An adaptive phosphorescence oxygen concentration measuring device and a measuring method thereof

Abstract

The application discloses a self-adaptive phosphorescence oxygen concentration measuring device and a measuring method thereof, and belongs to the technical field of phosphorescence oxygen concentration measurement. The application solves the problems that the existing room temperature phosphorescence method cannot realize continuous oxygen measurement in the range of 0-100% and the light bleaching influences the measurement precision. The application sets multiple oxygen probes with different sensitivities, so that the device can work without manual intervention and replacement of the oxygen probe. In combination with a light bleaching correction algorithm added in the measuring method, the phosphorescence intensity can be corrected in real time according to the measured oxygen concentration value and the known correction coefficient. In the case that the phosphorescence intensity is used as a relational parameter, the light bleaching correction can reduce the oxygen measurement error. The self-adaptive adjustment of the oxygen probe in the measuring process can realize the measurement of oxygen in the range of 0-100%, so that the sensor can be applied to an environment with a large change in oxygen concentration, the measurement precision is improved, and the service life of the sensor is prolonged.

Description

TECHNICAL FIELD

[0001] The present application relates to an adaptive phosphorescence oxygen concentration measuring device and a measuring method thereof, and belongs to the technical field of phosphorescence oxygen concentration measurement. BACKGROUND

[0002] Oxygen is one of the important substances for the survival of the earth, and the oxygen content in the environment affects the life activities of organisms, so it is very important to monitor the oxygen concentration in the environment. The existing oxygen measurement technologies mainly include the winkler titration method, the electrochemical detection method and the room temperature phosphorescence method. The winkler titration method is only suitable for the measurement of dissolved oxygen, the electrochemical sensor usually has a series of cross-sensitive gases which will affect the measurement of oxygen, and the room temperature phosphorescence method has the advantages of anti-electromagnetic interference and no oxygen consumption.

[0003] However, the existing room temperature phosphorescence method has the problems of single probe unable to respond to the change of oxygen in the range of 0-100% and light bleaching affecting the measurement accuracy. For the measurement of oxygen in the range of 0-100%, the existing room temperature phosphorescence method solution is to replace different oxygen probes according to the measurement range, which makes this method not suitable for oxygen monitoring in the environment with large concentration change. For light bleaching, the existing method generally adds reducing reagents in the probe to slow down the light bleaching, but the measurement accuracy of this method will gradually decrease over time.

[0004] In summary, in order to monitor the large change of oxygen in the environment and ensure the measurement accuracy of oxygen, it is necessary to provide an adaptive phosphorescence oxygen concentration measuring device and a measuring method thereof. SUMMARY

[0005] The present application provides an adaptive phosphorescence oxygen concentration measuring device and a measuring method thereof to solve the problems that the existing room temperature phosphorescence method cannot realize continuous oxygen measurement in the range of 0-100%, and light bleaching affects the measurement accuracy.

[0006] The technical method of the present application:

[0007] One of the purposes of the present application is to provide an adaptive phosphor oxygen concentration measuring device, which comprises an optical detection module and a control / signal processing module, and the optical detection module is a cuboid dark box separated into an upper cavity, a middle cavity and a lower cavity; 5 LED lamps 1 are arranged on the top of the upper cavity, a convex lens 2 and a beamsplitter 3 are arranged below each LED lamp 1 in sequence, the adjacent beamsplitters 3 are placed at different angles, a first detector 4 is arranged on the side wall of the upper cavity, and a short-wave pass filter 5 is arranged on the window of the first detector 4; the upper cavity and the middle cavity are separated by a light-blocking sealing plate 6, and the corresponding position of the LED lamp 1 on the light-blocking sealing plate 6 is a transparent partition plate 7, which has high visible light transmission characteristics. Oxygen probes 8 are arranged in the middle cavity corresponding to the positions of the LED lamps 1 in the upper cavity, the adjacent oxygen probes 8 have different sensitivities and placement angles, and a long-wave pass filter 9 and a convex lens 2 are arranged below each oxygen probe 8 in sequence, air inlet holes 14 and air outlet holes 15 are respectively formed on the opposite two side walls of the middle cavity; the middle cavity and the lower cavity are separated by a transparent sealing baffle 11, a second detector 12 is arranged at the bottom of the lower cavity, and a band-pass filter 13 is arranged on the window of the second detector 12;

[0008] The control / signal processing module comprises an electrical signal processing module, a power module and a micro-processing unit, the power module is connected with the electrical signal processing module, the micro-processing unit and the LED through an electrically controlled switch and supplies power, the electrical signal processing module is connected with the first detector and the second detector, the micro-processing unit controls the electrically controlled switch according to the set measurement program and processes the data obtained from the electrical signal processing module to give the oxygen concentration measurement result.

[0009] Further limited, the included angle between the beamsplitter 3 and the vertical line in the upper cavity from the end near the air inlet hole 14 is 55°, 60°, 65°, 75° and 80° in sequence.

[0010] Further limited, the air outlet hole 15 and the first detector 4 are located on the same inner side wall of the cuboid dark box.

[0011] Further limited, the air inlet hole 14 and the air outlet hole 15 are both provided with a filter screen.

[0012] Further limited, the power of the 5 LED lamps 1 is the same, and the light emitting wavelength of each LED lamp 1 is 405 nm.

[0013] Further limited, the included angle between the oxygen probe 8 and the vertical line in the middle cavity from the end near the air inlet hole 14 is 126°, 108°, 90°, 72° and 54° in sequence.

[0014] Further limited, the range of the oxygen probe 8 in the middle cavity from the end near the air inlet hole 14 is 0-0.05 kPa, 0.05-1 kPa, 1-5 kPa, 5-20 kPa and 20-100 kPa in sequence.

[0015] Further limited, the sensitivity of the oxygen probe 8 in the middle cavity from the end of the near air inlet 14 is 32.73 kPa -1 , 6.535 kPa -1 , 1.023 kPa -1 , 0.347 kPa -1 , and 0.076 kPa -1 .

[0016] Further limited, the distance between the LED lamp 1 and the convex lens 2 arranged below it is 30 mm.

[0017] Further limited, the vertical distance between the oxygen probe 8 and the convex lens 2 arranged below it is 30 mm.

[0018] Further limited, the short-wave pass filter 5 transmits wavelengths less than 450 nm.

[0019] Further limited, the long-wave pass filter 9 transmits wavelengths greater than 500 nm.

[0020] Further limited, the long-wave pass filter 9 is immediately below the corresponding oxygen probe 8.

[0021] Further limited, the band-pass filter 13 transmits wavelengths of 640-660 nm.

[0022] Further limited, the power module includes a 3.5V constant voltage source controlled by five electric switches to supply power to the five LED lamps 1.

[0023] Further limited, the power module also includes a 5V direct current power supply to supply power to the signal processing module and the microprocessor.

[0024] Further limited, the first detector 4 and the second detector 12 are both linear array CCD detectors.

[0025] Further limited, the five LED lamps 1 are placed in parallel and distributed along a straight line, and the straight line is perpendicular to the straight line on which the first detector 4 is located.

[0026] Further limited, the material of the transparent sealing baffle 11 is high-transmittance acrylic.

[0027] The second object of the present application is to provide a self-adaptive phosphorescent oxygen concentration measurement method, which uses the self-adaptive phosphorescent oxygen concentration measurement device described above, and the specific measurement method includes the following steps:

[0028] S1, the microprocessor unit controls the electrically controlled switch to supply power to the 4th LED lamp 1 from the near air inlet 14, the light emitted by the LED lamp 1 is converted into parallel light beams through the corresponding convex lens 2 below, the parallel light beams pass through the corresponding light splitter 3, a part of the parallel light beams transmits to the 4th oxygen probe from the near air inlet 14, so that the oxygen probe with a sensitivity of 0.347 kPa -1 works first, and then converges into the window of the second detector 12 through the convex lens 2 below the 4th oxygen probe, the other part is reflected into the window of the first detector 4 after passing through the short-wave pass filter 5, the LED lamp 1 continues to work for 3 s, and the oxygen concentration C0 is obtained based on the Stern-Volmer equation;

[0029] S2, according to the oxygen concentration C0 obtained in S1, the microprocessor unit controls the electrically controlled switch to make the LED lamp 1 corresponding to the oxygen probe 8 with an applicable range of the oxygen concentration C0 work;

[0030] S3, when the oxygen probe 8 works, the phosphorescence intensity value I p0 in the Stern-Volmer equation is corrected in real time by using formula 1;

[0031]

[0032] In the formula, K is a light bleaching correction coefficient obtained by the decay of phosphorescence with time under different oxygen concentrations, and t represents the working time, which is provided by the timing function of the microprocessor;

[0033] S4, when the oxygen concentration exceeds 5% of the range of the working oxygen probe 8, the corresponding LED lamp 1 is immediately turned off, and the LED lamp 1 corresponding to the oxygen probe 8 with an applicable range is automatically selected to work according to the results before the LED lamp 1 is turned off, and the correction function is also updated;

[0034] S5, S3 and S4 are repeated to enable the oxygen probe to measure in self-adaptive adjustment.

[0035] Further limitation, the Stern-Volmer equation is:

[0036]

[0037] In the formula, I p represents the phosphorescence intensity under the oxygen condition; I p0 is the phosphorescence intensity under the oxygen-free condition; K SV represents the sensitivity of the oxygen probe; and C represents the oxygen concentration of the environment in which the oxygen probe is located;

[0038] When there is oxygen, the phosphorescence signal intensity of the oxygen probe 8 received by the second detector 12 is I p , and the LED light source signal intensity received by the first detector 4 is I rThe ratio of the signal intensity of the two is recorded as optical parameter OP.

[0039]

[0040] The ratio of the signal intensity of the two is recorded as optical parameter OP0 under anaerobic condition.

[0041]

[0042] In the formula, I p0 is the phosphorescence signal intensity of the oxygen probe 8 received by the second detector 12 under anaerobic condition; I r0 is the signal intensity of the LED light source received by the first detector 4 under anaerobic condition;

[0043] It can be known from Formulas 2-4.

[0044]

[0045] Compared with the prior art, the present application has the following beneficial effects:

[0046] The present application sets multiple oxygen probes with different sensitivities, so that the device can work without manual intervention and replacement of the oxygen probe, and combines the light bleaching correction algorithm added in the measurement method, so that the phosphorescence intensity can be corrected in real time according to the measured oxygen concentration value and the known correction coefficient. In the case of using phosphorescence intensity as a relational parameter, the addition of light bleaching correction can reduce the oxygen measurement error, so that the measurement process can be adjusted adaptively according to the environmental oxygen concentration, the measurement of 0-100% oxygen range is realized, and the present application can be applied to environments with large changes in oxygen concentration, and the service life of the sensor can be also prolonged. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 The present application provides a schematic diagram of the adaptive phosphorescence oxygen concentration measurement device;

[0048] Figure 2 The present application provides a schematic diagram of the adaptive phosphorescence oxygen concentration measurement device;

[0049] Figure 3 The present application provides a schematic diagram of the adaptive phosphorescence oxygen concentration measurement device;

[0050] Figure 4 The present application provides a schematic diagram of the adaptive phosphorescence oxygen concentration measurement device;

[0051] Figure 5 The present application provides a schematic diagram of the adaptive phosphorescence oxygen concentration measurement device;

[0052] 1-LED lamp, 2-lens, 3-beam splitter, 4-first detector, 5-short wave pass filter, 6-light blocking seal plate, 7-transparent partition plate, 8-oxygen probe, 9-long wave pass filter, 11-transparent seal baffle, 12-second detector, 13-band pass filter, 14-inlet hole, 15-outlet hole. DETAILED DESCRIPTION

[0053] The technical solutions of the present application will be described clearly and completely below with reference to the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0054] In the description of the present application, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the orientations or positional relationships shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0055] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connection", "connecting" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0056] In addition, the technical features involved in the different embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0057] Example 1

[0058] Reference Figure 1 and 2 To specifically describe this embodiment, the adaptive phosphorescent oxygen concentration measurement method of this embodiment is realized based on the following device. The device instrument shell comprises upper and lower layers. The upper layer is an optical detection module, and the lower layer is a control / signal processing module, as shown in Figure 2 The specific optical detection module is a rectangular cuboid dark box divided into an upper cavity, a middle cavity and a lower cavity.

[0059] Five LEDs 1 are arranged at the top of the upper cavity, numbered from left to right as the first LED, second LED, third LED, fourth LED, and fifth LED. All five LEDs have the same power and emit light at a wavelength of 405nm. The five LEDs 1 are placed in parallel, and below each LED 1, a convex lens 2 and a beam splitter 3 are arranged in sequence. The distance between each LED 1 and the corresponding convex lens 2 is 30mm, and the angles of adjacent beam splitters 3 are different. From left to right, the angles between the beam splitter 3 and the vertical line are 55°, 60°, 65°, 75°, and 80°, respectively. This arrangement ensures that the light emitted by the LED 1 is converted into a parallel beam by the corresponding convex lens 2, and after passing through the corresponding beam splitter 3, a portion of the beam is reflected and received by the first detector 4. The upper cavity sidewall is provided with a first detector 4, which is a linear CCD detector. Five LEDs 1 are distributed in parallel along a straight line, and the straight line is perpendicular to the straight line where the first detector 4 is located. A short-pass filter 5 is provided in the window of the first detector 4, and the transmission wavelength of the short-pass filter 5 is greater than 450nm.

[0060] The upper cavity and the middle cavity are separated by a light-blocking sealing plate 6, and a transparent partition 7 is placed on the light-blocking sealing plate 6 at the position corresponding to the LED lamp 1. Oxygen probes 8 are placed in the middle cavity at the position corresponding to the LED lamp 1 in the upper cavity. Adjacent oxygen probes 8 have different placement angles and ranges. Specifically, from left to right, the oxygen probes 8 are numbered as oxygen probe A, oxygen probe B, oxygen probe C, oxygen probe D, and oxygen probe E. The ranges of oxygen probes A to E are 0–0.05 kPa, 0.05–1 kPa, 1–5 kPa, 5–20 kPa, and 20–100 kPa, respectively, with a sensitivity of 32.73 kPa. -1 6.535 kPa -1 1.023 kPa -1 0.347 kPa -1 and 0.076 kPa -1 The materials are PdOEP & Sol-gel, PdOEP & poly(St-TFEMA), PtOEP & EC, PtOEP & PS, and PtTPP & PMMA, respectively. The angles between oxygen probes A to E and the vertical line are 126°, 108°, 90°, 72°, and 54°, respectively. Each oxygen probe 8 has a long-pass filter 9 and a convex lens 2 below it. This arrangement ensures that the parallel phosphorescent beam emitted by the oxygen probe 8 converges into the window of the second detector 12 after passing through the corresponding convex lens 2. An air inlet 14 and an air outlet 15 are respectively opened on the two opposite sidewalls of the cavity. Both the air inlet 14 and the air outlet 15 are equipped with filters. Gas enters through the air inlet 14 and exits through the air outlet 15.

[0061] The middle cavity and the lower cavity are separated by a transparent sealing baffle 11, the material of the transparent sealing baffle 11 is high light transmission acrylic, the lower cavity is provided with a second detector 12, and a band-pass filter 13 with a transmission wavelength of 640-660 nm is arranged on the window of the second detector 12. In this way, the transparent sealing baffle 11 isolates the oxygen probe 8 and the convex lens 2 arranged below the oxygen probe 8 in the strip-shaped area, facilitating the rapid purging of the surface of the oxygen probe 8 by gas.

[0062] The control / signal processing module includes an electric signal processing module, a power module and a micro-processing unit. The power module includes a 3.5V constant voltage source controlled by five electrically controlled switches to supply power to the five LED lamps 1 respectively. The power module further includes a 5V direct current power source to supply power to the signal processing module and the microprocessor. The electric signal processing module is connected with the first detector and the second detector. The electric signal processing module is responsible for further processing of the current signal and appropriate amplification and filtering. The micro-processing unit is responsible for receiving and digitizing the electric signal and completing automatic measurement and algorithm operation by software. Specifically, the micro-processing unit controls the electrically controlled switches according to the set measurement program and processes the data obtained from the electric signal processing module to give the oxygen concentration measurement result.

[0063] The specific operation steps of the adaptive phosphorescence oxygen concentration measurement method of the embodiment are as follows:

[0064] S1, since the response range of the oxygen probe D is the largest, the oxygen probe D is first used to preliminarily measure the oxygen concentration. The micro-processing unit controls the electrically controlled switches to make the constant voltage source supply power to the fourth LED lamp. The light emitted by the fourth LED lamp is converted into parallel light beams by the corresponding convex lens 2 below the fourth LED lamp. The parallel light beams pass through the corresponding beam splitter 3, a part of which transmits to the oxygen probe D, and then passes through the convex lens 2 below the oxygen probe D, passes through the band-pass filter 13 with a transmission wavelength of 640-660 nm, and enters the window of the second detector 12. Another part is reflected to enter the window of the first detector 4 after passing through the short-wave pass filter 5. The fourth LED lamp works for 3s, and based on the Stern-Volmer equation, the oxygen concentration C0 is obtained.

[0065] The Stern-Volmer equation is:

[0066]

[0067] In the formula, I p represents the phosphorescence intensity under the presence of oxygen; I p0 is the phosphorescence intensity under the absence of oxygen; K SV represents the sensitivity of the oxygen probe; and C represents the oxygen concentration of the environment in which the oxygen probe is located.

[0068] In the presence of oxygen, the phosphorescence signal intensity emitted by the oxygen probe 8 received by the second detector 12 is I p , the LED light source signal intensity received by the first detector 4 is I r , and the ratio of the two signal intensities is denoted as the optical parameter OP.

[0069]

[0070] In the absence of oxygen, the ratio of the two signal intensities is denoted as the optical parameter OP0.

[0071]

[0072] In the formula, I p0 is the phosphorescence signal intensity emitted by the oxygen probe 8 received by the second detector 12 in the absence of oxygen; I r0 is the LED light source signal intensity received by the first detector 4 in the absence of oxygen.

[0073] As can be seen from Formulas 2-4,

[0074]

[0075] According to Formula 5, the oxygen concentration C is calculated as C0.

[0076] S2, according to the oxygen concentration C0obtained by S1, the microprocessor unit controls the electrically controlled switch to make the LED lamp 1 corresponding to the oxygen probe 8 with an applicable range of oxygen concentration C0work; and it is ensured that only one set of LED and oxygen probe works at the same time.

[0077] S3, when the oxygen probe 8 works, the phosphorescence intensity value I p0 in the Stern-Volmer equation is corrected in real time according to Formula 1.

[0078] I′ p0 = I p0 ·e (-t / K) (1)

[0079] In the formula, K is the light bleaching correction coefficient of the phosphorescence decay with time at different oxygen concentrations, and t represents the working time, which is provided by the timing function of the microprocessor.

[0080] S4, when the oxygen concentration exceeds 5% of the range of the working oxygen probe 8, the corresponding LED lamp 1 is immediately turned off, and the LED lamp 1 corresponding to the oxygen probe 8 with an applicable range is automatically selected to work according to the results before the turn-off, and the correction function is also updated.

[0081] S5, S3 and S4 are repeated to make the oxygen probe measure in self-adaptive adjustment.

[0082] Example 2:

[0083] Specifically, the oxygen probe D is taken as an example to illustrate the calibration and photobleaching correction method of the oxygen probe. Different concentrations of oxygen-containing gas are obtained by mixing nitrogen and oxygen, the optical parameters under different oxygen concentrations are measured, the calibration curve is determined according to formula (5), and the concentration calibration curve of the oxygen probe D is as shown in Figure 3 The two are linearly related. The phosphorescence decay with time under different oxygen concentrations is measured, the decay process is fitted using formula (5), and the slope of the curve is the photobleaching correction coefficient K. The relationship between the correction coefficient K and the oxygen concentration under different oxygen concentrations is as shown in Figure 4 The two are in accordance with the functional relationship as shown in formula (5).

[0084]

[0085] In the formula, a and b are influence factors, and for the oxygen probe D, the values of a and b are 6.71x10 -4 and 950.72, respectively.

[0086] When the oxygen probe D is working, the photobleaching correction coefficient K is updated in real time according to the measured value of the oxygen concentration, and is substituted into formula (4) to p0 Implement the correction.

[0087] Within the range of the oxygen probe D, the oxygen concentration in the gas chamber is detected by using the measuring device and the measuring method of example 1, the proportion of oxygen and nitrogen is adjusted to control the oxygen concentration in the gas chamber, and the measurement results of 0.6kPa, 0.9kPa, 1.2kPa, 1.5kPa, 1.8kPa and 2.1kPa oxygen concentration are as shown in Figure 5 The results show that the indication error measured by the method provided by the application is less than 2%.

[0088] Finally, it should be pointed out that: the above-described examples are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An adaptive phosphorescent oxygen concentration measuring device, characterized in that, The system includes an optical detection module and a control / signal processing module. The optical detection module is a cuboid dark box divided into an upper cavity, a middle cavity, and a lower cavity. Five LEDs are installed at the top of the upper cavity, and a convex lens and a beam splitter are installed below each LED in sequence. The beam splitters are placed at different angles. A first detector is installed on the side wall of the upper cavity, and a short-pass filter is installed in the window of the first detector. The upper cavity and the middle cavity are separated by a light-blocking sealing plate, and a transparent partition is installed on the light-blocking sealing plate at the position corresponding to the LEDs. Oxygen probes are installed in the middle cavity at the position corresponding to the LEDs in the upper cavity. The adjacent oxygen probes are placed at different angles and have different ranges. A long-pass filter and a convex lens are installed below each oxygen probe in sequence. An air inlet and an air outlet are opened on the two opposite side walls of the middle cavity, respectively. The middle cavity and the lower cavity are separated by a transparent sealing baffle. A second detector is installed at the bottom of the lower cavity, and a bandpass filter is installed in the window of the second detector. The control / signal processing module includes an electrical signal processing module, a power supply module, and a microprocessor unit. The power supply module is connected to and supplies power to the electrical signal processing module, the microprocessor unit, and the LED via an electronic control switch. The electrical signal processing module is connected to the first detector and the second detector. The microprocessor unit controls the electronic control switch according to the set measurement program and processes the data obtained from the electrical signal processing module to provide the oxygen concentration measurement result. The angles between the beam splitter and the vertical line in the upper cavity, starting from the end near the air inlet, are 55°, 60°, 65°, 75° and 80° respectively. The vent and the first detector are located on the same inner wall of the rectangular dark box; the five LEDs have the same power and the emission wavelength is 405nm. The angles between the oxygen probe and the vertical line in the middle cavity, starting from the end near the air inlet, are 126°, 108°, 90°, 72° and 54° respectively. The oxygen probe sensitivity within the cavity, starting from the end near the air inlet, is 32.73 kPa. -1 6.535 kPa -1 1.023 kPa -1 0.347 kPa -1 and 0.076 kPa -1 ; The distance between the LED light and the corresponding convex lens below it is 30mm; the vertical distance between the oxygen probe and the corresponding convex lens below it is 30mm. Short-pass filters transmit wavelengths less than 450 nm, long-pass filters transmit wavelengths greater than 500 nm, and band-pass filters transmit wavelengths of 640~660 nm. The power module includes a 3.5V constant voltage source, which is controlled by 5 electronic switches to power 5 LEDs.

2. An adaptive method for measuring phosphorescent oxygen concentration, characterized in that, Using the apparatus of claim 1, the method is as follows: S1, the microprocessor unit controls the electronic switch to supply power to the fourth LED, counting from the near-inlet end. The light emitted by the LED is converted into a parallel beam by the corresponding convex lens below it. This parallel beam passes through the corresponding beam splitter; part of it passes through and illuminates the fourth oxygen probe, then is converged by the convex lens below the fourth oxygen probe and enters the window of the second detector. The other part is reflected, passes through a short-pass filter, and enters the window of the first detector. After the LED continues to operate for 3 seconds, the oxygen concentration is obtained based on the Stern-Volmer equation. C 0; S2, the oxygen concentration derived from S1 C 0. The microprocessor unit controls the electronic switch to adjust the oxygen concentration. C The LED light corresponding to the oxygen probe (8) with a range of 0 is working; When the oxygen probe (8) is working, the phosphorescence intensity value in the Stern-Volmer equation is calculated using formula (1). I p0 Perform real-time correction; （1） In the formula, K The photobleaching correction coefficient is derived from the decay of phosphorescence over time under different oxygen concentrations. t The time taken to work is indicated by the timing function of the microprocessor; S4. When the oxygen concentration exceeds 5% of the working oxygen probe range, the corresponding LED light immediately turns off, and the LED light corresponding to the applicable oxygen probe range is automatically selected to work based on the result before turning off, and the calibration function is also updated accordingly. S5, repeat S3 and S4, to allow the oxygen probe to measure in adaptive adjustment.

3. The adaptive phosphorescent oxygen concentration measurement method according to claim 2, characterized in that, The Stern-Volmer equation is: （2） In the formula, I p Represents the phosphorescence intensity under aerobic conditions; I p0 The phosphorescence intensity under anaerobic conditions; K SV This represents the oxygen probe sensitivity; C This represents the oxygen concentration in the environment where the oxygen probe is located; When oxygen is present, the intensity of the phosphorescent signal emitted by the oxygen probe received by the second detector is: I p The LED light source signal strength received by the first detector is I r The ratio of their signal strengths is denoted as the optical parameter. OP ; （3） In the absence of oxygen, the ratio of the signal intensity of the two is denoted as an optical parameter. OP 0; （4） In the formula, I p0 The intensity of the phosphorescent signal emitted by the oxygen probe received by the second detector under anaerobic conditions; I r0 The intensity of the LED light source signal received by the first detector under oxygen-free conditions; From formulas (2) to (4), we can see that; （5）。

Images