CN211318203U - Portable LIBS composition analyzer - Google Patents

Abstract

The utility model relates to a portable LIBS composition analyzer; the analyzer comprises a main case and a handheld collecting head which are connected together through a cable, wherein a control circuit and a control module of a laser are arranged in the case of the main case, and a laser head, a focusing lens, an optical collector, a spectrometer, a movable platform, a sliding rail, a fine adjustment device and three laser displacement sensors of the laser are arranged in a shell of the handheld collecting head; the laser displacement sensor is positioned around the emitting opening of the laser head, the focusing lens is positioned in front of the emitting opening of the laser head, the light collector is positioned at one side of the laser head, and the middle part of the front end surface of the casing is provided with a detection window; the utility model overcomes cause the defect that the detection condition changes because of factors such as operator's hand trembles among the prior art, reduced detection error.

Description

Portable LIBS composition analyzer

The technical field is as follows:

the utility model relates to a LIBS composition analysis appearance, in particular to portable LIBS composition analysis appearance.

(II) background art:

the Laser Induced Breakdown Spectroscopy (LIBS) technique is an atomic emission Spectroscopy technique in which a sample is ablated by high-intensity pulsed Laser to excite plasma, and the collected plasma optical signals are analyzed by a spectrometer to obtain the types and contents of elements contained in the sample. The LIBS technology has great application potential in the fields of metallurgy, environmental monitoring, deep sea exploration, cultural relic identification, space exploration, energy development and the like.

The LIBS technology is very convenient for processing samples, can be used in laboratories as a new material identification and quantitative analysis technology, can also be used in industrial fields or on-line detection, and does not need to sample the samples to the laboratories for long-time preparation and analysis, so that the analysis technology is greatly expanded from the laboratory field to the outdoor, field and even production process. While a portable LIBS composition analyzer can achieve this advantage very well.

However, the portable LIBS component analyzer adopts a handheld collecting head to collect data, the hand shakes due to physiological factors such as respiration and heartbeat of a person, the surfaces of many samples are not standard planes, the situation is complex, the shaking cannot be completely avoided even if the front end surface of the collecting head is abutted against the surfaces of the samples for detection, the shaking can cause the distance between a lens and the samples and the change of the analysis conditions of the angles of light beams and the surfaces of the samples, the consistency of the detection and analysis conditions of the same sample for multiple times is difficult to ensure, the quality of collected data can be reduced, the analysis error can be caused, the analysis performance of the analyzer can be reduced, and the application and the full display of the detection capability of the LIBS in-site and field occasions can be limited.

(III) content of the utility model:

the to-be-solved technical problem of the utility model is: the portable LIBS component analyzer overcomes the defect that detection conditions change due to factors such as hand shaking of an operator in the working process of the conventional portable LIBS component analyzer, reduces detection errors and has better performance.

The technical scheme of the utility model:

a portable LIBS composition analyzer comprises a main case and a handheld collecting head, wherein the main case comprises a case body, a control circuit and a control module of a laser are arranged in the case body, the handheld collecting head comprises a machine shell, a laser head, a focusing lens, an optical collector, a spectrometer, a movable platform, a sliding rail, an up-down fine adjustment device, a left-right fine adjustment device, a front-back fine adjustment device and three same laser displacement sensors are arranged in the machine shell, and the handheld collecting head is connected with the main case through a communication cable; the laser for LIBS component analysis is emitted from an emitting port at the front end of a laser head, a horizontally arranged slide rail is fixedly arranged on the inner lower wall of a machine shell, the bottom of a movable platform is connected with the slide rail in a sliding way, the movable platform moves back and forth on the slide rail through the bottom of the movable platform, the laser head is fixedly arranged on the upper surface of the movable platform, two ends of an upper fine adjustment device and a lower fine adjustment device are respectively and fixedly connected with the inner upper wall of the machine shell and the upper side surface of the laser head through universal joints, two ends of a left fine adjustment device and a right fine adjustment device are respectively and fixedly connected with the inner left wall of the machine shell and the left side surface of the laser head through universal joints or two ends of the left fine adjustment device and the right fine adjustment device are respectively and fixedly connected with the inner front wall of the machine shell and the front side surface at the bottom of the movable platform or two ends of the front fine adjustment device and the rear, the laser displacement sensors are fixedly arranged in front of the laser head through a support, the support is fixedly connected with the upper surface of the movable platform, the three laser displacement sensors are positioned around the emission port of the laser head and are uniformly distributed around the central axis of the emission port of the laser head, and the emission ports of the three laser displacement sensors are arranged forwards; the upper fine adjustment device, the lower fine adjustment device, the left fine adjustment device, the right fine adjustment device and the front fine adjustment device and the rear fine adjustment device are fine adjustment devices with the same structure, each fine adjustment device comprises a cylindrical shell, one end of each cylindrical shell is closed, a through hole is formed in the middle of the end face of the other end of each cylindrical shell, a piezoelectric ceramic block, a stop block and a compression spring with inverse piezoelectric effect are sequentially installed in each cylindrical shell from the closed end of each cylindrical shell, a first connecting rod extends outwards from the closed end of each cylindrical shell, a second connecting rod extends out of the surface, in contact with the compression spring, of each stop block, and sequentially penetrates out of the compression spring and the through holes in the end face of each cylindrical shell, and the end parts of each first connecting rod and; the focusing lens, the light collector and the spectrometer are all arranged on the movable platform, the focusing lens is positioned in front of an emission port of the laser head, a main optical axis of the focusing lens is superposed with the central axis of the emission port of the laser head, the light collector is positioned at one side of the laser head, a receiving port of the light collector faces towards the inner front, laser emitted from the emission port of the laser head is converged at or near the objective lens focus of the receiving port of the light collector after passing through the focusing lens, the main optical axis of the focusing lens passes through the objective lens focus of the receiving port of the light collector, and the objective lens focus of the receiving port of the light collector is positioned on a plane where the front end face of the shell is positioned; the front end face of the machine shell is a plane perpendicular to the central axis of the emitting port of the laser head, the middle part of the front end face of the machine shell is provided with a detection window, lasers emitted by the laser head and the three laser displacement sensors are all emitted out of the detection window, light received by the receiving port of the light collector enters from the detection window, the front end face of the machine shell is provided with a laser protection switch, when the laser protection switch is pressed down, the surface of the laser protection switch and the front end face of the machine shell are positioned on the same plane, and the outer side face of the machine shell is provided with a laser light-emitting indicator; a handle is arranged on the outer bottom surface of the shell, and a trigger switch is arranged on the handle; the laser protection switch and the trigger switch are connected in series and then connected to a light-out/light-off control signal interface of the control module through a communication cable, a light-out indicator lamp of the laser is connected with a signal output end of an indicator lamp of the control module through the communication cable, a trigger signal output end of the control module is connected with an external trigger signal input end of the spectrometer through the communication cable so as to control the signal acquisition time sequence of the spectrometer, an output optical fiber interface of the light collector is connected with an input optical fiber interface of the spectrometer, a detection signal output port of the spectrometer is connected with a spectrum detection signal input port of the control circuit through the communication cable, three laser displacement sensors are connected with a position signal input port of the control circuit through the communication cable, an upper fine adjustment device, a lower fine adjustment device, a left fine adjustment device, a right fine adjustment device and a piezoelectric ceramic block in, the power input end of the control module is connected with the power output end of the control circuit, and the laser output control port of the control module is connected with the laser head through a communication cable; the laser protection switch and the trigger switch are both lock-free button switches, and the laser light-emitting indicator lamp is an LED lamp.

The three laser displacement sensors detect the distance from a focusing lens to a sample and the angle of a laser axis relative to the surface of the sample by measuring the distance between the three laser displacement sensors and the surface of the sample, signals detected by the three laser displacement sensors are input into the control circuit, the control circuit judges the up-down, left-right and front-back postures of the laser head according to the received signals, if the postures of the laser head are found to be improper, a position adjusting signal is sent out, and the position adjusting signal controls the thicknesses of the piezoelectric ceramic blocks in the up-down fine adjusting device, the left-right fine adjusting device and the front-back fine adjusting device to change, so that the up-down, left-right and front-back postures of the laser head are finely adjusted, and offset generated by the improper postures of the laser head.

When the thickness of the piezoelectric ceramic block is increased, the stop block can be pushed to move towards the compression spring, so that the whole length of the fine adjustment device is increased; when the thickness of the piezoelectric ceramic block is reduced, the compression spring pushes the stop block to move towards the piezoelectric ceramic block, so that the whole length of the fine adjustment device is reduced; the posture of the laser head is adjusted by the three fine-adjustment devices through the length change of the three fine-adjustment devices, so that the laser beams emitted by the laser head are perpendicular to the surface of the sample, and the emitting ports and the surface of the sample keep a fixed distance.

The movable platform comprises a base, a vertical rotating shaft and a platform supporting plate, wherein a sliding groove matched with the sliding rail is formed in the bottom surface of the base, the base is connected with the sliding rail in a sliding mode through the sliding groove, a round hole is formed in the upper surface of the base, the lower end of the vertical rotating shaft is installed in the round hole through a bearing, the upper end of the vertical rotating shaft is hinged to the middle of the lower surface of the platform supporting plate through a hinge shaft, the hinge shaft is horizontally arranged along the left-right direction, and the platform supporting plate; two ends of the front and rear fine tuning devices are respectively fixedly connected with the inner front wall of the machine shell and the front side surface of the movable platform base or two ends of the front and rear fine tuning devices are respectively fixedly connected with the inner rear wall of the machine shell and the rear side surface of the movable platform base; the laser head and the support are fixedly arranged on the upper surface of the platform supporting plate, and the joints of the laser head, the upper fine adjustment device, the lower fine adjustment device and the left fine adjustment device and the right fine adjustment device are positioned at the front part of the movable platform. A diaphragm is arranged between the laser head emission opening and the focusing lens, and the central axis of the diaphragm is superposed with the central axis of the laser head emission opening. The diaphragm can reshape the laser emitted from the emitting opening of the laser head.

The sliding groove is a dovetail groove, and the sliding rail is a dovetail-shaped sliding rail matched with the sliding groove; the focusing lens is arranged on the upper surface of the platform supporting plate through the lens bracket; the diaphragm is arranged on the upper surface of the platform supporting plate through the diaphragm bracket; the light collector is arranged on the lower surface of the platform supporting plate through a light collector bracket and is positioned on one side in front of the laser head emission port; the spectrometer is directly arranged on the lower surface of the platform supporting plate; the handle is of a combined hollow structure, the handle comprises a left half part and a right half part, and a connecting lead on the trigger switch sequentially penetrates through a vertical through hole on the bottom surface of the machine shell and a transverse groove on the bottom surface of the slide rail from the inside of the handle, enters the machine shell and is connected with the laser protection switch; the machine shell is of a combined structure and comprises a left shell and a right shell, and the sliding rail, the up-down fine adjustment device, the left-right fine adjustment device and the front-back fine adjustment device are all fixed on the inner wall of the right shell; the outside of trigger switch has surrounded the trigger protective shroud, and the one end of trigger protective shroud is connected on the leading flank of handle, and the other end of trigger protective shroud is connected on the outer bottom surface of casing, and the trigger protective shroud can prevent that trigger switch from being touched by the mistake.

The support contains the ring of fixing in laser head the place ahead, and the central axis of ring coincides with the central axis of laser head transmission mouth, and the upper surface fixed connection of bracing piece and platform backup pad is passed through to the lower part of ring, and the periphery of ring outwards evenly stretches out three the same installation pole, and three laser displacement sensor installs respectively on three installation pole, and the center of three laser displacement sensor is located same perpendicular to laser head transmission mouth the plane of central axis.

The central axes of the three laser displacement sensor emitting ports intersect at one point on the central axis of the laser head emitting port, the included angles between the central axes of the three laser displacement sensor emitting ports and the central axis of the laser head emitting port are both alpha, and alpha is less than 25 degrees.

The three laser displacement sensors are respectively arranged on the side surfaces of the three mounting rods through three fastening bolts, and the size of the included angle alpha is adjusted through the fastening bolts.

The laser head is a column, the laser head is transversely fixedly installed on the upper surface of the platform supporting plate through a fastening hoop on the laser head, the fastening hoop is located in the front of the platform supporting plate, the upper fine adjustment device and the lower fine adjustment device are fixedly connected with the upper side surface of the laser head through the fastening hoop, and the left fine adjustment device and the right fine adjustment device are also fixedly connected with the left side surface or the right side surface of the laser head through the fastening hoop.

The control circuit comprises a microcomputer, a battery pack, a starting button, three signal converters, three piezoelectric controllers, a piezoelectric control USB concentrator and a power supply, signal output ports of three laser displacement sensors are respectively connected with position signal input ports of the microcomputer through the three signal converters, a position adjusting signal output port of the microcomputer is connected with input ports of the piezoelectric control USB concentrator and the power supply, three output ports of the piezoelectric control USB concentrator and the power supply are respectively connected with upper and lower fine tuning devices, left and right fine tuning devices and piezoelectric ceramic blocks in the front and rear fine tuning devices through the three piezoelectric controllers, a detection signal output port of a spectrometer is connected with a spectrum detection signal input port of the microcomputer, a control signal input port of a control module of the laser is connected with a laser control signal output port of the microcomputer, and the battery pack gives the microcomputer, a control module of the laser, three laser displacement sensors and the piezoelectric control USB concentrator through the starting button Controlling the USB concentrator and the power supply, and taking electricity from the microcomputer by the spectrometer through a power supply end on a detection signal output port (such as a USB port); the laser is a miniature laser, and the spectrometer is a miniature spectrometer.

The laser instrument comprises control module and laser head, and the model of laser instrument is: DPS-1064-mini type nanosecond pulse laser in new Changchun industry; the laser displacement sensor has the following types: under pine HL-G108-S-J; the types of the piezoelectric ceramic blocks are as follows: PC4QR form of thralabs; the types of the piezoelectric controller are as follows: type KPZ101 of Throlabs; the piezoelectric control USB concentrator and the power supply are of the following types: (ii) the KCH301 form of thralabs; the universal joint is a spherical universal joint; the spectrometer has the following model: Avaspec-Mini2048-UVI 10; the front part of the shell is in a frustum shape; the signal converter is a USB-RS-422/485 converter, the signal output port of the laser displacement sensor is an RS-422 interface or an RS-485 interface, and the position signal input port of the microcomputer is a USB interface.

The box body comprises an upper cover and a lower box body, a display of a microcomputer is mounted on the inner top surface of the upper cover, a host of the microcomputer, a battery pack, a control module of a laser, three piezoelectric controllers, a piezoelectric control USB concentrator and a power supply are mounted in an interlayer on the bottom surface of the lower box body, a starting button is mounted on the upper portion of the inner side surface of the lower box body, a connecting cable between the upper cover and the lower box body penetrates out of the upper cover and then enters the interlayer on the bottom surface of the lower box body from the inner side wall of the lower box body, and a communication cable between the host box and a handheld collecting head penetrates out of the inner bottom surface of the lower box body and then enters the casing from a threading hole in the rear portion of the casing.

The use method of the portable LIBS component analyzer is as follows: the method comprises the steps that firstly, an upper cover of a mainframe box is opened, a starting button is pressed down, a battery pack supplies power to a microcomputer, a control module of a laser, three laser displacement sensors, a piezoelectric control USB concentrator and a power supply, the microcomputer and the laser are in a starting state, the microcomputer supplies power to a spectrometer through a USB data line, and the spectrometer is started. When LIBS analysis is needed, firstly, analysis parameters are set on the microcomputer, then a handle of the handheld collecting head is held by a hand, the front end face of the handheld collecting head is enabled to abut against the surface of a sample (at the moment, the laser protection switch is turned on), detection can be carried out by pulling the trigger switch, a detection analysis result is displayed on a display of the microcomputer, and after the detection is finished, the trigger switch is released, and the handheld collecting head is moved away from the surface of the sample.

Because the laser protection switch and the trigger switch are connected in series, the laser head can emit light only when the laser protection switch and the trigger switch are simultaneously turned on; the laser protection switch is opened only when the front end face of the handheld collecting head abuts against the surface of a sample, and the front end face of the handheld collecting head is disconnected when being separated from the surface of the sample, so that light emitting of the laser head is interrupted, and the risk of laser leakage is avoided.

The laser emits light, and the spectrometer is controlled by the trigger signal line to collect spectrum in reasonable time, and the spectrometer transmits collected spectrum data back to the microcomputer through the data line, and stores and analyzes the data on the microcomputer.

When the LIBS composition analyzer is not used, the handheld collecting head can be placed in the lower box body to be fixed, and then the upper cover is covered on the lower box body. The inner bottom surface of the lower box body can be provided with a pit matched with the handheld collecting head in shape, the handheld collecting head is clamped in the pit, and the starting button can also be arranged on the inner bottom surface of the lower box body.

The utility model has the advantages that:

1, the utility model adopts three laser displacement sensors to detect the distance from the emitting port of the laser head of the laser to the surface of the sample and the angle relative to the surface of the sample, then controls the actions of the upper and lower fine adjustment devices, the left and right fine adjustment devices, the front and back fine adjustment devices through the detected information, and timely adjusts the posture of the laser head, so that the emitting port of the laser head always keeps the fixed distance to the sample, and the emitted laser is vertical to the surface of the sample; the utility model overcomes the defect that the detection condition that arouses is trembled because of the operator hand in the portable LIBS composition analysis appearance working process changes, has reduced composition analysis appearance's error, makes composition analysis appearance's performance better.

2, the utility model discloses an adopted among the micromatic setting the piezoceramics piece that has inverse piezoelectric effect, when voltage on the piezoceramics piece changes, its thickness can take place small change to make micromatic setting's length take place small change, reach the purpose of fine setting laser head gesture, piezoceramics piece makes micromatic setting's adjustment precision height, adjustment speed piece, is applicable to very much that the adjustment is because the laser head gesture that the hand trembled and arouses changes.

3, the hand-held collecting head of the utility model adopts a miniature laser and a miniature spectrometer, so that the volume of the hand-held collecting head is small and the use is flexible; the handheld collecting head can be placed in the box body of the mainframe box when not in use, and is convenient to carry; the microcomputer is a tablet personal computer, the tablet personal computer is installed in the upper cover of the mainframe box, when the tablet personal computer is detected, parameters can be set on the touch screen of the tablet personal computer and the result of detection and analysis can be observed by opening the upper cover of the box body, and the tablet personal computer is very convenient to use.

(IV) description of the drawings:

FIG. 1 is a schematic diagram of a portable LIBS composition analyzer;

FIG. 2 is a right side enlarged schematic view of the handheld pick head of FIG. 1;

FIG. 3 is a left side view of the structure of FIG. 2 (with the left housing of the housing and the left half of the handle removed);

FIG. 4 is a schematic sectional view A-A of FIG. 3;

FIG. 5 is a schematic view of the structure of FIG. 2 with the frustoconical front portion of the housing removed;

fig. 6 is a schematic circuit diagram of the control circuit.

(V) detailed embodiment:

referring to fig. 1 to 6, in the drawings, the portable LIBS composition analyzer includes a main chassis and a handheld pick-up head, the main chassis includes a chassis body, a control circuit and a control module of a laser are disposed in the chassis body, the handheld pick-up head includes a casing 1, a laser head 2, a focusing lens 39, an optical pick-up 40, a spectrometer 42, a movable platform, a slide rail 4, an up-down fine adjustment device 5, a left-right fine adjustment device 6, a front-back fine adjustment device 7 and three same laser displacement sensors 8 of the laser are disposed in the casing 1, and the handheld pick-up head and the main chassis are connected through a communication cable 50; laser for LIBS composition analysis is emitted from an emitting port 3 at the front end of a laser head 2, a slide rail 4 which is horizontally arranged is fixedly arranged on the inner lower wall of a machine shell 1, the bottom of a movable platform is connected with the slide rail 4 in a sliding way, the movable platform moves back and forth on the slide rail 4 through the bottom of the movable platform, the laser head 2 is fixedly arranged on the upper surface of the movable platform, two ends of an upper fine adjustment device 5 and a lower fine adjustment device 5 are respectively and fixedly connected with the inner upper wall of the machine shell 1 and the upper side surface of the laser head 2 through universal joints 9, two ends of a left fine adjustment device 6 and a right fine adjustment device 6 are respectively and fixedly connected with the inner left wall of the machine shell 1 and the left side surface of the laser head 2 through universal joints 9, two ends of the front fine adjustment device 7 and the rear fine adjustment device 7 are respectively and fixedly connected with the inner rear wall of the machine shell 1 and the rear side surface of the bottom of the, the support 10 is fixedly connected with the upper surface of the movable platform, the three laser displacement sensors 8 are positioned around the emitting port 3 of the laser head 2 and are uniformly distributed around the central axis of the emitting port 3 of the laser head 2, and the emitting ports 33 of the three laser displacement sensors 8 are all arranged forwards; the upper fine adjustment device 5, the lower fine adjustment device 6, the left fine adjustment device 6, the right fine adjustment device 7 and the front fine adjustment device 7 are fine adjustment devices with the same structure, each fine adjustment device comprises a cylindrical shell 11, one end of each cylindrical shell 11 is closed, the middle part of the end face of the other end is provided with a through hole 12, a piezoelectric ceramic block 13, a stop block 14 and a compression spring 15 which have inverse piezoelectric effect are sequentially installed in each cylindrical shell 11 from the closed end of each cylindrical shell 11, a first connecting rod 16 extends out of the closed end of each cylindrical shell 11, a second connecting rod 17 extends out of the surface, in contact with the compression spring 15, of each stop block 14, the second connecting rod 17 sequentially penetrates out of the compression spring 15 and the through holes 12 in the end face of each cylindrical shell 11, and the end parts of the first connecting rod 16 and the second connecting rod 17; the focusing lens 39, the light collector 40 and the spectrometer 42 are all installed on the movable platform, the focusing lens 39 is located in front of the emission port 3 of the laser head 2, the main optical axis of the focusing lens 39 is coincident with the central axis of the emission port 3 of the laser head 2, the light collector 40 is located on one side of the laser head 2, the receiving port of the light collector 40 faces towards the inner front, laser emitted from the emission port 3 of the laser head 2 passes through the focusing lens 39 and then converges at a position 2 mm in front of the objective lens focal point of the receiving port of the light collector 40, the main optical axis of the focusing lens 39 passes through the objective lens focal point of the receiving port of the light collector 40, and the objective lens focal point of the receiving port of the light collector 40 is located on the plane where the front end face 51 of the machine shell 1 is located; the front end face 51 of the machine shell 1 is a plane vertical to the central axis of the emitting port 3 of the laser head 2, the middle part of the front end face 51 of the machine shell 1 is provided with a detection window 52, the laser emitted by the laser head 2 and the three laser displacement sensors 8 is emitted from the detection window 52, the light received by the receiving port of the light collector 40 enters from the detection window 52, the front end face 51 of the machine shell 1 is provided with a laser protection switch 38, when the laser protection switch 38 is pressed down, the surface of the laser protection switch and the front end face 51 of the machine shell 1 are positioned on the same plane, and the outer side face of the machine shell 1 is provided with a laser light-emitting indicator; a handle 35 is arranged on the outer bottom surface of the machine shell 1, and a trigger switch 36 is arranged on the handle 35; the laser protection switch 38 and the trigger switch 36 are connected in series and then connected to an output/off light control signal interface of the control module through a communication cable 50, the laser light-emitting indicator lamp 37 is connected with an indicator lamp signal output end of the control module through the communication cable 50, a trigger signal output end of the control module is connected with an external trigger signal input end of the spectrometer 42 through the communication cable 50 to control a signal acquisition timing sequence of the spectrometer 42, an output optical fiber interface of the light collector 40 is connected with an input optical fiber interface of the spectrometer 42, a detection signal output port of the spectrometer 42 is connected with a spectrum detection signal input port of the control circuit through the communication cable 50, the three laser displacement sensors 8 are connected with a position signal input port of the control circuit through the communication cable 50, the upper and lower fine adjustment device 5, the left and right fine adjustment device 6 and the piezoelectric ceramic blocks 13 in the front and rear fine adjustment device 7 are connected with an output port of the control circuit, the power input end of the control module is connected with the power output end of the control circuit, and the laser output control port of the control module is connected with the laser head 2 through a communication cable 50; the laser protection switch 38 and the trigger switch 36 are both non-lock button switches, and the laser light-emitting indicator lamp 37 is an LED lamp.

The three laser displacement sensors 8 detect the distance from the focusing lens 39 to the sample and the angle of the laser axis relative to the sample surface by measuring the distance between the three laser displacement sensors 8 and the sample surface, signals detected by the three laser displacement sensors 8 are input into the control circuit, the control circuit judges the upper, lower, left, right and front and back postures of the laser head 2 according to the received signals, if the posture of the laser head 2 is found to be improper, a position adjusting signal is sent out, and the position adjusting signal controls the thickness of the piezoelectric ceramic blocks 13 in the upper and lower fine adjusting device 5, the left and right fine adjusting device 6 and the front and back fine adjusting device 7 to change the upper, lower, left, right and front and back postures of the laser head 2, so that offset caused by the improper posture of the laser head 2 due to hand trembling is.

When the thickness of the piezoelectric ceramic block 13 is increased, the stop 14 can be pushed to move towards the compression spring 15, so that the whole length of the fine adjustment device is increased; when the thickness of the piezoelectric ceramic block 13 is reduced, the compression spring 15 pushes the stopper 14 to move towards the piezoelectric ceramic block 13, so that the whole length of the fine adjustment device is reduced; the posture of the laser head 2 is adjusted by the three fine-adjustment devices through the length change of the three fine-adjustment devices, so that the laser beam emitted by the laser head 2 is perpendicular to the surface of the sample, and the emission port 3 is kept at a fixed distance from the surface of the sample.

The movable platform comprises a base 21, a vertical rotating shaft 22 and a platform supporting plate 23, a sliding groove 25 matched with the sliding rail 4 is arranged on the bottom surface of the base 21, the base 21 is connected with the sliding rail 4 in a sliding mode through the sliding groove 25, a round hole 26 is arranged on the upper surface of the base 21, the lower end of the vertical rotating shaft 22 is installed in the round hole 26 through a bearing 27, the vertical rotating shaft 22 can rotate around the axis of the vertical rotating shaft, the upper end of the vertical rotating shaft 22 is hinged to the middle of the lower surface of the platform supporting plate 23 through a hinge shaft 28, the hinge shaft 28 is horizontally arranged in the left-right direction; two ends of the front and rear fine tuning devices 7 are respectively fixedly connected with the inner rear wall of the machine shell 1 and the rear side surface of the movable platform base 21; the laser head 2 and the support 10 are fixedly arranged on the upper surface of the platform supporting plate 23, and the joints of the laser head 2 and the upper and lower fine adjustment devices 5 and the left and right fine adjustment devices 6 are positioned at the front part of the movable platform. A diaphragm 56 is arranged between the laser head 2 emission opening 3 and the focusing lens 39, and the central axis of the diaphragm 56 is superposed with the central axis of the laser head 2 emission opening 3. The diaphragm 56 shapes the laser light emitted from the emitting opening 3 of the laser head 2.

The sliding groove 25 is a dovetail groove, and the sliding rail 4 is a dovetail-shaped sliding rail matched with the sliding groove 25; the focus lens 39 is mounted on the upper surface of the stage support plate 23 through a lens holder 53; a diaphragm 56 is mounted on the upper surface of the platform support plate 23 via a diaphragm holder 57; the light collector 40 is arranged on the lower surface of the platform supporting plate 23 through a light collector bracket 41, and the light collector 40 is positioned on one side in front of the emitting opening 3 of the laser head 2; the spectrometer 42 is mounted directly on the lower surface of the platform support plate 23; the handle 35 is of a combined hollow structure, the handle 35 comprises a left half part and a right half part, and a connecting lead on the trigger switch 36 sequentially penetrates through a vertical through hole 44 on the bottom surface of the machine shell 1 and a transverse groove 45 on the bottom surface of the slide rail 4 from the interior of the handle 35, then enters the interior of the machine shell 1 and is connected with the laser protection switch 38; the machine shell 1 is of a combined structure, the machine shell 1 comprises a left shell and a right shell, and a sliding rail 4, an up-down fine adjustment device 5, a left-right fine adjustment device 5 and a front-back fine adjustment device 7 are all fixed on the inner wall of the right shell; a trigger retainer 55 is provided around the trigger switch 36, one end of the trigger retainer 55 is connected to the front side surface of the handle 35, the other end of the trigger retainer 55 is connected to the outer bottom surface of the housing 1, and the trigger retainer 55 prevents the trigger switch 36 from being erroneously touched.

The support 10 contains the ring 29 of fixing in laser head 2 the place ahead, and the central axis of ring 29 and the coincidence of the central axis of laser head 2 transmission port 3, and the lower part of ring 29 passes through bracing piece 30 and the upper surface fixed connection of platform backup pad 23, and three the same installation pole 31 is outwards evenly stretched out to the periphery of ring 29, and three laser displacement sensor 8 are installed respectively on three installation pole 31, and the center of three laser displacement sensor 8 is located same plane of perpendicular to laser head 2 transmission port 3 central axis.

The central axes of the three emitting ports 33 of the laser displacement sensors 8 are intersected at one point on the central axis of the emitting port 3 of the laser head 2, and the included angles between the central axes of the three emitting ports 33 of the laser displacement sensors 8 and the central axis of the emitting port 3 of the laser head 2 are all alpha, wherein alpha =20.5 degrees.

The three laser displacement sensors 8 are respectively installed on the side surfaces of the three mounting rods 31 through three fastening bolts 34, and the size of the included angle alpha is adjusted through the fastening bolts 34.

The laser head 2 is in a column shape, the laser head 2 is transversely fixedly installed on the upper surface of the platform supporting plate 23 through a fastening hoop 32 on the laser head 2, the fastening hoop 32 is positioned at the front part of the platform supporting plate 23, the upper fine adjustment device 5 and the lower fine adjustment device 5 are fixedly connected with the upper side surface of the laser head 2 through the fastening hoop 32, and the left fine adjustment device 6 and the right fine adjustment device 6 are also fixedly connected with the left side surface of the laser head 2 through the fastening hoop.

The control circuit comprises a microcomputer, a battery pack, a start-up button 49, three signal converters, three piezoelectric controllers, a piezoelectric control USB concentrator and a power supply, signal output ports of three laser displacement sensors 8 are respectively connected with position signal input ports of the microcomputer through the three signal converters, a position adjusting signal output port of the microcomputer is connected with the piezoelectric control USB concentrator and the input port of the power supply, three output ports of the piezoelectric control USB concentrator and the power supply are respectively connected with piezoelectric ceramic blocks 13 in an upper fine adjustment device 5, a lower fine adjustment device 5, a left fine adjustment device 6, a right fine adjustment device 6 and a front fine adjustment device 7 through the three piezoelectric controllers, a detection signal output port of a spectrometer 42 is connected with a spectrum detection signal input port of the microcomputer, a control signal input port of a control module of the laser is connected with a laser control signal output port of the microcomputer, the battery pack supplies power to a microcomputer, a control module of a laser, the three laser displacement sensors 8, a piezoelectric control USB concentrator and a power supply through a starting button 49, and the spectrometer 42 obtains power from the microcomputer through a power supply end on a detection signal output port (such as a USB port) of the spectrometer; the laser is a micro laser and the spectrometer 42 is a micro spectrometer.

The laser instrument comprises control module and laser head 2, and the model of laser instrument is: DPS-1064-mini type nanosecond pulse laser in new Changchun industry; the laser displacement sensor 8 has the following model: under pine HL-G108-S-J; the types of the piezoelectric ceramic blocks 13 are: PC4QR form of thralabs; the types of the piezoelectric controller are as follows: type KPZ101 of Throlabs; the piezoelectric control USB concentrator and the power supply are of the following types: (ii) the KCH301 form of thralabs; the universal joint 9 is a spherical universal joint; the spectrometer 42 is of the type: Avaspec-Mini2048-UVI 10; the front part of the machine shell 1 is in a frustum shape; the signal converter is a USB-RS-422/485 converter, the signal output port of the laser displacement sensor 8 is an RS-422 interface, and the position signal input port of the microcomputer is a USB interface.

The case body comprises an upper cover 47 and a lower case body 46, a display 48 of the microcomputer is installed on the inner top surface of the upper cover 47, a host of the microcomputer, a battery pack, a control module of a laser, three piezoelectric controllers, a piezoelectric control USB concentrator and a power supply are installed in an interlayer on the bottom surface of the lower case body 46, a starting button 49 is installed on the upper portion of the inner side surface of the lower case body 46, a connecting cable 54 between the upper cover 47 and the lower case body 46 penetrates out of the upper cover 47 and then enters the interlayer on the bottom surface of the lower case body 46 from the inner side wall of the lower case body 46, and a communication cable 50 between the host case and a handheld collecting head penetrates out of the inner bottom surface of the lower case body 46 and then enters the case body 1 from a threading hole 43 in the rear portion of the case 1.

The use method of the portable LIBS component analyzer is as follows: first, the upper cover 47 of the mainframe box is opened, the start button 49 is pressed, the battery pack supplies power to the microcomputer, the control module of the laser, the three laser displacement sensors 8, the piezoelectric control USB concentrator and the power supply, the microcomputer and the laser are in a starting state, the microcomputer supplies power to the spectrometer 42 through the USB data line, and the spectrometer 42 is started. When the LIBS analysis is needed, firstly, analysis parameters are set on the microcomputer, then the handle 35 of the handheld collecting head is held by hand, the front end face 51 of the handheld collecting head is enabled to abut against the surface of a sample (at the moment, the laser protection switch 38 is turned on), then the trigger switch 36 is pulled, the detection can be carried out, the detection analysis result is displayed on the display 48 of the microcomputer, and after the detection is finished, the trigger switch 36 is released, and the handheld collecting head is removed from the surface of the sample.

Because the laser protection switch 38 and the trigger switch 36 are connected in series, the laser head 2 can emit light only when the laser protection switch 38 and the trigger switch 36 are simultaneously turned on; the laser protection switch 38 is only opened when the front end face 51 of the handheld pick head abuts against the surface of the sample, and the front end face 51 of the handheld pick head is disconnected when being separated from the surface of the sample, so that light emission of the laser head 2 is interrupted, and no laser leakage risk is guaranteed.

The laser emits light and controls the spectrometer 42 to collect spectra in reasonable time through the trigger signal line, and the spectrometer 42 transmits collected spectral data back to the microcomputer through the data line and stores and analyzes the data on the microcomputer.

When the LIBS analyzer is not used, the hand-held pick head can be placed in the lower case 46 and fixed, and then the upper cover 47 is covered on the lower case 46. A pit matched with the shape of the handheld pick-up head can be arranged on the inner bottom surface of the lower box body 46, the handheld pick-up head is clamped in the pit, and the starting button 49 can also be arranged on the inner bottom surface of the lower box body 46.

Claims (10)

1. A portable LIBS composition analyzer is characterized in that: the handheld collecting head comprises a casing, a laser head, a focusing lens, an optical collector, a spectrometer, a movable platform, a slide rail, an up-down fine adjustment device, a left-right fine adjustment device, a front-back fine adjustment device and three same laser displacement sensors, wherein the casing is internally provided with a box body; the laser for LIBS component analysis is emitted from an emitting port at the front end of a laser head, a horizontally arranged slide rail is fixedly arranged on the inner lower wall of a machine shell, the bottom of a movable platform is connected with the slide rail in a sliding way, the movable platform moves back and forth on the slide rail through the bottom of the movable platform, the laser head is fixedly arranged on the upper surface of the movable platform, two ends of an upper fine adjustment device and a lower fine adjustment device are respectively and fixedly connected with the inner upper wall of the machine shell and the upper side surface of the laser head through universal joints, two ends of a left fine adjustment device and a right fine adjustment device are respectively and fixedly connected with the inner left wall of the machine shell and the left side surface of the laser head through universal joints or two ends of the left fine adjustment device and the right fine adjustment device are respectively and fixedly connected with the inner front wall of the machine shell and the front side surface at the bottom of the movable platform or two ends of the front fine adjustment device and the rear, the laser displacement sensors are fixedly arranged in front of the laser head through a support, the support is fixedly connected with the upper surface of the movable platform, the three laser displacement sensors are positioned around the emission port of the laser head and are uniformly distributed around the central axis of the emission port of the laser head, and the emission ports of the three laser displacement sensors are arranged forwards; the upper fine adjustment device, the lower fine adjustment device, the left fine adjustment device, the right fine adjustment device and the front fine adjustment device and the rear fine adjustment device are fine adjustment devices with the same structure, each fine adjustment device comprises a cylindrical shell, one end of each cylindrical shell is closed, a through hole is formed in the middle of the end face of the other end of each cylindrical shell, a piezoelectric ceramic block, a stop block and a compression spring with inverse piezoelectric effect are sequentially installed in each cylindrical shell from the closed end of each cylindrical shell, a first connecting rod extends outwards from the closed end of each cylindrical shell, a second connecting rod extends out of the surface, in contact with the compression spring, of each stop block, and sequentially penetrates out of the compression spring and the through holes in the end face of each cylindrical shell, and the end parts of each first connecting rod and; the focusing lens, the light collector and the spectrometer are all arranged on the movable platform, the focusing lens is positioned in front of an emission port of the laser head, a main optical axis of the focusing lens is superposed with the central axis of the emission port of the laser head, the light collector is positioned at one side of the laser head, a receiving port of the light collector faces towards the inner front, laser emitted from the emission port of the laser head is converged at or near the objective lens focus of the receiving port of the light collector after passing through the focusing lens, the main optical axis of the focusing lens passes through the objective lens focus of the receiving port of the light collector, and the objective lens focus of the receiving port of the light collector is positioned on a plane where the front end face of the shell is positioned; the front end face of the machine shell is a plane perpendicular to the central axis of the emitting port of the laser head, the middle part of the front end face of the machine shell is provided with a detection window, lasers emitted by the laser head and the three laser displacement sensors are all emitted out of the detection window, light received by the receiving port of the light collector enters from the detection window, the front end face of the machine shell is provided with a laser protection switch, when the laser protection switch is pressed down, the surface of the laser protection switch and the front end face of the machine shell are positioned on the same plane, and the outer side face of the machine shell is provided with a laser light-emitting indicator; a handle is arranged on the outer bottom surface of the shell, and a trigger switch is arranged on the handle; the laser protection switch and the trigger switch are connected in series and then connected to a light-out/light-off control signal interface of the control module through a communication cable, a light-out indicator lamp of a laser is connected with a signal output end of an indicator lamp of the control module through the communication cable, a trigger signal output end of the control module is connected with an external trigger signal input end of a spectrometer through the communication cable, an output optical fiber interface of an optical collector is connected with an input optical fiber interface of the spectrometer, a detection signal output port of the spectrometer is connected with a spectrum detection signal input port of the control circuit through the communication cable, three laser displacement sensors are connected with a position signal input port of the control circuit through the communication cable, an upper fine adjustment device, a lower fine adjustment device, a left fine adjustment device, a right fine adjustment device and a piezoelectric ceramic block in the front fine adjustment device and the rear fine adjustment device are connected with an output port, a laser output control port of the control module is connected with the laser head through a communication cable; the laser protection switch and the trigger switch are both lock-free button switches.

2. The portable LIBS composition analyzer of claim 1, wherein: the movable platform comprises a base, a vertical rotating shaft and a platform supporting plate, wherein a sliding groove matched with the sliding rail is formed in the bottom surface of the base, the base is connected with the sliding rail in a sliding mode through the sliding groove, a round hole is formed in the upper surface of the base, the lower end of the vertical rotating shaft is installed in the round hole through a bearing, the upper end of the vertical rotating shaft is hinged to the middle of the lower surface of the platform supporting plate through a hinge shaft, the hinge shaft is horizontally arranged along the left-right direction, and the platform supporting plate rotates; two ends of the front and rear fine tuning devices are respectively fixedly connected with the inner front wall of the machine shell and the front side surface of the movable platform base or two ends of the front and rear fine tuning devices are respectively fixedly connected with the inner rear wall of the machine shell and the rear side surface of the movable platform base; the laser head and the bracket are fixedly arranged on the upper surface of the platform supporting plate, and the connecting parts of the laser head, the upper fine adjustment device, the lower fine adjustment device and the left fine adjustment device and the right fine adjustment device are positioned at the front part of the movable platform; a diaphragm is arranged between the laser head emission opening and the focusing lens, and the central axis of the diaphragm is superposed with the central axis of the laser head emission opening.

3. The portable LIBS composition analyzer of claim 2, wherein: the sliding groove is a dovetail groove, and the sliding rail is a dovetail-shaped sliding rail matched with the sliding groove; the focusing lens is arranged on the upper surface of the platform supporting plate through the lens bracket; the diaphragm is arranged on the upper surface of the platform supporting plate through the diaphragm bracket; the light collector is arranged on the lower surface of the platform supporting plate through a light collector bracket and is positioned on one side in front of the laser head emission port; the spectrometer is directly arranged on the lower surface of the platform supporting plate; the handle is of a combined hollow structure, the handle comprises a left half part and a right half part, and a connecting lead on the trigger switch sequentially penetrates through a vertical through hole on the bottom surface of the machine shell and a transverse groove on the bottom surface of the slide rail from the inside of the handle, enters the machine shell and is connected with the laser protection switch; the machine shell is of a combined structure and comprises a left shell and a right shell, and the sliding rail, the up-down fine adjustment device, the left-right fine adjustment device and the front-back fine adjustment device are all fixed on the inner wall of the right shell; the outer side of the trigger switch is surrounded by a trigger guard ring, one end of the trigger guard ring is connected to the front side surface of the handle, and the other end of the trigger guard ring is connected to the outer bottom surface of the shell.

4. The portable LIBS composition analyzer of claim 2, wherein: the support contains the ring of fixing in laser head the place ahead, and the central axis of ring and the coincidence of laser head transmission mouth, the upper surface fixed connection of bracing piece and platform backup pad is passed through to the lower part of ring, and the periphery of ring outwards evenly stretches out three the same installation pole, and three laser displacement sensor installs respectively on three installation pole, and the center of three laser displacement sensor is located same perpendicular to laser head transmission mouth the plane of central axis.

5. The portable LIBS composition analyzer of claim 4, wherein: the central axis of the three laser displacement sensor emitting ports intersects with one point on the central axis of the laser head emitting port, the included angles between the central axis of the three laser displacement sensor emitting ports and the central axis of the laser head emitting port are both alpha, and alpha is less than 25 degrees.

6. The portable LIBS composition analyzer of claim 5, wherein: the three laser displacement sensors are respectively installed on the side surfaces of the three installation rods through three fastening bolts, and the size of the included angle alpha is adjusted through the fastening bolts.

7. The portable LIBS composition analyzer of claim 2, wherein: the laser head is the cylindricality, and the laser head is transversely fixed mounting on the upper surface of platform backup pad through the fastening hoop on it, and the fastening hoop is located the front portion of platform backup pad, and fine setting device is through the side fixed connection that goes up of fastening hoop and laser head about, also through fastening hoop and the left surface or the right flank fixed connection of laser head about fine setting device.

8. The portable LIBS composition analyzer of claim 1, wherein: the control circuit comprises a microcomputer, a battery pack, a starting button, three signal converters, three piezoelectric controllers, a piezoelectric control USB concentrator and a power supply, signal output ports of three laser displacement sensors are respectively connected with position signal input ports of the microcomputer through the three signal converters, a position adjusting signal output port of the microcomputer is connected with input ports of the piezoelectric control USB concentrator and the power supply, three output ports of the piezoelectric control USB concentrator and the power supply are respectively connected with upper and lower fine tuning devices, left and right fine tuning devices and piezoelectric ceramic blocks in the front and rear fine tuning devices through the three piezoelectric controllers, a detection signal output port of a spectrometer is connected with a spectrum detection signal input port of the microcomputer, a control signal input port of a control module of the laser is connected with a laser control signal output port of the microcomputer, and the battery pack gives the microcomputer, the control module of the laser, the three laser displacement sensors and the power supply through the starting button The piezoelectric control USB concentrator and the power supply; the laser is a miniature laser, and the spectrometer is a miniature spectrometer.

9. The portable LIBS composition analyzer of claim 8, wherein: the type of the laser is as follows: DPS-1064-mini; the laser displacement sensor has the following types: under pine HL-G108-S-J; the types of the piezoelectric ceramic blocks are as follows: PC4QR form of thralabs; the types of the piezoelectric controller are as follows: type KPZ101 of Throlabs; the piezoelectric control USB concentrator and the power supply are of the following types: (ii) the KCH301 form of thralabs; the universal joint is a spherical universal joint; the spectrometer has the following model: Avaspec-Mini2048-UVI 10; the front part of the shell is in a frustum shape; the signal converter is a USB-RS-422/485 converter, the signal output port of the laser displacement sensor is an RS-422 interface or an RS-485 interface, and the position signal input port of the microcomputer is a USB interface.

10. The portable LIBS composition analyzer of claim 8, wherein: the box body comprises an upper cover and a lower box body, a display of a microcomputer is mounted on the inner top surface of the upper cover, a host, a battery pack, three piezoelectric controllers, a piezoelectric control USB concentrator and a power supply of the microcomputer are mounted in an interlayer of the bottom surface of the lower box body, a starting button is mounted on the upper portion of the inner side surface of the lower box body, a connecting cable between the upper cover and the lower box body penetrates out of the upper cover and then enters the interlayer of the bottom surface of the lower box body from the inner side wall of the lower box body, and a communication cable between the host box and a handheld collecting head penetrates out of the inner bottom surface of the lower box body and then enters the casing from a threading hole in the rear portion of the casing.

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