CN117969427A - Optical attenuation reference sensor and optical attenuation compensation method thereof - Google Patents

Abstract

The invention provides a light attenuation reference sensor and a light attenuation compensation method thereof, which are recorded in the embodiment of the invention, wherein the light attenuation reference sensor comprises a shell and a probe arranged at one end of the shell, a scanning circuit board and a receiving circuit board are arranged in the shell, a scanning light source is arranged on the scanning circuit board, a measuring receiver is arranged at one end of the receiving circuit board, two symmetrical detecting bulges are arranged on the probe, the measuring receiver is positioned at the inner side of one detecting bulge, a light transmission structure is arranged near the two detecting bulges, and the scanning light source can irradiate on the measuring receiver through the light transmission structure of the other detecting bulge; the receiving circuit board is also provided with a compensating light receiver, and the scanning light source directly irradiates on the compensating light receiver. The invention has the following beneficial effects: the scanning light source is matched with the measuring receiver and the compensating light receiver, so that the technical problem that the detection accuracy of the sensor can be reduced after the service time is long in the existing optical water quality sensor is solved.

Description

Optical attenuation reference sensor and optical attenuation compensation method thereof

Technical Field

The invention relates to the technical field of water quality sensors, in particular to a light attenuation reference sensor and a light attenuation compensation method thereof.

Background

The optical water quality sensor is an advanced water quality monitoring technology, and the optical water quality sensor detects various components in water by utilizing the characteristics of light absorption, scattering, reflection and the like. Among them, fluorescence, absorption, raman, etc. are commonly used optical detection techniques. The method is based on different response characteristics of different substances to light with specific wavelength, and can quantitatively or qualitatively analyze parameters such as pollutants, dissolved oxygen, turbidity and the like in water by measuring the intensity change or spectral characteristics of the light.

However, because the light sources are adopted in actual use, the commonly used light sources at present are provided with components such as LEDs and the like to realize light emission, but the light sources have different proportions of light attenuation, namely light loss, along with different use time.

After the light source of the water quality sensor is subjected to light attenuation, the situation that the measured value is inaccurate is necessarily caused, and in order to avoid the situation, the relation between the light source light attenuation and time is tested in a data compensation mode, namely, when the water quality sensor is manufactured, then the tested data are used for carrying out time light attenuation compensation on the water quality sensor.

However, the compensation mode is only theoretical value compensation, and is inaccurate for the light attenuation condition of the water quality sensor in actual use, so that the light attenuation of the water quality sensor is accelerated or slowed down due to different environments and temperatures of the water quality sensor in actual use.

Disclosure of Invention

Aiming at the defects existing in the prior art, the invention provides a light attenuation reference sensor and a light attenuation compensation method thereof, which solve the technical problem that the detection accuracy of the sensor is reduced after the service time is long in the existing optical water quality sensor.

According to the embodiment of the invention, the optical attenuation reference sensor comprises a shell and a probe arranged at one end of the shell, wherein a scanning circuit board and a receiving circuit board are arranged in the shell, a scanning light source is arranged on the scanning circuit board, a measuring receiver is arranged at one end of the receiving circuit board, two symmetrical detecting bulges are arranged on the probe, the measuring receiver is positioned at the inner side of one detecting bulge, a light transmission structure is arranged near the two detecting bulges, and the scanning light source can irradiate on the measuring receiver through the light transmission structure of the other detecting bulge; the receiving circuit board is also provided with a compensating light receiver, and the scanning light source directly irradiates on the compensating light receiver.

The technical principle of the invention is as follows: the light of the scanning light source passes through one inspection bulge and passes through the water sample, then enters the other inspection bulge, the data are measured after the light is received by the measuring receiver, meanwhile, the light of the scanning light source is directly received by the compensating light receiver to obtain the data, then the data of the measuring receiver are compensated in real time by adopting the data of the compensating light receiver, and the measured water quality data of the sensor are ensured to be always accurate.

Compared with the prior art, the invention has the following beneficial effects: the scanning light source is matched with the measuring receiver and the compensating light receiver, so that the technical problem that the detection accuracy of the sensor can be reduced after the service time is long in the existing optical water quality sensor is solved.

Further, two scanning light sources are arranged, one scanning light source is arranged on the inner side of the other detection protrusion and is symmetrical to the measurement receiver; the other scanning light source and the compensating light receiver are symmetrically arranged.

I.e. two scanning light sources are actually used, but because the two scanning light sources are in the same environment, the degree of light decay should be equal.

Further, the scanning light source is provided with one, the scanning light source is connected with the measuring receiver and the measuring receiver through Y-shaped optical fibers, the scanning light source is aligned with the common end of the Y-shaped optical fibers, one branch end of the Y-shaped optical fibers is aligned with the measuring receiver through a light transmission structure, and the other branch end of the Y-shaped optical fibers is directly aligned with the compensating light receiver.

A scanning light source is matched with Y-shaped optical fibers, so that the scanning light source irradiates the measuring receiver and the compensating light receiver simultaneously, and the light attenuation degree can be measured absolutely and accurately.

Further, one end of the probe is in threaded sealing connection with the shell, the other end of the probe and one detection protrusion are directly integrally formed, the probe is fixedly and hermetically connected with the other detection protrusion, and a communicated channel is arranged between the probe and the other detection protrusion.

One detection bulge and probe integrated into one piece have guaranteed its absolute waterproof performance, and another is for the dismouting demand, design as disconnect-type.

Further, two detection protrusions are arranged on one side, close to each other, of each detection protrusion, the light-transmitting structure is a glass sheet, and the glass sheet is fixed on the detection opening.

Further, the probe is internally provided with a T-shaped block, two ends of the T-shaped block are provided with fixing plates, and the scanning circuit board and the receiving circuit board are respectively fixed on the two fixing plates.

The scanning circuit board and the receiving circuit board are in a parallel state, so that the measuring receiver and the compensating light receiver can receive the light of the scanning light source conveniently.

Further, the control module: the scanning light source, the measuring receiver and the compensating light receiver are controlled to work in a connecting way;

and a communication module: the communication control module is used for communicating with the upper computer;

the receiving circuit board includes:

And a data processing module: the data processing module is connected with the control module and the data processing module, and the data processing module transmits the calculation result to the upper computer through the control module.

The control module is separated from the data processing module, different chips are adopted, one chip is guaranteed to only need operation, the other chip is responsible for control, and compared with the chip, the control module has the advantages that the requirement on the performance of the chip is greatly reduced, and errors are not easy to occur in operation.

Further, the control module is also connected with a temperature detection module for detecting the temperature of the water sample; the temperature detection module is arranged at the center of the probe and is positioned between the two detection protrusions.

For detecting the temperature of the water sample, and then the data detected by the measuring receiver can be compensated.

Furthermore, the receiving circuit board is also provided with a storage module, and the data processing module is connected with the storage module.

The temporary storage detection data of the storage module is set, so that the problem of the communication module in communication is avoided, and the data can be called out again from the storage module.

The light attenuation compensation method of the light attenuation reference sensor according to the embodiment of the invention is characterized in that: comprising the following steps:

s1, calibrating and measuring: measuring in the calibration liquid, wherein the detection data obtained by the measurement receiver is reference detection data;

S2, actual measurement; measuring in a water sample, wherein the detection data obtained by a measuring receiver is water quality detection data, and the detection data obtained by a compensating light receiver is compensating detection data;

S3, pre-calculation: and (3) calculating the detection data in the steps S1 and S2 to obtain pre-calculated water quality data, wherein the formula is as follows: pre-calculated water quality data = water quality detection data reference detection data/compensation detection data;

S4, secondary calculation: and (3) calculating the pre-calculated water quality data of the step (S3) again to obtain final water quality data, wherein the formula is as follows: final water quality data = 1g (reference detection data/pre-calculated water quality data)/solution absorption coefficient/solution layer thickness.

1. The purpose in the step S1 is to record the factory light intensity of the scanning light source, so that the service time of the sensor can be calculated.

2. In the step S3, accurate light attenuation compensation can be performed through the calculation formula, and the following steps are ensured: the accuracy of the water quality data is pre-calculated.

3. And S4, calculating an accurate predicted value as water quality data according to the formula in the step.

Drawings

Fig. 1 is a schematic diagram of the optical attenuation reference sensor according to embodiment 1 of the present invention.

Fig. 2 is a schematic diagram of the probe structure of embodiment 1 of the present invention.

Fig. 3 is a block diagram showing the structure of an optical attenuation reference sensor according to embodiment 1 of the present invention.

Fig. 4 is a step diagram of a light attenuation compensation method according to embodiment 1 of the present invention.

Fig. 5 is a schematic diagram of the structure of an optical attenuation reference sensor in embodiment 2 of the present invention.

In the above figures: 100. a housing; 200. a probe; 210. detecting the bulge; 211. a channel; 220. a light-transmitting structure; 221. a detection port; 222. a glass sheet; 230. a T-shaped block; 231. a fixing plate; 300. scanning the circuit board; 310. scanning a light source; 311. y-shaped optical fiber; 400. a receiving circuit board; 410. a measurement receiver; 420. compensating for the optical receiver.

Detailed Description

The technical scheme of the invention is further described below with reference to the accompanying drawings and examples.

Example 1

The optical attenuation reference sensor shown in fig. 1 comprises a housing 100 and a probe 200 arranged at one end of the housing 100, wherein a scanning circuit board 300 and a receiving circuit board 400 are arranged in the housing 100, two symmetrical detection protrusions 210 are arranged on the probe 200, the position between the two detection protrusions 210 is used for water sample to pass through, and a light transmission structure 220 is arranged at the position, close to the two detection protrusions 210, for detection.

One end of the receiving circuit board 400 is provided with a measuring receiver 410, the measuring receiver 410 is positioned at the inner side of one inspection protrusion, the receiving circuit board 400 is also provided with a compensating light receiver 420, and the scanning circuit board 300 is provided with two scanning light sources 310; one of the scanning light sources 310 is disposed inside the other detection protrusion 210 and is symmetrical to the measurement receiver 410, so that the scanning light source 310 can irradiate the measurement receiver 410 through the light-transmitting structure 220 of the other detection protrusion 210 to realize detection of a water sample; the other scanning light source 310 is symmetrically arranged with the compensating light receiver 420, so that the scanning light source 310 is ensured to directly irradiate on the compensating light receiver 420, and light attenuation detection of the scanning light source 310 is realized.

As shown in fig. 2, one end of the probe 200 is in threaded sealing connection with the housing 100, the other end of the probe 200 is directly integrally formed with one detection protrusion 210, the probe 200 is fixedly and hermetically connected with the other detection protrusion 210, a communicating channel 211 is arranged between the probe 200 and the other detection protrusion 210, the channel 211 is used for receiving a measuring receiver 410 on the circuit board 400, and the measuring receiver can be mounted on the inner side of the detection protrusion 210.

As shown in fig. 2, a detection opening 221 is formed on one side of the two detection protrusions 210, which is close to each other, and the light-transmitting structure 220 is a glass sheet 222, and the glass sheet 222 is fixed on the detection opening, so as to ensure that the light energy of the scanning light source 310 passes through.

As shown in fig. 1, a T-shaped block 230 is screwed on the inner side of the probe 200, fixing plates 231 are screwed on both ends of the T-shaped block 230, and the scan circuit board 300 and the receiving circuit board 400 are respectively fixed on the two fixing plates 231, so that the scan circuit board 300 and the receiving circuit board 400 are ensured to be parallel to each other, and the two scan light sources 310 can accurately irradiate on the measurement receiver 410 and the compensation light receiver 420 respectively.

As shown in fig. 3, the scanning circuit board 300 in the light-decay reference sensor includes;

and the control module is used for: the connection controls the operation of the scanning light source 310, the measuring receiver 410 and the compensating light receiver 420, that is, only controls the operation of the scanning light source 310, the measuring receiver 410 and the compensating light receiver 420, and does not perform data receiving and calculating.

And a communication module: the optical attenuation control system is used for the communication control module and the upper computer, namely the control module can receive instructions of the upper computer and can also send data and feed back the optical attenuation reference sensor condition to the upper computer.

The receiving circuit board 400 includes:

And a data processing module: the data processing module only performs the calculation of the data and does not control the operation of the receiving measurement receiver 410 and the compensating optical receiver 420. The control module and the data processing module are connected with each other, the data processing module transmits the calculation result to the upper computer through the control module, namely, the control module and the data processing module are mutually independent control chips, and the control module and the data processing module are not mutually controlled and only mutually perform data transmission.

As shown in fig. 3, the control module is also connected with a temperature detection module for detecting the temperature of the water sample; the temperature detection module is arranged in the center of the probe 200 and is positioned between the two detection protrusions 210, namely, the temperature of the water sample is detected by the temperature detection module, and the data is directly transmitted to the upper computer by the control module.

As shown in fig. 3, a storage module is further disposed on the receiving circuit board 400, and the data processing module is connected with the storage module, so that the calculation result can be temporarily stored in the storage module, and even if errors and anomalies occur in the light attenuation reference sensor, the light attenuation reference sensor can still acquire data through the storage module.

As shown in fig. 4, the optical attenuation compensation method of the optical attenuation reference sensor includes:

S1, calibrating and measuring: the measurement is performed in the calibration fluid, and the detection data obtained by the measurement receiver 410 is reference detection data.

S2, actual measurement; the measurement is performed in the water sample, the detection data obtained by the measurement receiver 410 is water quality detection data, and the detection data obtained by the compensation light receiver 420 is compensation detection data.

S3, pre-calculation: and (3) calculating the detection data in the steps S1 and S2 to obtain pre-calculated water quality data, wherein the formula is as follows: pre-calculated water quality data = water quality detection data reference detection data/compensation detection data, i.e. pre-calculated water quality data is data after light attenuation compensation.

S4, secondary calculation: and (3) calculating the pre-calculated water quality data of the step (S3) again to obtain final water quality data, wherein the formula is as follows: the final water quality data=1 g (reference detection data/pre-calculated water quality data)/solution absorption coefficient/solution layer thickness, and the formula of the secondary calculation can be used for calculation of a single spectrum method and calculation of multiple spectrums, and the accuracy of the obtained data is high.

Example 2

As shown in fig. 5, the difference between the present embodiment and embodiment 1 is that only one scanning light source 310 is provided, the scanning light source 310 is connected with the measuring receiver 410 and the measuring receiver 410 by using the Y-shaped optical fiber 311, and the specific scanning light source 310 is aligned with the common end of the Y-shaped optical fiber 311, one branch end of the Y-shaped optical fiber 311 is aligned with the measuring receiver 410 through the light-transmitting structure 220, and the other branch end of the Y-shaped optical fiber 311 is directly aligned with the compensating light receiver 420, so as to realize that one light source is aligned with the measuring receiver 410 and the compensating light receiver 420.

Compared with the embodiment 1, the embodiment has the problem that the arrangement difficulty of the Y-shaped optical fiber 311 is high, but because only one scanning light source 310 is used, compared with two scanning light sources 310, the embodiment has higher measurement accuracy of the light attenuation of the scanning light sources 310, and the situation of inaccurate light attenuation measurement cannot necessarily occur.

Experimental example 1

The light-decay reference sensor of example 1 was used and the two scanning light sources were identical LED light sources.

Experimental example 2

The light-decay reference sensor of example 1 was used, but the two scanning light sources were LED light sources of different quality.

Experimental example 3

The light-decay reference sensor of example 2 was used.

Comparative example 1

The same sensor as in experimental example 1 was used, but without the compensating light receiver, the step S3 was not performed.

The sensors of experimental examples 1-3 and comparative example 1 were used in different ways, and water samples with different COD concentration values were measured to obtain the following experimental data:

use is often 0 days:

Actual value	Experimental example 1	Experimental example 2	Experimental example 3	Comparative example 1
					0	0	0	0	0
5	5.15	5.2	5.2	5.1
					10	10.2	10.5	10.2	10.6
20	20.3	20.4	20.1	20.3
					50	50.5	50.6	50.4	50.4
100	101.3	101.5	101.1	101.7

Use is often 3 months:

Actual value	Experimental example 1	Experimental example 2	Experimental example 3	Comparative example 1
					0	0	0	0	0
5	5.1	5.3	5.1	4.8
					10	10.1	10.3	10.2	9.7
20	20.2	20.1	20.1	19.8
					50	50.7	50.5	50.5	49.6
100	101.4	101.4	101.3	98.7

Use is often 1 year:

as can be seen from the above table, the data accuracy is far higher in the case of experimental example 1 than in the case of experimental example 3 at the time of 3 months and the time of 1 year, whereas in the case of experimental example 2, the exact start of the degradation is decreased in the case of one year of use period due to the different quality of the scanning light source.

Finally, it is noted that the above embodiments are only for illustrating the technical solution of the present invention and not for limiting the same, and although the present invention has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made thereto without departing from the spirit and scope of the technical solution of the present invention, which is intended to be covered by the scope of the claims of the present invention.

Claims (10)

1. A light attenuation reference sensor, characterized by: the probe comprises a shell and a probe arranged at one end of the shell, wherein a scanning circuit board and a receiving circuit board are arranged in the shell, a scanning light source is arranged on the scanning circuit board, a measuring receiver is arranged at one end of the receiving circuit board, two symmetrical detecting protrusions are arranged on the probe, the measuring receiver is positioned at the inner side of one detecting protrusion, a light transmission structure is arranged near the two detecting protrusions, and the scanning light source can irradiate on the measuring receiver through the light transmission structure of the other detecting protrusion; the receiving circuit board is also provided with a compensating light receiver, and the scanning light source directly irradiates on the compensating light receiver.

2. The optical attenuation reference sensor of claim 1, wherein: the two scanning light sources are arranged, one scanning light source is arranged on the inner side of the other detection protrusion and is symmetrical to the measurement receiver; the other scanning light source and the compensating light receiver are symmetrically arranged.

3. The optical attenuation reference sensor of claim 1, wherein: the scanning light source is provided with one, the scanning light source is connected with the measuring receiver and the measuring receiver through Y-shaped optical fibers, the scanning light source is aligned with the common end of the Y-shaped optical fibers, one branch end of the Y-shaped optical fibers is aligned with the measuring receiver through a light transmission structure, and the other branch end of the Y-shaped optical fibers is directly aligned with the compensating light receiver.

4. A light-decay reference sensor according to any of claims 1-3, wherein: one end of the probe is in threaded sealing connection with the shell, the other end of the probe is directly integrally formed with one detection protrusion, the probe is fixedly and hermetically connected with the other detection protrusion, and a communicated channel is arranged between the probe and the other detection protrusion.

5. The optical attenuation reference sensor of claim 4, wherein: two detect protruding one side that is close to each other is equipped with the detection mouth, the light-transmitting structure is the glass piece, the glass piece is fixed on the inspection mouth.

6. The optical attenuation reference sensor of claim 1, wherein: the probe is characterized in that a T-shaped block is arranged on the inner side of the probe, fixing plates are arranged at two ends of the T-shaped block, and the scanning circuit board and the receiving circuit board are respectively fixed on the two fixing plates.

7. The optical attenuation reference sensor of claim 1, wherein:

The scanning circuit board includes;

And the control module is used for: the scanning light source, the measuring receiver and the compensating light receiver are controlled to work in a connecting way;

and a communication module: the communication control module is used for communicating with the upper computer;

the receiving circuit board includes:

And a data processing module: the data processing module is connected with the control module and the data processing module, and the data processing module transmits the calculation result to the upper computer through the control module.

8. The optical attenuation reference sensor of claim 7, wherein: the control module is also connected with a temperature detection module for detecting the temperature of the water sample; the temperature detection module is arranged at the center of the probe and is positioned between the two detection protrusions.

9. The optical attenuation reference sensor of claim 7, wherein: and the receiving circuit board is also provided with a storage module, and the data processing module is connected with the storage module.

10. The light-attenuation compensation method of a light-attenuation reference sensor according to claim 1, wherein: comprising the following steps:

s1, calibrating and measuring: measuring in the calibration liquid, wherein the detection data obtained by the measurement receiver is reference detection data;

S2, actual measurement; measuring in a water sample, wherein the detection data obtained by a measuring receiver is water quality detection data, and the detection data obtained by a compensating light receiver is compensating detection data;

S3, pre-calculation: and (3) calculating the detection data in the steps S1 and S2 to obtain pre-calculated water quality data, wherein the formula is as follows: pre-calculated water quality data = water quality detection data reference detection data/compensation detection data;

S4, secondary calculation: and (3) calculating the pre-calculated water quality data of the step (S3) again to obtain final water quality data, wherein the formula is as follows: final water quality data = 1g (reference detection data/pre-calculated water quality data)/solution absorption coefficient/solution layer thickness.