CN106841171A - The combined spectral detection method of detection is imported and exported for large and valuable kinds of goods - Google Patents

Abstract

The invention discloses a kind of combined spectral detection method that detection is imported and exported for large and valuable kinds of goods, the method is realized on combined spectral detector.The whole machine of instrument of combined spectral detector includes master controller, user mutual display screen, integrated multipath voltage-stabilized power supply, LIBS subsystems, range finding subsystem, cassette telescope, XRF subsystems and BLR subsystems.Combined spectral detection method includes two steps of long-range LIBS Rough Inspections and short range integrated spectral accurate measurement.The beneficial effects of the invention are as follows it realizes being detected while weight element；By LIBS, XRF and BLR combination, detected while realizing atom with macromolecular structure, while BLR and LIBS multiplexing spectrum channels can save the nonmetalloids such as hardware resource, the measurable sulphur of spectrum analysis of LIBS covering near-infrared sections.This instrument and method can solve the problem of cross-border kinds of goods determinand element and molecular characterization identification and joint inspection, realize hazardous material Site Detection in the cross-border typical kinds of goods quick discriminating such as large, valuable and kinds of goods.

Description

Combined Spectral Detection Method for Import and Export Inspection of Bulk and Valuable Goods

technical field

The invention relates to a laser spectrum detection method, in particular to a spectrum detection method using combined detection of atoms and molecules, which is suitable for non-destructive on-site import and export of bulk goods and valuables, and belongs to the field of photoelectric detection.

Background technique

At present, in the detection of cross-border goods, there is a lack of powerful and rapid measurement methods for the anti-counterfeiting inspection of typical goods such as bulk and valuables and the on-site non-destructive testing of harmful elements. Anti-counterfeiting detection and detection of harmful substances involves the joint detection and identification of elements and molecular structures, as well as the high-precision full-coverage detection of basic elements, which requires a combination of various measurement and analysis methods and technologies.

Among the optional detection techniques, laser-induced breakdown spectroscopy (abbreviated as LIBS) is a typical detection method for material elements, which has been applied in various fields of element detection. Its characteristic is that it can detect light elements and non-metallic elements. The disadvantage is that it is affected by the chemical matrix effect, and the accuracy of quantitative analysis is not very high. Laser Raman technology, especially bi-wavelength laser Raman (BLR for short) technology can effectively remove the influence of fluorescent substrates, and is especially suitable for molecular structure determination of polymer compounds. X-ray fluorescence spectroscopy (XRF for short) technology is a technology that can accurately measure elements, especially heavy elements, and is especially suitable for the determination of elemental content of valuable commodities.

Aiming at the needs of cross-border cargo anti-counterfeiting inspection and detection of harmful substances, the present invention proposes a combined spectrum detection instrument and method, combining LIBS and XRF to realize simultaneous detection of light and heavy elements; combining LIBS, XRF and BLR, Simultaneous detection of atomic and polymer structures can solve the problem of identification and joint inspection of elements and molecular structure features of cross-border goods, and realize rapid identification of bulk and valuable cross-border typical goods and on-site detection of hazardous substances in goods.

Contents of the invention

The purpose of the present invention is to provide a combined spectral detection method to realize the synchronous detection of light and heavy elements, atoms and polymers, so as to solve the problem of anti-counterfeiting of bulk cargo and rapid detection of valuables at customs ports.

The present invention is achieved like this:

The instrument of the combined spectrometer for the import and export detection of bulk and valuable goods mainly includes the main controller, user interactive display screen, integrated multi-channel regulated power supply, LIBS subsystem, ranging subsystem, cassette telescope, XRF subsystem and BLR subsystem.

Among them, the LIBS subsystem consists of LIBS signal acquisition mirror, pigtail, LIBS dichroic mirror, LIBS beam expander, timing controller, LIBS laser and four-channel spectrometer; the ranging subsystem consists of ranging laser, ranging beam expander, Composed of a half mirror and a range-finding polychromatic mirror; the cassette telescope is composed of a primary mirror, a secondary mirror and a secondary mirror drive mechanism; the XRF subsystem consists of an X-ray tube, an X-ray focusing mirror, an acquisition channel, an X-ray detector, a front Amplifier and spectrum analyzer; BLR subsystem consists of 808nm Raman laser, 785nm Raman laser, 785nm Raman probe, 808nm Raman probe, dual-wavelength Raman mirror, Raman lens, 785nm Raman receiving fiber, 808nm Raman Composed of Mann receiving fiber, 785nm Raman emitting fiber, 808nm Raman emitting fiber and fiber combiner, the BLR subsystem multiplexes the fourth channel of the four-channel spectrometer;

The integrated multi-channel regulated power supply contains a rechargeable lithium battery, and has two working modes of AC and DC. In the DC working mode, no external mains power is needed, and the internal lithium battery provides multiple centralized power supplies; in the AC working mode, it can be connected to the mains interface. It is used to charge the internal lithium battery, and the integrated multi-channel regulated power supply provides multiple centralized power supplies;

The multi-channel power supply integrated with multi-channel regulated power supply is to provide the working voltage of the main controller, user interactive display screen, LIBS laser, ranging laser, 808nm Raman laser, 785nm Raman laser and X-ray tube;

There is main control software in the main controller, which is used to control the user interactive display screen, timing controller, ranging laser, 808nm Raman laser, 785nm Raman laser, X-ray tube and secondary mirror drive mechanism; The channel spectrometer supplies power and receives and analyzes its output spectral signal; receives and analyzes the output data of the ranging sensor and spectrum analyzer; receives user instructions transmitted from the user interactive display screen and returns the test results such as data and charts required by the user;

The main optical axis, LIBS optical axis, ranging optical axis, ranging optical axis, XRF emitting optical axis and XRF receiving optical axis are all located in the same plane; LIBS optical axis and ranging optical axis are parallel and perpendicular to the main optical axis Optical axis; the ranging secondary optical axis is perpendicular to the ranging optical axis, that is, parallel to the main optical axis; the XRF emitting optical axis and XRF receiving optical axis are symmetrically distributed about the main optical axis;

The primary mirror of the clip-on telescope is fixed, and the secondary mirror can move along the main optical axis driven by the driving mechanism of the secondary mirror. The focal length of the telescope is the longest, at this time the laser emitted by the LIBS laser is focused on the remote test point by the cassette telescope; on the contrary, when the secondary mirror moves to the farthest distance from the primary mirror, the focal length of the cassette telescope is the shortest, at this time LIBS The laser emitted by the laser is focused and converged on the short-range test point by the card-type telescope; the short-range test point to the long-range test point is the LIBS test range, and within this range, the ranging subsystem is assisted to realize the LIBS self-focusing function; XRF and BLR Both are short-range tests, that is, the test points are short-range test points, that is, LIBS, XRF, and BLR short-range tests are all at the same target point; the short-range test point is installed with a short-range test point limit baffle, when the goods When the test object fits the baffle, the product test object is limited to the position of the short-range test point, which meets the requirements of LIBS, XRF, and BLR short-range tests;

There is a test window at the position of the whole instrument facing the main optical axis, so that the emitted beams and echo signals of LIBS, XRF and BLR can freely enter and exit the whole instrument;

The combined spectrometer for the import and export detection of bulk and valuable goods works in the following steps:

(1) Remote LIBS coarse inspection

The main controller issues a control command to start the ranging laser, and the continuous laser light emitted by the ranging laser travels along the ranging optical axis, expands the beam through the ranging beam expander, passes through the half mirror, is reflected by the ranging polychromatic mirror, and then follows the main beam. The axial direction penetrates into the center hole of the primary mirror of the clip-on telescope, is reflected by the secondary mirror, and then reflected by the primary mirror and focused on the long-distance cargo test object. Since the focal length of the cassette telescope does not match the distance of the cargo, it is Defocus state. The backscattered echo of the goods test object travels in the opposite direction along the main optical axis. It is first reflected by the primary mirror, then reflected by the secondary mirror, passes through the center hole, and travels along the distance measuring optical axis after being reflected by the distance measuring polychromatic mirror. After being reflected by the half-mirror, it travels along the secondary optical axis of distance measurement, and is received by the distance measurement sensor. The sensing signal of the distance measurement sensor is sent to the main controller for analysis, and the echo intensity value is obtained. The main controller sends an instruction to start the secondary mirror driving mechanism to drive the secondary mirror to move continuously along the main optical axis, change the focal length of the cassette telescope, and continuously test the echo intensity value. When the echo intensity reaches the peak value, the main controller sends an instruction to close the secondary mirror. The driving mechanism stops the movement of the secondary mirror and achieves a precise focusing state at this time;

In the state of precise focusing, the main controller sets the delay time d of the timing controller, and the timing controller first starts the LIBS laser, and then starts the four-channel spectrometer to expose and receive the echo signal of LIBS after the delay d; its working process for:

The pulsed laser emitted by the LIBS laser travels along the LIBS optical axis, expands the beam through the LIBS beam expander, and then travels along the main optical axis after being reflected by the LIBS dichroic mirror. The central hole is reflected by the secondary mirror, and then reflected by the primary mirror and focused to the long-distance cargo test object. The LIBS signal generated by the cargo test object travels in the opposite direction along the main optical axis, first reflected by the primary mirror, and then passed by the secondary mirror. Reflected, passed through the central hole, passed through the distance measuring polychromatic mirror, collected by the LIBS signal acquisition mirror, entered the four-channel spectrometer through the pigtail, passed through the grating, and the photoelectrically converted spectral data was sent to the main controller for storage and analysis;

The LIBS material analysis software program of the main controller analyzes the collected remote LIBS spectral data, and obtains the material element composition of the test object of the goods and the rough inspection value of the content. If it is considered to be no problem, the goods can be released; otherwise, if it is judged If it is suspicious, enter the next step of short-range precise measurement;

(2) Short-range comprehensive spectrum precision measurement

Move the combined spectrometer for import and export detection of bulk and valuable goods closer to the goods test object, so that the goods test object fits the limit baffle of the short-range test point, and the main controller sends an instruction to start the secondary mirror driving mechanism to drive the secondary mirror to move along the main optical axis To the position where the distance between the primary mirror and the secondary mirror is the farthest, at this time, the focal length of the clip-on telescope is the shortest, and the laser emitted by the LIBS laser will be focused on the short-range test point through the clip-on telescope;

The main controller sends an instruction, and the timing controller first starts the LIBS laser, and then after a delay d, starts the four-channel spectrometer to expose and receive the echo signal of LIBS;

The LIBS material analysis software program of the main controller analyzes the collected short-range LIBS spectral data, and obtains the element composition of the goods test object, including light, heavy elements, non-metallic elements, and metal elements, as well as the content value of each element;

The main controller sends an instruction to start the X-ray tube. The X-rays emitted by the X-ray tube travel along the XRF emission optical axis, and are focused to the short-range test point by the X-ray focusing mirror. The X-ray fluorescence signal generated by the goods test object travels along the XRF reception optical axis. , after being received by the X-ray detector through the acquisition channel, and then amplified by the preamplifier, it enters the spectrum analyzer for analysis, and the XRF spectrum data is sent to the main controller for storage and analysis;

The XRF material analysis software program of the main controller analyzes the collected short-range XRF spectral data, obtains the composition and precise content of the heavy elements of the goods test object, and integrates the element composition and content results with the LIBS short-range detection results, Obtain the composition and content of light and heavy elements, measure the composition and content of bulk goods and valuable goods, carry out anti-counterfeiting detection and establish a corresponding database;

The main controller issues an instruction to start the 785nm Raman laser. The 785nm continuous laser emitted by the 785nm Raman laser enters the 785nm Raman probe through the 785nm Raman emitting fiber, and passes through its internal 785nm interference filter to form a narrow linewidth laser. After being reflected by the dual-wavelength Raman mirror, it travels along the main optical axis and converges to the short-range test point through the Raman lens. The 785nm Raman probe enters the 785nm Raman receiving fiber after passing through its internal 785nm Rayleigh filter, and then enters the fourth channel of the four-channel spectrometer after passing through the fiber combiner. The Mann spectral data is sent to the main controller for storage and analysis;

The main controller sends an instruction to start the 808nm Raman laser, and the 808nm continuous laser emitted by the 808nm Raman laser enters the 808nm Raman probe through the 808nm Raman emitting fiber, and passes through its internal 808nm interference filter to form a narrow linewidth laser. After being reflected by the dual-wavelength Raman mirror, it travels along the main optical axis and converges to the short-range test point through the Raman lens. The 808nm Raman probe enters the 808nm Raman receiving fiber after passing through its internal 808nm Rayleigh filter, and then enters the fourth channel of the four-channel spectrometer after passing through the fiber combiner. The Mann spectral data is sent to the main controller for storage and analysis;

The BLR material analysis software program of the main controller analyzes the collected short-range 785nm and 808nm Raman spectral data, removes the fluorescence interference through the differential method, and obtains the high Molecular composition and content can be analyzed for toxic and harmful substances.

The beneficial effect of the present invention is that it provides a combined spectrum detection instrument and method, combining LIBS and XRF to realize simultaneous detection of light and heavy elements; combining LIBS, XRF and BLR to realize simultaneous detection of atomic and polymer structures At the same time, BLR and LIBS multiplexing spectral channels can save hardware resources, and the spectral analysis of LIBS covering the near-infrared range can measure non-metallic elements such as sulfur. The instrument and method can solve the problem of identification and joint inspection of elements and molecular structure characteristics of cross-border goods to be tested, and realize rapid identification of bulk and valuable cross-border typical goods and on-site detection of hazardous substances in goods.

Description of drawings

Fig. 1 is the structural schematic diagram of the combined spectrometer designed for the import and export detection of bulk and valuable goods in the present invention, in the figure: 1—the complete instrument; 2—four-channel spectrometer; 3—LIBS signal collecting mirror; 4—main light Axis; 5—LIBS dichroic mirror; 6—LIBS beam expander; 7—LIBS optical axis; 8—LIBS laser; 9—range laser; 10—distance optical axis; 11—distance Beam expander; 12—half mirror; 13—ranging polychromatic mirror; 14—fiber beam combiner; 15—ranging sensor; 16—distance measuring secondary optical axis; 17—primary mirror; 18 - 808nm Raman laser; 19 - 785nm Raman laser; 20 - central hole; 21 - 785nm Raman probe; 22 - 808nm Raman probe; 23 - secondary mirror; 24 - dual wavelength Raman Reflector; 25—X-ray tube; 26—X-ray focusing mirror; 27—XRF emission axis; 28—short-range test point; 29—XRF reception optical axis; 30—long-distance test point; 31 ——test window; 32—acquisition channel; 33—Raman lens; 34—X-ray detector; 35—preamplifier; 36—spectrum analyzer; 37—secondary mirror driving mechanism; 38— —main controller; 39—sequence controller; 40—user interactive display; 41—integrated multi-channel regulated power supply; 42—mains interface; 43—the fourth channel; 44—785nm Raman Receiving fiber; 45—808nm Raman receiving fiber; 46—785nm Raman emitting fiber; 47—808nm Raman emitting fiber; 48—pigtail; 49—short-range test point limit baffle.

Note: LIBS is Laser-induced breakdown spectroscopy, laser-induced breakdown spectroscopy; XRF is X-ray fluorescence, X-ray fluorescence spectroscopy.

detailed description

The specific embodiment of the present invention is shown in Fig. 1 .

The whole instrument 1 of the integrated spectrometer for the import and export detection of bulk and valuable goods designed by the present invention mainly includes a main controller 38, a user interactive display screen 40, an integrated multi-channel regulated power supply 41, a LIBS subsystem, a ranging subsystem, a card type telescope, XRF subsystem and BLR subsystem.

Among them, the LIBS subsystem is composed of LIBS signal acquisition mirror 3, pigtail 48, LIBS dichroic mirror 5, LIBS beam expander mirror 6, timing controller 39, LIBS laser 8 and four-channel spectrometer 2; the ranging subsystem consists of ranging laser 9. The range-finding beam expander 11, the half mirror 12 and the range-finding polychromatic mirror 13 are composed; the cassette telescope is composed of the primary mirror 17, the secondary mirror 23 and the secondary mirror driving mechanism 37; the XRF subsystem consists of the X-ray tube 25, X-ray focusing mirror 26, acquisition channel 32, X-ray detector 34, preamplifier 35 and spectrum analyzer 36; BLR subsystem consists of 808nm Raman laser 18, 785nm Raman laser 19, 785nm Raman probe 21, 808nm Raman probe 22, dual-wavelength Raman mirror 24, Raman lens 33, 785nm Raman receiving fiber 44, 808nm Raman receiving fiber 45, 785nm Raman emitting fiber 46, 808nm Raman emitting fiber 47 and fiber combiner Composed of 14, the BLR subsystem multiplexes the fourth channel 43 of the four-channel spectrometer 2;

The integrated multi-channel regulated power supply 41 contains a rechargeable lithium battery, and has two working modes of AC and DC. In the DC working mode, no external mains power is needed, and the internal lithium battery provides multiple centralized power supplies; in the AC working mode, it can be connected to the mains interface 42, used to charge the internal lithium battery, while the integrated multi-channel regulated power supply 41 provides multiple centralized power supplies;

The multi-channel power supply integrated with the multi-channel stabilized power supply 41 is to provide the main controller 38, the user interactive display screen 40, the LIBS laser 8, the ranging laser 9, the 808nm Raman laser 18, the 785nm Raman laser 19 and the X-ray tube 25 working voltage;

There is main control software in the main controller 38, which is used to interact with the user display screen 40, timing controller 39, ranging laser 9, 808nm Raman laser 18, 785nm Raman laser 19, X-ray tube 25 and secondary mirror drive mechanism 37 for control; through the interface, the four-channel spectrometer 2 is powered and received and analyzed for its output spectrum signal; receiving and analyzing the output data of the ranging sensor 15 and the spectrum analyzer 36; Return the test results such as data and charts required by the user;

Main optical axis 4, LIBS optical axis 7, ranging optical axis 10, ranging optical axis 16, XRF emitting optical axis 27 and XRF receiving optical axis 29 are all located in the same plane; LIBS optical axis 7 and ranging optical axis 10 The two are parallel and perpendicular to the main optical axis 4; the distance measuring secondary optical axis 16 is perpendicular to the distance measuring optical axis 10, that is, parallel to the main optical axis 4; the XRF emission optical axis 27 and XRF receiving optical axis 29 are about the main optical axis 4 symmetrical distribution;

The primary mirror 17 of the cassette telescope is fixed, and the secondary mirror 23 can move along the primary optical axis 4 driven by the secondary mirror driving mechanism 37. The range of movement is a limited distance. At the nearest time, the focal length of the cassette telescope was the longest, and now the laser light emitted by the LIBS laser 8 was focused and converged on the remote test point 30 through the cassette telescope; otherwise, when the secondary mirror 23 moved to the farthest distance from the primary mirror 17, The focal length of the card-type telescope is the shortest. At this time, the laser light emitted by the LIBS laser 8 is focused and converged on the short-range test point 28 through the card-type telescope; the short-range test point 28 to the remote test point 30 is the LIBS test range. The ranging subsystem assists in realizing LIBS self-focusing function; both XRF and BLR are short-range tests, that is, the test point is short-range test point 28, that is, LIBS, XRF, and BLR short-range tests are all at the same target point; short-range tests A short-range test point limit baffle 49 is installed at point 28. When the product test object fits the baffle, the product test object is limited to the short-range test point 28, which meets the requirements of LIBS, XRF, and BLR short-range tests. ;

The complete instrument 1 has a test window 31 at the position facing the main optical axis 4, which allows the emission beams and echo signals of LIBS, XRF and BLR to freely enter and exit the complete instrument 1;

The combined spectrometer for the import and export detection of bulk and valuable goods works in the following steps:

(1) Remote LIBS coarse inspection

The main controller 38 sends a control instruction to start the ranging laser 9 (in this embodiment, a 1550nm continuous semiconductor laser), and the continuous laser light sent by the ranging laser 9 advances along the ranging optical axis 10, and is expanded by the ranging beam expander 11 , through the half-mirror 12, reflected by the ranging polychromatic mirror 13, and then penetrate the central hole 20 of the primary mirror 17 of the cassette telescope along the direction of the main optical axis 4, reflected by the secondary mirror 23, and then reflected and focused by the primary mirror 17 For the far-distance product test object, because the focal length of the cassette telescope does not match the distance of the product, it is in a defocused state at this time. The backscattered echo of the product test object travels in the opposite direction along the main optical axis 4, firstly reflected by the primary mirror 17, then reflected by the secondary mirror 23, passes through the central hole 20, is reflected by the ranging polychromatic mirror 13, and then along the ranging The optical axis 10 advances, and then travels along the ranging secondary optical axis 16 after being reflected by the half mirror 12, and is received by the ranging sensor 15, and the sensing signal of the ranging sensor 15 is sent to the main controller 38 for analysis to obtain the echo strength value. The main controller 38 issues an instruction to start the secondary mirror drive mechanism 37 to drive the secondary mirror 23 to move continuously along the main optical axis 4, to change the focal length of the cassette telescope, and to continuously test the echo intensity value. When the echo intensity reaches a peak value, the main controller 38 Issue an instruction to close the secondary mirror drive mechanism 17, so that the secondary mirror 23 stops moving, and at this time the state of precise focus is reached;

Under the precise focusing state, the master controller 38 sets the delay time d of the timing controller 39 (d is set as 10 microseconds in this embodiment), and the LIBS laser 8 is first started by the timing controller 39 (1064nm nanoseconds in this embodiment). Second-level pulse laser, repetition frequency 1Hz, single pulse energy 100mJ), and after a delay d, start the four-channel spectrometer 2 to expose and receive the echo signal of LIBS; its working process is:

The pulsed laser light emitted by the LIBS laser 8 travels along the LIBS optical axis 7, expands the beam through the LIBS beam expander 6, and then travels along the main optical axis 4 after being reflected by the LIBS dichroic mirror 5, and penetrates into the card after passing through the distance measuring polychromatic mirror 13. The central hole 20 of the primary mirror 17 of the type telescope is reflected by the secondary mirror 23, and then reflected by the primary mirror 17 and focused to the long-distance cargo test object. The LIBS signal generated by the cargo test object is excited and travels in the opposite direction along the main optical axis 4 , first reflected by the primary mirror 17, then reflected by the secondary mirror 23, passing through the central hole 20, passing through the ranging polychromatic mirror 13 and collected by the LIBS signal collecting mirror 3, and entering the four-channel spectrometer 2 through the pigtail 48 (this implementation For example, in the range of 190-1100nm, it is divided into four channels: 190-350nm, 350-550nm, 550-750nm, and 750-1100nm, of which the fourth channel 43 is the LIBS and BLR spectral multiplexing channel), after grating splitting and photoelectric conversion The spectral data sent to the master controller 38 for storage and analysis;

The LIBS substance analysis software program of the main controller 38 analyzes the collected remote LIBS spectral data to obtain the material element composition of the goods test object and the rough inspection value of the content. If it is considered to be no problem, the goods can be released; otherwise, if If the judgment is suspicious, enter the next step of short-range precision measurement;

(2) Short-range comprehensive spectrum precision measurement

Move the combined spectrometer for the import and export detection of bulk and valuable goods closer to the goods test object, so that the goods test object fits the short-range test point limit baffle 49, and the main controller 38 issues an instruction to start the secondary mirror drive mechanism 37 to drive the secondary mirror 23 along the The main optical axis 4 moves to the farthest position between the primary mirror 17 and the secondary mirror 23. At this time, the focal length of the clip-on telescope is the shortest, and the laser emitted by the LIBS laser 8 will be focused on the short-range test point 28 through the clip-on telescope;

The main controller 38 sends an instruction and the timing controller 39 first starts the LIBS laser 8, and then after a delay d, starts the four-channel spectrometer 2 to expose and receive the echo signal of the LIBS;

The LIBS material analysis software program of the main controller 38 analyzes the collected short-range LIBS spectral data, and obtains the elemental composition of the goods test object including light, heavy elements, non-metallic elements, and metallic elements, as well as the content values of each element ;

The main controller 38 issues an instruction to start the X-ray tube 25. The X-rays emitted by the X-ray tube 25 travel along the XRF emission optical axis 27, and are focused to the short-range test point 28 by the X-ray focusing mirror 26. The X-ray fluorescence signal generated by the goods test object Traveling along the XRF receiving optical axis 29, after passing through the acquisition channel 32, it is received by the X-ray detector 34, then amplified by the preamplifier 35, and then enters the spectrum analyzer 36 for analysis, and the XRF spectrum data is sent to the main controller 38 for storage and analysis;

The XRF material analysis software program of the main controller 38 analyzes the collected short-range XRF spectral data, obtains the composition and precise content of the heavy elements of the goods test object, and synthesizes the element composition and content results with the LIBS short-range detection results , to obtain the composition and content of light and heavy elements, to measure the composition and content of bulk goods and valuable goods, to carry out anti-counterfeiting detection and to establish a corresponding database;

The main controller 38 sends an instruction to start the 785nm Raman laser 19, and the 785nm continuous laser light emitted by the 785nm Raman laser 19 enters the 785nm Raman probe 21 through the 785nm Raman emission fiber 46, and forms a narrow line through the 785nm interference filter inside it. The wide laser beam is emitted, reflected by the dual-wavelength Raman reflector 24, and travels along the main optical axis 4, and converges to the short-range test point 28 through the Raman lens 33, and the backward Raman scattering signal generated by the goods test object is reflected along the main optical axis 4. Go forward, enter the 785nm Raman probe 21 after passing through the Raman lens 33, enter the 785nm Raman receiving fiber 44 after passing through the 785nm Rayleigh filter inside it, and then enter the four-channel spectrometer 2 after passing through the fiber combiner 14 The 4th channel 43 of the 785nm Raman spectrum data after grating splitting, photoelectric conversion is sent to the main controller 38 for storage and analysis;

The main controller 38 sends an instruction to start the 808nm Raman laser 18, and the 808nm continuous laser light emitted by the 808nm Raman laser 18 enters the 808nm Raman probe 22 through the 808nm Raman emitting fiber 47, and forms a narrow line through the 808nm interference filter inside it. The wide laser beam is emitted, reflected by the dual-wavelength Raman reflector 24, and travels along the main optical axis 4, and converges to the short-range test point 28 through the Raman lens 33, and the backward Raman scattering signal generated by the goods test object is reflected along the main optical axis 4. Go forward, enter the 808nm Raman probe 22 after passing through the Raman lens 33, enter the 808nm Raman receiving fiber 45 after passing through the 808nm Rayleigh filter inside it, and then enter the four-channel spectrometer 2 after passing through the fiber combiner 14 The 4th channel 43 of the 808nm Raman spectrum data after grating splitting, photoelectric conversion is sent to the main controller 38 for storage and analysis;

The BLR substance analysis software program of the main controller 38 analyzes the collected short-range 785nm and 808nm Raman spectral data, removes the fluorescence interference through the differential method, and obtains the product test object’s specificity according to the dual-wavelength Raman frequency shift and intensity. Macromolecular composition and content can be analyzed for toxic and harmful substances.

Claims (1)

1. A combined spectrum detection method for bulk and valuable goods import and export detection, the method is realized on a combined spectrum detector, and the instrument complete machine (1) of the combined spectrum detector includes a main controller ( 38), user interactive display screen (40), integrated multi-channel regulated power supply (41), LIBS subsystem, ranging subsystem, cassette telescope, XRF subsystem and BLR subsystem; it is characterized in that the joint spectrum method includes the following step: 1) Remote LIBS rough check The main controller issues a control command to start the ranging laser, and the continuous laser light emitted by the ranging laser travels along the ranging optical axis, expands the beam through the ranging beam expander, passes through the half mirror, is reflected by the ranging polychromatic mirror, and then follows the main beam. The axial direction penetrates into the center hole of the primary mirror of the clip-on telescope, is reflected by the secondary mirror, and then reflected by the primary mirror and focused on the long-distance cargo test object. Since the focal length of the cassette telescope does not match the distance of the cargo, it is Defocus state. The backscattered echo of the goods test object travels in the opposite direction along the main optical axis. It is first reflected by the primary mirror, then reflected by the secondary mirror, passes through the center hole, and travels along the distance measuring optical axis after being reflected by the distance measuring polychromatic mirror. After being reflected by the half mirror, it travels along the secondary optical axis of distance measurement, and is received by the distance measurement sensor. The sensing signal of the distance measurement sensor is sent to the main controller for analysis, and the echo intensity value is obtained; the main controller issues an instruction to start the secondary mirror The driving mechanism drives the secondary mirror to move continuously along the main optical axis, changes the focal length of the cassette telescope, and continuously tests the echo intensity value. When the echo intensity reaches the peak value, the main controller sends an instruction to turn off the secondary mirror driving mechanism to stop the secondary mirror from moving. , at this time the precise focus state is reached; In the state of precise focusing, the main controller sets the delay time d of the timing controller, and the timing controller first starts the LIBS laser, and then starts the four-channel spectrometer to expose and receive the echo signal of LIBS after the delay d; its working process for: The pulsed laser emitted by the LIBS laser travels along the LIBS optical axis, expands the beam through the LIBS beam expander, and then travels along the main optical axis after being reflected by the LIBS dichroic mirror. The central hole is reflected by the secondary mirror, and then reflected by the primary mirror and focused to the long-distance cargo test object. The LIBS signal generated by the cargo test object travels in the opposite direction along the main optical axis, first reflected by the primary mirror, and then passed by the secondary mirror. Reflected, passed through the central hole, passed through the distance measuring polychromatic mirror, collected by the LIBS signal acquisition mirror, entered the four-channel spectrometer through the pigtail, passed through the grating, and the photoelectrically converted spectral data was sent to the main controller for storage and analysis; The LIBS material analysis software program of the main controller analyzes the collected remote LIBS spectral data, and obtains the material element composition of the test object of the goods and the rough inspection value of the content. If it is considered to be no problem, the goods can be released; otherwise, if it is judged If it is suspicious, enter the next step of short-range precise measurement; 2) Short-range comprehensive spectrum precision measurement Move the combined spectrometer for import and export detection of bulk and valuable goods closer to the goods test object, so that the goods test object fits the limit baffle of the short-range test point, and the main controller sends an instruction to start the secondary mirror driving mechanism to drive the secondary mirror to move along the main optical axis To the position where the distance between the primary mirror and the secondary mirror is the farthest, at this time, the focal length of the clip-on telescope is the shortest, and the laser emitted by the LIBS laser will be focused on the short-range test point through the clip-on telescope; The main controller sends an instruction, and the timing controller first starts the LIBS laser, and then after a delay d, starts the four-channel spectrometer to expose and receive the echo signal of LIBS; The LIBS material analysis software program of the main controller analyzes the collected short-range LIBS spectral data, and obtains the element composition of the goods test object, including light, heavy elements, non-metallic elements, and metal elements, as well as the content value of each element; The main controller sends an instruction to start the X-ray tube. The X-rays emitted by the X-ray tube travel along the XRF emission optical axis, and are focused to the short-range test point by the X-ray focusing mirror. The X-ray fluorescence signal generated by the goods test object travels along the XRF reception optical axis. , after being received by the X-ray detector through the acquisition channel, and then amplified by the preamplifier, it enters the spectrum analyzer for analysis, and the XRF spectrum data is sent to the main controller for storage and analysis; The XRF material analysis software program of the main controller analyzes the collected short-range XRF spectral data, obtains the composition and precise content of the heavy elements of the goods test object, and integrates the element composition and content results with the LIBS short-range detection results, Obtain the composition and content of light and heavy elements, measure the composition and content of bulk goods and valuable goods, carry out anti-counterfeiting detection and establish a corresponding database; The main controller issues an instruction to start the 785nm Raman laser. The 785nm continuous laser emitted by the 785nm Raman laser enters the 785nm Raman probe through the 785nm Raman emitting fiber, and passes through its internal 785nm interference filter to form a narrow linewidth laser. After being reflected by the dual-wavelength Raman mirror, it travels along the main optical axis and converges to the short-range test point through the Raman lens. The 785nm Raman probe enters the 785nm Raman receiving fiber after passing through its internal 785nm Rayleigh filter, and then enters the fourth channel of the four-channel spectrometer after passing through the fiber combiner. The Mann spectral data is sent to the main controller for storage and analysis; The main controller sends an instruction to start the 808nm Raman laser, and the 808nm continuous laser emitted by the 808nm Raman laser enters the 808nm Raman probe through the 808nm Raman emitting fiber, and passes through its internal 808nm interference filter to form a narrow linewidth laser. After being reflected by the dual-wavelength Raman mirror, it travels along the main optical axis and converges to the short-range test point through the Raman lens. The 808nm Raman probe enters the 808nm Raman receiving fiber after passing through its internal 808nm Rayleigh filter, and then enters the fourth channel of the four-channel spectrometer after passing through the fiber combiner. The Mann spectral data is sent to the main controller for storage and analysis; The BLR material analysis software program of the main controller analyzes the collected short-range 785nm and 808nm Raman spectral data, removes the fluorescence interference through the differential method, and obtains the high Molecular composition and content can be analyzed for toxic and harmful substances.