A method and apparatus for implantable peritoneal oxygen concentration sensing and analysis

Abstract

The application discloses a method and device for implantable abdominal cavity oxygen concentration sensing detection and analysis, and belongs to the field of implantable abdominal cavity detection. The device comprises an external heat shrink tube, a parameter detection circuit, an oxygen detection light path, a coupling electrode and a battery. The oxygen detection light path comprises a reflective metal film, an oxygen sensitive film and an ethylene glycol phthalate sheet. The parameter detection circuit comprises a master control unit, a parameter measurement module, a magnetic control switch, a communication module and a power management unit. After the oxygen sensitive film contacts oxygen, internal phosphor molecules combine with oxygen molecules. Molecular oxygen interacts with light-emitting molecules, resulting in phosphorescence quenching, thereby reducing light intensity. The parameter detection circuit excites phosphorescence and performs photoelectric conversion to convert light intensity into an electrical signal, thereby realizing oxygen concentration detection. The application can quantify parameters in the abdominal cavity, and provides a platform for objectively evaluating changes in the physical environment in the abdominal cavity and long-term in-vivo low-power consumption detection.

Description

Technical Field

[0001] This invention relates to the field of implantable peritoneal detection, and in particular to a method and apparatus for implantable peritoneal oxygen concentration sensing and analysis. Background Technology

[0002] Implantable diagnostic devices hold significant potential for application in human health. In critical care medicine and major abdominal surgery, accurate and continuous monitoring of the intraperitoneal environment is crucial for determining clinical prognosis. Fatal complications such as abdominal compartment syndrome, occult intestinal ischemia, and abdominal infections often develop rapidly and insidiously. Traditional monitoring methods, such as intermittent intra-abdominal pressure measurement, body surface temperature, serum lactate, and imaging examinations, have inherent limitations, including time lag, data dispersion, and difficulty in reflecting the true state of deep tissues. This often leads to clinical decisions based on "passive response" rather than "active early warning," severely hindering the improvement of treatment success rates. In contrast, implantable microsensors, by placing miniature sensing units inside the body, can achieve continuous and accurate monitoring of key physiological parameters in the digestive tract. These devices are small in size and low in power consumption, and can be used with portable receivers or smartphones, greatly improving ease of use and patient compliance.

[0003] The main problems with existing implantable detection devices are as follows:

[0004] 1. Poor signal quality received

[0005] Traditional implantable detection devices mostly use Bluetooth transmission. The signal frequency band of around 2GHz has an absorption effect in human tissue, resulting in poor signal quality. At the same time, Bluetooth chips increase the size of the detection circuit, further increasing the overall system size.

[0006] 2. High power consumption of the device

[0007] To reduce the size of the device, it is generally powered by a small-capacity battery and communicates using Bluetooth or radio frequency systems. Traditional implantable devices consume power in the mA range, which makes it impossible for the device to perform long-term or full-process testing.

[0008] 3. Large sensor size

[0009] Implantable devices typically use electrochemical methods to collect oxygen concentration. This requires a large current consumption and necessitates the use of a gas chamber containing a solvent to construct the oxygen sensor, resulting in an increased overall size. Summary of the Invention

[0010] To address the shortcomings of existing technologies, the present invention aims to provide a method and apparatus for detecting and analyzing implantable peritoneal oxygen concentration.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: a device for implantable peritoneal oxygen concentration sensing and analysis, comprising: an external heat shrink tubing, a parameter detection circuit, an oxygen detection optical path, a coupling electrode, and a battery;

[0012] The oxygen detection optical path is set on the parameter detection circuit, which is connected to the coupling electrode and the battery. The entire device is wrapped in an external heat shrink tubing.

[0013] The oxygen detection optical path includes a reflective metal film, an oxygen-sensitive thin film, and a polyester substrate. The oxygen-sensitive thin film is disposed on the polyester substrate, and the reflective metal film covers the oxygen-sensitive thin film. When the oxygen-sensitive thin film comes into contact with oxygen, the phosphorescent molecules inside combine with the oxygen molecules. The interaction between the molecular oxygen and the luminescent molecules causes phosphorescence quenching, thereby reducing the light intensity. The oxygen detection optical path is excited by a parameter detection circuit and undergoes photoelectric conversion to convert the light intensity into an electrical signal, thereby realizing the detection of oxygen concentration.

[0014] Furthermore, the parameter detection circuit includes:

[0015] The main control unit is used to control the parameter detection circuit to start detection, set the carrier frequency communication signal frequency, and perform data calculation and analysis.

[0016] The parameter measurement module is used to detect oxygen concentration signals through analog or digital conversion.

[0017] A magnetic switch is used to stop the power supply to the device when it is not in use.

[0018] The communication module is used for encoding the on / off key control communication signals and measurement signals;

[0019] The power management unit provides a stable operating voltage for the communication module and the parameter measurement module.

[0020] Furthermore, the main control unit is a single-chip microcomputer minimum system, which is connected to the parameter measurement module through an analog or digital bus. It sets the detection frequency, reads the data sent by the parameter measurement module, processes and calibrates the data to obtain the voltage value corresponding to the oxygen concentration, and processes the voltage value and formula to obtain the oxygen concentration value. The main control unit is connected to the communication module and sends the 6M carrier frequency signal obtained by frequency doubling and the detection data to the communication module.

[0021] Furthermore, the communication module is a sn74aup1g57 minimum system, which uses an XOR logic to form an on / off keying code signal by combining the 6M carrier frequency signal and the detection data.

[0022] Furthermore, the parameter measurement module comprises a minimum system consisting of an operational amplifier, an excitation light source, a photodiode, and a filter, which performs phosphorescence excitation and voltage signal detection on the oxygen-sensitive film through the excitation light source, photodiode, and filter.

[0023] Furthermore, the oxygen detection optical path includes a support structure, the polyester substrate is a polyethylene terephthalate sheet, and the reflective metal film is a porous aluminum foil disposed at the bottom of the support structure.

[0024] Furthermore, the oxygen-sensitive film is prepared by the following method:

[0025] Prepare a mixture of acetone and 1,2-dichloroethane in a volume ratio of 1:3;

[0026] Add polymethyl methacrylate to the mixture and allow it to dissolve completely at room temperature;

[0027] Add platinum octaethylporphyrin, stir thoroughly, then add coumarin 545T and continue stirring;

[0028] The prepared solution was drop-coated onto a polyethylene terephthalate film and cured at room temperature to obtain an oxygen-sensitive film.

[0029] Furthermore, the coupling electrode is a set of copper foil conformal coupling antennas.

[0030] Furthermore, the device is embedded with a program for writing long-term system detection, specifically: the parameter detection circuit is in a low-power mode for a long time, wakes up once every 10 seconds to monitor the environment and update data for transmission.

[0031] The present invention also provides a method for detecting and analyzing implantable peritoneal oxygen concentration, comprising the following steps:

[0032] Prepare a mixture of acetone and 1,2-dichloroethane in a volume ratio of 1:3; add polymethyl methacrylate to the mixture and allow it to dissolve completely at room temperature; add platinum octaethylporphyrin, stir thoroughly, add coumarin 545T, and continue stirring; drop the prepared solution onto a polyethylene terephthalate sheet and cure at room temperature to obtain an oxygen-sensitive film;

[0033] An oxygen detection optical path is obtained by covering the oxygen-sensitive film and the ethylene glycol phthalate sheet with a reflective metal film.

[0034] The oxygen detection optical path is set on the parameter detection circuit, the parameter detection circuit is connected to the coupling electrode and the battery, and wrapped inside by an external heat shrink tubing to obtain the detection device.

[0035] The detection device is placed inside the abdominal cavity of the target. Oxygen in the abdominal cavity enters the oxygen detection optical path through an external heat shrink tubing. After receiving the oxygen signal, the light intensity of the oxygen-sensitive film changes. The light intensity signal is excited by the excitation light of the parameter detection circuit and the photodiode, and converted into a voltage signal to realize the detection of oxygen concentration.

[0036] The present invention has the following beneficial effects:

[0037] 1. In the field of oxygen concentration detection, this invention integrates an oxygen-sensitive thin film into a reflective optical path, achieving low-cost, small-volume oxygen detection. The size of the optical path and detection circuit is significantly reduced to 1 cm². 3 Inside.

[0038] 2. In terms of signal transmission, this invention designs a conformal coupled antenna to conduct signals through human tissue in the form of on / off keying, achieving a simpler signal transmission method while reducing the size required for communication devices.

[0039] 3. In terms of power consumption reduction, this invention utilizes a conformal coupled antenna combined with low-power software design to reduce the average power to the 50μA level, thereby improving the detection time of the device. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0041] Figure 1 This is an exploded view of the device of the present invention;

[0042] Figure 2 This is a structural diagram of the parameter detection circuit of the present invention;

[0043] Figure 3 This is an exploded view of the oxygen detection optical path of the present invention;

[0044] Figure 4 The flowchart for preparing the oxygen-sensitive membrane of this invention is as follows;

[0045] Figure 5 The following are characterization diagrams of the absorption and emission spectra of the oxygen sensing membrane, excitation source, and filter of the present invention.

[0046] Figure 6 This is a calibration curve of oxygen concentration versus light intensity response according to the present invention;

[0047] Figure 7 This is a schematic diagram of the on / off key control modulation principle of the present invention;

[0048] Figure 8 This is a diagram of the modulation signal transmitted by the coupled antenna of the present invention;

[0049] Figure 9 A flowchart of the low-power software programming for the device of the present invention;

[0050] Figure 10 This is a power consumption waveform diagram of the device of the present invention;

[0051] Figure 11 This is a schematic diagram showing the trend of oxygen concentration change detected by the gastrointestinal device of the present invention.

[0052] Figure 12 This is a schematic diagram illustrating the trend of intraperitoneal oxygen concentration changes in rats induced by low-concentration lipopolysaccharide according to the present invention.

[0053] Figure 13 This is a schematic diagram illustrating the trend of intraperitoneal oxygen concentration changes in rats induced by high-concentration lipopolysaccharide according to the present invention.

[0054] In the figure: 100, external heat shrink tubing; 200, parameter detection circuit; 300, oxygen detection optical path; 400, coupling electrode; 500, battery; 301, reflective metal film; 302, oxygen sensitive film; 303, polyester substrate. Detailed Implementation

[0055] The present invention will be further described below through specific embodiments.

[0056] In this invention, the use of terms such as "up," "down," "left," "right," "front," and "back" to indicate orientation or positional relationships is based on the orientation or positional relationships shown in the accompanying drawings. This is solely for the purpose of describing the invention and does not imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation on the scope of protection of this invention. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0057] Furthermore, in the description of this application, unless otherwise stated, "multiple" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0058] like Figure 1 As shown, this embodiment of the invention provides a device for implantable peritoneal oxygen concentration sensing and analysis, including: an external heat shrink tubing 100, a parameter detection circuit 200, an oxygen detection optical path 300, a coupling electrode 400, and a battery 500.

[0059] The oxygen detection optical path 300 is set on the parameter detection circuit 200. The parameter detection circuit 200 is connected to the coupling electrode 400 and the battery 500. The entire device is wrapped in an external heat shrink tubing 100.

[0060] Among them, such as Figure 3 As shown, the oxygen detection optical path 300 includes a reflective metal film 301, an oxygen-sensitive film 302, and a polyester substrate 303. The oxygen-sensitive film 302 is disposed on the polyester substrate 303, and the reflective metal film 301 covers the oxygen-sensitive film 302. When the oxygen-sensitive film 302 comes into contact with oxygen, the phosphorescent molecules inside combine with the oxygen molecules. The interaction between the molecular oxygen and the luminescent molecules causes phosphorescence quenching, thereby reducing the light intensity. The parameter detection circuit 200 excites the oxygen detection optical path 300 and performs photoelectric conversion, converting the light intensity into an electrical signal to realize the detection of oxygen concentration.

[0061] The external heat shrink tubing 100 is made of G•APEX MT2-0064 medical material; the coupling electrode 400 is a set of copper foil conformal coupling antennas.

[0062] As a preferred embodiment, such as Figure 2 As shown, the parameter detection circuit 200 includes:

[0063] The main control unit is used to control the parameter detection circuit 200 to start detection, set the carrier frequency communication signal frequency, and perform data calculation and analysis.

[0064] The parameter measurement module is used to detect oxygen concentration signals through analog or digital conversion.

[0065] A magnetic switch is used to stop the power supply to the device when it is not in use.

[0066] The communication module is used for encoding the on / off key control communication signals and measurement signals.

[0067] The power management unit provides a stable operating voltage for the communication module and the parameter measurement module.

[0068] The main control unit includes an MSP430 microcontroller and its minimum system; the parameter measurement module includes a minimum system consisting of a MAX9911 operational amplifier, an excitation light source XL0603BC440, and a photodiode NJL6401R; the measurement and control switch and communication module are sn74aup1g57 minimum systems; and the power management unit includes a linear regulator TPS63901 and its peripheral circuitry.

[0069] Preferably, the main control unit is connected to the parameter measurement module via an analog or digital bus, sets the detection frequency, reads the data sent by the parameter measurement module, processes and calibrates the data to obtain the voltage value corresponding to the oxygen concentration, and processes the voltage value and formula to obtain the oxygen concentration value. The main control unit is connected to the communication module, sending the 6M carrier frequency signal obtained by frequency doubling and the detection data to the communication module. The communication module forms an on / off keying code signal by using a XOR logic form between the 6M carrier frequency signal and the detection data. The oxygen-sensitive film 302 is phosphorescently excited and the voltage signal is detected by an excitation light source, a photodiode, and a filter.

[0070] In a preferred embodiment, the oxygen detection optical path 300 includes a support structure, and the reflective metal film 301 is a porous aluminum foil disposed at the bottom of the support structure.

[0071] Furthermore, such as Figure 4 As shown, the oxygen-sensitive film 302 is prepared as follows: First, a mixture of 2 mL acetone and 1,2-dichloroethane (volume ratio 1:3) is prepared. Then, 0.3 g of polymethyl methacrylate is added to the mixture, and it is stirred at room temperature in a magnetic stirrer until completely dissolved. Next, 6.05 mg of platinum octaethylporphyrin (PtOEP) is added, and the mixture is stirred for 30 minutes. Afterward, 10.54 mg of coumarin 545T (c545T) is added, and the solution is stirred for another 30 minutes. The prepared solution is then drop-coated onto a polyethylene terephthalate sheet, covering the porous aluminum foil.

[0072] As a preferred embodiment, the absorption and emission spectra of the prepared oxygen-sensitive thin film 302, excitation light source, and filter are as follows: Figure 5 As shown, the absorption peak of the oxygen-sensitive film 302 is near the emission peak of the excitation source, and the emission spectrum of the oxygen-sensitive film 302 under the action of excitation light is near the absorption peak of the filter.

[0073] The calibration curve of the light intensity of the oxygen-sensitive film 302 as a function of the oxygen concentration in the environment is shown below. Figure 6 As shown.

[0074] In a preferred embodiment, the device implements on / off keying modulation at a frequency of 6 MHz. This special on / off keying signal is achieved by the main control module in conjunction with the communication module by inverting the carrier phase; the in-phase state represents 0, and the out-of-phase state represents 1. This differential signal can increase the transmission amplitude to twice the power supply voltage, thereby increasing the energy coupled to the human body. Figure 7 As shown, the signal is modulated together with the 6MHz carrier signal using an XOR gate to achieve data transmission at the transmitting end. The actual modulation signal diagram of the coupled antenna is shown in the figure below. Figure 8 As shown.

[0075] In a preferred embodiment, the device incorporates a method for implementing long-term system detection using software programming, such as... Figure 9 As shown, a software framework for front-end and back-end logic is selected, and the MSP430 system is set to low-power mode 3. The parameter detection circuit 200 is woken up every 10 seconds to monitor the environment and update the data before sending it.

[0076] Actual power consumption of the device is as follows Figure 10 As shown, the current in the resting state is 40μA, data acquisition and calculation can be completed within 2 milliseconds, and the average current is 2mA.

[0077] This invention also provides a method for detecting and analyzing implantable peritoneal oxygen concentration, comprising the following steps:

[0078] Prepare a mixture of acetone and 1,2-dichloroethane in a volume ratio of 1:3; add polymethyl methacrylate to the mixture and allow it to dissolve completely at room temperature; add platinum octaethylporphyrin, stir thoroughly, add coumarin 545T, and continue stirring; drop the prepared solution onto a polyethylene terephthalate sheet and cure at room temperature to obtain an oxygen-sensitive film 302.

[0079] The oxygen-sensitive film 302 is disposed on a polyethylene terephthalate sheet and covered with a reflective metal film 301 to obtain an oxygen detection optical path 300.

[0080] The oxygen detection optical path 300 is set on the parameter detection circuit 200, the parameter detection circuit 200 is connected to the coupling electrode 400 and the battery 500, and wrapped inside by the external heat shrink tubing 100 to obtain the detection device.

[0081] The detection device is placed inside the abdominal cavity of the target. Oxygen in the abdominal cavity enters the oxygen detection optical path 300 in the device through the external heat shrink tubing 100. After receiving the oxygen signal, the oxygen sensitive film 302 changes the light intensity. The light intensity signal is excited and converted into a voltage signal by the excitation light and photodiode in the parameter detection circuit 200, thereby realizing the detection of oxygen concentration.

[0082] As a preferred embodiment, the following experiment was conducted based on the device of the present invention, and the experiment specifically included:

[0083] New Zealand rabbits were used as in vivo evaluation animals for the device. The device was inserted orally into the gastrointestinal tract of the rabbits. The oxygen concentration signal detected by the device was as follows: Figure 11As shown, oxygen levels did not decrease significantly in the upper digestive tract. Around 3:00 PM, the oxygen concentration began to decrease slowly and steadily. In the small intestine, this decrease was almost uniform until it fell below 5%. Microbial fermentation gradually consumed the oxygen in the intestinal contents, and as the intestines extended, the oxygen content gradually decreased, reaching a near-anaerobic environment in the colon and rectum.

[0084] Intraperitoneal injection of LPS (lipopolysaccharide) is a standardized method for inducing inflammation in experimental studies, mainly used to establish acute or chronic inflammation models in rodents (such as rats).

[0085] like Figure 13 The figure shows the results of peritoneal environment detection after induction with 0.6 mg low-concentration LPS. The device was implanted into the peritoneal cavity of rats, and 0.6 mg of low-concentration LPS was injected into the peritoneal cavity. The data in the peritoneal cavity of the rats were observed. As can be seen from the figure, the oxygen concentration decreased, and this state began to recover after about 6 hours, with the oxygen concentration gradually increasing.

[0086] like Figure 12 The image shows the results of peritoneal environment detection after induction with 3mg high-concentration LPS. The device was implanted into the peritoneal cavity of rats, and 3mg of high-concentration LPS was injected into the peritoneal cavity. The data in the peritoneal cavity of the rats were observed. The results showed that the oxygen concentration of the rats decreased continuously after injection, down to about 5%.

[0087] The method and device for implantable peritoneal oxygen concentration sensing and analysis of the present invention can realize low-power miniaturized detection of in vivo oxygen concentration in the digestive tract, quantify various physiological reactions in the peritoneal cavity, and provide a powerful platform for objectively assessing changes in the physical environment of the peritoneal cavity. It can be applied to various application scenarios such as clinical prognosis monitoring, research on the dynamic evolution of peritoneal pathophysiology in critical illness, and postoperative monitoring after organ transplantation, realizing a shift from "passive response" to "active early warning".

[0088] The above are merely specific embodiments of the present invention, but the design concept of the present invention is not limited thereto. Any non-substantial modifications made to the present invention using this concept shall be considered as infringing upon the protection scope of the present invention.

Claims

1. A device for implantable peritoneal oxygen concentration sensing and analysis, characterized in that, include: External heat shrink tubing (100), parameter detection circuit (200), oxygen detection optical path (300), coupling electrode (400), and battery (500); The parameter detection circuit (200) includes: a main control unit, used to control the parameter detection circuit (200) to start detection, set the carrier frequency communication signal frequency, and perform data calculation and analysis; a parameter measurement module, used to detect oxygen concentration signals through analog or digital conversion; a magnetic switch, used to stop power supply when the device is not in use; a communication module, used to encode the on / off key control communication signal and the measurement signal; and a power management unit, used to provide a stable operating voltage for the communication module and the parameter measurement module. The communication module is a minimum XOR gate system, which uses an XOR logic form to form an on / off key control encoded signal by combining the 6MHz carrier frequency signal and the detection data. The oxygen detection optical path (300) is set on the parameter detection circuit (200), the parameter detection circuit (200) is connected to the coupling electrode (400) and the battery (500), and the entire device is wrapped in an external heat shrink tubing (100); The oxygen detection optical path (300) includes a reflective metal film (301), an oxygen-sensitive film (302), and a polyester substrate (303). The oxygen-sensitive film (302) is disposed on the polyester substrate (303), and the reflective metal film (301) covers the oxygen-sensitive film (302). When the oxygen-sensitive film (302) comes into contact with oxygen, the phosphorescent molecules inside combine with the oxygen molecules. The interaction between the molecular oxygen and the luminescent molecules causes phosphorescence quenching, thereby reducing the light intensity. The oxygen detection optical path (300) is excited by the light source and photoelectric conversion is performed by the parameter detection circuit (200) to convert the light intensity into an electrical signal to realize the detection of oxygen concentration. The oxygen detection optical path (300) includes a support structure, the polyester substrate (303) is a polyethylene phthalate sheet, the reflective metal film (301) is a porous aluminum foil as the reflective optical path substrate, and is disposed at the bottom of the support structure; the coupling electrode (400) is a set of copper foil conformal coupling antennas.

2. The apparatus according to claim 1, characterized in that, The main control unit is a single-chip microcomputer minimum system, which is connected to the parameter measurement module via an analog or digital bus. It sets the detection frequency, reads the data sent by the parameter measurement module, processes and calibrates the data to obtain the voltage value corresponding to the oxygen concentration, and processes the voltage value and formula to obtain the oxygen concentration value. The main control unit is connected to the communication module and sends the 6MHz carrier frequency signal obtained by frequency doubling and the detection data to the communication module.

3. The apparatus according to claim 1, characterized in that, The parameter measurement module comprises a minimum system consisting of an operational amplifier, an excitation light source, a photodiode, and a filter. It performs phosphorescence excitation and voltage signal detection on the oxygen-sensitive film (302) through the excitation light source, the photodiode, and the filter.

4. The apparatus according to claim 1, characterized in that, The oxygen-sensitive thin film (302) is prepared by the following method: Prepare a mixture of acetone and 1,2-dichloroethane in a volume ratio of 1:3; Add polymethyl methacrylate to the mixture and allow it to dissolve completely at room temperature; Add platinum octaethylporphyrin, stir thoroughly, then add coumarin 545T and continue stirring; The prepared solution was drop-coated onto a polyethylene phthalate sheet and cured at room temperature to obtain an oxygen-sensitive film.

5. The apparatus according to claim 1, characterized in that, The device has an embedded program for long-term detection, specifically: the parameter detection circuit is in a low-power mode for a long time, wakes up every 10 seconds to monitor the environment and update data before sending it.

6. A method for detecting and analyzing oxygen concentration in an implantable peritoneal cavity, implemented based on the device described in any one of claims 1-5, characterized in that, Includes the following steps: Prepare a mixture of acetone and 1,2-dichloroethane in a volume ratio of 1:3; add polymethyl methacrylate to the mixture and allow it to dissolve completely at room temperature; add platinum octaethylporphyrin, stir thoroughly, add coumarin 545T, and continue stirring; drop the prepared solution onto a polyethylene phthalate sheet and cure at room temperature to obtain an oxygen-sensitive film (302). The oxygen-sensitive film (302) and the polyethylene terephthalate sheet are covered with a reflective metal film (301) to obtain an oxygen detection optical path (300). The oxygen detection optical path (300) is set on the parameter detection circuit (200), the parameter detection circuit (200) is connected to the coupling electrode (400) and the battery (500), and wrapped inside by an external heat shrink tubing (100) to obtain a detection device; When the detection device is placed inside the abdominal cavity of the target, the oxygen in the abdominal cavity enters the oxygen detection optical path (300) through the external heat shrink tubing (100). After receiving the oxygen signal, the oxygen sensitive film (302) changes the light intensity. The light intensity signal is excited and converted into a voltage signal by the parameter detection circuit (200) to realize the detection of oxygen concentration.

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