A liquid concentration measurement system and method

Abstract

The present invention discloses a liquid concentration measurement system and method. The liquid concentration measurement system includes a light source module, a beam splitting module, a container, a first reflection module, a second reflection module, a detection and reception module, a rotation measurement module, and a processing module. The beam splitting module is located on the propagation path of the detection beam and is used to split the detection beam to form a first detection beam and a second detection beam. The container is used to hold the liquid to be detected and is located on the propagation path of the first detection beam. The rotation measurement module is electrically connected to the processing module and is connected to the container. The processing module is electrically connected to the detection and reception module. The above technical solution utilizes the interference of light to obtain the corresponding relationship between the liquid to be detected with different concentrations and the change amount of the interference image. In this way, only by relying on the processing module and the change amount of the interference image, the concentration of the liquid to be detected can be determined, making the system have a wide application range, high precision and low cost.

Description

Technical Field

[0001] The present invention relates to the technical field of liquid concentration measurement, and particularly to a liquid concentration measurement system and method. Background Art

[0002] Concentration is one of the important indicators of a solution and is essential in scientific research, production, and daily life. There are various methods for measuring the concentration of a liquid.

[0003] In traditional measurement methods, such as Abbe refractometers, polarimeters, and ultrasonic grating methods. Among them, the Abbe refractometer is mainly used for sugar solutions and cannot be used to measure acid-base corrosive solutions. Moreover, its measurement range is limited. If the refractive index of the sample to be tested is not within the range of 1.3 - 1.7, the Abbe refractometer cannot measure it, and it has great limitations; when measuring with a polarimeter, it is only applicable to solutions with optical activity, and its application is limited; the ultrasonic grating method fits the relationship between the grating constant and the concentration, but the method accuracy varies with the type of solution and has a large error for some solutions.

[0004] Therefore, there is an urgent need for a liquid concentration measurement system and method with a wide application range and high accuracy. Summary of the Invention

[0005] Embodiments of the present invention provide a liquid concentration measurement system and method, which utilize the interference of light to have a wider application range, simpler operation, higher precision, better reproducibility, and lower cost.

[0006] In a first aspect, embodiments of the present invention provide a liquid concentration measurement system, including a light source module, a beam splitting module, a container, a first reflection module, a second reflection module, a detection and reception module, a rotation measurement module, and a processing module;

[0007] The light source module is used to emit a detection beam;

[0008] The beam splitting module is located on the propagation path of the detection beam and is used to split the detection beam into a first detection beam and a second detection beam;

[0009] The container is used to hold the liquid to be detected, and the container is located on the propagation path of the first detection beam; the first detection beam is incident on the detection and reception module after passing through the liquid to be detected, being reflected by the first reflection module, and transmitted by the beam splitting module; the second detection beam is incident on the detection and reception module after being reflected by the second reflection module and reflected by the beam splitting module;

[0010] The rotation measurement module is electrically connected to the processing module and is connected to the container, and is used to drive the container to rotate according to the processing instruction output by the processing module to adjust the optical path of the first detection beam passing through the liquid to be detected;

[0011] The processing module is electrically connected to the detection and receiving module, and is configured to determine the concentration of the liquid to be detected according to the interference image in the detection and receiving module.

[0012] Furthermore, the liquid concentration measurement system further includes a compensation module; the compensation module is located in the optical path between the beam splitting module and the second reflection module, and is configured to adjust the optical path of the second detection beam.

[0013] Furthermore, the beam splitting module is arranged in parallel with the compensation module and intersects with the light output direction of the light source module; the inclination direction of the beam splitting module and the compensation module forms a 45° angle with the light output direction of the light source module.

[0014] Furthermore, the rotation measurement module includes a micrometer device, a motor device, a linkage rod, and a rotation device;

[0015] The micrometer device includes a knob and a micrometer head, the motor device includes a rotating shaft, the knob is engaged with the rotating shaft, the micrometer head is fixed to one side of the linkage rod, and the other side of the linkage rod is fixed to the surface of the container; the rotation device is fixed in the optical path between the first reflection module and the beam splitting module, and the rotation device includes a rotating shaft, and the container is fixed on the rotating shaft.

[0016] Furthermore, the first reflection module and / or the second reflection module is rotatable;

[0017] The processing module is electrically connected to the rotatable first reflection module and / or the second reflection module, and is configured to control the rotation angle of the first reflection module and / or the second reflection module so that the first detection beam and the second detection beam coincide to form an interference image.

[0018] Furthermore, the light source module includes a light source output unit and a beam expanding unit;

[0019] The light source output unit is configured to output a laser beam;

[0020] The beam expanding unit is located on the propagation path of the laser beam and is configured to expand the laser beam to form the detection beam.

[0021] Furthermore, the detection and receiving module includes a receiving and imaging unit and an observation unit;

[0022] The receiving and imaging unit is located in the optical path between the beam splitting module and the observation unit, and is configured to receive the first detection beam and the second detection beam and form an image;

[0023] The observation unit is configured to collect the interference image of the first detection beam and the second detection beam and feed it back to the processing module.

[0024] Further, the beam splitting module includes a beam splitting plate;

[0025] The beam splitting plate includes a beam splitting plate body and a semi-transmissive and semi-reflective film disposed on the surface of the beam splitting plate body.

[0026] Further, the liquid concentration measurement system further includes a thermostat; the light source module, the beam splitting module, the container, the first reflection module, the second reflection module, the detection and receiving module, and the rotation measurement module are all located inside the thermostat.

[0027] In a second aspect, an embodiment of the present invention further provides a liquid concentration measurement method, which is applied to any of the above liquid concentration measurement methods. The liquid concentration measurement method includes:

[0028] Adjust the rotation measurement module to determine the deflection angle of the container;

[0029] Obtain an interference image;

[0030] Repeat the above steps to obtain the change amount of the interference image of the liquid to be detected with different concentrations at the same deflection angle;

[0031] According to the change amount of the interference image corresponding to the liquid to be detected with different concentrations at the same deflection angle, obtain the corresponding relationship between the solution concentration and the change amount of the interference image;

[0032] According to the corresponding relationship, determine the concentration of the liquid to be detected.

[0033] In the liquid concentration measurement system of the present invention, it includes a light source module, a beam splitting module, a container, a first reflection module, a second reflection module, a detection and reception module, a rotation measurement module, and a processing module. Among them, the light source module is used to emit a detection light beam. The beam splitting module is located on the propagation path of the detection light beam and is used to split the detection light beam into a first detection light beam and a second detection light beam. The container is used to hold the liquid to be detected, and the container is located on the propagation path of the first detection light beam. The first detection light beam is incident on the detection and reception module after passing through the liquid to be detected, being reflected by the first reflection module, and transmitted by the beam splitting module. The second detection light beam is incident on the detection and reception module after being reflected by the second reflection module and reflected by the beam splitting module. The rotation measurement module is electrically connected to the processing module and is connected to the container, and is used to drive the container to rotate according to the processing instruction output by the processing module to adjust the optical path of the first detection light beam passing through the liquid to be detected. In the above technical solution, through the good correlation between the concentration and refractive index of the liquid to be detected, and then using the interference of light, the corresponding relationship between the liquid to be detected with different concentrations and the change amount of the interference image is obtained through the above system. In this way, the processing module only needs to determine the concentration of the liquid to be detected according to this corresponding relationship and the interference image in the detection and reception module, thereby reducing the errors and uncertainties brought by the calculation, simplifying the steps, and having fewer required modules, simple operation, low cost, simple assembly, good reproducibility, and high precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 is a specific structural diagram of a liquid concentration measurement system provided by an embodiment of the present invention;

[0035] Figure 2 is a flowchart of a liquid concentration measurement method provided by an embodiment of the present invention;

[0036] Figure 3 is a corresponding relationship diagram between the concentration of sodium chloride liquid and the change amount of the interference image provided by an embodiment of the present invention;

[0037] Figure 4 is a corresponding relationship diagram between the concentration of calcium chloride liquid and the change amount of the interference image provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will, in combination with the accompanying drawings in the embodiments of the present invention, completely describe the technical solutions of the present invention through specific implementation manners. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts shall fall within the protection scope of the present invention.

[0039] It should be noted that the terms "first", "second", etc. in the description, claims and above-mentioned drawings of the present invention are used to distinguish similar objects and do not necessarily describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily limit to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0040] Figure 1 is a specific structural diagram of a liquid concentration measurement system provided by an embodiment of the present invention. Refer to Figure 1 As shown in the figure, the liquid concentration measurement system 1 includes a light source module 10, a beam splitting module 20, a container 30, a first reflection module 41, a second reflection module 42, a detection and receiving module 50, a rotation measurement module 60, and a processing module 70. The light source module 10 is used to emit a detection beam. The beam splitting module 20 is located on the propagation path of the detection beam and is used to split the detection beam into a first detection beam and a second detection beam. The container 30 is used to hold the liquid to be detected, and the container 30 is located on the propagation path of the first detection beam. The first detection beam is incident on the detection and receiving module 50 after passing through the liquid to be detected, being reflected by the first reflection module 41 and transmitted by the beam splitting module 20. The second detection beam is incident on the detection and receiving module 50 after being reflected by the second reflection module 42 and reflected by the beam splitting module 20. The rotation measurement module 60 is electrically connected to the processing module 70 and is connected to the container 30, and is used to drive the container 30 to rotate according to the processing instruction output by the processing module 70 to adjust the optical path of the first detection beam passing through the liquid to be detected. The processing module 70 is electrically connected to the detection and receiving module 50 and is used to determine the concentration of the liquid to be detected according to the interference image in the detection and receiving module 50.

[0041] Specifically, as shown in Figure 1As shown in the figure, the detection beam emitted by the light source module 10 forms a first detection beam and a second detection beam with different directions after being split by the beam splitting module 20. Among them, the first detection beam is formed by reflection when the detection beam passes through the beam splitting module 20 for the first time. Then, the first detection beam passes through the container 30, reaches the first reflection module 41, is reflected by the first reflection module 41, passes through the container 30 again, then passes through the beam splitting module 20 by transmission, and is incident on the detection and receiving module 50, thus forming a spot of light on the detection and receiving module 50. The second detection beam is formed by transmission when the detection beam passes through the beam splitting module 20 for the first time. Then, after the second detection beam reaches the second reflection module 42, it is reflected by the second reflection module 42, then reflected by the beam splitting module 20, and is incident on the detection and receiving module 50, thus forming another spot of light on the detection and receiving module 50. In this way, by adjusting the position and height of the first reflection module 41 or the second reflection module 42, the two spots of light formed on the detection and receiving module 50 can be made to coincide, so that an interference image can be observed subsequently. Among them, the interference image can be interference fringes.

[0042] It can be understood that when the detection beam emitted by the light source module 10 is a single beam of light, two spots of light are formed on the detection and receiving module 50 by the liquid concentration measurement system 1. At this time, it is convenient to adjust the two spots of light to coincide. When the detection beam emitted by the light source module 10 is multiple beams of light, the two coincident spots of light become interference fringes. That is, because the frequencies of the two beams of light are equal, the vibration directions are the same, and the phase difference is constant, an interference phenomenon occurs after reaching the detection and receiving module 50, resulting in interference fringes.

[0043] In addition, the container 30 can be a transparent cuvette containing the liquid to be detected. In the initial state, the position of the container 30 is set parallel to the first reflection module 41. When the position of the container 30 changes, the optical path of the first detection beam passing through the liquid to be detected also changes accordingly. As a result, the throughput of the interference fringes can be observed on the detection and reception module 50. That is, when the position of the container 30 changes, the number of interference images also changes. Then, by setting the rotation measurement module 60 to be electrically connected to the processing module 70 and connected to the container 30, under the processing instruction output by the processing module 70, the rotation measurement module 60 drives the container 30 to rotate. Through the rotation of the container 30, the change amount of the interference images on the detection and reception module 50 can be observed. After experiments with multiple groups of liquids to be detected with different concentrations, the corresponding relationship between the concentration of the liquid to be detected and the change amount of the interference images can be obtained, generating a standard curve of the concentration of the liquid to be detected - change amount of the interference images and storing it in the processing module 70. The processing module 70 is electrically connected to the detection and reception module 50. After that, the processing module 70 only needs to determine the current concentration of the liquid to be detected according to the interference images in the detection and reception module 50 and the stored standard curve of the concentration of the liquid to be detected - change amount of the interference images. In this way, a functional relationship with the concentration of the liquid to be detected - change amount of the interference images is directly established through the data obtained from the experiment, thereby reducing the errors and uncertainties brought by calculations, improving the measurement accuracy, and having fewer required devices, a wide application range, simple operation, low cost, easy assembly, and good reproducibility.

[0044] It should be noted that a video recognition program for counting by sensing the change in the light intensity of the interference fringes is also set in the processing module 70. Thus, the light intensity when the interference fringes undergo throughput can be directly converted into numbers, which not only saves time and manpower but also makes the measurement of the fringe change amount more accurate, thereby further improving the measurement accuracy of the liquid concentration.

[0045] In summary, the liquid concentration measurement system in the embodiments of the present invention includes a light source module, a beam splitting module, a container, a first reflection module, a second reflection module, a detection and receiving module, a rotation measurement module, and a processing module. The light source module is used to emit a detection light beam. The beam splitting module is located on the propagation path of the detection light beam and is used to split the detection light beam into a first detection light beam and a second detection light beam. The container is used to hold the liquid to be detected, and the container is located on the propagation path of the first detection light beam. The first detection light beam is incident on the detection and receiving module after passing through the liquid to be detected, being reflected by the first reflection module, and being transmitted by the beam splitting module in sequence. The second detection light beam is incident on the detection and receiving module after being reflected by the second reflection module and being reflected by the beam splitting module in sequence. The rotation measurement module is electrically connected to the processing module and is connected to the container, and is used to drive the container to rotate according to the processing instruction output by the processing module to adjust the optical path of the first detection light beam passing through the liquid to be detected. In the above technical solution, through the good correlation between the concentration and refractive index of the liquid to be detected, and then using the interference of light, the corresponding relationship between the liquid to be detected with different concentrations and the change amount of the interference image is obtained through the above system. In this way, the processing module only needs to determine the concentration of the liquid to be detected according to this corresponding relationship and the interference image in the detection and receiving module, thereby reducing the errors and uncertainties brought by calculations, simplifying the steps, and having fewer required modules, simple operation, low cost, simple assembly, good reproducibility, and high accuracy.

[0046] Based on the above embodiments, refer to Figure 1 , the liquid concentration measurement system further includes a compensation module 80. The compensation module 80 is located in the optical path between the beam splitting module 20 and the second reflection module 42 and is used to adjust the optical path of the second detection light beam.

[0047] Specifically, as Figure 2 shown, since the container 30 is located on the propagation path of the first detection light beam, that is, the container 30 is located in the optical path between the beam splitting module 20 and the first reflection module 41. That is to say, compared with the propagation path of the second detection light beam, the propagation path of the first detection light beam has an additional optical path in the container 30. Therefore, the compensation module 80 is arranged in the optical path between the beam splitting module 20 and the second reflection module 42. After the detection light beam emitted by the light source module 10 passes through the beam splitting module 20 for the first time and is transmitted to form the second detection light beam, the second detection light beam first passes through the compensation module 80, reaches the second reflection module 42, is reflected by the second reflection module 42, passes through the compensation module 80 again, and then passes through the beam splitting module 20 and is transmitted, and is incident on the detection and receiving module 50. In this way, the optical path of the second detection light beam is adjusted by the compensation module 80, so that the propagation optical path of the first detection light beam is the same as that of the second detection light beam, that is, the experimental error is further reduced, the measurement result is more accurate, and the reliability of the liquid concentration measurement system is improved.

[0048] Optionally, continue to refer toFigure 1 The beam splitting module 20 and the compensation module 80 are arranged in parallel, intersect with the light output direction of the light source module 10, and the inclination directions of the beam splitting module 20 and the compensation module 80 form a 45° angle with the light output direction of the light source module 10.

[0049] Specifically, as Figure 1 shown, the beam splitting module 20 and the compensation module 80 are arranged in parallel. In this way, the transmission angle of the detection beam emitted by the light source module 10 when passing through the beam splitting module 20 for the first time and forming the second detection beam is the same as the transmission angle of the second detection beam when passing through the compensation module 80 for the first time. So that when the second detection beam is reflected by the second reflection module 42 and then passes through the compensation module 80 again, it can return to the beam splitting module 20 along the original path, ensuring the accuracy of the experiment. In addition, both the beam splitting module 20 and the compensation module 80 intersect with the light output direction of the light source module 10, and the inclination direction forms a 45° angle with the light output direction of the light source module 10. In this way, the detection beam emitted by the light source module 10 can be split into a first detection beam and a second detection beam that are perpendicular to each other when passing through the beam splitting module 20 for the first time, that is, the second detection beam is parallel to the light output direction of the light source module 10, and the first detection beam is perpendicular to the light output direction of the light source module 10, ensuring that the first detection beam and the second detection beam can form an interference phenomenon, avoiding the error caused by the deflection angle when the first detection beam and the second detection beam are not perpendicular, reducing the experimental error, making the measurement result more accurate, and improving the reliability of the liquid concentration measurement system.

[0050] It should be noted that after the beam splitting module 20 and the compensation module 80 are set to be parallel to each other and both intersect with the light output direction of the light source module 10 at 45°, the beam splitting module 20 and the compensation module 80 are fixed to avoid the angle change of the beam splitting module 20 and the compensation module 80 during the experiment, resulting in experimental error.

[0051] On the basis of the above embodiments, continue to refer to Figure 1 , the rotation measurement module 60 includes a micrometer device 61, a motor device 62, a linkage rod 63 and a rotation device 64. The micrometer device 61 includes a knob 611 and a micrometer head 612. The motor device 62 includes a rotating shaft 621. The knob 611 is engaged with the rotating shaft 621. The micrometer head 622 is fixed to one side of the linkage rod 63. The other side of the linkage rod 63 is fixed to the surface of the container 30. The rotation device 64 is fixed in the optical path between the first reflection module 41 and the beam splitting module 20. The rotation device 64 includes a rotating shaft 641. The container 30 is fixed on the rotating shaft 641.

[0052] Specifically, continue to refer to Figure 1, the rotation measurement module 60 includes a micrometer device 61. The micrometer device 61 can be a micrometer, also known as a vernier caliper, a micrometer gauge, or a screw gauge. It is a more precise tool for measuring length than a vernier caliper. It can measure length accurately to 0.01 mm and has a measurement range of several centimeters. It can not only achieve the purpose of controlling the rotation speed of the container 30 but also accurately control and record the starting and ending positions. The micrometer device 61 includes a knob 611 and a micrometer head 622. By rotating the knob 611, the micrometer head 622 is driven to move downward. Furthermore, by setting a motor device 62, the motor device 62 includes a rotating shaft 621. The edge of the rotating shaft 621 meshes with the edge of the knob 611. Thus, the rotation of the motor device 62 drives the rotation of the knob 611. The rotation measurement module 60 also includes a linkage rod 63 and a rotating device 64. The rotating device 64 is fixed in the optical path between the first reflection module 41 and the spectroscopic module 20. It is provided with a rotating shaft 641, that is, the rotating device 64 is fixed on the base, and both the rotating shaft 641 and the rotating device 64 remain fixed. A groove is provided at the bottom of the container 30. The groove of the container 30 is movably connected to the rotating shaft 641, so that the container 30 can rotate around the rotating shaft 641. Furthermore, both sides of the linkage rod 63 can be fixed to the micrometer head 622 and the surface of the container 30 respectively. The movement of the micrometer device 61 and the container 30 is linked through the linkage rod 63. That is, when the micrometer head 622 moves downward, the container 30 is driven to rotate clockwise through the linkage rod 63. In this way, by simply outputting a processing instruction from the processing module 70 to the motor device 62, the container 30 can be driven to rotate. On the one hand, it saves manpower, and on the other hand, the rotation of the container 30 is controlled through the linkage structure of the motor device 62 and the micrometer device 61, and the rotation speed control is more precise, avoiding errors caused by the fluctuation of the rotation speed of the container 30 during the measurement process. Furthermore, the experimental error is reduced, the measurement result is more accurate, and the reliability of the liquid concentration measurement system is improved.

[0053] It should be noted that Figure 1 In order to better illustrate the positional relationship of each module in the liquid concentration measurement system, the top view of the liquid concentration measurement system is shown. Furthermore, the downward movement of the micrometer head 622 described is based on this top view. Those skilled in the art can know that during the actual measurement process, the micrometer head 622 should move forward or backward.

[0054] Furthermore, continue to refer to Figure 1 , the first reflection module 41 and / or the second reflection module 42 can rotate. The processing module 70 is electrically connected to the rotatable first reflection module 41 and / or the second reflection module 42, and is used to control the rotation angle of the first reflection module 41 and / or the second reflection module 42, so that the first detection beam and the second detection beam coincide to form an interference image.

[0055] Specifically, during the measurement process of the liquid concentration measurement system, it is necessary to first adjust the position of the first reflection module 41 or the second reflection module 42 to make the two light spots formed on the detection and reception module 50 coincide, so as to be able to observe the interference image subsequently. Furthermore, the processing module 70 can be electrically connected to the first reflection module 41 and / or the second reflection module 42, and the rotation angle of the rotatable first reflection module 41 and / or the second reflection module 42 can be controlled through the processing module 70, so that the two light spots formed by the first detection light beam and the second detection light beam on the detection and reception module 50 coincide, which makes the control more convenient and the test results more accurate.

[0056] Optionally, referring to Figure 1 , the light source module 10 includes a light source emission unit 11 and a beam expansion unit 12. The light source emission unit 11 is used to emit a laser beam, and the beam expansion unit 12 is located on the propagation path of the laser beam and is used to expand the laser beam to form a detection light beam.

[0057] Specifically, the light source module 10 includes a light source emission unit 11 and a beam expansion unit 12. The laser beam emitted by the light source emission unit 11 is a single beam of light. When the light source module 10 emits a single beam of light, two light spots are formed on the detection and reception module 50 by the liquid concentration measurement 1 system. At this time, the interference image cannot be observed, but it is convenient to adjust the two light spots to coincide. When the light source module 10 emits multiple beams of light, the two coincident light spots become interference fringes. That is, because the frequencies of the two light beams are equal, the vibration directions are the same, and the phase difference is constant, interference occurs after reaching the detection and reception module 50, resulting in interference fringes. Therefore, during the measurement process, it is necessary to use the beam expansion unit 12 to expand and disperse the single beam of light emitted by the source emission unit 11 into multiple beams of light.

[0058] It should be noted that during the measurement process, in order to facilitate the adjustment of the images formed by the first detection light beam and the second detection light beam on the detection and reception module 50 to coincide, it is necessary to first move the beam expansion unit 12 away so that the light source module 10 emits a single beam of light. In this way, two light spots are formed on the detection and reception module 50, which is convenient for adjusting the two light spots to align and coincide. Then, the beam expansion unit 12 is moved back, and the single beam of light is expanded and dispersed into multiple beams of light by the beam expansion unit 12, and the interference image can be observed on the detection and reception module 50.

[0059] Optionally, continue to refer to Figure 1 , the detection and reception module 50 includes a reception imaging unit 51 and an observation unit 52. The reception imaging unit 51 is located in the optical path between the beam splitting module 20 and the observation unit 52 and is used to receive the first detection light beam and the second detection light beam and form an image. The observation unit 52 is used to collect the interference image of the first detection light beam and the second detection light beam and feed it back to the processing module 70.

[0060] Specifically, the receiving imaging unit 51 can be a ground glass receiving screen. The first detection beam passes through the container 30, reaches the first reflection module 41, is reflected by the first reflection module 41, passes through the container 30 again, then is transmitted through the beam splitting module 20, and is incident on the receiving imaging unit 51, thus forming an image on the receiving imaging unit 51. The second detection beam first passes through the compensation module 80, reaches the second reflection module 42, is reflected by the second reflection module 42, passes through the compensation module 80 again, then is transmitted through the beam splitting module 20, and is incident on the receiving imaging unit 51, thus forming an image on the receiving imaging unit 51. When adjusting the images formed by the first detection beam and the second detection beam on the receiving imaging unit 51 to coincide, and when the light source module 10 emits multiple beams of light, an interference image can be observed on the receiving imaging unit 51. During the rotation of the container 30, the interference image will change, that is, the interference fringes will expand and contract. Furthermore, the observation unit 52 is correspondingly arranged for the receiving imaging unit 51. The observation unit 52 can be a camera, which collects the interference image of the first detection beam and the second detection beam and feeds it back to the processing module 70. A video recognition program for counting by sensing the light intensity change of the interference fringes is set in the processing module 70. Furthermore, the light intensity when the interference fringes expand and contract can be directly converted into a number, that is, the video information collected in the observation unit 52 is converted into a specific number of the interference fringe change amount.

[0061] Optionally, continue to refer to Figure 1 The beam splitting module 20 includes a beam splitting plate 21, and the beam splitting plate 21 includes a beam splitting plate main body 211 and a semi-transparent and semi-reflective film 212 provided on the surface of the beam splitting plate main body 211.

[0062] Specifically, as Figure 1 shown, the beam splitting module 20 can be a beam splitting plate 21, and the beam splitting plate 21 includes a semi-transparent and semi-reflective film 212. By means of the semi-transparent and semi-reflective film 212, when the detection beam passes through the beam splitting module 20, a part of the beam is reflected to form the first detection beam, and the other part of the beam is transmitted to form the second detection beam. Exemplarily shown in the figure, the semi-transparent and semi-reflective film 212 is located on the surface of the beam splitting plate main body 211 close to the compensation module 80. In other embodiments, the semi-transparent and semi-reflective film 212 can also be located on the surface of the beam splitting plate main body 211 close to the light source module 10. The present invention does not limit this, and those skilled in the art can set it according to needs.

[0063] Optionally, continue to refer to Figure 1 The liquid concentration measurement system 1 further includes a constant temperature box 90, and the light source module 10, the beam splitting module 20, the container 30, the first reflection module 41, the second reflection module 42, the detection and receiving module 50, and the rotation measurement module 60 are all located inside the constant temperature box 90.

[0064] Specifically, as Figure 1As shown, since temperature has a certain impact on the concentration measurement of the liquid to be detected, the light source module 10, the beam splitting module 20, the container 30, the first reflection module 41, the second reflection module 42, the detection and reception module 50, the rotation measurement module 60, the processing module 70, and the compensation module 80 are all arranged in the constant temperature box 90 to avoid the influence of temperature on the final measurement structure, making the measurement result more accurate and improving the reliability of the liquid concentration measurement system.

[0065] Based on the same inventive concept, an embodiment of the present invention further provides a liquid concentration measurement method, which is applied to the above liquid concentration measurement system. Figure 2 It is a flowchart of a liquid concentration measurement method provided by an embodiment of the present invention. As Figure 1 and Figure 2 shown, the liquid concentration measurement method includes:

[0066] S110. Adjust the rotation measurement module to determine the deflection angle of the container.

[0067] Specifically, first, move the beam expanding unit away. By adjusting the rotation measurement module, the container is located at the initial position, that is, the container is parallel to the light emitting direction of the light source module. Then, the processing module controls the rotation angles of the rotatable first reflection module and / or the second reflection module so that the two light spots formed by the first detection light beam and the second detection light beam on the detection and reception module coincide. Then, turn the beam expanding unit back, and an interference image can be observed on the detection and reception module. Adjust the constant temperature box to keep the temperature constant. Then, the rotation measurement module drives the container to rotate through the processing instruction output by the processing module to adjust the optical path when the first detection light beam passes through the liquid to be detected in the container. As the container rotates, the optical path also changes, and it can be observed that the interference image slowly swallows and spits on the detection and reception module. Control the operation time of the motor device, read the advancing distance L of the micrometer device, and combine the distance r from the center of the rotating shaft in the rotating device to the inner side of the end of the micrometer head of the micrometer device, and the distance L2 from the center of the rotating shaft to the surface of the linkage rod, and substitute them into the formula to obtain the deflection angle θ of the container.

[0068] It should be noted that the deflection angle θ of the container is a fixed value during the measurement process. That is, after obtaining the deflection angle θ of the container, during the subsequent measurement process, it is necessary to ensure that the deflection angle θ remains unchanged.

[0069] S120. Obtain the interference image.

[0070] During the process of adjusting the rotation measurement module to determine the deflection angle of the container, the observation unit collects the change amount of the interference image and feeds the collected change amount of the interference image back to the processing module. A video recognition program that counts by sensing the change in the light intensity of the interference fringes is set in the processing module. Thus, the light intensity when the interference fringes expand and contract can be directly converted into a number, that is, the video information collected by the observation unit is converted into the specific number of the change amount of the interference image, and the corresponding relationship between the change amount of the interference image of the liquid to be detected at this concentration is obtained.

[0071] S130. Repeat the above steps to obtain the change amount of the interference image of the liquid to be detected at different concentrations under the same deflection angle.

[0072] Replace the liquid to be detected in the container and repeat steps S110 - S120 to obtain the change amount of the interference image of the liquid to be detected at different concentrations under the same deflection angle.

[0073] S140. According to the change amount of the interference image corresponding to the liquid to be detected at different concentrations under the same deflection angle, obtain the corresponding relationship between the solution concentration and the change amount of the interference image.

[0074] Specifically, summarize the change amount of the interference image of the liquid to be detected at different concentrations under the same deflection angle obtained in the above steps, as well as the liquid to be detected at different concentrations, establish the corresponding relationship between the concentration of the liquid to be detected - the change amount of the interference image, and store this corresponding relationship in the processing module.

[0075] S150. Determine the concentration of the corresponding liquid to be detected according to the corresponding relationship.

[0076] In this way, only by measuring the change amount of the interference image of the liquid to be detected by the liquid concentration measurement system, the concentration of the liquid to be detected can be obtained according to the corresponding relationship between the concentration of the liquid to be detected - the change amount of the interference image stored in the processing module.

[0077] In the liquid concentration measurement method of the present invention, by adjusting the rotation measurement module, the deflection angle of the container is determined, and an interference image is obtained. Then, the above steps are repeated to obtain the change amount of the interference images of the liquid to be detected with different concentrations at the same deflection angle. According to the change amount of the interference images corresponding to the liquid to be detected with different concentrations at the same deflection angle, the corresponding relationship between the solution concentration and the change amount of the interference image is obtained. According to this corresponding relationship, the concentration of the liquid to be detected is determined. In the above technical solution, due to the good correlation between the concentration of the liquid to be detected and the refractive index, and then by using the interference of light, the corresponding relationship between the liquid to be detected with different concentrations and the change amount of the interference image is obtained through the above system. In this way, the processing module only needs to determine the concentration of the liquid to be detected according to this corresponding relationship and the interference image in the measurement receiving module, thereby reducing the errors and uncertainties brought by calculations, simplifying the steps, and having fewer required modules, simple operation, low cost, simple assembly, good reproducibility, and high precision.

[0078] Specifically, in the measurement process, it is not limited to a certain solution and can be widely applied to the concentration measurement of various solutions at different temperatures. The liquid concentration measurement method will be described below in combination with specific solutions.

[0079] Figure 3 It is a corresponding relationship diagram between the concentration of sodium chloride liquid and the change amount of the interference image provided by an embodiment of the present invention. See Figure 2 and Figure 3. First, configure sodium chloride standard solutions with concentrations of 0, 0.03 g / ml, 0.06 g / ml, 0.09 g / ml, 0.12 g / ml, 0.15 g / ml, 0.18 g / ml, 0.21 g / ml, 0.24 g / ml, and 0.27 g / ml. Turn on the light source emission unit to emit a laser beam. First, remove the beam expander unit, pour the sodium chloride liquid into the container. The optical path of the first detection beam will change when passing through the container. First, adjust the container to the initial position parallel to the first reflection module. Then, control the rotation angles of the rotatable first reflection module and / or the second reflection module through the processing module so that the two light spots formed by the first detection beam and the second detection beam on the detection and reception module coincide. Then, turn the beam expander unit back, adjust the position to let the laser beam pass through, and interference fringes appear on the detection and reception module. After the adjustment is completed, turn on the thermostat switch, set the temperature for preheating. In this experiment, the set temperature is 25 °C, close the chamber door, and rotate the measurement module to drive the container to rotate through the processing instruction output by the processing module to adjust the optical path when the first detection beam passes through the sodium chloride liquid in the container. As the container rotates, the optical path also changes, and it can be observed that the interference image slowly swallows and spits on the detection and reception module. Control the running time of the motor device, read the forward distance L of the micrometer device, combine the distance r from the center of the rotating shaft in the rotating device to the inner end of the micrometer head of the micrometer device, and the distance L2 from the center of the rotating shaft to the surface of the linkage rod, and substitute them into the formula to obtain the deflection angle θ of the container. During this period, collect the change amount of the interference image through the observation unit and feedback the collected change amount of the interference image to the processing module. There is a video recognition program in the processing module that counts by sensing the change in the light intensity of the interference fringes. Furthermore, the light intensity when the interference fringes swallow and spit can be directly converted into a number, that is, the video information collected in the observation unit is converted into the specific number of the change amount of the interference image, and the corresponding relationship between the change amount of the interference image of the sodium chloride liquid at this concentration is obtained.

[0080] Replace the concentration of the sodium chloride liquid in the container, repeat the above steps, obtain the change amount of the interference image of sodium chloride liquids with different concentrations at the same deflection angle, summarize the change amount of the interference image of sodium chloride liquids with different concentrations at the same deflection angle and sodium chloride liquids with different concentrations, establish the corresponding relationship between the sodium chloride liquid concentration - change amount of the interference image, and store this corresponding relationship in the processing module. Then, pour the sodium chloride solution with an unknown concentration into the container, measure the change amount of the interference image using the liquid concentration measurement system, and then, according to the corresponding relationship between the sodium chloride liquid concentration - change amount of the interference image stored in the processing module, obtain the concentration of the sodium chloride liquid.

[0081] Figure 4 is a corresponding relationship diagram between the calcium chloride liquid concentration - change amount of the interference image provided by the embodiment of the present invention. SeeFigure 2 and Figure 4 First, prepare 0, 0.0376g / ml, 0.0755g / ml, 0.1133g / ml, 0.1510g / ml, 0.2265g / ml, 0.2643g / ml, 0.3020g / ml, 0.3020g / ml, 0.3398g / ml, 0.3776g / ml calcium chloride standard solution, turn on the light source output unit, emit the laser beam, remove the beam expansion unit first, pour sodium chloride liquid into the container, the first detection beam will change when passing through the container, first adjust the container to be parallel to the first reflection module The starting position is then controlled by the processing module to control the rotation angle of the rotatable first reflection module and / or the second reflection module, so that the two light spots formed by the first detection light beam and the second detection light beam on the detection receiving module overlap, and then the beam expansion unit is turned back and the position is adjusted to allow the laser beam to pass through. Interference fringes appear on the detection receiving module. After the adjustment is completed, turn on the thermostat switch and set the temperature for preheating. The temperature is set to 25°C in this experiment. Close the door of the box, and rotate the measurement module to drive the container to rotate through the processing instructions output by the processing module to adjust the optical path of the first detection light beam when it passes through the calcium chloride liquid in the container. As the container rotates, the optical path also changes, and the interference image can be observed to be slowly throughput on the detection receiving module. Control the running time of the motor device, read out the forward distance L of the screw micrometer device, combine the distance r from the center of the rotating shaft in the rotating device to the inner side of the end of the screw micrometer head, and the distance L2 from the center of the rotating shaft to the surface of the linkage rod, and substitute them into the formula The deflection angle θ of the container is obtained, during which the variation of the interference image is collected by the observation unit, and the collected variation of the interference image is fed back to the processing module. The processing module is provided with a video recognition program that counts by sensing the variation of the light intensity of the interference fringes, and then the light intensity when the interference fringes are throughput can be directly converted into a number, that is, the video information collected in the observation unit is converted into a specific number of the variation of the interference image, and the corresponding relationship of the variation of the interference image of the calcium chloride liquid at this concentration is obtained.

[0082] The solubility of the calcium chloride liquid in the change container is repeated, the above steps are repeated, the variation of the interference image of the calcium chloride liquid of different concentrations at the same deflection angle is obtained, the variation of the interference image of the calcium chloride liquid of different concentrations at the same deflection angle obtained, and the calcium chloride liquid of different concentrations are summarized, and the corresponding relationship of the concentration of calcium chloride liquid-interference image variation is established, and the corresponding relationship is stored in the processing module. Afterwards, the solution of calcium chloride unknown concentration is loaded into a container, and the variation of the interference image is measured by a liquid concentration measurement system, then the concentration of the calcium chloride liquid can be obtained according to the corresponding relationship of the concentration of calcium chloride liquid-interference image variation stored in the processing module.

[0083] In addition, the liquid concentration measurement system can also be used to measure the concentration of solutions at different temperatures, explore the relationship between refractive index and temperature, and has a wider range of applications. Taking sodium chloride solution as an example again.

[0084] Prepare sodium chloride solutions with set concentrations, set a series of constant temperature oven temperatures to be 0°C, 5°C, 20°C, 25°C, 30°C respectively, pour in the solutions, after debugging the optical path of the liquid concentration measurement system, close the oven door, preheat to the specified temperature, rotate the measurement module to drive the container to rotate through the processing instructions output by the processing module, so as to adjust the optical path when the first detection beam passes through the sodium chloride liquid in the container. As the container rotates, the optical path also changes accordingly. It can be observed that the interference pattern slowly expands and contracts on the detection and receiving module. During this period, the change amount of the interference pattern is collected by the observation unit, and the change amount of the collected interference pattern is fed back to the processing module. There is a video recognition program in the processing module that counts by sensing the change in the light intensity of the interference fringes. Furthermore, the light intensity when the interference fringes expand and contract can be directly converted into a number, that is, the video information collected in the observation unit is converted into the specific number of the change amount of the interference pattern, obtaining the change amount of the interference pattern, establishing a functional relationship with temperature, that is, obtaining the function of concentration and the change amount of the interference pattern at different temperatures. Since the change trend of the interference pattern is consistent with that of the refractive index, the functional relationship between the refractive index and temperature can be deduced. In application, the temperature of the constant temperature oven can be flexibly adjusted according to the actual temperature, so as to better solve practical problems.

[0085] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described here. Various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, it can also include more other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A liquid concentration measurement system, characterized in that, It includes a light source module, a beam splitting module, a container, a first reflection module, a second reflection module, a detection and receiving module, a rotation measurement module, and a processing module; The light source module is used to emit a detection beam; The beam splitting module is located on the propagation path of the detection beam and is used to split the detection beam into a first detection beam and a second detection beam; The container is used to hold the liquid to be detected, and the container is located on the propagation path of the first detection beam; the first detection beam is incident on the detection and receiving module after passing through the liquid to be detected, being reflected by the first reflection module and transmitted by the beam splitting module in sequence; the second detection beam is incident on the detection and receiving module after being reflected by the second reflection module and reflected by the beam splitting module in sequence; The rotation measurement module is electrically connected to the processing module and is connected to the container, and is used to drive the container to rotate according to the processing instruction output by the processing module to adjust the optical path of the first detection beam passing through the liquid to be detected; The processing module is electrically connected to the detection and receiving module and is used to determine the concentration of the liquid to be detected according to the interference image in the detection and receiving module; The liquid concentration measurement system further includes a compensation module; the compensation module is located in the optical path between the beam splitting module and the second reflection module and is used to adjust the optical path of the second detection beam; The beam splitting module is arranged in parallel with the compensation module and intersects with the light output direction of the light source module; The inclination direction of the beam splitting module and the compensation module forms a 45° angle with the light output direction of the light source module; The rotation measurement module includes a micrometer device, a motor device, a linkage rod, and a rotation device; The micrometer device includes a knob and a micrometer head, the motor device includes a rotating shaft, the knob is engaged with the rotating shaft, the micrometer head is fixed to one side of the linkage rod, and the other side of the linkage rod is fixed to the surface of the container; the rotation device is fixed in the optical path between the first reflection module and the beam splitting module, and the rotation device includes a rotating shaft, and the container is fixed on the rotating shaft.

2. The liquid concentration measurement system according to claim 1, characterized in that, The first reflection module and / or the second reflection module is rotatable; The processing module is electrically connected to the rotatable first reflection module and / or the second reflection module and is used to control the rotation angle of the first reflection module and / or the second reflection module so that the first detection beam coincides with the second detection beam to form an interference image.

3. The liquid concentration measurement system according to claim 1, wherein The light source module includes a light source output unit and a beam expanding unit; The light source output unit is used to emit a laser beam; The beam expanding unit is located on the propagation path of the laser beam and is used to expand the laser beam to form the detection beam.

4. The liquid concentration measurement system according to claim 1, characterized in that, The detection and receiving module includes a receiving and imaging unit and an observation unit; The receiving and imaging unit is located in the optical path between the beam splitting module and the observation unit and is used to receive the first detection beam and the second detection beam and form an image; The observation unit is used to collect the interference image of the first detection beam and the second detection beam and feedback it to the processing module.

5. The liquid concentration measurement system according to claim 1, wherein The beam splitting module includes a beam splitting plate; The beam splitter includes a beam splitter body and a semi-transmissive and semi-reflective film disposed on the surface of the beam splitter body.

6. The liquid concentration measurement system according to claim 1, wherein The liquid concentration measurement system further includes a thermostat; the light source module, the beam splitting module, the container, the first reflection module, the second reflection module, the detection and reception module, and the rotation measurement module are all located in the thermostat.

7. A method for measuring the concentration of a liquid, applied to the liquid concentration measurement system according to any one of claims 1-6, characterized in that, The liquid concentration measurement method includes: Adjust the rotation measurement module to determine the deflection angle of the container; Obtain an interference image; Repeat the above steps to obtain the change amount of the interference images of the liquids to be detected with different concentrations at the same deflection angle; According to the change amount of the interference images corresponding to the liquids to be detected with different concentrations at the same deflection angle, obtain the corresponding relationship between the solution concentration and the change amount of the interference images; Determine the concentration of the liquid to be detected according to the corresponding relationship.

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