CN214503363U

CN214503363U - Real-time monitoring device for virus particles in air

Info

Publication number: CN214503363U
Application number: CN202120345205.9U
Authority: CN
Inventors: 王强; 侯雷; 高静文
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-02-07
Filing date: 2021-02-07
Publication date: 2021-10-26
Anticipated expiration: 2031-02-07

Abstract

The utility model discloses a viral particle real-time supervision device in air, the device include infrared source interferometer module, laminar flow sample pipe module, shearing interference detection module, control and data processing module and signal collection processing method. The method has the advantages of compact design, high automation degree, sensitivity of single virus particles, rapid and accurate identification of virus types and the like. The design combines the molecular recognition characteristic of a Fourier transform infrared spectrometer and the high spatial resolution of a shearing interferometer to realize the rapid detection and recognition of biological samples at the molecular level and calculate the virus concentration in the air in real time. The design provides a solution for the rapid detection of viruses in private families and public places (including but not limited to hospitals, schools, stations and the like).

Description

Real-time monitoring device for virus particles in air

Technical Field

The utility model relates to a public health technical field especially relates to a viral particle real-time supervision device in air.

Background

Since 1 month of 2020, new coronavirus (abbreviated as new coronavirus, abbreviated as COVID-19) has been abused worldwide, which seriously affects people's daily life and work and causes huge economic loss. The prevention and treatment of new coronavirus is a common target in all countries of the world, and the main means is to detect the virus and cut off the transmission path of the virus. The most prominent mode of transmission of new coronaviruses is human-borne, and healthy people are susceptible to viral infections by inhalation of droplets if they come into close face-to-face contact with patients. Secondly, the carrier is passed, the patient discharges droplet and excrement with live virus, the surrounding environment and articles are polluted, and healthy people touch the mouth, nose and eyes of the patient to infect after touching the virus on the object surface. In addition, the national research team has confirmed aerosol transmission of new coronavirus and discovered new coronavirus from the toilet air used by patients. Compare the droplet large granule, the aerosol volume is littleer, floats easily and stops in the space, and propagation distance is also wider, and hidden danger is bigger. Moreover, aerosol transmission often occurs in special, relatively confined spaces, such as hospitals. Rapid detection of viruses in public and private (enclosed) spaces is therefore an urgent priority.

According to the literature search, no device for directly detecting virus particles (80-100nm in size) in the air exists at present. The traditional Fourier transform infrared spectrometer analyzes the structure and the composition of a substance by utilizing the principle that different compounds have different infrared absorption spectrums, but the test object is a macroscopic sample and is not suitable for virus particle identification at the molecular level. The multi-component gas analysis Fourier infrared spectrometer shown in the patent No. CN108519344A can monitor and analyze gas components, but the sensitivity does not reach the detection capability of single molecule level, and virus particles with rare content in the air can not be detected.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a viral particle real-time supervision device in air aims at solving and monitors time measuring to gas composition among the prior art, and sensitivity can not reach the detection capability of unimolecular level, can not detect the technical problem of the viral particle that content is rare in the air.

In order to achieve the above object, the utility model provides an airborne virus particle real-time supervision device, including infrared source interferometer module, laminar flow sample tube module, shearing interference detection module and control and data processing module, laminar flow sample tube module includes miniature sampling air pump, air inlet and sample cell, the both ends of sample cell are provided with respectively the air pump with the air inlet, the both sides of sample cell are provided with respectively infrared source interferometer module with shearing interference detection module, control and data processing module respectively with the air pump infrared source interferometer module with shearing interference detection module electric connection.

The infrared light source interferometer module comprises an infrared light source, an off-axis parabolic reflector, an interferometer and a beam expanding assembly, wherein the interferometer and the infrared light source are respectively arranged on the same side of the off-axis parabolic reflector, and the beam expanding assembly is arranged between the sample tube and the interferometer.

Wherein, the interferometer includes beam splitter, fixed mirror, movable mirror and voice coil motor, the beam splitter set up in off-axis parabolic mirror with between the movable mirror, one side of beam splitter is provided with fixed mirror, the beam splitter is kept away from the opposite side of fixed mirror is provided with expand the beam subassembly, voice coil motor set up in the side of movable mirror.

The beam expanding assembly comprises a small-focus convex lens and a large-focus convex lens, wherein the large-focus convex lens is respectively arranged in parallel with the small-focus convex lens and the sample tubes and is positioned between the small-focus convex lens and the sample tubes.

The infrared light source interferometer module further comprises a helium-neon laser, a first reflector, a second reflector and a visible light photoelectric detector, the first reflector is arranged between the off-axis parabolic reflector and the beam splitter, the first reflector is close to one side, adjacent to the beam splitter, of the helium-neon laser, the second reflector is arranged between the small-focal-length convex lens and the beam splitter, and the second reflector is close to one side of the beam splitter and is provided with the visible light photoelectric detector.

Wherein, shearing interference detection module includes first convex lens, second convex lens, third speculum, grating, high accuracy piezoelectric actuator and collection module, the second convex lens respectively with first convex lens with the sample cell parallel arrangement relatively, and be located first convex lens with between the sample cell, the second convex lens is kept away from one side of first convex lens is provided with the third speculum, the grating set up in the third speculum with collect between the module, high accuracy piezoelectric actuator set up in the side of grating.

The control and data processing module comprises a movable mirror position calculation submodule, a displacement control submodule, an air pump control submodule and a data processing submodule, the movable mirror position calculation submodule is electrically connected with the visible light photoelectric detector, the displacement control submodule is electrically connected with the voice coil motor, the displacement control submodule is also electrically connected with the high-precision piezoelectric driver, the air pump control submodule is electrically connected with the air pump, and the data processing submodule is in signal connection with the collection module.

The beneficial effects of the utility model are embodied in: the infrared light source emits infrared light, light beams are guided into the interferometer in parallel through the off-axis parabolic reflector, and the light beams interfered by the interferometer are expanded into infrared light beams with larger diameters through a beam expanding device consisting of the small-focal-length convex lens and the large-focal-length convex lens; the air pump enables negative pressure to be formed in the sample tube so as to ensure that external sample air smoothly passes through the air inlet tube and enters the sample tube in a laminar flow state, the expanded light beam irradiates the sample tube, and virus particles in the air can generate disturbance on an incident infrared light field and enter the shear interference detection module as a signal light beam; the signal beam is reflected by the third reflector before being incident on the grating, shearing interference is generated when the signal beam is incident on the surface of the grating, the high-precision piezoelectric driver drives the grating to make S-point reciprocating displacement (S >4) in one period along the diagonal direction, S types of displacement of the grating are set to correspond to S types of interference patterns, and the interference patterns are collected by the collection module and transmitted to the signal collection module for data processing; the real-time monitoring device for virus particles in the air has compact design and high automation degree, and can be flexibly applied to virus detection in the air of private families and public places; the instrument directly detects air without sample preparation; the instrument uses a shearing interference principle and utilizes a rapid algorithm to realize the real-time detection of virus particles at a single molecular level. The microscope is suitable for the fields of daily life, public transportation, medical detection, life science and the like.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a device for monitoring airborne virus particles in real time according to the present invention.

Fig. 2 is a schematic diagram of an improved hartmann grating of the present invention.

Fig. 3 is a schematic diagram of a signal collection submodule in embodiment 1.

Fig. 4 is a schematic diagram showing the cooperation of air flow, grating arrangement and reciprocal scanning of the movable mirror in example 1.

Fig. 5 is a schematic diagram of a data processing flow in embodiment 1.

FIG. 6 is a schematic diagram showing the cooperation of air flow, grating arrangement and reciprocal scanning of the movable mirror in example 2.

Fig. 7 is a two-dimensional matrix diagram of the CCD imager in example 2.

Fig. 8 is a schematic diagram of a data processing flow in embodiment 2.

1-infrared light source interferometer module, 11-infrared light source, 12-off-axis parabolic reflector, 13-beam splitter, 14-fixed reflector, 15-movable reflector, 16-voice coil motor, 17-helium-neon laser, 18-reflector, 19-reflector, 110-visible light photoelectric detector, 111-small focal length convex lens, 112-large focal length convex lens, 2-laminar flow sample tube module, 21-air inlet, 22-sample tube, 23-speed regulation micro sampling air pump, 3-shearing interference detection module, 31-first convex lens, 32-second convex lens, 33-third reflector, 34-grating, 35-high precision piezoelectric driver, 36-signal collection module, 361-Fourier transform convex lens, 362-a high-pass spatial filter, 363-a second inverse Fourier transform convex lens, 364-an infrared detector, a 4-control and data processing module, 41-a movable mirror position calculation sub-module, 42-a displacement control sub-module, 43-an air pump control sub-module and 44-a data processing sub-module.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary and intended to be used for explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it is to be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. In addition, in the description of the present invention, "a plurality" means two or more unless specifically limited otherwise.

Referring to fig. 1 to 5, embodiment 1: the utility model provides a viral particle real-time supervision device in air, includes infrared light source interferometer module 1, laminar flow sample tube module 2, cuts interference detection module 3 and control and data processing module 4, laminar flow sample tube module 2 adopts miniature sampling air pump, air inlet 21 and sample cell 22, the both ends of sample cell 22 are provided with respectively the air pump 23 with air inlet 21, the both sides of sample cell 22 are provided with respectively infrared light source interferometer module 1 with cut interference detection module 3, control and data processing module 4 respectively with the air pump 23 infrared light source interferometer module 1 with cut interference detection module 3 electric connection.

In this embodiment, the infrared light source interferometer module 1 uses the infrared light source to emit infrared light, light beams are guided in parallel to the interferometer by the off-axis parabolic reflector 12, and the light beams interfered by the interferometer are expanded into infrared light beams with a larger diameter by a beam expander composed of the small focal length convex lens 111 and the large focal length convex lens 112; the air pump 23 forms negative pressure in the sample tube 22 to ensure that the external sample air smoothly passes through the air inlet 21 tube and enters the sample tube 22 in a laminar flow state, the air pump 23 is a speed-regulating micro-sampling air pump 23, the power of the air pump is regulated to control the speed of the sample air, and the speed of the air pump is low enough to ensure that the air flow is in the laminar flow state (if the air flow is in a turbulent flow state, the turbulent track of virus particles can reduce the precision of a detection result); the velocity v of the sample air should be small by Re μ/(ρ × D) 0.57m/s, where Re is the reynolds number (reynolds number for laminar flow regime is less than 1000) and μ hydrodynamic viscosity (air is 1.48 × 10)^-5Pa.s), ρ is the density of the fluid (1.29 Kg/m of air)³) D sample tube 22 diameter (0.02 m); to ensure the laminar flow state, the power of the air pump 23 is set in this embodiment so that the sample air flow rate is 0.05m/s, and accordingly, the time for passing through the infrared beam with the diameter of 4cm is 0.040/0.05 s-0.8 s; the expanded light beam irradiates the sample tube 22, and virus particles in the air can generate disturbance on an incident infrared light field and enter the shear interference detection module 3 as a signal light beam; the signal beam is reflected by the third mirror 33 before being incident on the grating 34, and generates shearing interference when being incident on the surface of the grating 34, the high-precision piezoelectric driver 35 drives the grating 34 to make 5-point round-trip displacement in one period along the diagonal direction, and the 5 displacement settings of the grating 34Corresponding to the 5 interference patterns, the interference patterns are collected by the collection module 36 and transmitted to the control and data processing module 4; the control and data processing module 4 is used for controlling the running time and the running sequence of each component and processing data; the real-time monitoring device for the virus particles in the air has compact design and high automation degree, and can be flexibly applied to the detection of the virus in the air of private families and public places; the instrument detects air directly without sample preparation. The instrument uses a shearing interference principle and utilizes a rapid algorithm to realize the real-time detection of virus particles at a single molecular level. The microscope is suitable for the fields of daily life, public transportation, medical detection, life science and the like.

Further, the infrared light source interferometer module 1 includes an infrared light source 11, an off-axis parabolic reflector 12, an interferometer and a beam expanding assembly, the interferometer and the infrared light source 11 are respectively disposed on the same side of the off-axis parabolic reflector 12, and the beam expanding assembly is disposed between the sample tube 22 and the interferometer; the interferometer comprises a beam splitter 13, a fixed reflector 14, a movable reflector 15 and a voice coil motor 16, wherein the beam splitter 13 is arranged between the off-axis parabolic reflector 12 and the movable reflector 15, the fixed reflector 14 is arranged on one side of the beam splitter 13, the beam expansion assembly is arranged on the other side, away from the fixed reflector 14, of the beam splitter 13, and the voice coil motor 16 is arranged on the side surface of the movable reflector 15; the beam expanding assembly comprises a small-focus convex lens 111 and a large-focus convex lens 112, wherein the large-focus convex lens 112 is respectively arranged in parallel with the small-focus convex lens 111 and the sample tube 22, and is located between the small-focus convex lens 111 and the sample tube 22.

In the present embodiment, the infrared light source 11 is a Nernst lamp infrared light source, and emits infrared light (wavelength is 2.5-50 μm, wave number is 4000-^-1) The light beam is led into the interferometer in parallel through the off-axis parabolic mirror 12, and the light beam is divided into two by the beam splitter 13; one reflected to the fixed mirror 14 and transmitted through the beam splitter 13; the other reaches after transmitting through the beam splitter 13The movable mirror 15 is reflected, then reflected again by the beam splitter 13, and finally the two light beams are merged and interfered, the strength of the interference is determined by the displacement of the movable mirror 15, wherein the movable mirror 15 is driven by the voice coil motor 16, and the maximum displacement is 1.0 mm; the interfered infrared light passes through the beam expanding device composed of the small focal length convex lens 111 and the large focal length convex lens 112, and the beam diameter is expanded to 0.040 m.

Further, the infrared light source interferometer module 1 further includes a he-ne laser 17, a first reflector 18, a second reflector 19 and a visible light photodetector 110, the first reflector 18 is disposed between the off-axis parabolic reflector 12 and the beam splitter 13, the first reflector 18 is disposed near the helium-ne laser 17 on one side adjacent to the beam splitter 13, the second reflector 19 is disposed between the small focal length convex lens 111 and the beam splitter 13, and the visible light photodetector 110 is disposed near one side of the beam splitter 13 of the second reflector 19.

In the present embodiment, the position of the movable mirror 15 is determined by: the laser light (632.8nm) emitted by the he-ne laser 17 is introduced into the optical path of the interferometer by the first reflecting mirror 18, the same interference process as the infrared light occurs, and the interference light beam is guided into the visible light photodetector 110 by the second reflecting mirror 19; from the interference properties of the optical field, a coherent-enhanced optical signal appears for every half wavelength (316.4nm) of the movement of the movable mirror 15, from which the real-time position of the movable mirror 15 can be calculated.

Further, shearing interference detection module 3 includes first convex lens 31, second convex lens 32, third speculum 33, grating 34, high accuracy piezoelectric actuator 35 and collection module 36, second convex lens 32 respectively with first convex lens 31 with the relative parallel arrangement of sample cell 22, and be located first convex lens 31 with between the sample cell 22, second convex lens 32 keeps away from one side of first convex lens 31 is provided with third speculum 33, grating 34 set up in third speculum 33 with between the collection module 36, high accuracy piezoelectric actuator 35 set up in the side of grating 34.

In the present embodiment, the grating 34 is a modified hartmann grating, as shown in fig. 2, wherein the period P in the diagonal direction is 1 μm, the signal beam is reflected by the third mirror 33 before being incident on the grating 34, and generates shearing interference when being incident on the surface of the grating 34, the high-precision piezoelectric driver 35 drives the grating 34 to make 5-point round-trip displacement in one period in the diagonal direction, the 5 displacement settings of the grating 34 correspond to 5 interference patterns, and the interference patterns are collected by the collection module 36 and transmitted to the control and data processing module 4.

Further, the signal collection module 36 includes a convex fourier transform lens 361, a high-pass spatial filter 362, a convex second inverse fourier transform lens 363, and an infrared detector 364, the convex fourier transform lens 361 is disposed on a side surface of the grating 34, the high-pass spatial filter 362 is disposed between the convex inverse fourier transform lens 363 and the convex fourier transform lens 361, and the infrared detector 364 is disposed on a side of the convex inverse fourier transform lens 363 away from the high-pass spatial filter 362.

In this embodiment, the signal collection module 36 operates according to the principle shown in fig. 3: the interference pattern sequentially enters the fourier transform convex lens 361, the high-pass spatial filter 362 and the inverse fourier transform convex lens 363, wherein the fourier transform convex lens 361 is used for performing spatial fourier transform on the incident interference pattern at the right focal plane, the high-pass spatial filter 362 at the left focal plane filters out the low-frequency part of the interference pattern, only the high-frequency part (namely, the signal light with virus particle information) passes through the high-pass spatial filter 362, and finally the signal light is subjected to inverse fourier transform through the inverse fourier transform convex lens 363 to be imaged on the infrared detector 364, and the infrared detector 364 transmits the signal to the data processing sub-module 44. Wherein the right focal plane of the inverse fourier transform convex lens 363 coincides with the left focal plane of the fourier transform convex lens 361, and the left focal plane thereof coincides with the infrared detector 364.

Further, the control and data processing module 4 includes a movable mirror position calculation submodule 41, a displacement control submodule 42, an air pump control submodule 43 and a data processing submodule 44, the movable mirror position calculation submodule 41 is electrically connected to the visible light photodetector 110, the displacement control submodule 42 is electrically connected to the voice coil motor 16, the displacement control submodule 42 is further electrically connected to the high-precision piezoelectric driver 35, the air pump control submodule 43 is electrically connected to the air pump 23, and the data processing submodule 44 is in signal connection with the collection module 36.

In the present embodiment, the movable mirror position calculation submodule 41 receives the signal of the visible light photodetector 110, and calculates the real-time displacement of the movable mirror 15; the displacement control submodule 42 outputs a control signal to the voice coil motor 16 to make the voice coil motor perform reciprocating periodic motion, and simultaneously the displacement control submodule 42 outputs a control signal to the high-precision piezoelectric driver 35 to make the high-precision piezoelectric driver perform 5-point reciprocating displacement within one grating 34 period along the diagonal direction of the grating 34; the air pump control submodule 43 outputs a control signal to the air pump 23 to ensure that the air in the sample tube 22 keeps uniform laminar flow motion; the data processing sub-module 44 receives the data collected by the infrared detector 364 for data processing; wherein the 5-point round trip displacement of the grating 34 and the round trip scanning of the movable mirror 15 are coordinated under the control of the displacement control sub-module 42; specifically, as shown in fig. 4: the infrared-illuminated portion of the sample tube 22 is uniformly divided into 5 regions: a, B, C, D, E, the sample air flowed through these 5 regions at a constant velocity, and the total flow time was also divided into 5 time segments (each time segment was 0.8s/5 ═ 0.16 s). The grating 34 is set to a displacement in the diagonal direction in each period (5-point displacement size: 0, P/5, 2P/5, 3P/5, 4P/5); meanwhile, in each time period, the movable reflector 15 performs constant-speed scanning from small to large (or from large to small), and the scanning directions in adjacent time periods are opposite; in each time period, the infrared photoelectric detector samples signals, and the sampling rate is 10 KHz.

The data processing method is shown in fig. 5, and specifically includes the following steps:

(1) during each time period when the sample air flows through the sample tube 22, the infrared photoelectric detector collects signals N times, wherein N is 0.16s 10KHz 1600, and the finally obtained raw data is a two-dimensional matrix of 5 rows and N columns: the 5 rows represent 5 time periods of sample air passing through the sample tube 22 (i.e., 5 settings of the grating 34); the N columns represent the N sampling instants within each time segment. The matrix elements represent the photo-electric signals collected at a certain time, such as I _ B2, where in the B region of the sample cell 22 (i.e. the grating 34 is set to P/5 displacement), the photo-electric signals are I _ B2 at the 2 nd sampling time;

(2) the 5 x N matrix is rearranged for all time segments according to the absolute position of the movable mirror 15. Specifically, in the time periods a, C, and E, i.e., the sampling times [ a1 to AN ], [ C1 to CN ], and [ E1 to EN ] correspond to the movable mirror 15 from the minimum displacement to the maximum displacement, while the time periods B and D have the opposite correspondence; for this purpose, the data of time segments B and D (i.e. row 2 and row 4 of the matrix) are arranged in the reverse direction; obtaining a new matrix as shown in fig. 5, in which each column of elements corresponds to the same position of said movable mirror 15;

(3) for 5 elements of each column, a trigonometric function fitting is performed, the fitting function being S _ I ═ Io _ I + I _ I × (x + Φ), where I is 1, 2 … N. Wherein S _ I is the modulation change of the grating 34 in the diagonal direction to the interference pattern, Io _ I is the unfiltered low-frequency background light intensity, x is the phase difference corresponding to the displacement of the grating 34, phi is the initial phase, and I _ I is the total average light intensity of the signal light, i.e. the signal to be obtained; the fitting is carried out on the N columns of elements to obtain the signal intensity under N positions of the movable reflecting mirror 15, which is similar to the signal of the traditional Fourier transform infrared spectrometer, and the result is a1 x N vector;

(4) performing Fourier transform on the vector to obtain a signal spectrum; in addition, the sample air is not filled (the air inlet 21 of the sample tube 22 is closed), the detection is carried out, and the data processing process is repeated, so that a group of infrared spectrums without signal light are obtained and used as reference spectrums; then the signal is spectrallyLight intensity normalization for each wavelength: the signal spectrum/reference spectrum is used for obtaining a detection spectrum; finally, comparing the absorption peak (i.e. the wavelength with the normalized value less than 1) in the detection spectrum with the Fourier transform infrared spectrum library stored in the data processing submodule 44, the category of the virus particles can be determined; by calculating the total volume V of the air introduced into the sample tube 22, the concentration D of the virus in the measured space can be obtained as M/V. Wherein M is the number of virus particles detected and V.v.pi.D²V is the air flow rate, D is the diameter of the sample tube 22, and t is the air time.

Referring to fig. 6 to 8, embodiment 2: the utility model provides a viral particle real-time supervision device in air, includes infrared light source interferometer module 1, laminar flow sample tube module 2, cuts interference detection module 3 and control and data processing module 4, laminar flow sample tube module 2 adopts miniature sampling air pump, air inlet 21 and sample cell 22, the both ends of sample cell 22 are provided with respectively the air pump 23 with air inlet 21, the both sides of sample cell 22 are provided with respectively infrared light source interferometer module 1 with cut interference detection module 3, control and data processing module 4 respectively with the air pump 23 infrared light source interferometer module 1 with cut interference detection module 3 electric connection.

In this embodiment, the infrared light source interferometer module 1 uses the infrared light source to emit infrared light, light beams are guided in parallel to the interferometer by the off-axis parabolic reflector 12, and the light beams interfered by the interferometer are expanded into infrared light beams with a larger diameter by a beam expander composed of the small focal length convex lens 111 and the large focal length convex lens 112; the air pump 23 forms negative pressure in the sample tube 22 to ensure that the external sample air smoothly passes through the air inlet 21 tube and enters the sample tube 22 in a laminar flow state, the air pump 23 is a speed-regulating micro-sampling air pump 23, the power of the air pump is regulated to control the speed of the sample air, and the speed of the air pump is low enough to ensure that the air flow is in the laminar flow state (if the air flow is in a turbulent flow state, the turbulent track of virus particles can reduce the precision of a detection result); the velocity v of the sample air should be small by Re μ/(ρ D) 0.57m/s, where Re is the Reynolds number (layer)Reynolds number corresponding to flow regime less than 1000), μ hydrodynamic viscosity (air 1.48 × 10)^-5Pa.s), ρ is the density of the fluid (1.29 Kg/m of air)³) D sample tube 22 diameter (0.02 m); to ensure the laminar flow state, the power of the air pump 23 is set in this embodiment so that the sample air flow rate is 0.05m/s, and accordingly, the time for passing through the infrared beam with the diameter of 4cm is 0.040/0.05 s-0.8 s; the expanded light beam irradiates the sample tube 22, and virus particles in the air can generate disturbance on an incident infrared light field and enter the shear interference detection module 3 as a signal light beam; the signal beam is reflected by the third mirror 33 before being incident on the grating 34, and generates shearing interference when being incident on the surface of the grating 34, the high-precision piezoelectric driver 35 drives the grating 34 to make 5-point round-trip displacement in one period along the diagonal direction, the 5 displacement settings of the grating 34 correspond to 5 interference patterns, and the interference patterns are collected by the collection module 36 and transmitted to the control and data processing module 4; the control and data processing module 4 is used for controlling the running time and the running sequence of each component and processing data; the real-time monitoring device for the virus particles in the air has compact design and high automation degree, and can be flexibly applied to the detection of the virus in the air of private families and public places; the instrument directly detects air, does not need to carry out sample preparation, uses a shearing interference principle, and can realize real-time detection of virus particles at a single molecular level by utilizing a rapid algorithm. The microscope is suitable for the fields of daily life, public transportation, medical detection, life science and the like.

In this embodiment, the infrared light source emits infrared light (wavelength of 2.5-50 μm, wave number of 4000-^-1) The light beam is led into the interferometer in parallel through the off-axis parabolic mirror 12, and the light beam is divided into two by the beam splitter 13; one reflected to the fixed mirror 14 and transmitted through the beam splitter 13; the other beam reaches the movable mirror 15 after passing through the beam splitter 13 and is reflected, then is reflected by the beam splitter 13 again, and finally the two beams are merged and interfered, wherein the strength of the interference is determined by the displacement of the movable mirror 15, wherein the movable mirror 15 is driven by the voice coil motor 16, and the maximum displacement is 1.0 mm; the interfered infrared light passes through the beam expanding device composed of the small focal length convex lens 111 and the large focal length convex lens 112, and the beam diameter is expanded to 0.040 m.

In this embodiment, the grating 34 is a modified hartmann grating, as shown in fig. 2, wherein a period P in a diagonal direction is 1 μm, a signal beam is reflected by the third mirror 33 before being incident on the grating 34, and shear interference is generated when being incident on the surface of the grating 34, the high-precision piezo driver 35 drives the grating 34 to make 5-point displacement in one period in the diagonal direction, the 5 displacement settings of the grating 34 correspond to 5 interference patterns, and the collection module 36 is a CCD imaging device and functions to directly record the interference patterns after the grating 34.

In the present embodiment, the movable mirror position calculation submodule 41 receives the signal of the visible light photodetector 110, and calculates the real-time displacement of the movable mirror 15; the displacement control submodule 42 outputs a control signal to the voice coil motor 16 to make the voice coil motor perform reciprocating periodic motion, and simultaneously the displacement control submodule 42 outputs a control signal to the high-precision piezoelectric driver 35 to make the high-precision piezoelectric driver perform 5-point reciprocating displacement within one period of the grating 34 along the diagonal direction of the grating 34; the air pump control submodule 43 outputs a control signal to the air pump 23 to ensure that the air in the sample tube 22 keeps uniform laminar flow motion; the data processing sub-module 44 receives the data collected by the collection module 36(CCD imaging device) for data processing; wherein the 5-point round trip displacement of the grating 34 and the round trip scanning of the movable mirror 15 are coordinated under the control of the displacement control sub-module 42; specifically, as shown in fig. 6: the infrared-illuminated portion of the sample tube 22 is uniformly divided into 5 regions: a, B, C, D, E, the sample air flowed through these 5 regions at a constant velocity, and the total flow time was also divided into 5 time segments (each time segment was 0.8s/5 ═ 0.16 s). The grating 34 is set to a displacement in the diagonal direction in each period (5-point displacement size: 0, P/5, 2P/5, 3P/5, 4P/5); meanwhile, in each time period, the movable reflector 15 performs constant-speed scanning from small to large (or from large to small), and the scanning directions in adjacent time periods are opposite; meanwhile, the CCD imaging device is also uniformly divided into 5 regions: a, B, C, D, E, the sampling rate is 10 KHz.

The data structure is as follows: acquiring signals N times in each time period when the sample air flows through the sample tube 22, that is, in each region of the collection module 36(CCD imaging device), where N is 0.16s 10KHz 1600, the finally obtained raw data is 5 x N frames of data, each frame of data is a two-dimensional matrix, the size of the matrix depends on the number of pixels in each region of the collection module 36(CCD imaging device), in this example, the number of pixels in each region is 500 x 800, that is, the size of each frame (two-dimensional matrix) is 500 x 800; a 5 x N table as shown in fig. 7, wherein 5 rows represent 5 time periods (corresponding to 5 settings of the grating 34) for sample air passing through the sample tube 22; the N columns represent the N sampling instants within each time segment. The elements in the table are a frame of data (500 rows and 800 columns of the two-dimensional matrix), such as B2: a frame of image (500 rows and 800 columns of the two-dimensional matrix) captured by the collection module 36(CCD imaging device) at the 2 nd sampling instant in the B region of the sample cell 22 (i.e., the grating 34 is set to P/5 displacement).

The data processing method is shown in fig. 8, and includes the following steps:

(1) respectively performing Fourier transform on 5 × N frame images (two-dimensional matrixes) in a data table, filtering low-frequency spatial information (namely background light) of each frame, only retaining high-frequency spatial information (namely signal light containing virus particle information), and performing inverse Fourier transform on the high-frequency spatial information to obtain the real-space imaging of the signal light without background light interference; the result is still a 5 x N table with elements in a two-dimensional matrix of 500 rows and 800 columns;

(2) the 5 x N table is rearranged for all time segments according to the absolute position of the movable mirror 15. Specifically, in the periods a, C, and E, i.e., [ a1 to AN ], [ C1 to CN ], and [ E1 to EN ] correspond to the movable mirror 15 from the minimum displacement to the maximum displacement, while the periods B and D have the opposite correspondence. To this end, time periods B and D (i.e. row 2 and row 4 of the table) are reversed, resulting in a new table as shown in fig. 8, where each column corresponds to the same movable mirror 15 position;

(3): the signal of the collection module 36(CCD imaging device) is averaged over all time periods:

first, for each position of the movable mirror 15, i.e., 5 two-dimensional matrices in each column of the above table, elements at the same position in the 5 matrices are fitted to a trigonometric function. Specifically, for example, the ith row and j column elements of the 1 st column and 5 th matrix are taken out: a1_ ij, BN _ ij, C1_ ij, DN _ ij, E1_ ij, and fitting with a trigonometric function S _ ij ═ Io _ ij + I _ ij × cos (x + Φ), where I ═ 1, 2 … 500, j ═ 1, 2 … 800. In the formula, S _ ij is a modulation change of the light intensity at I row and j column caused by the movement of the grating 34 in the diagonal direction, Io _ ij is unfiltered low-frequency background light intensity, x is a phase difference corresponding to the displacement of the grating 34, phi is an initial phase, and a fitting parameter I _ ij is an average light intensity of the signal light at I row and j column.

After all the same position elements of the 5 matrixes in the 1 st column are fitted, the obtained fitting parameters I _ ij are averaged to obtain the signal light intensity I _1 of the 1 st column (at the 1 st moment). Specifically, for 500 × 800 fitting parameters I _ ij, the signals were averaged;

repeating the fitting and averaging process on all N columns (corresponding to N sampling moments or N positions of the movable reflector 15) in the table to finally obtain signals similar to those of the traditional Fourier transform infrared spectrometer, namely 1 x N vectors;

(4): and performing Fourier transform on the vector to obtain a signal spectrum. In addition, the sample air is not passed (the air inlet 21 is closed, the detection is carried out and the data processing process is repeated to obtain a group of infrared spectrums without signal light as reference spectrums, then the light intensity of each wavelength in the signal spectrums is normalized, namely the signal spectrums/the reference spectrums, so that the detection spectrums are obtained, and finally the absorption peak (namely the wavelength with the normalized value less than 1) in the detection spectrums is compared with the Fourier transform infrared spectrum library stored in the data processing submodule 44, so that the category of the virus particles can be determined;

by calculating the total volume V of the air introduced into the sample tube 22, the concentration D of the virus in the space to be measured can be obtained as M/V. Wherein M is the number of virus particles detected and V.v.pi.D²V is the air flow rate, D is the diameter of the sample tube 22, and t is the air time.

The utility model has compact design and high automation degree, and can be flexibly applied to the virus detection in the air of private families/public places; the instrument directly detects air without sample preparation; the instrument uses a shearing interference principle and utilizes a rapid algorithm to realize the real-time detection of virus particles at a single molecular level. The microscope is suitable for the fields of daily life, public transportation, medical detection, life science and the like.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.

Claims

1. The utility model provides a viral particle real-time supervision device in air, its characterized in that, includes infrared source interferometer module, laminar flow sample tube module, cuts interference detection module and control and data processing module, laminar flow sample tube module includes miniature sampling air pump, air inlet and sample cell, the both ends of sample cell are provided with respectively the air pump with the air inlet, the both sides of sample cell are provided with respectively infrared source interferometer module with cut interference detection module, control and data processing module respectively with the air pump infrared source interferometer module with cut interference detection module electric connection.

2. The device for real-time monitoring of airborne virus particles according to claim 1, wherein the infrared source interferometer module comprises an infrared source, an off-axis parabolic reflector, an interferometer and a beam expanding assembly, the interferometer and the infrared source are respectively disposed on the same side of the off-axis parabolic reflector, and the beam expanding assembly is disposed between the sample tube and the interferometer.

3. The device for real-time monitoring of airborne virus particles according to claim 2, wherein the interferometer comprises a beam splitter, a fixed mirror, a movable mirror and a voice coil motor, the beam splitter is disposed between the off-axis parabolic mirror and the movable mirror, the fixed mirror is disposed on one side of the beam splitter, the beam expanding assembly is disposed on the other side of the beam splitter away from the fixed mirror, and the voice coil motor is disposed on the side of the movable mirror.

4. The device for real-time monitoring of airborne virus particles according to claim 3, wherein the beam expander assembly comprises a small focal length convex lens and a large focal length convex lens, and the large focal length convex lens is disposed in parallel with and between the small focal length convex lens and the sample tube, respectively.

5. The device for real-time monitoring of airborne virus particles according to claim 4, wherein said infrared source interferometer module further comprises a he-ne laser, a first mirror, a second mirror and a visible light photodetector, said first mirror is disposed between said off-axis parabolic mirror and said beam splitter, said first mirror is disposed adjacent to said beam splitter with said he-ne laser, said second mirror is disposed between said small focal length convex lens and said beam splitter, and said visible light photodetector is disposed adjacent to said beam splitter.

6. The device for real-time monitoring of airborne virus particles according to claim 5, wherein the shearing interference detection module comprises a first convex lens, a second convex lens, a third reflector, a grating, a high-precision piezoelectric actuator and a collection module, the second convex lens is disposed in parallel with the first convex lens and the sample tube, respectively, and is located between the first convex lens and the sample tube, the third reflector is disposed on a side of the second convex lens away from the first convex lens, the grating is disposed between the third reflector and the collection module, and the high-precision piezoelectric actuator is disposed on a side of the grating.

7. The device for real-time monitoring of airborne virus particles according to claim 6, wherein the control and data processing module comprises a movable mirror position calculating sub-module, a displacement control sub-module, an air pump control sub-module and a data processing sub-module, the movable mirror position calculating sub-module is electrically connected to the visible light photodetector, the displacement control sub-module is electrically connected to the voice coil motor, the displacement control sub-module is further electrically connected to the high precision piezoelectric actuator, the air pump control sub-module is electrically connected to the air pump, and the data processing sub-module is in signal connection with the collection module.