Real-time liquid concentration optical intelligent measuring device

Abstract

The present disclosure belongs to the technical field of optical imaging, and discloses a real-time liquid concentration optical intelligent measuring device, which comprises a tunable semiconductor laser, a laser regulator, a plane array charge coupled device (CCD), an image processing module, a plano-convex optical cavity, an optical collimation and beam expansion system, a display screen and a data analysis module, the tunable semiconductor laser emits laser under the control of the laser regulator, the laser passes through the optical collimation and beam expansion system and then passes through the plano-convex optical cavity, and finally is received by the plane array charge coupled device (CCD). Dynamic wavelength control based on the tunable semiconductor laser is adopted to realize the automatic switching of multiple output wavelengths at a fixed time, increase the amount of data for machine learning, and greatly improve the concentration measurement precision; and the embedded image acquisition and processing system based on the ARM neural network algorithm is used to perform digital signal processing and neural network training on the optical path signals received by the high-resolution plane array charge coupled device (CCD), so that the measuring system has the significant advantages of high stability and fast response.

Description

TECHNICAL FIELD

[0001] The present disclosure belongs to the technical field of optical imaging, and particularly relates to a real-time liquid concentration optical intelligent measuring device. BACKGROUND

[0002] Concentration is an important characteristic of medium liquid, and precise measurement of solution concentration is often required in the fields of chemical industry, metallurgy, papermaking, sugar making, environmental protection industry and scientific research, which is an important technical means to ensure and improve quality. Compared with chemical detection method and microwave detection method, optical detection method has higher sensitivity and faster response. The methods widely used in optical detection method include polarimeter method and spectrophotometry. The polarimeter method measures the concentration of the solution by using the quantitative relationship between the number of chiral molecules in the solution and the optical rotation. The spectrophotometry measures the absorbance or luminous intensity of the object to be measured at a specific wavelength or a certain wavelength range, and then analyzes and compares the relationship curve between the absorbance and the concentration to obtain the solution concentration by using the Beer-Lambert law.

[0003] The polarimeter method has obvious physical phenomena and intuitive principle, but its operation is complex, the measurement period is long, and long-term use will cause the sensitivity of the human eye to the field of view to decrease, resulting in a large error, which is not suitable for continuous dynamic measurement of liquid concentration. Although the spectrophotometry has high precision and convenient operation, the spectrophotometer has very strict requirements for the operation environment and method, the application scene is limited, and the price is expensive.

[0004] Therefore, a real-time liquid concentration optical intelligent measuring device is proposed. SUMMARY

[0005] In view of the deficiencies of the prior art, the purpose of the present disclosure is to provide a real-time liquid concentration optical intelligent measuring device. The optical imaging system in the device can capture the slight change of the liquid concentration in real time, and the embedded electronic circuit and the machine learning algorithm are combined to process and train the collected data, so as to realize intelligent measurement with high precision and fast response, and greatly liberate human resources. Since the present application is highly integrated, it has no strict environmental requirements and wide application scenarios.

[0006] The purpose of the present disclosure can be achieved by the following technical solutions:

[0007] The application discloses a real-time liquid concentration optical intelligent measuring device, which comprises a tunable semiconductor laser, a laser regulator, a liquid pump, a plane array charge coupled device (CCD), an image processing module, a plano-convex optical cavity, an optical collimation and beam expansion system, a display screen, a data analysis module and a battery, the tunable semiconductor laser controls emitted laser to pass through the optical collimation and beam expansion system and then pass through the plano-convex optical cavity to be received by the plane array charge coupled device (CCD), the output end of the plane array charge coupled device (CCD) is connected with the input end of the image processing module, the output end of the image processing module is connected with the input end of the data analysis module, the output end of the data analysis module is connected with the input end of the display screen, and the battery is electrically connected with the tunable semiconductor laser and the laser regulator.

[0008] Preferably, the tunable semiconductor laser switches the wavelength of the output light in the range of 400-700 nm through the laser regulator.

[0009] Preferably, two through holes are formed in the upper part of the plano-convex optical cavity, and the two through holes are connected with the liquid pump through two thin tubes.

[0010] Preferably, the solution concentration in the plano-convex optical cavity corresponds to the light spot image collected by the plane array charge coupled device (CCD).

[0011] According to another aspect of the application, the application provides an optical imaging system comprising the real-time liquid concentration optical intelligent measuring device, which comprises a tunable semiconductor laser, an optical collimation and beam expansion system, a plano-convex optical cavity, a liquid pump and a plane array charge coupled device (CCD), the liquid pump is connected with the plano-convex optical cavity, the tunable semiconductor laser emits a light beam to the optical collimation and beam expansion system to form a collimated parallel light beam, the optical collimation and beam expansion system comprises a beam expander and a collimator, the beam expander and the collimator are both convex lenses, the focal length of the beam expander is 10 mm, the focal length of the collimator is 50 mm, the distance between the beam expander and the tunable semiconductor laser is 20 mm, the distance between the collimator and the beam expander is 60 mm, and the plane array charge coupled device (CCD) is arranged at a position 50 mm away from the plano-convex optical cavity.

[0012] According to another aspect of the application, the application provides an image acquisition and processing system comprising the real-time liquid concentration optical intelligent measuring device, which comprises a plane array charge coupled device (CCD), a video A / D converter, a memory, an ARM and a CPLD, the plane array charge coupled device (CCD) collects different wavelength light signals into the video A / D, the video A / D converter is initialized by the ARM to output image data into the memory under the control of the CPLD, and the ARM reads the image data to train a neural network and construct a machine learning model.

[0013] Advantages of the present disclosure:

[0014] The present application adopts dynamic wavelength control based on a tunable semiconductor laser to realize timed automatic switching of multiple output wavelengths, increases the amount of data for machine learning, and greatly improves the concentration measurement accuracy. Further, the embedded image acquisition and processing system based on the ARM neural network algorithm performs digital signal processing and neural network training on the optical signal received by the high-resolution area array charge coupled device (CCD), so that the measurement system has the significant advantages of high stability and fast response. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced. Obviously, for those skilled in the art, other drawings can also be obtained without creative labor on the basis of these drawings.

[0016] Figure 1 is a schematic diagram of a real-time liquid concentration optical intelligent measurement device of the present disclosure embodiment;

[0017] Figure 2 is a schematic diagram of an optical imaging system structure of the present disclosure embodiment;

[0018] Figure 3 is a planar-convex optical cavity imaging principle diagram of the present disclosure embodiment;

[0019] Figure 4 is a block diagram of an image acquisition and processing system of the present disclosure embodiment.

[0020] In the figure: (1) tunable semiconductor laser; (2) laser regulator; (3) liquid pump; (4) area array charge coupled device (CCD); (5) image processing module; (6) planar-convex optical cavity; (7) optical collimation and beam expansion system; (8) display screen; (9) data analysis module; (10) battery. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present disclosure will be described clearly and completely below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present disclosure.

[0022] The application discloses a real-time liquid concentration optical intelligent measuring device, which comprises a tunable semiconductor laser 1, a laser regulator 2, a plane array charge coupled device (CCD) 3, a liquid pump 4, an image processing module 5, a plano-convex optical cavity 6, an optical collimation and beam expansion system 7, a display screen 8 and a data analysis module 9, the tunable semiconductor laser 1 is controlled by the laser regulator 2 to emit laser, the laser is received by the plane array charge coupled device (CCD) 4 after passing through the optical collimation and beam expansion system 7 and the plano-convex optical cavity 6, the output end of the plane array charge coupled device (CCD) 4 is connected with the input end of the image processing module 5, the output end of the image processing module 5 is connected with the input end of the data analysis module 9, and the output end of the data analysis module 9 is connected with the input end of the display screen 8. The device further comprises a battery 10, and the battery 10 is electrically connected with the tunable semiconductor laser 1 and the laser regulator 2.

[0023] The solution is continuously pumped into and out of the plano-convex optical cavity 6 by the liquid pump 3, the liquid completely fills the plano-convex optical cavity 6 by controlling the flow rate, the real-time updating of the solution to be measured is realized, the tunable semiconductor laser 1 is controlled by the laser regulator 2 to realize the timing switching control of the dynamic output wavelength, a plurality of wavelengths of laser are continuously emitted in a short time period, the battery 10 can ensure the normal work of the laser regulator 2 and the tunable semiconductor laser 1, the laser passes through the optical collimation and beam expansion system 7, passes through the plano-convex optical cavity 6 containing the solution to be measured and is received by the plane array charge coupled device (CCD) 4, the image processing module 5 carries out digital signal processing and storage on the optical signal collected by the plane array charge coupled device (CCD) 4, the neural network training is carried out on the massive data established in the image processing module by the data analysis module 9, and the machine learning model of the liquid concentration and the corresponding optical signal is obtained. The image data corresponding to the solution to be measured is input into the model, and finally the concentration of the solution to be measured is displayed on the display screen 8.

[0024] The optical imaging system is composed of the tunable semiconductor laser 1, the optical collimation and beam expansion system 7, the plano-convex optical cavity 6, the liquid pump 3 and the plane array charge coupled device (CCD) 4, Figure 2 It is a structural schematic diagram of the optical imaging system. The tunable semiconductor laser can realize the timing automatic switching of a plurality of output wavelengths under the control of the laser regulator; the plano-convex cavity is made of high-transmittance silica optical glass, two holes are formed in the upper part of the cavity, and the two holes are connected with the liquid pump through two thin pipes.

[0025] From the interaction relationship between light and matter, the relationship between the concentration of the solution and the refractive index thereof can be obtained: when the light frequency acting on the solution is constant, the concentration of the solution is approximately linearly related to the refractive index thereof.

[0026] When measuring, the liquid pump injects the liquid to be measured into the plano-convex cavity, and the liquid fills the cavity by automatically controlling the flow rate.

[0027]

[0028] In the formula, n and n' are the refractive indexes of the liquid to be measured and air respectively, l and l' are the distances from the object point and the image point to the convex spherical surface respectively, and -r is the radius of curvature of the convex spherical surface.

[0029] Figure 3 The plano-convex optical cavity imaging principle diagram is shown in FIG. 1. According to formula (1), when the parallel light beam passes through the left plane, no refraction occurs, and the parallel light still propagates in the liquid to be measured.

[0030] When the parallel light beam passes through the convex spherical surface on the right side of the cavity, according to the geometric relationship, the relationship between the radius h of the parallel light beam and the radius H of the light beam at the position L away from the convex spherical surface is as follows:

[0031]

[0032] By combining formula (1) and formula (2), the following formula is obtained:

[0033]

[0034] In the formula, n and n' are the refractive indexes of the liquid to be measured and air respectively, l and l' are the distances from the object point and the image point to the convex spherical surface respectively, and -r is the radius of curvature of the convex spherical surface. Both of them are constants, so the radius H of the light beam and the refractive index of the liquid satisfy a negative linear relationship.

[0035] Therefore, the concentration of the solution in the plano-convex optical cavity has a one-to-one corresponding relationship with the radius H and the intensity of the light beam on the receiving screen.

[0036] In order to accurately measure the changes in the width and intensity of the light beam, a face array charge coupled device (CCD) is placed at the position L away from the cavity to collect the optical signals of the optical cavity passing through the real-time liquid.

[0037] In the present patent, in order to improve the measurement accuracy, the chromatic aberration of the optical material is used to increase the amount of machine learning data. The chromatic aberration is caused by the different refractive indexes of the optical material for different wavelengths of colored light, so for light beams of different wavelengths, formula (3) should be changed to

[0038]

[0039] ​We carry out the timing switch control of the dynamic output wavelength of the tunable semiconductor laser, continuously emit N kinds of wavelength laser in a short time period, make the surface array charge coupled device (CCD) collect the image data corresponding to different output wavelengths under the same concentration, realize N times data expansion.

[0040] The block diagram of the ARM neural network embedded image acquisition and processing system is shown in Figure 4 The system selects high-resolution surface array CCD, video A / D converter, memory, ARM and CPLD to form the image acquisition and processing system. The surface array charge coupled device (CCD) is used as the optical image capture element to collect different wavelength optical signals and transmit them into the video A / D. The video A / D converter is initialized by the ARM, and the output image data is stored in the memory under the control of the CPLD. Finally, the ARM reads the image data, carries out neural network training, constructs the machine learning model, and finally obtains the concentration of the solution to be measured.

[0041] In the description of the present specification, the description referring to the terms "one embodiment", "an example", "a specific example" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0042] The basic principles, main features and advantages of the present disclosure are shown and described above. It should be understood by those skilled in the art that the present disclosure is not limited by the above embodiments, and the above embodiments and descriptions in the specification are only to illustrate the principles of the present disclosure. Without departing from the spirit and scope of the present disclosure, various changes and improvements can be made to the present disclosure, and these changes and improvements all fall within the scope of the claimed present disclosure.

Claims

1. A real-time liquid concentration optical intelligent measuring device, comprising a tunable semiconductor laser (1), a laser regulator (2), a liquid pump (3), a plane array charge coupled device (CCD) (4), an image processing module (5), a plano-convex optical cavity (6), an optical collimation beam expanding system (7), a display screen (8), a data analysis module (9) and a battery (10), characterized in that, The tunable semiconductor laser (1) is controlled by the laser regulator (2), and the emitted laser is received by the area array charge coupled device (CCD) (4) through the optical collimation beam expansion system (7) and the plano-convex optical cavity (6), the output end of the area array charge coupled device (CCD) (4) is connected with the input end of the image processing module (5), the output end of the image processing module (5) is connected with the input end of the data analysis module (9), the output end of the data analysis module (9) is connected with the input end of the display screen (8), and the battery (10) is electrically connected with the tunable semiconductor laser (1) and the laser regulator (2); The tunable semiconductor laser (1) switches the wavelength of the output laser in the range of 400nm-700nm through the laser regulator (2), realizes the timing switching of multiple output wavelengths, makes the area array charge coupled device (CCD) (4) collect the image data corresponding to different output wavelengths under the same concentration, and expands the training data set for the data analysis module (9) to construct a neural network model, so that the solution concentration measurement precision is improved. The solution concentration in the plano-convex optical cavity (6) corresponds to the light spot image collected by the area array charge coupled device (CCD) (4) in a one-to-one manner.

2. A real-time liquid concentration optical intelligent measuring device according to claim 1, characterized in that, Two through holes are formed in the upper part of the plano-convex optical cavity (4), and the two through holes are connected with the liquid pump (3) through two thin tubes. 3.An optical imaging system comprising the real-time liquid concentration optical intelligent measurement device of any one of claims 1-2, comprising a tunable semiconductor laser (1), an optical collimation beam expansion system (7), a plano-convex optical cavity (6), a liquid pump (3) and an area array charge coupled device (CCD) (4), the liquid pump (3) is connected with the plano-convex optical cavity (6), the tunable semiconductor laser (1) emits a light beam to the optical collimation beam expansion system (7) to form a collimated parallel light beam, the optical collimation beam expansion system (7) comprises a beam expander and a collimator, both the beam expander and the collimator are convex lenses, the focal length of the beam expander is 10mm, the focal length of the collimator is 50mm, the distance between the beam expander and the tunable semiconductor laser (1) is 20mm, and the distance between the collimator and the beam expander is 60mm, and the area array charge coupled device (CCD) (4) is placed at a position 50mm away from the plano-convex optical cavity (6). 4.An image acquisition and processing system comprising the real-time liquid concentration optical intelligent measurement device of any one of claims 1-2, comprising an area array charge coupled device (CCD), an A / D converter, a memory, a 32-bit reduced instruction set processor architecture ARM processor and a complex programmable logic device (CPLD), the area array charge coupled device (CCD) collects different wavelength light signals into the A / D converter, the A / D converter is initialized by the ARM processor, the output image data is transmitted into the memory under the control of the CPLD, and the ARM reads the image data to train the neural network and construct a machine learning model.

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