FSM-Synchronized TDLAS-Based Three-Dimensional Gas Detection Apparatus for Three-Dimensional Gas Distribution Monitoring, Mountable on an Unmanned Vehicle

Abstract

A TDLAS-based three-dimensional gas detection device for detecting a specific gas in an ambient environment according to the present invention includes a laser light source unit that illuminates a WMS laser signal of a 2f / 1f scale through current modulation, an FSM steering unit that synchronizes an FSM scanning angle with the modulation phase of the WMS, a detector unit for receiving light, a distance calculation unit that calculates the beam path length (L) of the laser detected by the detector unit for each laser illumination shot, and a correction unit that periodically corrects the 2f / 1f signal scale in the WMS.

Description

Technology Field

[0001] The present invention is the result of a project (Project Name: Commercialization of a long-distance hazardous gas detection sensor mounted on an unmanned vehicle using the TDLAS method, Sub-project No.: B0080423002796) carried out with support from the 'Green New Industry Commercialization Support Project' promoted by the Ministry of Environment and operated by the Korea Environmental Industry & Technology Institute. The present invention relates to an unmanned vehicle-mounted FSM-synchronized TDLAS-based 3D gas detection device capable of rapidly reconstructing a spatial gas concentration distribution using TDLAS (Tunable Diode Laser Absorption Spectroscopy) of the Wavelength Modulation Spectroscopy (WMS) method for gas detection. Background Technology

[0002] Traditionally, various sensors and devices have been used in industrial sites, indoor environmental monitoring, and research facilities to determine gas leaks or detect hazardous gases. A diverse range of gas measurement technologies exists, including patented chemical sensors, infrared sensors, and optical sensors.

[0003] Conventional gas detection systems had limitations in that they measured only the gas concentration at a single point from a fixed location. Furthermore, even when using mobile sensors, it was common practice to measure only two-dimensional distributions. There is a need for the development of technology to accurately measure and visualize gas distribution in three-dimensional space.

[0004] In addition, existing portable or stationary TDLAS gas sensors only measure gas concentration in a specific direction, making it difficult to identify gas leak points and diffusion paths in three dimensions over a wide area.

[0005] To address this, LiDAR or drone-based scanning methods have been developed, but most of them rely on elastic scattering or image-based estimation methods and have the problem of failing to achieve spectroscopic precision. Meanwhile, product families such as RMLD (Remote Methane Leak Detector) utilize TDLAS, and while gas detection in a specific direction is possible with a single aiming method, there were limitations in accurately determining where gas is detected at a specific point or in which space, and in quantifying the amount of leakage in 3D space. The problem to be solved

[0006] The present invention aims to provide a gas detection device capable of producing a high-resolution 3D gas concentration map in real time through 3D gas distribution reconstruction using scan data.

[0007] The present invention aims to provide a gas detection device capable of creating a three-dimensional gas detection map of space through a detection sensor mounted on a mobile robot, moving away from a method of measuring gas detection at a single fixed point.

[0008] In addition, the present invention aims to provide a three-dimensional gas detection device capable of specifying a specific gas detection location in space. means of solving the problem

[0009] According to one embodiment of the present invention for achieving the above objective, a TDLAS-based 3D gas detection device for detecting a specific gas in an ambient environment comprises: a laser light source unit that illuminates a distributed feedback (DFB) laser corresponding to the absorption line of the specific gas, and illuminates by generating a wavelength modulation spectroscopy (WMS) laser signal of a 2f / 1f scale through current modulation; an FSM steering unit that steers the laser beam direction of two axes ((θx, θy)) generated by the laser light source unit to scan at 1 kHz or higher, and synchronizes the Fast Steering Mirror (FSM) scanning angle with the modulation phase of the WMS; a detection unit for receiving light reflected back from the laser irradiated by the laser light source unit; and a distance calculation unit that calculates the beam path length (L) of the laser illuminated by the laser light source unit and detected by the detection unit for each laser illumination shot using a LiDAR, a stereo camera, or a Simultaneous Localization And Mapping (SLAM) module. To periodically correct the 2f / 1f signal scale in WMS, it includes a correction unit that corrects the 2f / 1f signal scale by performing compensation based on whether there is an abnormality in the reflected signal using RAM (Residual Amplitude Modulation) measurements and an optical output monitor, and by realigning the scale to match the correct signal in a reference path using a reference cell with a known concentration.

[0010] In one embodiment, the distance calculation unit stores each measurement value along with metadata including information on the two axes (θx, θy) and the beam path length (L).

[0011] In one embodiment, the detection unit detects a signal by using a lock-in amplifier or digital lock-in (DSP) to extract a 1f signal component, which is a component that locks the detection signal to a reference frequency, and a 2f signal component, which is a component that locks the detection signal to a frequency that is twice the frequency of the reference frequency.

[0012] In one embodiment, the TDLAS-based 3D gas detection device further includes a gas 3D reconstruction operation unit that constructs the integral concentration for each FSM scan path of the FSM steering unit into a line integral matrix and reconstructs it into a 3D concentration field of the specific gas using an ART or SART tomography algorithm, and the gas 3D reconstruction operation unit calculates the leakage amount of the specific gas using wind speed information.

[0013] In one embodiment, the TDLAS-based 3D gas detection device is mounted on a mobile device, and as the mobile device moves to multiple points, the TDLAS-based 3D gas detection device determines the intersection point of the laser irradiation paths where gas is detected at different points as a gas detection point based on whether gas is detected on multiple laser irradiation paths measured at one point and whether gas is detected on multiple laser irradiation paths measured at another point. In this case, a first gas concentration measurement result is obtained through laser irradiation in each measurement direction at a predetermined angle according to a first irradiation direction in the horizontal direction at one point, and a second gas concentration measurement result is obtained through laser irradiation in each measurement direction at a predetermined angle according to a second irradiation direction in the vertical direction at one point. Then, based on the first gas concentration measurement result and the second gas concentration measurement result at one point and multiple points different from one point, the intersection point of each measurement direction where gas is detected is calculated to obtain a 3D gas detection result at the location to be detected.

[0014] In one embodiment, the TDLAS-based 3D gas detection device is mounted on a mobile device, and as the mobile device moves to multiple points, the TDLAS-based 3D gas detection device determines whether gas is detected on multiple laser irradiation paths measured at one point and whether gas is detected on multiple laser irradiation paths measured at another point, and identifies the intersection point of the laser irradiation paths where gas is detected at different points as the gas detection point, wherein a gas concentration measurement result is obtained through laser irradiation in each measurement direction at a predetermined angle according to the irradiation direction in the horizontal direction at one point, and the intersection point of each measurement direction where gas is detected is calculated based on the gas concentration measurement result according to each measurement direction at a predetermined angle at the one point and multiple points other than the one point, thereby obtaining a gas detection result at the location to be detected. Effects of the invention

[0015] The TDLAS-based 3D gas detection device according to the present invention synchronizes the FSM steering unit’s FSM (Fast Steering Mirror) scanning angle with the modulation phase of the WMS, and through the synchronized measurement, phase errors and signal distortion occurring during FSM scanning are eliminated, thereby enabling precise spectrum measurement even while moving.

[0016] In addition, the TDLAS-based 3D gas detection device according to the present invention can convert the integrated concentration of the open path TDLAS into an average concentration through distance correction, thereby quantifying the actual leakage concentration.

[0017] In addition, the TDLAS-based 3D gas detection device according to the present invention can reconstruct the concentration distribution of the entire space without a multi-point sensor through 3D tomography-based reconstruction.

[0018] In addition, the TDLAS-based 3D gas detection device according to the present invention can be mounted on a mobile robot, and the TDLAS-based gas detection device attempts to detect gas from multiple angles, recognizes gas detection at a specific point and a specific angle based on the gas concentration detected in a specific direction, and recognizes gas detection at another specific point and another specific angle to identify the intersection point as a gas detection point, thereby having the effect of creating a three-dimensional gas detection map of space.

[0019] In addition, the TDLAS-based 3D gas detection device according to the present invention not only creates a movement map of the detection target space through position recognition of a mobile robot platform, but also displays previously detected gas detection locations within the area for priority management, thereby enabling the location to be inspected first when gas is detected in the future. Brief explanation of the drawing

[0020] FIG. 1 shows a schematic configuration of a TDLAS-based three-dimensional gas detection device according to one embodiment of the present invention. FIG. 2 illustrates an exemplary form of a mobile robot platform adopting a TDLAS-based three-dimensional gas detection device according to the present invention. FIG. 3 schematically illustrates a method for specifying a gas detection point of a gas detection device according to the present invention. Figure 4 shows the detection process of a TDLAS-based three-dimensional gas detection device according to the present invention. Specific details for implementing the invention

[0021] Preferred embodiments according to the present invention will be described in detail below with reference to the attached drawings. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, and should be interpreted in a meaning and concept consistent with the technical spirit of the present invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention.

[0022] Therefore, the embodiments described in this specification and the configurations illustrated in the drawings are merely the most preferred embodiments of the present invention and do not represent all of the technical ideas of the present invention; thus, it should be understood that various equivalents and modifications that can replace them may exist at the time of filing this application.

[0023] FIG. 1 shows a schematic configuration of a TDLAS-based three-dimensional gas detection device according to one embodiment of the present invention.

[0024] First, the TDLAS-based 3D gas detection device (100) according to the present invention adopts a function that synchronizes the FSM scanning angle and the laser modulation phase (WMS phase) at the hardware level and performs path length correction based on distance estimation using LiDAR, stereo, and SLAM. In addition, the TDLAS-based 3D gas detection device (100) according to the present invention aims to provide a system capable of stably calculating high-resolution 3D gas concentration maps and leak locations and amounts in real time, even in an unmanned vehicle environment, by correcting RAM and optical output drift in real time and providing an algorithm for restoring 3D gas distribution and calculating leak amounts using scan data.

[0025] To this end, the TDLAS-based 3D gas detection device (100), with reference to FIG. 1, includes a laser light source unit (110), an FSM steering unit (120), a detection unit (130), a distance calculation unit (140), a correction unit (150), and a gas 3D reconstruction calculation unit (160) to detect a specific gas in the surrounding environment.

[0026] The laser light source (110) illuminates a distributed feedback (DFB) laser corresponding to the absorption line of the specific gas, and generates a wavelength modulation spectroscopy (WMS) laser signal of the 2f / 1f scale through current modulation to illuminate.

[0027] The laser light source (110) irradiates a DFM (distributed feedback) laser corresponding to the absorption line of a specific gas, for example, CH₄ 1653 nm, NH₃ 1532 nm, etc., by creating a 2f / 1f scale WMS (wavelength modulation spectroscopy) laser signal through current modulation.

[0028] The FSM steering unit (120) is steered so as to scan the laser beam direction of two axes ((θx, θy)) generated from the laser light source unit (110) at a rate of several kHz or more, in one embodiment at a rate of 1 kHz or more, and synchronizes the FSM (Fast Steering Mirror) scanning angle with the modulation phase of the WMS.

[0029] Meanwhile, the FSM steering unit (120) can be synchronized with the WMS modulation phase of the laser light source unit (110) through an FPGA or a high-speed timer circuit.

[0030] The detector (130) functions to receive light that is reflected back from a laser irradiated from a laser light source (110). The detector (130) may include a light receiving telescope or an InGaAs detector. Meanwhile, the detector (130) may use lock-in amplification or digital lock-in (DSP) to extract a 1f signal component, which is a component that locks the detection signal to a reference frequency, and a 2f signal component, which is a component that locks the detection signal to a frequency that is twice the reference frequency, thereby enabling the detection of a signal.

[0031] The distance calculation unit (140) calculates the beam path length (L) of the laser that is illuminated from the laser light source and detected by the detection unit using a LiDAR, a stereo camera, or a SLAM (Simultaneous Localization And Mapping) module for each laser illumination shot. At this time, the distance calculation unit (140) may store each measurement value together with metadata including information on the two axes (θx, θy) and the beam path length (L).

[0032] And the correction unit (150) performs compensation based on whether there is an abnormality in the reflected signal using RAM (Residual Amplitude Modulation) measurements and an optical output monitor to periodically correct the 2f / 1f signal scale in WMS, and corrects the 2f / 1f signal scale by realigning the scale to match the correct signal in the reference path using a reference cell with a known concentration. And, the correction unit (150) may periodically insert a reference cell or a mini MPC (Multi-Pass Cell).

[0033] In addition, the correction unit (150) may perform RAM correction by periodically inserting internal standard warnings.

[0034] The gas 3D restoration operation unit (160) functions to construct the integral concentration for each FSM scan path of the FSM steering unit (120) into a line integral matrix and to restore it into a 3D concentration field of the specific gas using an ART or SART tomography algorithm.

[0035] In addition, the gas 3D restoration calculation unit (160) may be able to calculate the leakage amount of the specific gas using wind speed information (U, V, W).

[0036] In addition, the TDLAS-based 3D gas detection device (100) can be mounted on a UAV / UGV, etc., and in this case, it may additionally include a control unit and a communication unit that synchronize with the position and attitude (GNSS / IMU) of the UAV / UGV and provide a laser safety control (distance-based output limiting), ROS2, etc., and a communication interface.

[0037] The TDLAS-based 3D gas detection device (100) is mounted on a UAV / UGV, etc. through this configuration and sequentially performs the corresponding functions in the order of FSM scan pattern setting, WMS phase synchronization, 2f / 1f measurement, distance correction, 3D gas concentration reconstruction, and leakage amount calculation.

[0038] FIG. 2 illustrates an exemplary form of a mobile robot platform adopting a TDLAS-based three-dimensional gas detection device according to the present invention.

[0039] Referring to FIG. 2, the mobile robot platform (200) is equipped with a driving motor, a control unit, a power supply unit, a communication module, etc., and can move autonomously or semi-autonomously indoors and outdoors. Additionally, the mobile robot platform (200) may be additionally equipped with an obstacle detection and avoidance system.

[0040] Additionally, the mobile robot platform (200) may be provided with a vibration reduction device or support to stably operate the TDLAS-based gas detection device (100).

[0041] Additionally, the mobile robot platform (100) is equipped with a sensor module on a four-wheel drive autonomous driving robot. The mobile robot platform (100) or the TDLAS-based gas detection device (100) may be configured to enable position recognition and mapping by including a LiDAR sensor that performs SLAM, an IMU, GPS, etc.

[0042] In addition, the mobile robot platform (200) may include a location recognition unit and a map storage unit.

[0043] The position recognition unit functions to recognize the movement position of the mobile robot platform at the location to be detected and the direction of the mobile robot platform. Through the position of the mobile robot platform provided by the position recognition unit, the gas detection device is able to verify the measurement position measured by the detection unit, the distance calculation unit, and the correction unit.

[0044] In addition, the location recognition unit can recognize the movement position and direction based on the relative position with the location recognition indicators installed at multiple locations of the location to be detected. Through this, the mobile robot platform (200) can determine the movement direction and movement position of the mobile robot platform based on the detection map previously stored in the map storage unit corresponding to the location to be detected and the relative position information with the location recognition indicators. In another example, the mobile robot platform (200) can determine an arbitrary movement direction and movement position without including the map information of the location to be detected stored in advance, create and update the detection map of the location to be detected at the corresponding point, and determine the movement direction and movement position of the mobile robot platform based on the detection map created and stored in the map storage unit and the relative position information with the location recognition indicators.

[0045] Meanwhile, the TDLAS-based gas detection device (100) is mounted on a mobile robot platform (200) and is combined with the mobile robot platform so that the laser irradiation direction to the measurement target can be changed at a predetermined range angle through an FSM steering unit, and has the function of measuring the gas concentration at a specific absorption wavelength through laser irradiation in the measurement direction.

[0046] Meanwhile, the TDLAS-based gas detection device (100) according to the present invention enables multi-point measurement, that is, measurement in multiple directions or angles, through the FSM steering unit (120). Through this, data is acquired from multiple angles where a laser beam is irradiated, and absorbance data is read in real time by providing a separate collection channel for each measurement beam. Then, the absorbance spectrum is analyzed in the processor to calculate the gas concentration (ppm or %). At the same time, it is matched with the position (3D coordinates) of the robot.

[0047] In addition, the TDLAS-based gas detection device (100) according to the present invention can generate a 3D gas distribution map using the detected gas locations. Concentration data collected from multiple points is processed using spatial interpolation or a machine learning-based spatial prediction technique to finally generate a 3D distribution map. The map can be transmitted to a local (robot-mounted PC) or remote server for visualization.

[0048] The acquisition of the three-dimensional gas detection result of the present invention will be explained in detail with reference to FIG. 3.

[0049] First, as explained above, if the beam path length (L) of the laser is calculated for each laser beam shot using a LiDAR, a stereo camera, or a SLAM (Simultaneous Localization And Mapping) module through the distance calculation unit (140), the gas detection device (100) can use a method of irradiating the laser in multiple directions from one location and calculating the distance to the detected gas for each beam shot without needing to measure at multiple locations.

[0050] However, when mounted on a UAV / UGV or the like, gas detection by the TDLAS-based 3D gas detection device (100) can be performed at multiple points, and in this case, more accurate gas detection location identification can be performed.

[0051] FIG. 3 schematically illustrates a method for specifying a gas detection point of a gas detection device according to the present invention.

[0052] Figure 4 exemplarily illustrates the detection process of a TDLAS-based three-dimensional gas detection device according to the present invention.

[0053] Referring to FIGS. 3 and 4, the gas detection device (100) can identify the intersection point of the laser irradiation paths where the gas detected at different points is detected as the gas detection point, based on whether gas is detected on a plurality of laser irradiation paths measured at any one point of the gas detection device and whether gas is detected on a plurality of laser irradiation paths measured at another arbitrary point.

[0054] For example, when the mobile robot platform (200) is positioned at the first measurement location (S11), information regarding the point and the direction the mobile robot platform is facing is transmitted to the gas detection device (100), and the gas detection device (100) irradiates the laser beam in multiple directions through the FSM steering unit and irradiates the laser at multiple angles, i.e., multiple directions, to check for gas detection in the corresponding direction (S12). Then, it checks whether gas is detected for each direction (S13).

[0055] At this time, the gas detection device (100) may randomly adjust the angle for laser irradiation at any point, or may sequentially adjust the angle in a specific direction.

[0056] Then, when the mobile robot platform (200) is positioned at the second measurement location (S14), information regarding the point and the direction the mobile robot platform is facing is transmitted to the gas detection device (100), and the gas detection device (100) irradiates the laser beam in multiple directions through the FSM steering unit and irradiates the laser at multiple angles, i.e., multiple directions, to check for gas detection in the corresponding direction (S15). Then, it checks whether gas is detected for each direction (S16).

[0057] Then, the direction in which gas is detected for each direction is crossed at two points or multiple points, and the crossed point is designated as the gas detection location (S17).

[0058] In one embodiment, the gas detection device (100) obtains a first gas concentration measurement result through laser irradiation in each measurement direction at a predetermined angle according to a first irradiation direction in the horizontal direction at any point and a second gas concentration measurement result through laser irradiation in each measurement direction at a predetermined angle according to a second irradiation direction in the vertical direction at any point, and calculates the intersection point of each measurement direction where gas is detected based on the first gas concentration measurement result and the second gas concentration measurement result at a plurality of points different from the arbitrary point, thereby obtaining a three-dimensional gas detection result at the location to be detected.

[0059] In addition, in another embodiment, the gas detection device (100) obtains gas concentration measurement results by laser irradiation in each measurement direction at a predetermined angle according to the irradiation direction in the horizontal direction at any one point, and calculates the intersection points of each measurement direction where gas is detected based on the gas concentration measurement results according to each measurement direction at a predetermined angle at the arbitrary one point and a plurality of other points, thereby obtaining gas detection results at the location to be detected. This process may be performed through the detection unit (130) of the gas detection device (100).

[0060] In addition, the gas detection device (100) according to the present invention stores the location where gas is detected at the location to be detected, and based on this, creates a gas distribution map of the location to be detected (S17), and can select the previously stored gas detection location as a priority monitoring target. That is, by creating a 3D or 2D gas distribution map, it is possible to check the history of gas generation in a specific area and take measures to inspect that area first when gas is detected in the future, or to conduct multiple inspections from various angles at multiple points. The created gas distribution map may be stored in a map storage unit or may be stored in a separate gas detection result map storage unit.

[0061] At this time, the gas detection device (100) generates a 3D gas distribution map of the location to be detected using a 3D gas distribution modeling algorithm. For example, the algorithm may be processed through a 3D mapping algorithm, interpolation, machine learning-based correction, etc.

[0062] A method for generating a 3D gas distribution map based on these 3D gas detection results can collect measurement data from a multi-point TDLAS-based gas detection device while a mobile robot platform moves, match the collected data with spatial coordinates—that is, the robot position—and then visualize it using 3D volume rendering or a mesh method. In addition, it may be possible to generate time-series 3D data by tracking changes in gas concentration over time.

[0063] In this way, the TDLAS-based 3D gas detection device according to the present invention synchronizes the FSM steering unit’s FSM (Fast Steering Mirror) scanning angle with the modulation phase of the WMS, and through the synchronized measurement, phase errors and signal distortions occurring during FSM scanning are eliminated, thereby enabling precise spectrum measurement even while moving.

[0064] In addition, the TDLAS-based 3D gas detection device according to the present invention can convert the integrated concentration of the open path TDLAS into an average concentration through distance correction, thereby quantifying the actual leakage concentration.

[0065] In addition, the TDLAS-based 3D gas detection device according to the present invention can reconstruct the concentration distribution of the entire space without a multi-point sensor through 3D tomography-based reconstruction.

[0066] In addition, the TDLAS-based 3D gas detection device according to the present invention can be mounted on a mobile robot, and the TDLAS-based gas detection device attempts to detect gas from multiple angles, recognizes gas detection at a specific point and a specific angle based on the gas concentration detected in a specific direction, and recognizes gas detection at another specific point and another specific angle to identify the intersection point as a gas detection point, thereby having the effect of creating a three-dimensional gas detection map of space.

[0067] In addition, the TDLAS-based 3D gas detection device according to the present invention not only creates a movement map of the detection target space through position recognition of a mobile robot platform, but also displays previously detected gas detection locations within the area for priority management, thereby enabling the location to be inspected first when gas is detected in the future.

[0068] As described above, although the present invention has been explained by limited embodiments and drawings, the present invention is not limited thereto, and it is obvious that various modifications and variations are possible within the scope of the technical spirit of the present invention and the equivalent scope of the claims described below by those skilled in the art to which the present invention belongs. Explanation of the symbols

[0069] 100: TDLAS-based 3D gas detection device 110: Laser light source 120: FSM Steering Unit 130: Detector 140: Distance Calculation Unit 150: Correction section 160: Gas 3D Restoration Computation Unit 200: Mobile Robot Platform

Claims

Claim 1 A TDLAS-based 3D gas detection device for detecting a specific gas in an ambient environment comprises: a laser light source unit that illuminates a distributed feedback (DFB) laser corresponding to the absorption line of the specific gas, and illuminates by generating a wavelength modulation spectroscopy (WMS) laser signal of a 2f / 1f scale through current modulation; an FSM steering unit that steers the laser beam direction of two axes ((θx, θy)) generated by the laser light source unit to scan at 1 kHz or higher, and synchronizes the Fast Steering Mirror (FSM) scanning angle with the modulation phase of the WMS; a detector unit for receiving light reflected back from a laser irradiated by the laser light source unit; a distance calculation unit that calculates the beam path length (L) of the laser illuminated by the laser light source unit and detected by the detector unit for each laser illumination shot using a LiDAR, a stereo camera, or a Simultaneous Localization And Mapping (SLAM) module; and, for periodically correcting the 2f / 1f signal scale in the WMS, A correction unit that performs compensation based on whether there is an abnormality in the reflected signal using RAM (Residual Amplitude Modulation) measurements and an optical output monitor, and corrects the 2f / 1f signal scale by realigning the scale to match the correct signal in a reference path using a reference cell with a known concentration;A TDLAS-based 3D gas detection device comprising, wherein the TDLAS-based 3D gas detection device is mounted on a mobile device, and as the mobile device moves to multiple points, the TDLAS-based 3D gas detection device identifies the intersection point of the laser irradiation paths where gas is detected at different points as the gas detection point based on whether gas is detected on multiple laser irradiation paths measured at an arbitrary point and whether gas is detected on multiple laser irradiation paths measured at another arbitrary point, wherein a gas concentration measurement result is obtained through laser irradiation in each measurement direction at a predetermined angle according to the irradiation direction in the horizontal direction at an arbitrary point, and the intersection point of each measurement direction where gas is detected is calculated based on the gas concentration measurement result according to each measurement direction at a predetermined angle at the arbitrary point and multiple other points, thereby obtaining a gas detection result at a location to be detected. Claim 2 A TDLAS-based three-dimensional gas detection device according to claim 1, wherein the distance calculation unit stores each measurement value together with metadata including information on the two axes (θx, θy) and the beam path length (L). Claim 3 A TDLAS-based 3D gas detection device according to claim 1, wherein the detection unit uses lock-in amplification or digital lock-in (DSP) to extract a 1f signal component, which is a component that locks the detection signal to a reference frequency, and a 2f signal component, which is a component that locks the detection signal to a frequency that is twice the harmonic of the reference frequency, and detects the signal. Claim 4 In claim 1, the TDLAS-based 3D gas detection device further comprises a gas 3D reconstruction operation unit that constructs the integral concentration per FSM scan path of the FSM steering unit into a line integral matrix and reconstructs it into a 3D concentration field of the specific gas using an ART or SART tomography algorithm. Claim 5 In claim 4, the gas 3D reconstruction computation unit is a TDLAS-based 3D gas detection device that calculates the leakage amount of the specific gas using wind speed information. Claim 6 The TDLAS-based 3D gas detection device according to claim 1 is mounted on a mobile device, and as the mobile device moves to multiple points, the TDLAS-based 3D gas detection device determines the intersection point of the laser irradiation paths where gas is detected at different points as a gas detection point based on whether gas is detected on multiple laser irradiation paths measured at one arbitrary point and whether gas is detected on multiple laser irradiation paths measured at another arbitrary point, wherein a first gas concentration measurement result is obtained through laser irradiation in each measurement direction at a predetermined angle according to a first irradiation direction in the horizontal direction at one arbitrary point, and a second gas concentration measurement result is obtained through laser irradiation in each measurement direction at a predetermined angle according to a second irradiation direction in the vertical direction at one arbitrary point, and the intersection point of each measurement direction where gas is detected is calculated based on the first gas concentration measurement result and the second gas concentration measurement result at one arbitrary point and multiple other points, thereby obtaining a 3D gas detection result at a location to be detected. Claim 7 delete

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