A mixed chemical concentration measuring instrument and a measuring method thereof with diagnosis

Abstract

This invention relates to the field of liquid chemical measurement, and discloses a mixed chemical concentration measuring instrument and its diagnostic measurement method, comprising the following steps: emitting and enhancing light in a specific spectral band using a halogen lamp and a cold light source; achieving multi-beam coupling, common-path transmission, common-path transmission, and common-path reception through a multimode fiber coupler, a first multimode fiber, a light transmitter, and a light receiver; storing a reference spectrum in the main control board's memory for detecting light source performance degradation, pipeline contamination, and unknown chemical substances, thus enabling instrument self-diagnosis; measuring the chemical concentration using a specific light source wavelength band, comparing the measurement result with the data points of the reference spectrum; if the measurement result shows a decrease in the amplitude of the detection signal compared to the reference spectrum, it indicates a fault in the equipment or the presence of bubbles or impurities in the chemical being measured; triggering an alarm if an abnormality occurs, otherwise completing the concentration measurement through the main control board and the spectral analysis module. This invention enables instrument self-diagnosis when measuring chemical concentration, thereby eliminating various faults, allowing for early diagnostic operations and manual maintenance, and ensuring the accuracy of the test results.

Description

[0001] This application is a divisional application of the invention patent application with application number CN202310333738.9, application date March 31, 2023, entitled "A mixed chemical concentration measuring instrument and a measurement method with diagnostic capabilities thereof". Technical Field

[0002] This invention belongs to the field of liquid chemical measurement, and more specifically, relates to a measurement method with diagnostic function for an online real-time instrument for measuring the concentration of mixed chemicals. Background Technology

[0003] Currently, industries such as semiconductor manufacturing, solar energy manufacturing, and LED manufacturing require online, real-time concentration monitoring and measurement of liquid chemicals during production to ensure stable product quality and improved yield. For single-component chemicals, density or refractive index methods are generally used for measurement. However, for mixed multi-component chemicals, these methods cannot distinguish changes in the individual components. These measurement methods lack specificity and are also affected by solution turbidity, bubbles, and solid particulate impurities.

[0004] This invention enhances a specific spectral band by employing a highly stable cold light source. It utilizes a multimode fiber coupler, a first multimode fiber, an optical transmitter, and an optical receiver to achieve multi-beam coupling, common-path transmission, and common-path transmission and reception, thereby improving the signal-to-noise ratio of the detected signal in that specific spectral band. A reference spectrum is stored in the instrument's main control board's memory for detecting and warning of light source performance degradation, pipeline contamination, and the presence of unknown chemicals in liquid mixtures. This enables intelligent self-diagnosis of the instrument, improving the measurement accuracy of multiple chemical concentrations while simultaneously reducing the cost of the measuring instrument. It can meet the requirements of in-situ and online measurement accuracy, and adapt to solutions with turbidity, bubbles, and impurities.

[0005] Furthermore, when measuring chemical concentrations, inaccurate results are often caused by equipment malfunctions (e.g., light source failure, contamination or blockage of the transmitter or receiver ports) or the presence of bubbles or impurities in the chemical itself. Therefore, to eliminate measurement inaccuracies caused by instrument malfunctions or chemical contamination, a diagnostic step should be added before using the instrument to measure chemical concentrations. If the diagnostic results indicate an abnormality, manual maintenance or treatment of the chemical should be performed before resuming the test. Summary of the Invention

[0006] The purpose of this invention is to provide a mixed chemical concentration measuring instrument and a diagnostic measurement method thereof, which improves the performance of the method. When measuring chemical concentration, the measuring instrument can perform self-diagnosis, thereby ensuring that various faults can be eliminated, allowing for early diagnosis and manual maintenance, and ensuring the accuracy of the test results.

[0007] The specific technical solution adopted by this invention is as follows:

[0008] A measurement method for a measuring instrument includes a main control board and light emitting and light receiving ends located on both sides of a target liquid chemical. The output end of the main control board is connected to a plurality of light sources. One end of each of the light sources is equipped with a multimode fiber coupler via a pigtail, and the other end of the multimode fiber coupler is provided with a light emitting end. The light emitting end and the light receiving end are correspondingly arranged. The output end of the light receiving end is connected to a spectral analysis module. One end of the multimode fiber coupler is equipped with a first multimode fiber, and the other end of the first multimode fiber is installed at the input end of the light emitting end.

[0009] Optionally, a second multimode fiber is fixedly installed at the output end of the optical receiver, and the other end of the second multimode fiber is fixedly installed at the input end of the spectral analysis module.

[0010] Optionally, a liquid chemical flow channel is provided between the light emitting end and the light receiving end, and a temperature sensor is fixedly installed on the side wall of the liquid chemical flow channel.

[0011] Optionally, the light source includes halogen lamps and / or cold light sources.

[0012] An instrument for measuring the concentration of mixed chemicals and a diagnostic measurement method thereof, comprising the following steps:

[0013] S1. Halogen lamps are used to emit light in the conventional spectral range, and a highly stable cold light source is used to enhance the light in a specific spectral range.

[0014] S2. Through a multimode fiber coupler, a first multimode fiber, an optical transmitter, and an optical receiver, a method is achieved for multi-beam optical coupling, common-path transmission, and common-path transmission and reception.

[0015] S3. Store reference spectra in the memory of the instrument's main control board for the detection and early warning of light source performance degradation, pipeline contamination, and the presence of unknown chemical substances in liquid mixed chemicals, thereby realizing the instrument's intelligent self-diagnosis.

[0016] S4. The concentration of chemicals is measured using a specific light source wavelength. The measurement results are compared with multiple data points of the reference spectrum. If the measurement results show a decrease in energy compared with the reference spectrum, it indicates that the equipment is faulty or that the chemical being tested contains bubbles or impurities.

[0017] S5. If an abnormality occurs during the measurement process, the measuring instrument will control the alarm to sound through the main control board; if no abnormality occurs, the main control board and the spectral analysis module will perform the measurement operation of the concentration of the chemical to be tested.

[0018] Optionally, S1 can be a wavelength-selective cold light source based on the characteristic spectrum of the chemical to be tested.

[0019] Optionally, the reference spectrum mentioned in S3 may be either the measurement spectrum of deionized water or the measurement spectrum of a mixture of chemicals.

[0020] Optionally, the reference spectrum mentioned in S3 can be either operated by the user in the instrument calibration program or set by the instrument manufacturer.

[0021] Optionally, in S4, the test solution is compared based on the wavelength at which the chemical composition of the test chemical does not absorb light, using this wavelength as the data point.

[0022] Optionally, in S4, based on the selected data points, when all measurement results are less than the detection signal amplitude of the reference spectrum, it is predicted that the light source energy of the measuring instrument has decreased; when individual data points in the measurement results decrease, it is predicted that the solution to be tested contains impurities.

[0023] Optionally, to determine whether the alarm is caused by a malfunction of the measuring instrument, deionized water can be used for testing. If no alarm is triggered after testing with deionized water, the measuring instrument can be determined to be fault-free.

[0024] Optionally, an alarm can be triggered to determine if the problem lies with the solution being tested. If the measuring instrument is replaced and the test is repeated, and no fault alarm is triggered after testing with the replaced measuring instrument, then the solution being tested is found to be without problems.

[0025] The technical effects achieved by this invention are as follows:

[0026] This method measures the concentration of mixed chemicals by emitting light signals using a cold light source. The signals pass through a multimode fiber coupler, a light transmitter, and a light receiver, with the transmitter and receiver positioned on opposite sides of the liquid containing the chemical. A reference spectrum is stored in the main control board's memory. This reference spectrum is used to detect and warn of light source performance degradation, pipeline contamination, and the presence of unknown chemicals in the mixed liquid. This achieves multi-beam coupling and common-path transmission. The chemical concentration is measured using a specific light source wavelength, and the results are compared with multiple points in the reference spectrum. A decrease in energy indicates a malfunction in the equipment or the presence of bubbles or impurities in the solution. If any abnormality occurs during the measurement process, the main control board triggers an alarm. If no abnormality is detected, the measurement proceeds, and the concentration is determined using a spectral analysis module connected to the main control board. This improves the method's performance. During chemical concentration measurement, the instrument can perform self-diagnosis, allowing for troubleshooting and early manual maintenance, thus ensuring the accuracy of the test results. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a schematic diagram of the structure of a mixed chemical concentration measuring instrument according to the present invention;

[0029] Figure 2 This is a flowchart of a diagnostic method for a mixed chemical concentration measuring instrument according to the present invention;

[0030] Figure 3 This diagram illustrates the abnormal factors in the hydrogen peroxide case of the present invention.

[0031] Figure 4 This diagram illustrates how the hydrogen peroxide solution of the present invention filters out abnormal factors.

[0032] Figure 5 This is a measurement spectrum diagram of the hydrogen peroxide example of the present invention.

[0033] Explanation of reference numerals in the attached diagram: 1. Main control board; 2. Cold light source; 3. Halogen lamp; 4. Multimode fiber coupler; 5. First multimode fiber; 6. Light transmitter; 7. Light receiver; 8. Liquid chemical flow channel; 9. Second multimode fiber; 10. Spectral analysis module; 11. Temperature sensor. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Please see Figures 1-2This invention provides a mixed chemical concentration measuring instrument, including a main control board 1 and light emitting ends 6 and light receiving ends 7 located on both sides of the target liquid chemical. The output end of the main control board 1 is connected to a plurality of cold light sources 2 and halogen lamps 3. One end of each of the cold light sources 2 and halogen lamps 3 is connected to a multimode fiber coupler 4 via a pigtail, and the other end of the multimode fiber coupler 4 is provided with a light emitting end 6, which is correspondingly positioned with the light receiving end 7. The output end of the light receiving end 7 is connected to a spectral analysis module 10. One end of the multimode fiber coupler 4 is equipped with a first multimode fiber 5, and the other end of the first multimode fiber 5 is installed at the input end of the light emitting end 6. A second multimode fiber 9 is fixedly installed at the output end of the light receiving end 7, and the other end of the second multimode fiber 9 is fixedly installed at the input end of the spectral analysis module 10. A liquid chemical flow channel 8 is provided between the light emitting end 6 and the light receiving end 7, and a temperature sensor 11 is fixedly installed on the side wall of the liquid chemical flow channel 8.

[0036] It should be noted that the cold light source 2 is a highly stable near-infrared light source, and a specific spectral band of light source is used to enhance the halogen lamp according to the type of chemical being tested, in order to improve the signal-to-noise ratio of the detection signal; a multimode fiber coupler 4 is also used. The system utilizes the energy exchange between waveguides in adjacent fiber core regions on different fiber surfaces. The optical transmitter 6 is the optical transmitter unit, used to send modulated optical signals in the optical transmission system. The optical receiver 7 is used to receive modulated optical signals in the optical transmission system. A spectral analysis module 10 is used to analyze the target spectrum. A reference spectrum is stored on the main control board 1 of the instrument. This reference spectrum is used for instrument self-diagnosis, for detecting and warning of light source performance degradation, pipeline contamination, and the presence of unknown chemical substances in liquid mixtures. The first multimode fiber 5 can transmit multiple optical transmission modes, ensuring that the optical signal emitted by the multimode fiber coupler 4 can be transmitted to the optical transmitter 6 via multiple channels. The optical transmitter 6 then transmits the modulated optical signal. A liquid chemical flow pipe 8 allows the optical transmitter 6 and optical receiver 7 to better detect the liquid flowing in it. A temperature sensor 11 is installed close to the optical transmitter and receiver to obtain accurate fluid temperature, which is then corrected by the main control board 1.

[0037] One of the diagnostic measurement methods for a mixed chemical concentration measuring instrument includes the following steps:

[0038] S1. A halogen lamp 3 emits light in the conventional spectral range, and a highly stable cold light source 2 enhances light in a specific spectral range. Specifically, the selection of the cold light source is based on the characteristic spectra of the chemical components in the analyte; for example, see [reference needed]. Figure 5In the measurement spectra of hydrogen peroxide at different concentrations, the detection signal amplitude of hydrogen peroxide is close to 0 at wavelengths greater than 1400nm. At this time, the signal-to-noise ratio is too low, so a cold light source greater than 1400nm can be selected for enhancement.

[0039] S2. By using a multimode fiber coupler 4, a first multimode fiber 5, an optical transmitter 6, and an optical receiver 7, the signal-to-noise ratio of the detected signal in a specific spectral band is improved by achieving multi-beam optical coupling, common-path transmission, common-path transmission, and common-path reception.

[0040] S3. Store the reference spectrum in the memory of the instrument's main control board 1 for the detection and early warning of light source performance degradation, pipeline contamination, and the presence of unknown chemical substances in liquid mixed chemicals, thereby realizing the instrument's intelligent self-diagnosis.

[0041] S4. The concentration of the chemical is measured using a specific light source wavelength band. The measurement result is compared with multiple data points of a reference spectrum. If the amplitude of the measured result decreases compared to the detection signal amplitude of the reference spectrum, it indicates that the equipment is faulty or that the solution to be tested contains bubbles or impurities. In some embodiments, based on selected data points, when all measurement results are less than the detection signal amplitude of the reference spectrum, it is presumed that the light source energy of the measuring instrument has decreased; when individual data points in the measurement results decrease, it is presumed that the solution to be tested contains impurities. In other embodiments, when selecting data points for comparison, they can be selected based on the chemical composition of the chemical to be tested; specifically, wavelengths where the chemical composition has no absorption are selected as reference points. For example, see [reference needed]. Figure 3 We selected wavelengths of 900nm, 958nm, 1145nm, and 1280nm, where hydrogen peroxide does not absorb light, as data points for comparison.

[0042] S5. If an abnormality occurs during the measurement process, the measuring instrument will control the alarm to sound through the main control board; if no abnormality occurs, the main control board 1 and the spectral analysis module 10 will be used to measure the concentration of the chemical to be tested.

[0043] In some embodiments, see Figure 2 In S3, the reference spectrum can be either the measurement spectrum of deionized water or the measurement spectrum of the analyte. Either the measurement spectrum of deionized water or the measurement spectrum of the analyte can be selected as the reference spectrum according to requirements. Furthermore, the reference spectrum in S3 can be set either by the user in the instrument calibration program or by the instrument manufacturer.

[0044] In some embodiments, see Figure 2In S4, the comparison points are determined based on the chemical composition of the analyte. For example, if the analyte solution contains three chemical components A, B, and C, then when selecting data points, points where these three chemical components absorb should be avoided. In other words, points that are unaffected should be selected. If these points absorb, it indicates an anomaly. By determining the comparison points based on the chemical composition of the analyte, it is convenient to compare the measurement results with multiple data points of the reference spectrum.

[0045] In some embodiments, see Figure 2 To determine whether the alarm is caused by a malfunction of the measuring instrument, use deionized water for further testing. If no alarm is triggered after testing with deionized water, the measuring instrument is found to be fault-free.

[0046] For further details, please refer to the following: Figure 2 The system determines whether the problem lies with the solution being tested and generates an alarm. If the measuring instrument is replaced and the test is repeated, and no fault alarm is triggered after testing with the replaced measuring instrument, then the solution being tested is found to be without problems.

[0047] In this invention, the main control board, multimode fiber coupler, optical transmitter, optical receiver, spectral analysis module, and temperature sensor are known components and will not be described in detail here.

[0048] Among them, see Figures 3-4 Taking the measurement data of hydrogen peroxide under abnormal and normal conditions as an example, if there is an instrument malfunction, the value of the test solution will deviate significantly. Therefore, adding this diagnostic step can effectively improve the accuracy of the test data.

[0049] The working process and principle of this invention are as follows: During use, in addition to using halogen lamps to provide the conventional wavelength band, in the wavelength band with low signal-to-noise ratio, a highly stable cold light source 2 is used to enhance the specific spectral band. By setting up a multimode fiber coupler 4, a first multimode fiber 5, an optical transmitter 6, and an optical receiver 7, multi-beam optical coupling, common-path transmission, common-path transmission, and common-path reception are achieved, thereby improving the signal-to-noise ratio of the detected signal in the specific spectral band. A reference spectrum is stored in the memory of the instrument's main control board 1 for use in situations such as light source performance degradation, pipeline contamination, and the presence of unknown chemicals in liquid mixtures. The instrument enables quality detection and early warning, achieving intelligent self-diagnosis and thus improving the measurement accuracy of multiple chemical concentrations. It measures chemical concentrations using a specific light source wavelength and compares the measurement results with multiple data points of a reference spectrum. If the amplitude of the measured signal decreases or the energy decreases compared to the reference spectrum, it indicates that the equipment is faulty or that the solution to be tested contains bubbles or impurities. If an abnormality occurs during the measurement process, the measuring instrument controls the alarm to sound through the main control board 1. If no abnormality occurs, the main control board 1 and the spectral analysis module 10 perform the measurement operation of the mixed chemical concentration.

[0050] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. A mixed chemical concentration measuring instrument and a diagnostic measuring method thereof, characterized in that: Includes the following steps: S1. A number of halogen lamps (3) connected to the output of the main control board (1) emit light in the conventional spectral range. A number of highly stable cold light sources (2) are selected according to the wavelength of the characteristic spectrum of the chemical to be tested. The cold light sources (2) connected to the output of the main control board (1) are used to enhance the specific spectral range. S2. Through the multimode fiber coupler (4) installed at one end of the halogen lamp (3) and the cold light source (2) via a pigtail, the first multimode fiber (5) installed at the other end of the multimode fiber coupler (4), and the light transmitter (6) which is correspondingly set on both sides of the liquid chemical flow pipe (8), with its input end connected to the other end of the first multimode fiber (5) and its output end fixedly connected to the second multimode fiber (9), multi-beam optical coupling, common path transmission, common path transmission and reception are realized. S3. Store the reference spectrum in the memory of the instrument main control board (1) for the discovery and early warning of light source performance degradation, pipeline contamination and the presence of unknown chemical substances in liquid mixed chemicals, so as to realize the instrument's intelligent self-diagnosis. S4. The concentration of chemicals is measured using a specific light source wavelength. A temperature sensor (11) is fixedly installed on the side wall of the liquid chemical flow pipe (8). The temperature sensor (11) is installed close to the light emitting end (6) and the light receiving end (7) to detect the fluid temperature. The detection signal is corrected by the main control board (1). The measurement result is compared with multiple data points of the reference spectrum. If the measurement result is lower than the detection signal amplitude of the reference spectrum, it indicates that the equipment is faulty or that the chemical to be tested contains bubbles or impurities. When the measurement results are all lower than the detection signal amplitude of the reference spectrum, it is predicted that the light source energy of the measuring instrument has decreased. When individual data points in the measurement result decrease, it is predicted that the solution to be tested contains impurities. S5. If an abnormality occurs during the measurement process, the measuring instrument will control the alarm to issue an alarm through the main control board; if no abnormality occurs, the measurement operation of the concentration of the chemical to be measured will be realized through the main control board (1) and the spectral analysis module (10) which is fixedly installed at the other end of the second multimode optical fiber (9) at the input end.

2. The mixed chemical concentration measuring instrument and its diagnostic measuring method according to claim 1, characterized in that: The reference spectrum mentioned in S3 is either the measurement spectrum of deionized water or the measurement spectrum of the chemical to be tested.

3. The mixed chemical concentration measuring instrument and its diagnostic measuring method according to claim 1, characterized in that: The reference spectrum mentioned in S3 is either one operated by the user in the instrument calibration program or set by the instrument manufacturer.

4. The mixed chemical concentration measuring instrument and its diagnostic measuring method according to claim 1, characterized in that: In S4, data points are compared based on the wavelengths at which the chemical components of the test chemical do not absorb light.

5. The mixed chemical concentration measuring instrument and its diagnostic measuring method according to claim 1, characterized in that: To determine whether the alarm is caused by a malfunction of the measuring instrument, test it again with deionized water. If no alarm is triggered after testing with deionized water, the measuring instrument is confirmed to be fault-free.

6. The mixed chemical concentration measuring instrument and its diagnostic measuring method according to claim 1, characterized in that: An alarm is triggered to determine if the problem lies with the solution being tested. If the measuring instrument is replaced and the test is repeated, and no fault alarm is triggered after testing with the replaced measuring instrument, then the solution being tested is not the problem.

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