阅读说明：本技术 一种液体中可溶性固体物含量的多光谱检测方法、系统及存储介质 (Multispectral detection method and system for content of soluble solids in liquid and storage medium ) 是由 谢捷斌 于 2021-08-31 设计创作，主要内容包括：本发明公开了一种液体中可溶性固体物含量的多光谱检测方法,包括控制位于三棱镜一侧的多色光源发出光束以一定角度入射到三棱镜与待测液体临界面,在所述临界面上发生全反射,反射光线行经聚焦透镜后投射到位于三棱镜另一侧的感光器件上；获取所述感光器件上所有像素的光强度信息,找到每个波长对应的光强度的峰值位置P；根据柯西色散公式、全反射角度θ与峰值P-(M)的关系计算不同波长对应的液体折射率；计算不同波长对应的液体浓度；取不同波长对应的液体浓度的平均值作为测定的液体浓度。相比现有技术,本方案具有更好的抗干扰性,更高的精度和准确度。(The invention discloses a multispectral detection method for the content of soluble solids in liquid, which comprises the steps of controlling a multicolor light source positioned on one side of a triple prism to emit light beams which enter the triple prism and a critical surface of liquid to be detected at a certain angle, carrying out total reflection on the critical surface, and projecting reflected light rays onto a photosensitive device positioned on the other side of the triple prism after passing through a focusing lens; acquiring light intensity information of all pixels on the photosensitive device, and finding a peak position P of light intensity corresponding to each wavelength; according to the Cauchy's dispersion formula, the total reflection angle theta and the peak value P M Calculating the refractive indexes of the liquid corresponding to different wavelengths; calculating the liquid concentrations corresponding to different wavelengths; the average value of the liquid concentrations corresponding to different wavelengths is taken as the measured liquid concentration. Compared with the prior art, the scheme has better anti-interference performance and higher precision and accuracy.)

1. A multispectral detection method for the content of soluble solids in a liquid is characterized by comprising

Controlling a multi-color light source positioned on one side of a triple prism to emit light beams to enter a triple prism and a critical surface of liquid to be measured at a certain angle, totally reflecting on the critical surface, and projecting reflected light rays to a photosensitive device positioned on the other side of the triple prism after passing through a focusing lens;

acquiring and recording light intensity information of all pixels on the photosensitive device;

finding the peak position P of the light intensity corresponding to each wavelength in the light intensity information, and marking the peak position P as P₁,P₂,…,P_MWhere M is the number of wavelengths in the spectrum;

according to the Cauchy's dispersion formula, the total reflection angle theta and the peak value P_MCalculating the refractive indexes of the liquid corresponding to different wavelengths;

calculating the liquid concentration corresponding to different wavelengths according to the formula c ═ k × n + b, wherein c is the concentration of the liquid, and k and b are constants for the specific wavelength;

the average value of the liquid concentrations corresponding to different wavelengths is taken as the measured liquid concentration.

2. The method of claim 1 wherein said light sensing device is a linear CCD/CMOS array comprising a plurality of pixels and said plurality of pixels are linearly arranged in one dimension along a line of light dispersion.

3. The method of claim 1 wherein said step of controlling the emission of a light beam from a polychromatic light source comprises: the control unit generates a trigger signal according to an input or automatically generated instruction, the trigger signal is sent to a driving circuit carried by the multicolor light source, and the driving circuit controls the multicolor light source to emit light formed by mixing one or more of red light, yellow light and blue light according to the trigger signal.

4. The method of claim 3 wherein said drive circuit is modulated by a pulse signal to control the emission parameters of said polychromatic light source, said emission parameters including at least one or more of emission intensity and emission time.

5. The method of claim 1 wherein said step of obtaining and recording light intensity information for all pixels on said light sensitive device comprises: the control unit generates a trigger signal according to an input or automatically generated instruction, the trigger signal is sent to the data reading circuit, the data reading circuit reads the light intensity information of all pixels on the photosensitive device according to the trigger signal, and the light intensity information is stored in the storage unit.

6. The method of claim 5 wherein said step of said data reading circuit reading light intensity information for all pixels on said light sensing device based on said trigger signal comprises: and amplifying the electric signal in an electronic gain mode, and carrying out digital sampling on the amplified electric signal to obtain a signal numerical value of light intensity.

7. The method of claim 1 wherein the light intensity information is used to find the peak position P of the light intensity at each wavelength, denoted as P₁,P₂,…,P_MComprises the following steps: the acquired light intensity signal values of all the pixels are expressed as G ═ G by a one-dimensional array G₁,g₂,...,g_k]And k is the number of pixels, the change interval of the array G is divided according to the wavelength type of the light emitted by the multicolor light source, and the position of the maximum value in each interval is determined as the peak position P.

8. The method of claim 1 wherein the method is based on the Cauchy's dispersion formula, total reflection angle θ and peak value P_MThe method for calculating the refractive indexes of the liquid corresponding to different wavelengths comprises the following steps:

according to Snell's law of reflection, there is the following relationship between the angle of reflection and the refractive index:

n₂＝n₁*sin(θ) (1)

where θ is the angle of reflection, n₁Is the refractive index of the prism, n₂Is the refraction of the liquid to be measuredRate, sin () represents a sine function;

the cauchy dispersion formula states that the refractive index varies with wavelength:

n(λ)＝A+B/λ²+C/λ⁴ (2)

wherein n is the refractive index, λ is the wavelength of light, and A, B, and C are constants;

the angle θ of total reflection is calculated from the peak position P according to equation (3):

sin(θ)＝f(P) (3)

wherein the function f () is fitted with an approximately linear relationship: f (x) a x + c, the values of a and c depending on the geometrical relationship of the triangular prism, the focusing lens and the photosensitive device;

combining formula (1) to formula (3) yields:

n_j＝(A+B/λ²+C/λ⁴)*f(P_j) (4)。

9. a multispectral detection system for the content of soluble solids in liquid is characterized by comprising a multicolor light source, a prism and a photosensitive device;

the device comprises a light source, a light sensing device, a data reading circuit, a control unit and a multi-color light source, wherein the multi-color light source is arranged on one side of the triple prism, emission light of the multi-color light source is projected to a critical surface of the triple prism and liquid to be measured, the light sensing device is arranged on the other side of the triple prism, reflected light of the emission light reflected by the critical surface is projected to the light sensing device, the light sensing device is connected with the data reading circuit and used for obtaining light intensity information of all pixels on the light sensing device, and the reading circuit and the multi-color light source are connected to the control unit;

the control unit comprises an instruction input/generation module, a trigger signal generation module, a storage module, a calculation module, a display module and a control module;

the instruction input/generation module is used for receiving or generating a control instruction; the trigger signal generating module is used for generating a trigger signal according to the control instruction and sending the trigger signal to a driving circuit or a data reading circuit of the multicolor light source; the storage module is used for storing data; the computing module is used for being arranged atFinding the peak position P of light intensity corresponding to each wavelength in the light intensity information, and marking as P₁,P₂,…,P_MWherein M is the number of wavelengths in the spectrum, according to the Cauchy dispersion formula, the total reflection angle theta and the peak value P_MCalculating the refractive index of the liquid corresponding to different wavelengths according to the formula c ═ k × n + b, wherein c is the concentration of the liquid, k and b are constants for specific wavelengths, and taking the average value of the liquid concentrations corresponding to different wavelengths as the measured liquid concentration; the display module is used for displaying the refractive index and/or concentration value; the control module is used for controlling the modules.

10. A computer readable storage medium having stored therein at least one instruction, at least one program, set of codes or set of instructions, which is loaded and executed by a processor to carry out the operations performed in the method of multi-spectral detection of soluble solids content in a liquid according to any one of claims 1 to 8.

Technical Field

The invention relates to the technical field of concentration measurement, in particular to a multispectral detection method and system for content of soluble solids in liquid and a storage medium.

Background

The refractive index of the liquid is related to the total amount of soluble solids in the liquid, and by measuring the refractive index of the liquid, the total amount of dissolved sugar or other solids in the liquid can be inferred. A common method for measuring the refractive index of a liquid is to use a refractometer, which calculates the refractive index by measuring the angle of refraction of a prism to an incident light according to Snell's Law.

Currently, most refractometers use a band pass Filter (Bandpass Filter) to Filter light with a single wavelength for refractive index measurement, because at a fixed wavelength, the refractive index has a unique corresponding relationship with the refractive angle. However, such a measurement method has certain problems, for example, some liquids may absorb light with specific wavelength, and if the light for measurement is absorbed by the liquid to be measured, the measurement result will be inaccurate. In addition, this type of measurement is also susceptible to ambient light, which can interfere with the measurement results. Therefore, how to improve the accuracy of the concentration measurement of the prior refractometer and the anti-interference performance of the instrument is a topic with great research significance.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides a multispectral detection method for the content of soluble solids in liquid.

In order to achieve the purpose, the invention provides the following technical scheme:

a multispectral detection method for soluble solid content in liquid comprises

Controlling a multi-color light source positioned on one side of a triple prism to emit light beams to enter a triple prism and a critical surface of liquid to be measured at a certain angle, totally reflecting on the critical surface, and projecting reflected light rays to a photosensitive device positioned on the other side of the triple prism after passing through a focusing lens;

acquiring and recording light intensity information of all pixels on the photosensitive device;

finding the peak position P of the light intensity corresponding to each wavelength in the light intensity information, and marking the peak position P as P₁,P₂,…,P_MWhere M is the number of wavelengths in the spectrum;

according to the Cauchy's dispersion formula, the total reflection angle theta and the peak value P_MCalculating the refractive indexes of the liquid corresponding to different wavelengths;

calculating the liquid concentration corresponding to different wavelengths according to the formula c ═ k × n + b, wherein c is the concentration of the liquid, and k and b are constants for the specific wavelength;

the average value of the liquid concentrations corresponding to different wavelengths is taken as the measured liquid concentration.

Further, the photosensitive device is a linear CCD/CMOS array which includes a plurality of pixels and the plurality of pixels are one-dimensionally and linearly arranged along a linear direction of light dispersion.

Further, the step of emitting a light beam by the multicolor light source comprises: the control unit generates a trigger signal according to an input or automatically generated instruction, the trigger signal is sent to a driving circuit carried by the multicolor light source, and the driving circuit controls the multicolor light source to emit light formed by mixing one or more of red light, yellow light and blue light according to the trigger signal.

Further, the driving circuit controls the light-emitting parameters of the multicolor light source through pulse signal modulation, and the light-emitting parameters at least comprise one or more of light-emitting intensity and light-emitting time.

Further, the step of acquiring and recording light intensity information of all pixels on the photosensitive device comprises: the control unit generates a trigger signal according to an input or automatically generated instruction, the trigger signal is sent to the data reading circuit, the data reading circuit reads the light intensity information of all pixels on the photosensitive device according to the trigger signal, and the light intensity information is stored in the storage unit.

Further, the step of reading the light intensity information of all the pixels on the photosensitive device by the data reading circuit according to the trigger signal comprises: and amplifying the electric signal in an electronic gain mode, and carrying out digital sampling on the amplified electric signal to obtain a signal numerical value of light intensity.

Further, finding the peak position P of the light intensity corresponding to each wavelength in the light intensity information, and marking the peak position P as P₁,P₂,…,P_MComprises the following steps: the acquired light intensity signal values of all the pixels are expressed as G ═ G by a one-dimensional array G₁,g₂,...,g_k]And k is the number of pixels, the change interval of the array G is divided according to the wavelength type of the light emitted by the multicolor light source, and the position of the maximum value in each interval is determined as the peak position P.

Further, according to the Cauchy dispersion formula, the total reflection angle theta and the peak value P_MThe method for calculating the refractive indexes of the liquid corresponding to different wavelengths comprises the following steps:

according to Snell's law of reflection, there is the following relationship between the angle of reflection and the refractive index:

n₂＝n₁*sin(θ) (1)

where θ is the angle of reflection, n₁Is the refractive index of the prism, n₂Is the refractive index of the liquid to be measured, sin () represents a sine function;

the cauchy dispersion formula states that the refractive index varies with wavelength:

n(λ)＝A+B/λ²+C/λ⁴ (2)

wherein n is the refractive index, λ is the wavelength of light, and A, B, and C are constants;

the angle θ of total reflection is calculated from the peak position P according to equation (3):

sin(θ)＝f(P) (3)

wherein the function f () is fitted with an approximately linear relationship: f (x) a x + c, the values of a and c depending on the geometrical relationship of the triangular prism, the focusing lens and the photosensitive device;

combining formula (1) to formula (3) yields:

n_j＝(A+B/λ²+C/λ⁴)*f(P_j) (4)。

according to another aspect of the present invention, there is provided a multispectral detection system for soluble solids content in a liquid, comprising a polychromatic light source, a prism, and a photosensitive device;

the device comprises a light source, a light sensing device, a data reading circuit, a control unit and a multi-color light source, wherein the multi-color light source is arranged on one side of the triple prism, emission light of the multi-color light source is projected to a critical surface of the triple prism and liquid to be measured, the light sensing device is arranged on the other side of the triple prism, reflected light of the emission light reflected by the critical surface is projected to the light sensing device, the light sensing device is connected with the data reading circuit and used for obtaining light intensity information of all pixels on the light sensing device, and the reading circuit and the multi-color light source are connected to the control unit;

the control unit comprises an instruction input/generation module, a trigger signal generation module, a storage module, a calculation module, a display module and a control module;

the instruction input/generation module is used for receiving or generating a control instruction; the trigger signal generating module is used for generating a trigger signal according to the control instruction and sending the trigger signal to a driving circuit or a data reading circuit of the multicolor light source; the storage module is used for storing data; the calculation module is used for finding the peak position P of the light intensity corresponding to each wavelength in the light intensity information, and the peak position P is marked as P₁,P₂,…,P_MWherein M is the number of wavelengths in the spectrum, according to the Cauchy dispersion formula, the total reflection angle theta and the peak value P_MCalculating the refractive index of the liquid corresponding to different wavelengths according to the formula c ═ k × n + b, wherein c is the concentration of the liquid, k and b are constants for specific wavelengths, and taking the average value of the liquid concentrations corresponding to different wavelengths as the measured liquid concentration; the display module is used for displaying the refractive index and/or concentration value; the control module is used for controlling the modules.

According to a further aspect of the present invention there is provided a computer readable storage medium having stored therein at least one instruction, at least one program, set of codes or set of instructions, which is loaded and executed by a processor to carry out the operations carried out in the method of multi-spectral detection of soluble solids content in a liquid as described above.

The invention has the beneficial effects that:

the invention provides a design scheme adopting multiple spectrums (three-color LED lamps), and focuses light rays with different wavelengths at different positions of a photosensitive device by utilizing the principle that a prism has different light refraction angles to light rays with different wavelengths, thereby realizing the multiple spectrums to measure the content of soluble solids in liquid. Compared with the traditional single-wavelength scheme, the scheme has better anti-interference performance and higher precision and accuracy.

Drawings

FIG. 1 is a schematic diagram of a system for multi-spectral detection of soluble solids content in a liquid according to an embodiment of the present invention.

FIG. 2 is a waveform of pixel signal intensity read out from a photosensitive device of a system for multispectral detection of soluble solids content in a liquid according to one embodiment of the present invention.

FIG. 3 is a flow chart of a method for multi-spectral detection of soluble solids content in a liquid according to one embodiment of the present invention.

FIG. 4 is a schematic diagram of a control unit of a multispectral detection system for soluble solids content in a liquid according to an embodiment of the present invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

The present invention will be described in detail with reference to the following examples.

Referring to fig. 1, a method for multispectral detection of soluble solids content in a liquid includes the following steps:

controlling a multi-color light source positioned on one side of a triple prism to emit light beams to enter a triple prism and a critical surface of liquid to be measured at a certain angle, totally reflecting on the critical surface, and projecting reflected light rays to a photosensitive device positioned on the other side of the triple prism after passing through a focusing lens;

acquiring and recording light intensity information of all pixels on the photosensitive device;

finding the peak position P of the light intensity corresponding to each wavelength in the light intensity information, and marking the peak position P as P₁,P₂,…,P_MWhere M is the number of wavelengths in the spectrum;

according to the Cauchy's dispersion formula, the total reflection angle theta and the peak value P_MCalculating the refractive indexes of the liquid corresponding to different wavelengths;

calculating the liquid concentration corresponding to different wavelengths according to the formula c ═ k × n + b, wherein c is the concentration of the liquid, and k and b are constants for the specific wavelength;

the average value of the liquid concentrations corresponding to different wavelengths is taken as the measured liquid concentration.

According to an embodiment of the present invention, in particular, the triangular prism 2 is placed between the multicolor light source 1 and the photosensitive device 3, and the triangular prism 2 has an inverted trapezoid shape, and the upper surface of the triangular prism contacts the liquid 4 to be measured. The internal angle range of the bottom of the trapezoidal prism 2 is 120-160 degrees. Preferably, the internal angle of the bottom of the trapezoidal prism 2 may be 135 °. Further, the material of the triangular prism 2 may be borosilicate glass (K9) or polymethyl methacrylate (PMMA). The multicolor light source 1 is arranged on one side of the triangular prism 2, light emitted by the multicolor light source 1 is projected to the triangular prism 2 and a critical surface of liquid to be measured, and an included angle between incident light and the critical surface can be adjusted by adjusting the position of the multicolor light source 1. The other side of the triangular prism 2 is provided with the photosensitive device 3, and the emitted light is projected onto the photosensitive device 3 through the reflected light reflected by the critical surface. A focusing lens 7 can be further arranged on the light path of the reflected light between the triangular prism 2 and the photosensitive device 3, and the reflected light is converged on the photosensitive device 3 after passing through the focusing lens 7. According to an embodiment of the invention, the focusing lens may be a convex lens, and the focal length thereof may be in the range of 3mm to 30 mm. The light sensing device 3 is a sensor for converting an optical signal into an electronic signal, and may be specifically a linear Charge Coupled Device (CCD), or a linear Complementary Metal Oxide Semiconductor (CMOS), which includes a plurality of pixels arranged linearly in one dimension along a linear direction of light dispersion. The number of the pixels may be 32-1000 specifically, and preferably may be 100-1000. Each pixel may contain components such as a photodiode, a memory cell, an amplification circuit, and the like.

The step of controlling the light beam emitted by the multicolor light source comprises the following steps: the control unit 6 generates a trigger signal according to an input or automatically generated instruction, and sends the trigger signal to a driving circuit 11 carried by the multicolor light source, and the driving circuit 11 controls the multicolor light source 1 to emit light mixed by one or more of red, yellow and blue light according to the trigger signal.

According to an embodiment of the present invention, the multicolor light source 1 may be a three-color LED lamp, which may emit light mixed with one or more of red, yellow and blue light. Wherein the wavelength of red light is 650nm, the wavelength of yellow light is 580nm, the wavelength of blue light is 440nm, and the light with various colors can be obtained by adjusting the three colors or the proportion of any two colors. Drive circuit 11 of tristimulus LED lamp is steerable its light that sends different wavelengths, drive circuit 11 can by control unit 6 control, according to the trigger signal that control unit 6 provided, drive circuit 11 can control every colour of tristimulus LED lamp is luminous in proper order, or makes the LED of two colours luminous simultaneously, or makes the LED of three colour luminous simultaneously. The driving circuit 11 can also control parameters such as the light emitting intensity, the light emitting time and the like of the three-color LED lamp through pulse signal modulation.

The step of acquiring and recording light intensity information of all pixels on the photosensitive device may include: the control unit 6 generates a trigger signal according to an input or automatically generated instruction, sends the trigger signal to the data reading circuit 5, and the data reading circuit 5 reads the light intensity information of all pixels on the photosensitive device 3 according to the trigger signal and stores the light intensity information in a storage unit.

According to an embodiment of the present invention, the data reading circuit 5 may specifically include an amplifying circuit and a sampling circuit. The amplifying circuit can amplify weak electric signals by 10 to 100 times in an electronic gain mode. The sampling circuit can carry out digital sampling on the electronic signal to obtain a signal numerical value of light intensity.

Finding the peak position P of the light intensity corresponding to each wavelength in the light intensity information, and marking the peak position P as P₁,P₂,…,P_MThe step (b) may comprise: the acquired light intensity signal values of all the pixels are expressed as G ═ G by a one-dimensional array G₁,g₂,...,g_k]And k is the number of pixels, the change interval of the array G is divided according to the wavelength type of the light emitted by the multicolor light source, and the position of the maximum value in each interval is determined as the peak position P.

According to the Cauchy's dispersion formula, the total reflection angle theta and the peak value P_MThe calculation of the refractive index of the liquid corresponding to the different wavelengths may comprise the steps of:

a light beam emitted from the LED light source is incident on the triangular prism 2 at a certain angle, and is totally reflected on the upper surface thereof, and according to snell's law of reflection, the following relationship exists between the angle of reflection and the refractive index:

n₂＝n₁*sin(θ) (1)

where θ is the angle of reflection, n₁Is the refractive index of the prism, n₂Is the refractive index of the liquid to be measured, sin () represents a sine function;

the cauchy dispersion formula states that the refractive index varies with wavelength:

n(λ)＝A+B/λ²+C/λ⁴ (2)

where n is the refractive index, λ is the wavelength of the light, and a, B and C are constants, e.g., according to one embodiment of the present invention, a is 1.3839 and B is-16.11 × 10^-3,C＝5.16×10^-3。

According to the formula (1) and the formula (2), it can be deduced that light rays with different wavelengths enter from one side of the triple prism, are reflected by the upper surface of the triple prism and then exit from the other side of the triple prism, the angle of the exiting light rays changes along with the wavelength, and the exiting light rays can fall on different positions of the photosensitive device.

For example, if the photosensitive device is a linear CCD array, the arrangement direction of its pixels is the direction depicted in fig. 1. As shown in fig. 1, three different wavelengths of light, i.e., blue, yellow, and red, are dispersed at different positions of the linear CCD. If a focusing lens 7 is placed in its vicinity, light of the same wavelength will be focused on some pixels. All the pixel signal intensities are read out by the data read circuit 5, and a waveform as shown in fig. 2 is formed.

Assuming that the total number of pixels of the linear CCD is 100, the light intensity output of all pixels can be expressed by a one-dimensional array G, i.e., G ═ G₁,g₂,...,g₁₀₀]。

As shown in FIG. 2, the blue light, the yellow light and the red light form 3 peak positions on the light intensity signal curve, respectively at P₁、P₂、P₃. From the position of the peak, the angle θ of total reflection can be deduced:

sin(θ)＝f(P) (3)

f represents the sine of the angle of total reflection sin (θ) as a function of the peak position P. This functional relationship is complex and difficult to express with a general formula. From the measured data, it is shown that, in the usual range, f can be fitted with an approximately linear relationship: f (x) a x + c.

The values of a and c depend on the geometrical relationship between the prism, lens and linear CCD, and according to one embodiment of the present invention, a is 0.0017 and c is 0.9265.

Combining formula (1) to formula (3) yields:

n_j＝(A+B/λ²+C/λ⁴)*f(P_j) (4)。

λ is wavelength, j ═ 1, or 2, or 3, each representing one of blue, yellow, and red light, and n is_jIndicating the refractive index at a certain wavelength.

According to empirical formula, the refractive index is related to the concentration of liquid (weight of soluble solids divided by total weight of liquid) as follows:

c＝k*n+b (5)

where c is the concentration of the liquid and k and b are constants. K and b may vary for different wavelengths. For example, for red light (650nm), k-6.056, b-8.033; for yellow light (580nm), k is 5.657, b is-7.570; for blue light (440nm), k is 5.151 and b is-6.960.

Assuming 3 different wavelengths, the liquid concentration calculated for the different wavelengths is expressed as:

c＝(∑k_j*n_j+b_j)/3 (6)

Σ denotes the sum, j ranges from 1 to 3, representing 3 different wavelengths respectively.

The multispectral detection method adopts a multispectral mode to measure, and calibrates the refractive index measured by light rays with different wavelengths according to a Cauchy dispersion formula, thereby obtaining a more accurate result. The method can solve the problem that a single wavelength cannot adapt to different liquids. Meanwhile, the interference of ambient light can be reduced by measuring multiple wavelengths.

According to another aspect of the present invention, there is provided a multispectral detection system for detecting the content of soluble solids in a liquid, comprising a polychromatic light source 1, a triangular prism 2, a photosensitive device 3;

the multicolor light source 1 is arranged on one side of the triangular prism 2, emission light of the multicolor light source is projected to a critical surface of the triangular prism and liquid to be measured, the photosensitive device 3 is arranged on the other side of the triangular prism 2, the emission light is projected to the photosensitive device 3 through reflection light reflected by the critical surface, the photosensitive device 3 is connected with a data reading circuit 5 and used for obtaining light intensity information of all pixels on the photosensitive device, and the reading circuit 5 and the multicolor light source 1 are both connected to a control unit 6;

the control unit 6 comprises an instruction input/generation module 61, a trigger signal generation module 62, a storage module 63, a calculation module 64, a display module 65 and a control module 66;

the instruction input/generation module 61 is used for receiving or generating a control instruction; the trigger signal generating module 62 is configured to generate a trigger signal according to the control instruction and send the trigger signal to the multicolor light source1, or the data reading circuit 5; the storage module 63 is used for storing data; the calculating module 64 is configured to find a peak position P of the light intensity corresponding to each wavelength in the light intensity information, where the peak position P is marked as P₁,P₂,…,P_MWherein M is the number of wavelengths in the spectrum, according to the Cauchy dispersion formula, the total reflection angle theta and the peak value P_MCalculating the refractive index of the liquid corresponding to different wavelengths according to the formula c ═ k × n + b, wherein c is the concentration of the liquid, k and b are constants for specific wavelengths, and taking the average value of the liquid concentrations corresponding to different wavelengths as the measured liquid concentration; the display module 65 is used for displaying the refractive index and/or concentration value; the control module 66 is used for controlling the above modules.

The bottom of the prism 2 can also be provided with a slot for placing a light-shielding plate 21, which is called as a diaphragm, and the size of the slot is consistent with the size of the diaphragm. The diaphragm is made of a light-tight material and is rectangular or triangular in shape, and the function of the diaphragm is to prevent light emitted by the light source from directly entering the photosensitive device 3.

According to a further aspect of the present invention there is provided a computer readable storage medium having stored therein at least one instruction, at least one program, set of codes or set of instructions, which is loaded and executed by a processor to carry out the operations carried out in the method of multi-spectral detection of soluble solids content in a liquid as described above.

The readable storage medium may be a flash memory, a hard disk, a multimedia card, a card type memory (e.g., SD or DX memory, etc.), a magnetic memory, a magnetic disk, an optical disk, etc. The storage module 63 stores at least one instruction, at least one program, set of codes, or set of instructions that are loaded and executed by the processor to implement the operations performed in the above method. The processor communicates with the memory module through a communication bus and a network interface. The storage module includes at least one type of readable storage medium, which includes flash memory, a hard disk, a multimedia card, a card-type memory (e.g., SD or DX memory, etc.), a magnetic memory, a magnetic disk, an optical disk, and the like. The storage module may in some embodiments be an internal storage unit of the control unit 6, e.g. a hard disk. The memory module may also be an external memory device of the control unit 6 in other embodiments, such as a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash memory Card (Flash Card), etc. Further, the memory module may also include both an internal memory unit and an external memory device. The storage module may be used not only to store application software and various types of data, such as codes of data processing programs, etc., but also to temporarily store data that has been output or is to be output.

The control Unit 6 may be a Central Processing Unit (CPU), a controller, a microcontroller, a microprocessor or other data Processing chip in some embodiments, and is used for running program codes stored in the memory module or Processing data.

The embodiments in the above embodiments can be further combined or replaced, and the embodiments are only used for describing the preferred embodiments of the present invention, and do not limit the concept and scope of the present invention, and various changes and modifications made to the technical solution of the present invention by those skilled in the art without departing from the design idea of the present invention belong to the protection scope of the present invention.