner simulation space is adapted to be equipped with an aerosol medium to simulate the near-surface atmospheric environment from 3km to the ground. The multi-directional detection unit includes an outer horizontal detection unit, an outer vertical detection unit, and an inner horizontal detection unit. Each detection unit consists of a laser emitter and a laser power detector, coaxially aligned and fixedly installed at a preset frame position on the dual hemispherical shell for synchronously acquiring laser power attenuation data from multiple directions. The data processing module is electrically connected to all laser power detectors, has a built-in in-situ calibration algorithm and an atmospheric optical thickness calculation model, receives real-time detection power data, and calculates the atmospheric optical thickness in different layers and directions.

[0011] The present invention has the following beneficial effects:

[0012] 1. Comprehensive detection dimensions, adaptable to dual-layer simulation cavity: This invention sets up three independent detection optical paths: outer longitudinal, outer transverse, and inner transverse, covering the inner and outer cavities and the two major detection directions of horizontal and vertical. It solves the defects of traditional detection equipment with single direction and inability to characterize the spatial heterogeneity of atmospheric optical thickness, and meets the detection needs of the Earth-Atmosphere-Light Hemisphere Simulation Experiment.

[0013] 2. High optical path stability and convenient alignment adjustment: It adopts a rigid fixing structure of 7075 aviation aluminum alloy, which has no deformation or displacement after installation; the receiver relies on the screw torque to finely adjust the tilt angle, accurately complete the coaxial alignment of the optical path, and with the locking structure, there is no optical path offset throughout the test, and the detection continuity is excellent.

[0014] 3. Strong stray light suppression capability and high detection accuracy: All structural components are coated with low-reflection matte black paint, which greatly reduces stray radiation interference; combined with a high-precision power detector and in-situ calibration mechanism, the system error is reduced, the uncertainty of optical thickness measurement is controllable, and the test data is highly reliable.

[0015] 4. Excellent structural adaptability, without damaging the simulated environment: The detection unit is installed without damage based on the original frame of the hemispherical shell, the cavity sealing is not affected, and the internal particulate matter is diffused evenly; the modular structure is easy to disassemble and assemble, and the black engineering plastic shell has both protection and heat dissipation functions, resulting in a long service life and low maintenance cost.

[0016] 5. Good data consistency and strong scalability: The parameters of multi-channel devices are unified, and the standardized in-situ calibration process eliminates system deviations caused by differences in installation and devices; the synchronous acquisition and real-time computing mode is adapted to the dynamic atmospheric simulation environment and can be widely used in simulation detection tests with different aerosol concentrations and different atmospheric conditions. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the double-layered hemispherical shell atmospheric simulation and optical thickness synchronous detection system of the present invention;

[0018] Wherein, 1-outer hemispherical shell; 2-third laser emitter; 3-second laser power detector; 4-inner hemispherical shell; 5-third laser power detector; 6-first laser power detector; 7-first laser emitter; 8-second laser emitter.

[0019] Figure 2 This is a structural diagram of the laser emitter. The first, second, and third laser emitters have the same structure. 9 represents the laser emitter; 10 represents the laser emitter mounting bracket.

[0020] Figure 3(a) shows the structural diagram of the first and third laser power detector modules. Wherein, 11-the body of the first laser power detector; 12-the mounting bracket for the laser power detector; 13-the angle adjustment component for the laser power detector.

[0021] Figure 3(b) is a structural diagram of the second laser power detector module. Wherein, 14 is the body of the second laser power detector; 15 is the mounting bracket for the second laser power detector. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the "Synchronous Detection System for Atmospheric Simulation and Optical Thickness of a Double-Layer Hemispherical Shell" of this invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of this invention.

[0023] The present invention achieves the above-mentioned objectives through the following technical solutions, the specific technical solutions of which are as follows:

[0024] like Figure 1As shown, a dual-hemispherical shell atmospheric simulation and optical thickness synchronous detection system includes an outer hemispherical shell 1, an inner hemispherical shell 4, a multi-directional detection unit, and a data processing module arranged coaxially. The outer hemispherical shell 1 and the inner hemispherical shell 4 are nested to form independent sealed outer simulation space and sealed inner simulation space. The outer simulation space is adapted to be equipped with aerosol media to simulate the atmospheric environment at an altitude of 100km to 3km, and the inner simulation space is adapted to be equipped with aerosol media to simulate the near-ground atmospheric environment from 3km to the ground. The multi-directional detection unit includes an outer horizontal detection unit, an outer vertical detection unit, and an inner horizontal detection unit. Each detection unit is composed of a laser emitter and a laser power detector, which are coaxially aligned and fixedly installed at a preset frame position on the dual hemispherical shell for synchronously acquiring laser power attenuation data from multiple directions.

[0025] The data processing module is electrically connected to all laser power detectors, and has a built-in in-situ calibration algorithm and atmospheric optical thickness calculation model. It receives real-time detection power data and calculates atmospheric optical thickness in different layers and directions.

[0026] The atmospheric optical thickness calculation model is based on the Beer-Lambert law. This law describes the energy attenuation of a monochromatic parallel beam passing through a uniform attenuating medium, and its general expression is:

[0027] ;

[0028] Taking the natural logarithm of both sides of the equation and transforming it, we can obtain the atmospheric optical thickness. The general calculation formula is:

[0029] ;

[0030] in, This represents the initial output power of the laser emitter (obtained through in-situ calibration). This represents the real-time received power of the laser power detector after the laser passes through a simulated atmospheric medium. The physical meaning of is the total extinction effect of the medium on radiation along the optical path, which is numerically equal to the integral of the scattering extinction coefficient and the absorption extinction coefficient along the path, and is dimensionless.

[0031] In the application scenario of this system, since the simulated atmospheric medium inside the double-layered hemispherical shell is in a uniformly mixed state and the distance between the transmitter and the detector is fixed, under the premise of ignoring the energy loss caused by the geometric divergence of the beam (i.e., assuming that the energy density of the beam cross section does not decrease with distance), the attenuation of the detector's received power is entirely caused by the scattering and absorption of the atmospheric medium inside the cavity, which perfectly fits the physical model of monochromatic light attenuation based on Lambert's law.

[0032] Based on the aforementioned general mathematical model, for the three independent detection channels—outer vertical, outer horizontal, and inner horizontal—the data processing module calls the reference values ​​obtained from in-situ calibration for each channel. With real-time detection values By substituting the values ​​into the calculation formulas for the three corresponding directions, the atmospheric optical thickness in the outer vertical, outer horizontal, and inner horizontal directions can be calculated simultaneously. Among these,

[0033] Vertical optical thickness of the outer spherical shell ;

[0034] Horizontal optical thickness of outer spherical shell ;

[0035] Horizontal optical thickness of inner spherical shell ;

[0036] in, This represents the initial output power of the laser emitter. This is the detected value from the second laser power detector. This is the detected value from the first laser power detector. This is the detected value from the third laser power detector.

[0037] Furthermore, the outer hemispherical shell 1 has a diameter of 5m, and the inner hemispherical shell 4 has a diameter of 2m; both the outer hemispherical shell 1 and the inner hemispherical shell 4 are made of ultra-white glass and coated with an anti-reflection film, with an overall light transmittance of not less than 95%.

[0038] Furthermore, the outer horizontal detection unit includes a first laser emitter 7 and a first laser power detector 6. The first laser emitter 7 and the first laser power detector 6 are symmetrically installed on both sides of the outer hemispherical shell 1 in the horizontal direction and at a preset position on the horizontal circumference. The emitting end of the laser emitter is coaxially aligned with the detection center of the corresponding detector, which is used to cover the horizontal multi-directional optical thickness measurement of the outer simulated space. The outer vertical detection unit includes a second laser emitter 8 and a second laser power detector 3. The second laser emitter 8 is installed at the lower vertical end inside the outer hemispherical shell 1, and the second laser power detector 3 is installed at the top of the inner hemispherical shell 4. The two are coaxially aligned, which is used to measure the vertical optical thickness of the outer simulated space. The inner horizontal detection unit includes a third laser emitter 2 and a third laser power detector 5. They are symmetrically installed on both sides of the inner hemispherical shell in the horizontal direction and coaxially aligned, which is used to measure the horizontal optical thickness of the inner simulated space.

[0039] Furthermore, all laser emitters 7, 8, and 2 have the same laser wavelength, with an output wavelength of 632nm to 638nm, power stability <1% (48-hour RMS), output aperture diameter of 1.0mm, and beam divergence angle <0.6mrad; all laser power detectors have a detection accuracy of not less than 0.001mW, a detection band range of 400 to 1100nm, a receiving power range of 50nW to 50mW, a measurement uncertainty of ±3%, a response time <1μs, and an input aperture of Φ9.7mm.

[0040] like Figure 2 The diagram shows the structure of the laser emitters. The first laser emitter 7, the second laser emitter 8, and the third laser emitter 2 all have identical structures, each including a laser emitter 9 and a laser emitter mounting bracket 10. All laser emitters utilize a hoisting and fixing structure: the hoisting strut is connected and fixed to the outer hemispherical shell frame beam using countersunk hexagonal screws, and then the laser emitter 9 is fixed to the laser emitter mounting bracket 10 using countersunk hexagonal screws. The laser emitter mounting bracket 10 has an L-shaped structure, with one end fixed to the hoisting strut and the other end supporting the laser emitter 9 and positioning it in the emission direction. The laser emitter 9 is fitted with a 3D-printed, one-piece black engineering plastic protective shell, which combines heat dissipation, dust protection, and structural protection.

[0041] The laser power detector is fixed to the beam of the hemispherical shell frame structure by hexagonal screws. The tilt angle of the laser power detector can be changed by adjusting the installation torque of a single screw, so as to achieve precise coaxial alignment of the laser optical path.

[0042] Figure 3(a) shows the structural diagrams of the first and third laser power detector modules, and Figure 3(b) shows the structural diagram of the second laser power detector module. The first and third laser power detector modules have the same structure, including a first laser power detector body 11, a laser power detector mounting bracket 12, and a laser power detector angle adjustment component 13. The first laser power detector body 11 is mounted on the laser power detector mounting bracket 12, and the laser power detector angle adjustment component 13 is used to adjust the angle of the first laser power detector body 11. The second laser power detector module includes a second laser power detector body 14 and a second laser power detector mounting bracket 15, with the second laser power detector body 14 mounted on the second laser power detector mounting bracket 15.

[0043] Furthermore, all structural components of the multi-directional detection unit are made of 7075 aerospace aluminum alloy, which has high structural strength, light weight, and corrosion resistance. The surface of the structural components is uniformly coated with matte black paint, and the coating reflectivity is better than 2%, which effectively reduces the reflection and diffuse stray radiation of external light sources and reduces the interference of stray light on the detection accuracy.

[0044] Furthermore, the data processing module establishes electrical connections with all laser power detectors to collect and detect laser power data in real time. Under the premise of ignoring the energy attenuation of beam divergence, the laser energy received by the detector is only affected by the attenuation of the atmospheric medium.

[0045] Furthermore, the initial output power P0 of the laser emitter is obtained using an in-situ calibration method: after the system is installed and debugged, the simulated space of the double-layer hemispherical shell is emptied to a clean state free of particulate matter, each laser shines directly on the corresponding detector, and multiple sets of raw power data are continuously collected. After removing abnormal deviation values, the average value is taken as the calibration P0. After calibration, all fixing screws are tightened, and it is strictly forbidden to change the installation angle and installation position.

[0046] The core functional components and working mechanism of this invention are as follows:

[0047] 1. Laser detection unit:

[0048] The laser emitters of all three detection units are uniformly helium-neon lasers with a wavelength of 638nm, an output aperture diameter of 1.0mm, a beam divergence angle of <0.6mrad, a rated output power of 30.0mW, and a long-term power stability of <1% over 48 hours, ensuring a constant incident laser source reference. The laser power detectors utilize high-precision laser power meters with a detection band of 400~1100nm, a receiving range of 50nW~50mW, a resolution of up to 1nW, a measurement uncertainty of ±3%, and a response time of <1μs, enabling instantaneous capture of power attenuation changes after the laser penetrates the simulated atmosphere. All transceiver components are locked and fixed after installation, with no relative displacement, ensuring long-term stability of the optical path from a mechanical structural perspective.

[0049] 2. Data transmission and processing module:

[0050] The data transmission and processing module uses high-speed shielded cables to connect each laser power detector to the industrial control terminal, avoiding electromagnetic signal interference and ensuring real-time data transmission. The data processing module has built-in noise filtering and detector response correction algorithms. It first removes stray light noise and dark current interference from the raw data, and then retrieves the initial P0 power values ​​of each group calibrated in situ before the experiment, using the same optical thickness calculation formula.

[0051] τ = -ln(P / P0);

[0052] Complete the data calculation; assuming that the energy loss caused by beam divergence is ignored, the energy received by the detector is assumed to be affected only by atmospheric scattering and absorption attenuation, ensuring that the calculation model fits the experimental conditions.

[0053] 3. Standardized in-situ calibration mechanism:

[0054] To eliminate data errors caused by installation deviations and component differences, this invention establishes a strict in-situ calibration process: After the system installation and alignment are completed, the internal space of the double-layer hemispherical shell is emptied to ensure that the cavity is free of aerosols and suspended particles, and is in a clean and transparent state; after the laser is preheated and stabilized, the raw power of each transceiver unit is directly collected, and 15 sets of data are collected continuously. After removing abnormal fluctuation values, the arithmetic mean is taken as the P0 calibration value of that channel; after calibration, all fastening screws are locked, and the position and angle of the transceiver components must not be changed. The calibration error is controlled within ±0.5%, unifying the multi-channel calculation benchmark and improving data consistency.

[0055] The workflow of this system is as follows:

[0056] 1. Calibration and Installation Phase:

[0057] All laser emitters and laser power detectors of the detection units are fixed to preset installation positions via standardized interfaces. The coaxiality of each unit is calibrated using a coaxial alignment adjustment mechanism to ensure precise matching and constant relative position between the laser power detector's detection surface and the laser incident direction. The simulated space is emptied to a clean state, and each laser emitter is activated, allowing each laser to directly illuminate its corresponding laser power detector. Each laser power detector continuously collects 15 sets of initial power data. Outliers exceeding ±0.001mW are removed, and the average value is taken as the P0 calibration value for that detection unit, stored in the data processing module, and locked. Data transmission cables and power are connected, and the interface sealing is checked to complete system deployment. This combination of in-situ calibration and fixed layout completely eliminates the impact of installation deviations and relative displacements on P0 measurement and optical path stability, ensuring detection reliability.

[0058] 2. Parameter setting stage:

[0059] According to the experimental requirements, the data acquisition frequency is set through the control terminal; the pre-calibrated P0 values ​​are called to complete the benchmark setting for optical thickness calculation, ensuring that the calculation benchmark is consistent with the actual working state of the detector.

[0060] 3. Detection and execution phase:

[0061] The atmospheric environment simulation process of the double-hemisphere shell simulation device is started. Preset concentrations of particulate matter are filled into the inner and outer simulated spaces. After the particulate matter concentration stabilizes, the detection system is started. All laser emitters simultaneously emit 632nm lasers. After the laser passes through the corresponding simulated atmospheric space, it is simultaneously received by each group of power detectors, realizing synchronous detection in multiple directions: horizontal in the outer layer, vertical in the outer layer, and horizontal in the inner layer.

[0062] 4. Data processing and output stage:

[0063] The data processing module performs noise filtering and detector response correction on the collected raw data, calls the corresponding transmitter's P0 calibration value, calculates optical thickness data in different directions using the optical thickness formula, generates data tables and trend graphs, outputs them to the control terminal in real time, and stores the raw data and processing results for subsequent traceability and analysis. After the detection is completed, the transmitter power is turned off, and the detection process is completed.

[0064] This invention only limits the multi-directional optical thickness detection layout, precise optical path alignment structure, stray light suppression structure, in-situ calibration process, and atmospheric optical thickness calculation method adapted to a double-layered hemispherical shell cavity. The atmospheric environment creation structures and devices within the double-layered simulation space, such as aerosol filling, particulate matter placement, gas replacement, and concentration control, are implemented by separate supporting equipment and are protected by separate patents; therefore, they are not within the scope of this invention. This invention only utilizes a layered, sealed simulation space where aerosol placement has been completed to achieve synchronous multi-directional atmospheric optical thickness detection.

[0065] Based on the above-mentioned technical architecture, this invention matches a double-layered hemispherical shell sealed layered cavity structure to build a multi-channel synchronous detection system. Each detection unit is fixedly installed at a preset frame position of the double-layered hemispherical shell. The three sets of detection optical paths, namely the outer horizontal, outer vertical, and inner horizontal, work together to realize synchronous acquisition of laser power in multiple directions, accurately complete the atmospheric optical thickness calculation and detection.

[0066] The data processing module establishes an electrical connection with all laser power detectors, incorporates noise filtering, response correction algorithms and in-situ calibration procedures, and completes real-time calculation of multi-channel optical thickness based on calibration reference values. It unifies calculation standards, eliminates installation and device deviations, and improves the consistency of multi-channel detection data.

[0067] Furthermore, the present invention provides the following specific embodiments,

[0068] (a) Fixed structural components:

[0069] All mechanical structural components are made of 7075 aviation aluminum alloy, anodized and then coated with matte black paint. The coating reflectivity is ≤2% (i.e., the energy reflected by the coating to incident light does not exceed 2% of the total energy of the incident light). The low-reflection light absorption treatment effectively suppresses external light source reflection and diffuse stray radiation from the inner wall of the cavity, reducing the interference of stray light on the detection accuracy. The laser emitting unit is fixed by a hoisting support rod and locked with M6 and M4 countersunk hexagonal screws. The laser receiving unit is fixed at multiple points with 7 M4 screws. The detector tilt angle is finely adjusted by the torque difference, and the coaxial alignment error is ≤±0.1°. The protective shell of the laser emitter is made of 3D printed black engineering plastic, integrally molded, sealed and dustproof, with reserved heat dissipation slots to ensure heat dissipation of the power module.

[0070] (ii) Laser emitter:

[0071] The laser emitter in this embodiment is model Bios638-30D, with the following core parameters: laser wavelength 638nm, output aperture diameter 1.0mm, beam divergence angle <0.6mrad, rated output power 30.0mW, 48-hour root mean square power stability <1%, suitable for long-term continuous test work, and the light source output is stable with no obvious fluctuations.

[0072] (III) Laser power detector:

[0073] In this embodiment, the laser power detector selected is the S120C laser power meter. Its core parameters are: detection band range of 400~1100nm, receiving power range of 50nW~50mW, measurement resolution of 1nW, measurement uncertainty of ±3%, response time of <1μs, and input aperture of Φ9.7mm. It can quickly capture weak laser power changes and is suitable for high-precision attenuation detection scenarios.

[0074] (iv) Data Processing Module:

[0075] The detector uses shielded cables to transmit data between the detector and the industrial computer, which is resistant to electromagnetic interference. It has a built-in moving average filtering algorithm to eliminate detection noise. It is equipped with dedicated data processing software that supports parameter setting, real-time acquisition, automatic calculation of optical thickness, data visualization and local storage. The calculation formula is τ=-ln(P / P0), which conforms to the atmospheric optical attenuation detection standard.

[0076] The standardized calibration procedure of this invention is as follows (performed before the experiment, in situ):

[0077] 1. Completely empty the double-layered hemispherical shell simulation space and ventilate it to a clean state to ensure that no particulate matter interferes with the P0 calibration.

[0078] 2. P0 in-situ calibration: Start each laser emitter and preheat for 30 minutes to ensure power stability. Let each group of lasers directly shine on the corresponding aligned detector. Collect 15 sets of initial power data for each detector continuously, remove deviation and abnormal values, calculate the average value as the P0 calibration value of the unit, enter it into the software and lock it. After calibration, fix the position and angle of the emitter and detector.

[0079] The system installation and debugging process of this invention is as follows:

[0080] 1. Optical path coaxial calibration: Install the outer horizontal, outer vertical, and inner horizontal detection units respectively. Adjust the detector angle by adjusting the torque of a single screw at the receiver end. Complete the coaxial alignment of the laser emission and reception optical paths group by group. After calibration, tighten all fixing screws to lock the relative position.

[0081] 2. In-situ power calibration: Clear the simulated space of the double-layer hemispherical shell to a clean and particulate-free state, and preheat the laser for 30 minutes to stabilize the power; for each group of optical path laser direct detectors, continuously collect 15 sets of raw power data, remove outliers with deviations exceeding ±0.001mW, take the arithmetic mean as the P0 calibration value of each channel, enter it into the data processing module for locking, and control the calibration error within ±0.5%.

[0082] 3. System integration test: Optical path test: The detector receiving power reaches more than 98% of the calibrated value; Optical thickness simulation attenuation test: The deviation between the calculated value and the theoretical value is ≤ ±2%, which meets the test accuracy requirements.

[0083] 4. System debugging:

[0084] (1) Power-on test: After powering on, check that all transmitters have stable power, the detectors transmit data normally, and there is no signal loss;

[0085] (2) Optical path test: Start all transmitters, and the receiving power of each group of detectors reaches more than 98% of the in-situ calibrated P0 value to confirm that the optical path is unobstructed, the coaxial alignment is qualified, and the relative position is stable.

[0086] (3) Calibration and verification: Call the P0 calibration value, simulate the attenuation through the filter, calculate the optical thickness and the deviation from the theoretical value ≤ ±2%, to ensure the system accuracy and consistency of multiple sets of data.

[0087] The system workflow of this invention is as follows:

[0088] 1. Experimental Preparation Stage: Fix the multi-directional detection unit to the preset installation position on the double-hemisphere shell, complete the optical path coaxial calibration and in-situ power calibration, call the built-in P0 calibration values ​​of each channel in the system, and complete the calculation reference initialization. Before the system operates, the double-hemisphere shell simulation space has been aerosolized by the matching independent atmosphere creation device to form a layered atmospheric environment that meets the experimental requirements.

[0089] 2. Multi-directional synchronous detection phase: All laser emitters synchronously emit fixed wavelength lasers. After the lasers penetrate the corresponding layer of simulated atmosphere, they are synchronously received by the detectors. The data processing module collects raw power data in real time. After noise filtering and response correction, the data is substituted into the optical thickness formula to calculate the optical thickness of the outer vertical, outer horizontal, and inner horizontal atmospheres, respectively.

[0090] 3. Data processing and completion stage: The system automatically generates an optical thickness data table and a real-time trend line graph, and stores the original detection data and processing results; after the experiment, all equipment power is turned off, and the detection process is completed.

[0091] Implementation effect verification:

[0092] The system and method of this embodiment achieve the following effects:

[0093] Detection coverage: The three modules combined with the 360° rotation function cover all detection angles in the horizontal direction from 0° to 360°, which can fully capture the spatial distribution differences of optical thickness inside the double hemispherical shell;

[0094] Accuracy and consistency: After calibration, the optical thickness calculation error is ≤±3%, and the deviation of the detection data of the three modules in the same simulated environment is ≤±2%, which meets the needs of multi-directional comparative research.

[0095] Compatibility: The system installation does not damage the airtightness of the double-layer hemispherical shell (the airtightness error of the simulated space is ≤0.01MPa), and the uniformity error of particulate matter concentration distribution is ≤5%, which does not affect the realism of the simulated environment.

[0096] Flexibility: Supports switching between fixed-point detection and scanning detection, and spectral bands can be activated individually or simultaneously to adapt to different atmospheric optical property research scenarios.

[0097] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. 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.

Claims

1. A system for simultaneous atmospheric simulation and optical thickness detection in a double-layered hemispherical shell, characterized in that, The system comprises an outer hemispherical shell, an inner hemispherical shell, a multi-directional detection unit, and a data processing module, all coaxially arranged. The outer and inner hemispherical shells are nested together to form independent, sealed outer and inner simulation spaces. The outer simulation space is equipped with aerosol media to simulate the atmospheric environment at altitudes from 100 km to 3 km, while the inner simulation space is equipped with aerosol media to simulate the near-surface atmospheric environment from 3 km to the ground. The multi-directional detection unit includes an outer horizontal detection unit, an outer vertical detection unit, and an inner horizontal detection unit. Each detection unit consists of a laser emitter and a laser power detector, coaxially aligned and fixedly installed at a predetermined frame position on the double hemispherical shell. This unit is used to synchronously collect laser power attenuation data from multiple directions. The data processing module is electrically connected to all laser power detectors, incorporates an in-situ calibration algorithm and an atmospheric optical thickness calculation model, receives real-time detection power data, and calculates the atmospheric optical thickness in different layers and directions.

2. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, The outer hemispherical shell has a diameter of 5m, and the inner hemispherical shell has a diameter of 2m. Both the outer and inner hemispherical shells are made of ultra-white glass and coated with an anti-reflective film, with an overall light transmittance of not less than 95%.

3. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, The outer horizontal detection unit includes a first laser emitter and a first laser power detector. The first laser emitter and the first laser power detector are symmetrically installed on both sides of the outer hemispherical shell in the horizontal direction and at a preset position on the horizontal circumference. The emitting end of the laser emitter is coaxially aligned with the detection center of the corresponding detector, and is used to cover the horizontal multi-directional optical thickness measurement of the outer simulated space. The outer vertical detection unit includes a second laser emitter and a second laser power detector. The second laser emitter is installed at the lower vertical end inside the outer hemispherical shell, and the second laser power detector is installed at the top of the inner hemispherical shell. The two are coaxially aligned and are used to measure the vertical optical thickness of the outer simulated space. The inner horizontal detection unit includes a third laser emitter and a third laser power detector, which are symmetrically installed on both sides of the inner hemispherical shell in the horizontal direction and are coaxially aligned, and are used to measure the horizontal optical thickness of the inner simulated space.

4. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 3, characterized in that, The first, second, and third laser emitters have the same laser wavelength, with an output wavelength of 632nm to 638nm, power stability of <1%, an output aperture diameter of 1.0mm, and a beam divergence angle of <0.6mrad. All laser power detectors have a detection accuracy of no less than 0.001mW, a detection wavelength range of 400 to 1100nm, a receiving power range of 50nW to 50mW, a measurement uncertainty of ±3%, a response time of <1μs, and an input aperture of Φ9.7mm.

5. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, The laser emitter of the multi-directional detection unit adopts a hoisting and fixing structure. The hoisting support rod is connected to the outer hemispherical shell frame structure beam by countersunk hexagonal screws, and then the laser emitter is locked to the fixed base plate by countersunk hexagonal screws. The laser emitter is equipped with a 3D printed one-piece black engineering plastic protective shell.

6. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, The laser emitter is fixed to the beam of the hemispherical frame structure by hexagonal screws, and the tilt angle of the laser power detector is changed by adjusting the installation torque of a single screw.

7. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, All structural components of the multi-directional detection unit are made of 7075 aerospace aluminum alloy; the surface of the structural components is uniformly coated with matte black paint, and the hemispherical reflectivity of the coating is less than 2%.

8. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, The atmospheric optical thickness calculation model is as follows: Atmospheric optical thickness at different locations is calculated using the following formula: Vertical optical thickness of the outer spherical shell ; Horizontal optical thickness of outer spherical shell ; Horizontal optical thickness of inner spherical shell ; in, This represents the initial output power of the laser emitter. This is the detected value from the second laser power detector. This is the detected value from the first laser power detector. This is the detected value from the third laser power detector.

9. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 8, characterized in that, The initial output power of the laser emitter In-situ calibration algorithm was used to obtain the following data: After the system installation and debugging were completed, the double-layered hemispherical shell simulated space was emptied to a clean, particulate-free state. Each laser emitter directly shone on its corresponding laser power detector, and multiple sets of raw power data were continuously collected. After removing abnormal deviation values, the average value was taken as the calibration result. .

10. The system for simultaneous atmospheric simulation and optical thickness detection of a double-layered hemispherical shell according to claim 1, characterized in that, The data processing module uses shielded cables to connect each laser power detector to the industrial control terminal.

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