An adjustable multi-light source particle light scattering characteristics experimental device and method

Abstract

The present invention discloses an adjustable multi-light source particle light scattering characteristic experimental device and method, including a detachable laser, an incident light path, a scattered light path, a photodetector, a spherical scattering cavity, an optical power meter, an oscilloscope, a steam generator, a dust generator and an optical camera; the incident light path and the scattered light path can be slidably installed on a circular slide rail, so that the laser, the incident light path and the scattered light path can be rotated around the spherical scattering cavity for one circle and adjusted at any angle. It can realize multi-light source multi-angle laser incidence and multi-angle detector detection, and explore the particle scattering characteristics under the dynamic change of light source and angle; obtain the scattered light power signal of the particles in the sample to be tested at several scattering angles and different humidity through the optical power meter, and establish the functional relationship between the scattered light power and the output voltage; use the optical camera to directly shoot the particle scattering situation, and obtain the particle scattering information in various samples to be tested.

Description

Technical Field

[0001] The present invention relates to the technical field of particle light scattering property detection, and in particular to an adjustable multi-light source particle light scattering property experimental device and method. Background Art

[0002] With the development of society, dust concentration monitoring instruments have developed rapidly. The main methods include light scattering, gravity sedimentation, beta ray, weighing and electrostatic induction. Among them, the most widely used is the light scattering method, which generates scattered light by irradiating dust particles with lasers, and detects the intensity of the scattered light to calculate the dust concentration. In modern environmental monitoring and particle physics research, the light scattering properties of particulate matter are a key research area. The light scattering properties provide important information about the size, shape, composition and optical properties of particles, which are of great significance for understanding particulate matter in the atmosphere and water bodies, as well as cells and microparticles in the biomedical field. Traditional light scattering experimental systems usually only use one type of light source to illuminate particles for scattering experiments, or the optical configuration is relatively fixed, and the angles between light sources, between light sources and detectors, and between detectors, as well as the distance between optical elements, cannot be adjusted. In the process of measuring particles of different particle sizes or different material compositions, these limitations may lead to difficulties such as inaccurate or incomplete measurements. Summary of the invention

[0003] In view of the defects of the above-mentioned prior art, the technical problem to be solved by the present invention is to provide an adjustable multi-light source particle light scattering characteristics experimental device and method, which can perform multi-light source multi-angle laser incidence and multi-angle detector detection on particles of different particle sizes or different material compositions.

[0004] In order to solve the above technical problems, the present invention adopts the following technical solutions: an adjustable multi-light source particle light scattering characteristic experimental device, comprising a detachable laser, an incident light path, a scattered light path, a photoelectric detector, a spherical scattering cavity, an optical power meter, an oscilloscope, a steam generator, a dust generator and an optical camera, wherein the incident light path is provided with at least one, and the number of lasers corresponds to the incident light path; the incident light path and the scattered light path are both arranged on corresponding support foot kits through optical brackets, and the support foot kits can be slidably mounted on a circular slide rail, so that the laser, the incident light path and the scattered light path can be rotated around the spherical scattering cavity for one circle and adjusted at any angle; the output end of the scattered light path can be replaced with a probe or a photoelectric detector of an optical power meter, and the photoelectric detector is used to convert the optical power signal into a voltage signal, and output the converted voltage signal through the oscilloscope; the dust generator is used to provide dust for scattering with the incident laser, and the steam generator is used to create different humidity environments; the optical camera is respectively aimed at the incident light path and the scattered light path to take pictures.

[0005] Preferably, the incident light path is provided with an optical fiber interface, a collimating lens and a focusing lens in sequence along the laser path. The laser emitted by the laser enters the incident light path through the optical fiber interface and is converted into scattered light in the spherical scattering cavity and enters the scattered light path; the scattered light path is provided with an optical filter, a collimating lens, a focusing lens and an optical fiber interface in sequence along the scattered light path. The scattered light enters the photosensitive area of ​​the optical power meter probe through the optical fiber interface. The filter is used to avoid the interference of stray light on the scattering characteristics; the optical fiber interface connects the laser and the incident light path as well as the scattered light and the detector, respectively, to solve the problem that the light source and the path are difficult to be on the same level.

[0006] Preferably, the spherical scattering cavity is provided with a horizontal incision along the middle to divide it into two hemispheres, and a circular track is installed inside the edge of the incision, and at least one double-head sliding bracket is used as a support connection between the two hemispheres, so that a 3mm scattering cavity gap is left on the middle surface of the spherical scattering cavity; the positions of all supporting points can be adjusted according to the changes in the optical path to avoid interfering with the optical path, and they can be moved to an angle area that is not temporarily used in the experiment, so as to realize the measurement of all scattering angles of particle scattering.

[0007] Preferably, the steam and dust particles generated by the steam generator and the dust generator enter the spherical scattering cavity through an air pump to be scattered by the incident laser, and auxiliary air extraction is performed by an air compressor to achieve the stability of dust circulation.

[0008] Preferably, the spherical scattering cavity is provided with an internal dust passage and uses dry N2 as a protective gas to prevent dust from diffusing and contaminating the detection cavity.

[0009] Preferably, the slide rail is fixedly mounted on the honeycomb breadboard, which can effectively resist the influence of external vibration and impact, and ensure the stable operation of the experimental equipment.

[0010] Preferably, the particle light scattering characteristics experimental device also includes a blackout curtain to reduce the influence of external light on the experiment; the oscilloscope is provided with six channels, which can be connected to six photodetectors at the same time to simultaneously detect the electrical signals converted from six scattering angles.

[0011] Preferably, the incident light path and the scattered light path are both coated with organic dyes, and a light trap is provided 5 cm behind the spherical scattering cavity, facing each incident light path. The bottom of the light trap is installed by a double-headed screw and is in the same line as the incident laser, so as to absorb the scattered incident light.

[0012] An adjustable multi-light source particle light scattering characteristic experimental method uses an adjustable multi-light source particle light scattering characteristic experimental device, and the steps are as follows:

[0013] Step 1: Start the laser to emit incident laser, which is introduced into the laser path through the optical fiber interface. The laser passes through the collimating lens to become a collimated beam, which is focused by the focusing lens to improve the utilization rate of the beam and then injected into the spherical scattering cavity;

[0014] Step 2: Use a steam generator to create a humidity environment, and use a dust generator to provide dust particles. The dust particles and steam with the required humidity are introduced into the spherical scattering cavity to scatter with the incident laser, and the incident laser is converted into scattered light.

[0015] Step 3: After the scattered light is emitted from the spherical scattering cavity, it enters the scattered light path. The scattered light is first filtered out by a filter to remove stray light, then passes through a collimating lens to turn it into a collimated light beam, and finally passes through a focusing lens to focus the light beam and inject it into the photosensitive area of ​​the optical power meter to obtain the scattered light power signal of the particles in the sample to be tested at several scattering angles;

[0016] Step 4: Replace the optical power meter with a photodetector, convert the optical power signal into a voltage signal, and use an oscilloscope to output the converted voltage signal;

[0017] Step 5: Adjust the optical bracket to drive the incident light path and the scattered light path to rotate around the spherical scattering cavity to measure the scattered light characteristics at different angles, and use a steam generator to create different humidity environments to study the light scattering characteristics of particles under different humidity environments;

[0018] Step 6. Compare the scattered light power signal, voltage signal and dust mass concentration to obtain the linear relationship between the dust mass concentration and the voltage signal. Directly use an optical camera to photograph the particle scattering, output the photographed images with the supporting software, and analyze the scattering conditions of different particles.

[0019] Preferably, in step one, the laser wavelength is continuously and dynamically adjusted by software-controlled grating spectrometer for spectrometry, or lasers of different wavelengths and powers are directly replaced on the optical bracket to select light sources of multiple wavelengths, covering the spectrum from ultraviolet to infrared.

[0020] Beneficial effects of the present invention:

[0021] 1) By slidably mounting the incident light path and the scattered light path on a circular slide rail, the angle between the light sources can be adjusted by rotating around the spherical scattering cavity, which is convenient for measuring the scattered light characteristics at different angles and realizing 360° dynamic adjustment of the incident laser and the receiving scattering angle;

[0022] 2) The number of incident light paths is determined experimentally, which can be used to explore the scattering characteristics of particles under multi-laser and multi-angle irradiation, or to achieve characteristic detection of particles irradiated by a single laser;

[0023] 3) Use a steam generator to adjust different humidity environments to simulate different humidity application environments. At the same time, use a dust generator to experimentally study the scattering characteristics of particles with different particle sizes and compositions under different humidity environments;

[0024] 4) Using optical power meters, photodetectors, oscilloscopes, optical cameras and other equipment, it is possible to comprehensively collect and analyze the power signal and voltage signal of scattered light and the real-time scattering of particles, and provide multi-dimensional and multi-angle information on the scattering characteristics of particles;

[0025] 5) All parts of the experimental device can be disassembled and replaced, which improves its applicability and convenience. The configuration of multiple light sources and multiple angles will make the measurement of the light scattering characteristics of different particles more detailed and comprehensive. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is the assembly diagram of the experimental system for light scattering characteristics of particles;

[0027] Figure 2 It is a front view of the particle scattering detection structure;

[0028] Figure 3 is a side view of the particle scattering detection structure;

[0029] Figure 4 It is a top view of the particle scattering detection structure;

[0030] Figure 5 It is a schematic diagram of the structure of a spherical scattering cavity;

[0031] Figure 6 It is a flow chart of the basic experimental device invented;

[0032] In the figure: 1-honeycomb breadboard, 2-slide rail, 3-support foot kit a, 4-laser a, 5-collimating lens a, 6-optical fiber interface a, 7-focusing lens a, 8-focusing lens b, 9-collimating lens b, 10-optical fiber interface b, 11-laser b, 12-support foot kit b, 13-optical filter, 14-collimating lens c, 15-focusing lens c, 16-photoelectric detector, 17-support foot kit c, 18-spherical scattering cavity, 18a-circular track, 18b-double-head sliding bracket, 19-scattering cavity air inlet, 20-light trap a, 21-light trap b, 22-optical bracket a, 23-optical bracket b, 24-scattering cavity gap, 25-optical bracket c, 26-optical bracket d, 27-optical power meter, 28-oscilloscope, 29-air compressor, 30-air pump, 31-steam generator, 32-dust generator, 33-shading curtain. DETAILED DESCRIPTION

[0033] In order to better understand the improvements made by the present invention relative to the prior art, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0034] like Figure 1 As shown, an adjustable multi-light source particle light scattering characteristic experimental device is mainly composed of a detachable laser, an incident light path, a scattered light path, a photodetector 16, a spherical scattering cavity 18, an optical power meter 27, an oscilloscope 28, a steam generator 31, a dust generator 32 and an optical camera. In order to reduce the influence of external light on the experiment, the experimental device is also provided with a blackout curtain 33. There is at least one incident light path, and the number of lasers corresponds to the incident light path.

[0035] like Figure 2 As shown in FIG. 4 , the incident light path and the scattered light path are both set on the corresponding support foot kit through an optical bracket, and the support foot kit can be slidably mounted on the circular slide rail 2, so that the laser, the incident light path and the scattered light path can be adjusted at any angle by rotating around the spherical scattering cavity 18, which is convenient for measuring the scattered light characteristics at different angles. The slide rail 2 is fixedly mounted on the honeycomb breadboard 1. The honeycomb breadboard 1 is used as an optical experimental platform, which can effectively resist the influence of external vibration and impact, and ensure the stable operation of the experimental equipment.

[0036] like Figure 5 As shown, the spherical scattering cavity 18 is provided with a horizontal cut along the middle to divide it into two hemispheres, and a circular track 18a is installed inside the edge of the cut, and at least one double-headed sliding bracket 18b is used as a support connection for the two hemispheres, so that a 3mm scattering cavity gap 24 is left on the middle surface of the spherical scattering cavity 18, and the scattering cavity gap 24 is used to collect the incident laser, the incident dust and the dust scattered light. At the same time, the positions of all supporting points can be adjusted according to the changes in the optical path to avoid interfering with the optical path, and they can be moved to the angle area that is not used temporarily in the experiment to achieve the measurement of all scattering angles of particle scattering. The spherical scattering cavity 18 is mainly composed of four parts: a scattering cavity air inlet 19, a protective gas structure, a spherical cavity and a scattering cavity air outlet. The scattering cavity air inlet 19 and the scattering cavity air outlet are cylindrical passages with a diameter of 1.5cm, and the internal dust passage uses dry N2 as a protective gas.

[0037] When there are two incident light paths, the scattering characteristics of particles under multi-laser multi-angle irradiation are explored. The first incident light path is provided with a fiber interface a 6, a collimating lens a 5 and a focusing lens a 7 in sequence along the laser path. The laser emitted by the laser a 4 enters the first incident light path through the fiber interface a 6. The second incident light path is provided with a fiber interface b 10, a collimating lens b 9 and a focusing lens b 8 in sequence along the laser path. The laser emitted by the laser b 11 enters the second incident light path through the fiber interface b 10. The lasers of the two incident light paths are converted into scattered light in the spherical scattering cavity 18 and enter the scattered light path. And when there is one incident light path, the characteristic detection of particles irradiated by a single laser can be realized.

[0038] At least one scattered light path is provided, and a filter 13, a collimating lens c 14, a focusing lens c 15 and an optical fiber interface c are sequentially provided along the scattered light path. The scattered light enters the photosensitive area of ​​the optical power meter 27 probe through the optical fiber interface c. The filter 13 is provided to prevent the stray light from interfering with the scattering characteristics. The output end of the scattered light path can be replaced with a probe or a photodetector 16 of the optical power meter 27. The photodetector 16 is used to convert the optical power signal into a voltage signal and output the converted voltage signal through the oscilloscope 28. The oscilloscope 28 is provided with six channels, so six photodetectors can be connected at the same time to detect the electrical signals converted from six scattering angles at the same time.

[0039] The optical fiber interface group connects the laser and incident light path and the scattered light and detector respectively to solve the problem that the light source and the path are difficult to be on the same horizontal line. At the same time, the incident light path and the scattered light path are coated with organic dyes. The two incident light paths and one scattered light path are respectively installed on the corresponding optical bracket a 22, optical bracket b 23 and optical bracket d26, and the optical camera is installed on the optical bracket c 25. A light trap is set at 5 cm behind the spherical scattering cavity 18, facing each incident light path. The bottom of the light trap is installed by a double-headed screw and is in the same line with the incident laser, which is used to absorb the incident light that has been scattered. The first incident light path corresponds to the light trap b 21, and the second incident light path corresponds to the light trap a 20.

[0040] The dust generator 32 is used to provide dust to scatter with the incident laser, and the steam generator 31 is used to create different humidity environments. The steam and dust particles generated by the steam generator 31 and the dust generator 32 enter the spherical scattering cavity 18 through the air compressor 29 and the air pump 30 to scatter with the incident laser, and the air compressor 29 is used to assist in exhausting to achieve the stability of dust circulation. The experimental device is also equipped with an optical camera to take pictures of the incident light path and the scattered light path respectively. The optical camera directly takes pictures of the scattering of particles and obtains the scattering information of particles at different scattering angles or different humidity in various samples to be tested.

[0041] like Figure 6 As shown, an adjustable multi-light source particle light scattering characteristic experimental method is used, using the above experimental device, and the specific steps are as follows:

[0042] Step 1: Start the laser to emit incident laser, and the corresponding incident laser is introduced into the laser path through the respective optical fiber interfaces. The laser passes through the collimating lens to become a collimated beam, and the beam is focused by the focusing lens to improve the utilization rate of the beam and then injected into the spherical scattering cavity 18. The continuous dynamic adjustment of the laser wavelength can be controlled by software to split the grating spectrometer, or directly replace lasers of different wavelengths and powers on the optical bracket, and the filters, collimating lenses and focusing lenses with different parameters can be disassembled and replaced according to the situation.

[0043] Step 2: Use the steam generator 31 to create a humidity environment, study the light scattering characteristics of particulate matter under different humidity environments, and provide dust particles from the dust generator 32. The dust particles and steam with the required humidity are introduced into the spherical scattering cavity 18 to scatter with the incident laser, and the incident laser is converted into scattered light.

[0044] Step 3: After the scattered light is emitted from the spherical scattering cavity 18, it enters the scattered light path. The scattered light is first filtered out by a filter to remove stray light, then passes through a collimating lens to turn it into a collimated light beam, and finally passes through a focusing lens to focus the light beam and inject it into the photosensitive area of ​​the optical power meter 27 to obtain the scattered light power signal of the particles in the sample to be tested at several scattering angles.

[0045] Step 4: Replace the optical power meter 27 with a photodetector, convert the optical power signal into a voltage signal, and use an oscilloscope 28 to output the converted voltage signal. The use of a more sensitive Tektronix oscilloscope and a Sorebo optical power meter can better capture the scattered signal.

[0046] Step 5: Adjust the optical bracket to drive the incident light path and the scattered light path to rotate around the spherical scattering cavity 18, adjust the angles between the lasers, the angles between the detectors, and the angles between the laser and the detector to measure the scattered light characteristics at different angles, and use the steam generator 31 to create different humidity environments to study the light scattering characteristics of particulate matter under different humidity environments. The laser path body can be removably installed with collimating and focusing lenses of different parameters.

[0047] Step 6: According to the comparison of scattered light power signal, voltage signal and dust mass concentration, the linear relationship between dust mass concentration and voltage signal is obtained, and the scattered light power signal of particles in the sample to be tested at several scattering angles and different humidity is obtained. The photodetector converts the light power signal into an electrical signal, connects to an oscilloscope, and converts the oscilloscope output into an electrical signal. The voltage signal and scattered light power signal are compared to establish a functional relationship between scattered light power and output voltage. Directly use an optical camera to shoot the scattering of particles, obtain the scattering information of particles at different scattering angles or different humidity in various samples to be tested, and use the supporting software to output the pictures taken, and analyze the scattering of different particles.

[0048] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. An adjustable multi-light source particle light scattering characteristics experimental device, characterized by: The invention comprises a detachable laser, an incident light path, a scattered light path, a photodetector (16), a spherical scattering cavity (18), an optical power meter (27), an oscilloscope (28), a steam generator (31), a dust generator (32) and an optical camera. The incident light path is provided with a plurality of lasers, and the number of lasers corresponds to the number of incident light paths. The incident light path and the scattered light path are both provided on corresponding support foot kits through optical brackets, and the support foot kits are slidably mounted on a circular slide rail (2), so that the laser, the incident light path and The scattered light path can be rotated around the spherical scattering cavity (18) to adjust to any angle; the output end of the scattered light path can be replaced with a probe or a photoelectric detector (16) for installing an optical power meter (27); the photoelectric detector (16) is used to convert the optical power signal into a voltage signal and output the converted voltage signal through an oscilloscope (28); the dust generator (32) is used to provide dust for scattering with the incident laser, and the steam generator (31) is used to create different humidity environments; the optical camera is respectively aimed at the incident light path and the scattered light path to take pictures; The spherical scattering cavity (18) is provided with a horizontal cut along the middle thereof to divide it into two hemispheres, and a circular track (18a) is installed inside the edge of the cut, and a plurality of double-headed sliding brackets (18b) are used as support connections for the two hemispheres, so that a gap of 3 mm is left on the middle surface of the spherical scattering cavity (18); the positions of all support points can be adjusted according to changes in the optical path to avoid interference with the optical path; The steam and dust particles generated by the steam generator (31) and the dust generator (32) enter the spherical scattering cavity (18) through the air pump (30) to be scattered by the incident laser, and auxiliary air extraction is performed through the air compressor (29) to achieve the stability of dust circulation; The particle light scattering property experimental device also includes a light shielding curtain (33) to reduce the influence of external light on the experiment; the oscilloscope (28) is provided with six channels, which can be connected to six photoelectric detectors at the same time to simultaneously detect the electrical signals converted from six scattering angles.

2. The adjustable multi-light source particle light scattering characteristic experimental device according to claim 1, characterized in that: The incident light path is provided with an optical fiber interface, a collimating lens and a focusing lens in sequence along the laser path; the laser light emitted by the laser enters the incident light path through the optical fiber interface and is converted into scattered light in the spherical scattering cavity (18) and enters the scattered light path; the scattered light path is provided with an optical filter, a collimating lens, a focusing lens and an optical fiber interface in sequence along the scattered light path; the scattered light enters the photosensitive area of ​​the optical power meter (27) probe through the optical fiber interface.

3. The adjustable multi-light source particle light scattering characteristic experimental device according to claim 1, characterized in that: The spherical scattering cavity (18) is provided with an internal dust passage and uses dry N2 as a protective gas.

4. The adjustable multi-light source particle light scattering characteristic experimental device according to claim 1, characterized in that: The slide rail (2) is fixedly mounted on the honeycomb breadboard (1).

5. The adjustable multi-light source particle light scattering characteristic experimental device according to claim 1, characterized in that: The incident light path and the scattered light path are both coated with organic dyes, and a light trap is provided 5 cm behind the spherical scattering cavity (18) directly opposite each incident light path. The bottom of the light trap is installed by means of double-headed screws and is in the same straight line as the incident laser, and is used to absorb the scattered incident light.

6. An adjustable multi-light source particle light scattering characteristics experimental method, characterized in that: The adjustable multi-light source particle light scattering characteristic experimental device according to any one of claims 1 to 5 is used, and the steps are as follows: Step 1, start the laser to emit incident laser, the incident laser is introduced into the laser path through the optical fiber interface, the laser passes through the collimating lens to turn it into a collimated beam, the beam is focused by the focusing lens to improve the utilization rate of the beam and then injected into the spherical scattering cavity (18); Step 2: using a steam generator (31) to create a humidity environment, and using a dust generator (32) to provide dust particles, and providing dust particles and steam with a required humidity to pass into the spherical scattering cavity (18), where they are scattered by incident laser light, and the incident laser light is converted into scattered light; Step 3, after the scattered light is emitted from the spherical scattering cavity (18), it enters the scattered light path, the scattered light is first filtered out by a filter to remove stray light, then passes through a collimating lens to convert it into a collimated light beam, and finally passes through a focusing lens to focus the light beam and emit it into the photosensitive area of ​​an optical power meter (27), thereby obtaining scattered light power signals of particles in the sample to be tested at several scattering angles; Step 4: Replace the optical power meter (27) with a photodetector, convert the optical power signal into a voltage signal, and use an oscilloscope (28) to output the converted voltage signal; Step 5: adjusting the optical bracket to drive the incident light path and the scattered light path to rotate around the spherical scattering cavity (18) to measure the scattered light characteristics at different angles, and using a steam generator (31) to create different humidity environments to study the light scattering characteristics of particles under different humidity environments; Step 6. Compare the scattered light power signal, voltage signal and dust mass concentration to obtain the linear relationship between the dust mass concentration and the voltage signal. Directly use an optical camera to photograph the particle scattering, output the photographed images with the supporting software, and analyze the scattering conditions of different particles.

7. The adjustable multi-light source particle light scattering property experimental method according to claim 6, characterized in that: In step one, the laser wavelength is continuously and dynamically adjusted by software-controlled grating spectrometer for light splitting, or lasers of different wavelengths and powers are directly replaced on the optical bracket.

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