Detection device based on terahertz time-domain spectroscopy technology

Abstract

The invention discloses a detection device based on a terahertz time-domain spectroscopy technology, and relates to the technical field of detection equipment. The device comprises a box body, a femtosecond laser, a terahertz pulse device and a terahertz detector, three parallel detection chambers are arranged on the left side of the box body, a terahertz pulse generation chamber is arranged on the right side of the box body, a terahertz detector facing the light-transmitting square hole is arranged in the detector chamber, a femtosecond laser is arranged at the bottom of the terahertz pulse generation chamber, a time delay device is arranged above the femtosecond laser, and a light-transmitting square hole is formed in the box body. And the femtosecond laser emitted from the time delay device enters the terahertz pulse device. The three detection chambers are arranged to detect solid state, liquid state and gas state, and the problems that an existing instrument is troublesome in switching when detecting substances in three states, the precision is prone to being affected by air in the detection chambers and the like are solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of detection equipment, and in particular relates to a detection device based on terahertz time-domain spectroscopy technology. Background Art

[0002] Terahertz is an electromagnetic wave with a frequency of 0.1-10THz (1THz=1012Hz), and has a wide range of potential applications in information and communication technology, material identification, imaging, non-destructive testing, global environmental monitoring and other fields. Many biological and chemical compounds show obvious spectral responses in the terahertz range, and have great potential in environmental monitoring of atmospheric chemical composition (water, oxygen, ozone, chlorine and nitrogen compounds, etc.) and the detection and identification of substances. For some tissue tests, pathological conditions can be detected, and for solid tests, surface damage can be detected. However, the test bench of existing terahertz time-domain spectroscopy technology detection instruments only detects one of the solid, liquid and gaseous states. To change the state of the test substance, it is generally necessary to replace the stage or the structure. It is impossible to perform the required tests at any time in a single instrument.

[0003] The detection environment during the detection process has an impact on the detection accuracy. Different gas concentrations in the detection room or the presence of impurity gases and high moisture content will affect the detection accuracy.

[0004] To this end, we provide a detection device based on terahertz time-domain spectroscopy technology to solve the above problems. Summary of the Invention

[0005] The purpose of the present invention is to provide a detection device based on terahertz time-domain spectroscopy technology. By setting up three detection chambers for solid, liquid and gas detection, it solves the problems of the existing instrument being difficult to switch between three states of matter when detecting one instrument, and being easily affected by the air in the detection chamber, and the like.

[0006] To solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] The present invention is a detection device based on terahertz time-domain spectroscopy technology, comprising a box body, a femtosecond laser, a terahertz pulse device and a terahertz detector; three parallel detection chambers are provided on the left side of the box body, and a terahertz pulse generation chamber is provided on the right side; a detector chamber is provided at the bottom of each detection chamber, a light-transmitting square hole is provided at the bottom of the detection chamber, a glass plate detection platform is installed on the light-transmitting square hole, the glass plate detection platform is installed on the bottom of the detection chamber with a frame, a terahertz detector facing the light-transmitting square hole is installed in the detector chamber, a femtosecond laser is installed at the bottom of the terahertz pulse generation chamber, a delay device is installed above the femtosecond laser, the femtosecond laser emitted from the delay device enters the terahertz pulse device, and the terahertz pulses emitted by the terahertz pulse device are directed toward the three detection chambers;

[0008] The terahertz pulse device can move up and down in the upper half of the terahertz pulse generating chamber. A sealing cover is provided on the top of the box body. Three reflector columns corresponding to the detection chamber and inserted into the detection chamber are provided at the bottom of the sealing cover. A first reflector column is provided at the bottom of the reflector column, facing the terahertz pulse generating chamber and tilted upward. The first reflector forms a 45° angle with the horizontal plane. The three first reflectors rise upward in steps from left to right. The box body is provided with a sealed outward-opening door near the bottom of the front side wall of each detection chamber, and the box body is provided with a ventilation duct on the rear side wall of each detection chamber.

[0009] The present invention is further configured as follows: the terahertz pulse device includes a terahertz pulse emitter, an installation box, a lifting structure and a second reflector; a limit bar facing the side wall is respectively provided at the four corners of the installation box; a through limit hole is provided on the limit bar; an emitter mounting hole is provided on the left side wall of the installation box; a reflector cavity is provided on the right half of the bottom; the emitter mounting hole is communicated with the reflector cavity; a terahertz pulse emitter is installed in the emitter mounting hole; a second reflector is installed in the reflector cavity; the femtosecond laser emitted by the delay device is reflected from the second reflector into the terahertz pulse emitter; a limit rod is movable through the through limit hole; and a micro-lifting structure is provided at the bottom right side of the installation box.

[0010] The present invention is further configured such that the micro-lifting structure includes a screw sleeve, a screw and a micro-servo motor, the top of the screw sleeve is fixed on the bottom right side of the mounting box, the top of the screw is spirally inserted from the bottom end of the screw sleeve, and the bottom end of the screw is connected to the rotating shaft of the micro-servo motor.

[0011] The present invention is further configured as follows: the delay device includes a reflective box, a light inlet is provided at the right end of the bottom of the reflective box, and a light outlet is provided at the right end of the top; the reflective box is provided with a reflector facing the outer wall at the light inlet and the light outlet, and the two reflectors form an angle of 45° with the horizontal plane; two reflectors are provided on the left side wall of the reflective box, which are parallel to the reflectors at the light inlet and the light outlet and have opposite mirror surfaces; the light inlet and the light outlet can be in the same vertical plane or not in the same vertical plane.

[0012] The present invention is further configured such that the reflector at the light outlet is mounted on a transverse pushing assembly, which includes a transverse pushing servo motor, a horizontal limit rod and a transverse pushing screw. The reflector at the light outlet is an adjusting triangular block mirror, and four horizontal limit rods are movably inserted on the back of the adjusting triangular block mirror. A transverse pushing screw is connected to the rotating shaft of the transverse pushing servo motor, and the transverse pushing screw spiral is inserted from the center position of the back of the adjusting triangular block mirror.

[0013] The present invention is further configured such that the terahertz pulse emitter is provided with small terahertz pulse emitters distributed in an array, and by moving the adjustable triangular mirror, the femtosecond laser is reflected from the adjustable triangular mirror to different positions of the second reflector, thereby achieving different incident positions of the femtosecond laser irradiating the back of the terahertz pulse emitter, so as to enable different small terahertz pulse emitters to emit terahertz pulses.

[0014] The present invention is further configured such that the partition walls between the three detection chambers and between the detection chamber and the terahertz pulse generating chamber are all made of fused quartz glass, the thickness of the fused quartz glass is 5-6 mm, and the air pressure in each detection chamber is 0.5-1.2 atmospheres.

[0015] The present invention is further configured such that the three detection chambers are respectively a solid detection chamber, a liquid detection chamber and a gas detection chamber from left to right, and the terahertz detectors below the three solid detection chambers, liquid detection chambers and gas detection chambers are respectively terahertz detectors for solid, liquid and gas detection.

[0016] The present invention is further configured such that the box body and the sealing cover are both made of metal plates to form a closed shielding box.

[0017] The present invention has the following beneficial effects:

[0018] 1. The present invention performs three tests on solid, liquid and gaseous states respectively. During the test, the terahertz pulse device is raised and lowered so that the terahertz pulse emitter is at different horizontal heights, and the three first reflectors are at different horizontal heights. The terahertz pulses emitted by the terahertz pulse emitter are irradiated on different first reflectors and reflected onto the corresponding test platforms, thereby realizing the test of switching between three stages, without the need for multiple instruments to test multiple substances.

[0019] 2. The detection chamber of the present invention is a sealed environment, and air can be exhausted and other high-purity gases can be injected or the gas concentration can be reduced, which can reduce the impact of impurities in the gas on the detection.

[0020] Of course, any product implementing the present invention does not necessarily need to achieve all of the advantages described above at the same time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1This is a structural diagram of a detection device based on terahertz time-domain spectroscopy technology.

[0023] Figure 2 This is a schematic diagram of the cross-sectional structure of a detection device based on terahertz time-domain spectroscopy technology.

[0024] Figure 3 This is a structural diagram of an extension device that can adjust the light output position.

[0025] Figure 4 Schematic diagram of the explosion structure of a detection device based on terahertz time-domain spectroscopy technology.

[0026] Figure 5 A schematic diagram of the structure of the installation box.

[0027] In the accompanying drawings, the components represented by the reference numerals are as follows:

[0028] 1. Box body; 11. Detection chamber; 12. Terahertz pulse generating chamber; 13. Detector chamber; 14. Sealed outward-opening door; 15. Sealing cover; 2. Femtosecond laser; 3. Delay device; 31. Reflector; 32. Adjustment triangle mirror; 33. Horizontal push servo motor; 331. Horizontal push screw; 34. Horizontal limit rod; 4. Screw; 5. Mounting box; 50. Limit bar; 501. Limit rod; 51. Second reflector; 52. Screw sleeve; 53. Reflector cavity; 54. Emitter mounting hole; 6. Terahertz pulse emitter; 7. First reflector; 8. Frame; 81. Glass plate inspection platform; 9. Terahertz detector. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0030] See also Figure 1-5The present invention is a detection device based on terahertz time-domain spectroscopy technology, comprising a box body 1, a femtosecond laser 2, a terahertz pulse device and a terahertz detector 9; three parallel detection chambers 11 are provided on the left side of the box body 1, and a terahertz pulse generation chamber 12 is provided on the right side, and a detector chamber 13 is provided at the bottom of each detection chamber 11, and a light-transmitting square hole is provided at the bottom of the detection chamber 11, and a glass plate detection platform 81 is installed on the light-transmitting square hole, and the glass plate detection platform 81 is installed on the bottom of the detection chamber 11 with a frame 8, and a terahertz detector 9 facing the light-transmitting square hole is installed in the detector chamber 13, a femtosecond laser 2 is installed at the bottom of the terahertz pulse generation chamber 12, and a delay device 3 is installed above the femtosecond laser 2, the femtosecond laser emitted from the delay device 3 enters the terahertz pulse device, and the terahertz pulse emitted by the terahertz pulse device is directed toward the three detection chambers 11;

[0031] Three detection chambers are set up to detect three states of matter separately. Solid, liquid and gas detection are independent. A terahertz pulse device is used for position adjustment. Terahertz pulses can be emitted to different heights on the left side, irradiating different first reflectors 7, and then irradiating downward to the detection table for detection. The intensity of the terahertz pulse passes through the matter and enters the detector chamber 13. Affected by the properties of the matter, the terahertz detector 9 will detect the transmittance of different positions of the matter, as well as the transmittance of liquid and gas.

[0032] The whole is sealed to ensure that the air in the test room is exhausted and pure air or inert gas is injected, and even the air pressure can be reduced to improve the detection accuracy.

[0033] The terahertz pulse device can move up and down in the upper half of the terahertz pulse generating chamber 12. A sealing cover 15 is provided on the top of the box body 1. Three reflecting mirror columns corresponding to the detection chamber 11 and inserted into the detection chamber 11 are provided at the bottom of the sealing cover 15. A first reflecting mirror 7 facing the terahertz pulse generating chamber 12 and tilted upward is provided at the bottom of the reflecting mirror column. The first reflecting mirror 7 is at a 45° angle to the horizontal plane. The three first reflecting mirrors 7 rise upward in steps from left to right. The box body 1 is provided with a sealed outward-opening door 14 near the bottom of the front side wall of each detection chamber 11, and the box body 1 is provided with a ventilation duct on the rear side wall of each detection chamber 11.

[0034] The terahertz pulse device can be raised and lowered to emit terahertz pulses aimed at the three first reflectors 7. By simply adjusting the height, different detection chambers can be tested without changing the detection table. One instrument can complete the detection of multiple occupied substances.

[0035] The solid is fixed on the test table, the liquid uses a light-transmitting glass container as a carrier, and the gas can be directly filled into the test room (to replace the air in the test room).

[0036] The entire terahertz time-domain spectroscopy detection device is connected to computer data so that the computer can control the detection.

[0037] The terahertz pulse device includes a terahertz pulse emitter 6, an installation box 5, a lifting structure and a second reflector 51. The four corners of the installation box 5 are respectively provided with a limit block 50 facing the side wall, and the limit block 50 is provided with a through limit hole. The left wall of the installation box 5 is provided with an emitter mounting hole 54, and the right half of the bottom is provided with a reflector cavity 53. The emitter mounting hole 54 is communicated with the reflector cavity 53. The terahertz pulse emitter 6 is installed in the emitter mounting hole 54, and the second reflector 51 is installed in the reflector cavity 53. The femtosecond laser emitted by the delay device 3 is reflected from the second reflector 51 into the terahertz pulse emitter 6. A limit rod 501 is movable through the through limit hole. A micro-lifting structure is provided at the bottom right side of the installation box 5.

[0038] The limiting bar 50 has a fixed height and can slide on the four limiting rods 501 without swaying. The height can be adjusted by slowly raising and lowering the micro-lifting structure. After being reflected by the second reflector 51, the light is vertically directed to the back of the terahertz pulse emitter 6, where it receives the femtosecond laser light. The delay device 3 increases the distance and duration of the emitted femtosecond laser light directly hitting the terahertz pulse emitter 6 and also adjusts the light output position, which will be discussed in detail later.

[0039] The micro lifting structure includes a screw sleeve 52, a screw 4 and a micro servo motor. The top of the screw sleeve 52 is fixed on the bottom right side of the installation box 5. The top of the screw 4 is spirally inserted from the bottom end of the screw sleeve 52. The bottom end of the screw 4 is connected to the micro servo motor shaft.

[0040] The micro servo motor can slowly raise and lower the machine and accurately determine the lifting height.

[0041] The delay device 3 includes a reflective box, which has a light inlet at the right end of the bottom and a light outlet at the right end of the top. The reflective box is provided with a reflector 31 facing the outer wall at the light inlet and the light outlet, and the two reflectors 31 form an angle of 45° with the horizontal plane. Two reflectors 31 are provided on the left wall of the reflective box, which are parallel to the reflectors 31 at the light inlet and the light outlet and have opposite mirror surfaces. The light inlet and the light outlet can be in the same vertical plane or not.

[0042] The delay device 3 increases the light range and reduces the peak power just emitted to smooth the peak power, and then irradiates the terahertz pulse transmitter 6 for adjustment.

[0043] The reflector 31 at the light outlet is installed on the horizontal pushing assembly, and the horizontal pushing assembly includes a horizontal pushing servo motor 33, a horizontal limit rod 34 and a horizontal pushing screw 331. The reflector at the light outlet is an adjusting triangular block mirror 32. Four horizontal limit rods 34 are movably inserted on the back of the adjusting triangular block mirror 32. A horizontal pushing screw 331 is connected to the rotating shaft of the horizontal pushing servo motor 33. The horizontal pushing screw 331 is spirally inserted from the center position of the back of the adjusting triangular block mirror 32.

[0044] By adjusting the triangular mirror 32 , it is possible to achieve that the femtosecond lasers emitted at different positions hit different positions of the second reflector 51 and hit the back of the terahertz pulse emitter 6 at different positions.

[0045] The terahertz pulse emitter 6 is provided with small terahertz pulse emitters distributed in an array. By moving the adjusting triangular mirror 32, the femtosecond laser is reflected from the adjusting triangular mirror 32 to different positions of the second reflecting mirror 51, thereby achieving different incident positions of the femtosecond laser irradiating the back of the terahertz pulse emitter 6, so as to enable different small terahertz pulse emitters to emit terahertz pulses.

[0046] The terahertz pulse emitter 6 is of array type, which can enable different small terahertz pulse emitters to work after receiving the femtosecond laser, irradiating different positions of the second reflector 51, and irradiating downward to different positions of the material to scan the material. For solids and semi-solids, it will have a better effect of detecting different positions.

[0047] The partition walls between the three detection chambers 11 and between the detection chamber 11 and the terahertz pulse generating chamber 12 are all made of fused quartz glass. The thickness of the fused quartz glass is 5-6 mm. The air pressure in each detection chamber 11 is 0.5-1.2 atmospheres.

[0048] The air pressure and gas content in the detection chamber 11 can be adjusted, and detection under different gases can be performed to improve detection accuracy. The gas to be detected can be directly detected without the need for a box body for carrying objects, making detection more convenient.

[0049] The three detection chambers 11 are respectively a solid detection chamber, a liquid detection chamber and a gas detection chamber from left to right, and the terahertz detectors 6 below the three solid detection chambers, liquid detection chambers and gas detection chambers are respectively terahertz detectors 6 for solid, liquid and gas detection.

[0050] Targeted detection is possible. The first reflector 7 on the far left has the lowest height and is suitable for solid detection. The two liquids and gases on the right have larger volumes, so they are placed on the right.

[0051] The box body 1 and the sealing cover 15 are both made of metal plates to form a closed shielding box to shield external signals or electromagnetic interference that may affect the detection accuracy.

[0052] Throughout this specification, references to terms such as "one embodiment," "example," or "specific example" indicate that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of these terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0053] The preferred embodiments of the present invention disclosed above are intended only to help illustrate the present invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the content of this specification. These embodiments are selected and described in detail in this specification to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A detection device based on terahertz time-domain spectroscopy technology, comprising a box (1), a femtosecond laser (2), a terahertz pulse device and a terahertz detector (9); characterized in that: The box body (1) is provided with three parallel detection chambers (11) on the left side and a terahertz pulse generating chamber (12) on the right side. A detector chamber (13) is provided at the bottom of each detection chamber (11). A light-transmitting square hole is provided at the bottom of the detection chamber (11). A glass plate detection platform (81) is installed on the light-transmitting square hole. The glass plate detection platform (81) is installed on the bottom of the detection chamber (11) with a frame (8). A terahertz detector (9) facing the light-transmitting square hole is installed in the detector chamber (13). A femtosecond laser (2) is installed at the bottom of the terahertz pulse generating chamber (12). A delay device (3) is installed above the femtosecond laser (2). The femtosecond laser emitted from the delay device (3) enters the terahertz pulse device, and the terahertz pulse emitted by the terahertz pulse device is directed toward the three detection chambers (11). The terahertz pulse device can move up and down in the upper half of the terahertz pulse generating chamber (12); a sealing cover (15) is provided on the top of the box body (1); three reflective mirror columns corresponding to the detection chamber (11) and inserted into the detection chamber (11) are provided at the bottom of the sealing cover (15); a first reflective mirror (7) facing the terahertz pulse generating chamber (12) and tilted upward is provided at the bottom of the reflective mirror column; the first reflective mirror (7) forms an angle of 45° with the horizontal plane; the three first reflective mirrors (7) rise upward in steps from left to right; a sealed outward-opening door (14) is provided on the front side wall of each detection chamber (11) near the bottom of the box body (1); and a ventilation duct is provided on the rear side wall of each detection chamber (11).

2. The detection device based on terahertz time-domain spectroscopy technology according to claim 1, characterized in that: The terahertz pulse device comprises a terahertz pulse transmitter (6), a mounting box (5), a lifting structure and a second reflector (51); a limiting bar (50) facing the side wall is respectively provided at the four corner positions of the mounting box (5); a through limiting hole is provided on the limiting bar (50); a transmitter mounting hole (54) is provided on the left side wall of the mounting box (5); and a reflector cavity (53) is provided on the right half of the bottom; the transmitter mounting hole (54) is communicated with the reflector cavity (53); a terahertz pulse transmitter (6) is installed in the transmitter mounting hole (54); a second reflector (51) is installed in the reflector cavity (53); the femtosecond laser emitted by the delay device (3) is reflected from the second reflector (51) into the terahertz pulse transmitter (6); a limiting rod (501) is movably passed through the through limiting hole; and a micro lifting structure is provided at the bottom right of the mounting box (5).

3. The detection device based on terahertz time-domain spectroscopy technology according to claim 2, characterized in that: The micro-lifting structure comprises a screw sleeve (52), a screw (4) and a micro-servo motor. The top of the screw sleeve (52) is fixed on the bottom of the right side of the installation box (5). The top of the screw (4) is spirally inserted from the bottom of the screw sleeve (52). The bottom of the screw (4) is connected to the rotating shaft of the micro-servo motor.

4. The detection device based on terahertz time-domain spectroscopy technology according to claim 2, characterized in that: The delay device (3) comprises a reflective box, wherein a light inlet is provided at the right end of the bottom of the reflective box and a light outlet is provided at the right end of the top of the reflective box. The reflective box is provided with a reflector (31) facing the outer wall at the light inlet and the light outlet, and the two reflectors (31) form an angle of 45° with the horizontal plane. Two reflectors (31) are provided on the left side wall of the reflective box, which are parallel to the reflectors (31) at the light inlet and the light outlet and have opposite mirror surfaces. The light inlet and the light outlet can be in the same vertical plane or not.

5. The detection device based on terahertz time-domain spectroscopy technology according to claim 4, characterized in that: The reflector (31) at the light outlet is installed on a horizontal pushing assembly, and the horizontal pushing assembly includes a horizontal pushing servo motor (33), a horizontal limiting rod (34) and a horizontal pushing screw (331). The reflector at the light outlet is an adjusting triangular block mirror (32), and four horizontal limiting rods (34) are movably inserted on the back of the adjusting triangular block mirror (32). A horizontal pushing screw (331) is connected to the rotating shaft of the horizontal pushing servo motor (33), and the horizontal pushing screw (331) is spirally inserted from the center position of the back of the adjusting triangular block mirror (32).

6. The detection device based on terahertz time-domain spectroscopy technology according to claim 5, characterized in that: The terahertz pulse emitter (6) is provided with small terahertz pulse emitters distributed in an array. By moving the adjustment triangular mirror (32), the femtosecond laser is reflected from the adjustment triangular mirror (32) to different positions of the second reflector (51), thereby achieving different light incident positions of the femtosecond laser irradiating the back of the terahertz pulse emitter (6), so that different small terahertz pulse emitters can emit terahertz pulses.

7. The detection device based on terahertz time-domain spectroscopy technology according to claim 1, characterized in that: The partition walls between the three detection chambers (11) and between the detection chamber (11) and the terahertz pulse generating chamber (12) are all made of fused quartz glass, the thickness of the fused quartz glass is 5-6 mm, and the air pressure in each detection chamber (11) is 0.5-1.2 atmospheres.

8. The detection device based on terahertz time-domain spectroscopy technology according to claim 1, characterized in that: The three detection chambers (11) are respectively a solid detection chamber, a liquid detection chamber and a gas detection chamber from left to right, and the terahertz detectors (6) below the three solid detection chambers, the liquid detection chamber and the gas detection chamber are respectively terahertz detectors (6) for solid, liquid and gas detection.

9. The detection device based on terahertz time-domain spectroscopy technology according to claim 1, characterized in that: The box body (1) and the sealing cover (15) are both made of metal plates to form a closed shielding box.

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