A calibration module and calibration method for tracing blood oxygen saturation values ​​of a blood oxygen saturation simulator calibration device

Abstract

The present invention relates to a calibration module and a calibration method for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device. The calibration module of the present invention is a simulated finger, and its shape simulates the shape of a human finger. A hole is dug in the center of the simulated finger, and a neutral filter is embedded in the hole. The neutral filter includes neutral filters with transmittances of 95%, 90%, 85%, 80%, 75%, and 70%; and also includes neutral filters with increased transmittances of 55%, 45%, and 30%. The main technical indicators when using the calibration module to trace the blood oxygen saturation value of the blood oxygen saturation simulator calibration device are the blood oxygen saturation value measurement range: 28.6%, 44.3%, 55.4%, 68.3%, 72.8%, 78.7%, 83.5%, 90.4%, 93.8%, 100%, and the maximum allowable error of the blood oxygen saturation value measurement result: ±0.5%. The invention has a simple structure, and the calibration result is accurate, efficient and easy to operate.

Description

Technical Field

[0001] The present invention relates to a blood oxygen saturation simulator calibration device in the field of medical instruments, and in particular to a calibration module and a calibration method for tracing the blood oxygen saturation value of the blood oxygen saturation simulator calibration device. Background Art

[0002] The blood oxygen saturation simulator calibration device is a quality control device used to calibrate the photoelectric blood oxygen saturation simulator. Figure 1 As shown, the calibration device of the blood oxygen saturation simulator mainly consists of three parts: the calibration device host 1, the standard finger clip 2 and the computer 3 containing the calibration software. The calibration device host 1 drives the LED light source of the standard finger clip 2 to emit red light and infrared light of fixed intensity through photoelectric conversion with a fixed voltage signal, and receives the attenuated light signal emitted by the blood oxygen saturation simulator 4 equipped with the optical simulation finger 5 through the photoelectric detector of the standard finger clip 2. After receiving the attenuated electrical signal transmitted by the standard finger clip 2 through photoelectric conversion, the calibration device host 1 provides the calculated data to the calibration software, and the calibration software performs data analysis, processing and report generation after obtaining the data.

[0003] Previously, the blood oxygen saturation value of the blood oxygen saturation simulator calibration device was calibrated using neutral filters with different transmittances. Neutral filters with different transmittances were placed between the LED light source and the photodetector of the standard finger clip 2 in turn, and the percentage of the voltage generated by the photodetector after receiving the attenuated light signal relative to the reference voltage was detected, and compared with the standard value of the neutral filter transmittance to calibrate the blood oxygen saturation value. In addition to the transmittance of the neutral filter, the intensity of the attenuated light signal received by the photodetector will also be affected by factors such as the light incident angle and the ambient light brightness. Placing the neutral filter directly between the LED light source and the photodetector of the standard finger clip 2 will produce a large gap, resulting in a large amount of ambient light being received by the photodetector, causing experimental errors; in addition, the angle between the neutral filter and the light cannot be fixed, resulting in differences in the light incident angle for each measurement, increasing the experimental error. If the light incident angle for each measurement is to be as similar as possible, a lot of time is required to adjust the angle and position of the neutral filter in the standard finger clip 2. The transmittance of neutral filters is basically fixed at 10%, 25%, 30%, 40%, and 50%. If you want to obtain light signals with other attenuation rates, you need to combine the existing neutral filters. Since the gaps between the neutral filters after combination cannot be eliminated, the transmittance of the combined neutral filters cannot be accurately determined, resulting in an increase in the error of the transmittance of the neutral filters themselves. In addition, some light attenuation rates cannot be obtained by combining neutral filters with fixed transmittance ratios, so it is necessary to customize neutral filters with corresponding transmittance ratios.

[0004] When using a fixed transmittance neutral filter to trace the blood oxygen saturation value of the blood oxygen saturation simulator calibration device, due to the large measurement error (see Table 1), the measurement result cannot be used directly to determine whether the blood oxygen saturation value of the blood oxygen saturation simulator calibration device meets the measurement requirements. The result must be determined by calculating the linear relationship between the percentage of the photodetector voltage relative to the reference voltage and the neutral filter transmittance, that is, as long as the measurement result of the photodetector voltage relative to the reference voltage percentage is proportional to the neutral filter transmittance, it can be determined that the blood oxygen saturation value of the blood oxygen saturation simulator calibration device meets the measurement requirements. However, the method of using a linear relationship for determination is more cumbersome, and the calibration value of the blood oxygen saturation value of the blood oxygen saturation simulator calibration device cannot be accurately obtained.

[0005] Table 1. Calibration results of blood oxygen saturation values ​​of blood oxygen saturation simulator calibration device using fixed transmittance neutral filter

[0006]

[0007] In view of the defects of the above-mentioned existing blood oxygen saturation simulator calibration device blood oxygen saturation value calibration tool and calibration method, the inventor has finally created the present invention which is of real practical value after continuous research and design, repeated trial production and improvement. Summary of the invention

[0008] The purpose of the present invention is to overcome the defects of the existing calibration tools for tracing the blood oxygen saturation values ​​of the blood oxygen saturation simulator calibration device, and to provide a calibration module with a new structure for tracing the blood oxygen saturation values ​​of the blood oxygen saturation simulator calibration device, so that it is an accurate, efficient and easy-to-operate tracing tool, and thus more suitable for practical use.

[0009] Another object of the present invention is to overcome the defects of the existing calibration method for tracing the blood oxygen saturation value of the blood oxygen saturation simulator calibration device, and to provide a new calibration method for tracing the blood oxygen saturation value of the blood oxygen saturation simulator calibration device. The technical problem to be solved is to make it an accurate, efficient and easy-to-operate tracing method, so that it is more suitable for practical use.

[0010] The purpose of the present invention and the technical problem to be solved are achieved by adopting the following technical solutions. According to the present invention, a calibration module for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device includes a simulated finger and a neutral filter. The shape of the simulated finger simulates the shape of a human finger. A hole is dug in the center of the simulated finger. The neutral filter is embedded in the hole to fix the neutral filter in an embedded manner. The simulated finger is tightly matched with the inner structure of the standard finger clip and the material used is opaque to reduce the detection of unnecessary ambient light by the photoelectric detector.

[0011] The purpose of the present invention and the solution to its technical problems can be further achieved by adopting the following technical measures.

[0012] The aforementioned calibration module for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device, wherein the neutral filters include: the most commonly used neutral filters with transmittance, namely, a neutral filter with a transmittance of 95%, a neutral filter with a transmittance of 90%, a neutral filter with a transmittance of 85%, a neutral filter with a transmittance of 80%, a neutral filter with a transmittance of 75% and a neutral filter with a transmittance of 70%;

[0013] The neutral filter also includes neutral filters with increased transmittance, namely, a neutral filter with a transmittance of 55%, a neutral filter with a transmittance of 45%, and a neutral filter with a transmittance of 30%;

[0014] 100% transmittance was achieved with a simulated finger without an embedded neutral density filter.

[0015] The aforementioned calibration module for tracing the blood oxygen saturation value of the blood oxygen saturation simulator calibration device, wherein the area of ​​the central hole of the simulated finger is 95mm 2 -100mm 2 , to ensure that the light emitted by the LED light source of the standard finger clamp can all pass through the neutral filter, to ensure that the light emitted by the LED light source of the standard finger clamp can pass through the neutral filter and be detected by the photoelectric detector set in the standard finger clamp during each calibration, and the light can be vertically incident on the neutral filter during each calibration.

[0016] The aforementioned calibration module for tracing the blood oxygen saturation value of the blood oxygen saturation simulator calibration device, after the simulated finger is fully inserted into the standard finger clamp, the LED light source, the neutral filter and the photodetector are opposite to each other, and the light passes vertically through the neutral filter.

[0017] The purpose of the present invention and the technical problem solved by the present invention are also achieved by adopting the following technical solutions. According to the present invention, a calibration method for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device is proposed, which comprises the following steps:

[0018] Step 1: Before calibration, ensure that all components in the blood oxygen saturation simulator calibration device are correctly connected, that is, the computer containing the calibration software is connected to the calibration device host, the calibration device host is connected to the standard finger clip, and the light source around the blood oxygen saturation simulator calibration device is turned off to make the ambient light brightness as low as possible;

[0019] Step 2: Start each component of the blood oxygen saturation simulator calibration device, open the calibration software and enter the self-calibration mode, and fix the reference voltage;

[0020] Step 3: Fully insert the simulated finger with 100% transmittance into the standard finger clip;

[0021] Step 4: Read and record the percentage of the voltage feedback from the photodetector relative to the reference voltage shown in the calibration software;

[0022] Step 5: Re-insert the simulated finger into the standard finger clip completely, read and record the percentage of the voltage feedback from the photodetector relative to the reference voltage, a total of 3 times;

[0023] Step 6: Take the average of the three measurement results as the calibration value, and compare it with the standard value, i.e. the transmittance indicated on the calibrator, to calculate the indication error. The difference between the calibration value and the standard value is the indication error.

[0024] Step 7: According to steps 1-6, use in turn a simulated finger embedded with a neutral filter with a transmittance of 95%, a simulated finger embedded with a neutral filter with a transmittance of 90%, a simulated finger embedded with a neutral filter with a transmittance of 85%, a simulated finger embedded with a neutral filter with a transmittance of 80%, a simulated finger embedded with a neutral filter with a transmittance of 75%, a simulated finger embedded with a neutral filter with a transmittance of 70%; a simulated finger embedded with a neutral filter with a transmittance of 55%, a simulated finger embedded with a neutral filter with a transmittance of 45%, and a simulated finger embedded with a neutral filter with a transmittance of 30% to calibrate the blood oxygen saturation value of the blood oxygen saturation simulator calibration device.

[0025] Compared with the prior art, the present invention has obvious advantages and beneficial effects. It has at least the following advantages:

[0026] 1. The present invention has a simple structure and relatively reduced manufacturing cost, which can significantly reduce costs and improve economic benefits. In terms of practicality and cost-effectiveness, it fully meets the needs of industrial development and has considerable industrial utilization value.

[0027] 2. When the present invention is used to trace the blood oxygen saturation value of the blood oxygen saturation simulator calibration device, the measurement error of the photodetector voltage relative to the reference voltage percentage is greatly reduced. The calibration result can be directly used to determine whether the blood oxygen saturation value meets the requirements, and the calibration value and indication error can be accurately obtained, as shown in Table 2.

[0028] Table 2. Calibration results of blood oxygen saturation values ​​of the blood oxygen saturation simulator calibration device using the calibration module

[0029]

[0030] Based on the calibration results of the blood oxygen saturation values ​​of the blood oxygen saturation simulator calibration device in Table 2, the main technical indicators when using the calibration module to trace the blood oxygen saturation values ​​of the calibration device are obtained: blood oxygen saturation value measurement range: 28.6%, 44.3%, 55.4%, 68.3%, 72.8%, 78.7%, 83.5%, 90.4%, 93.8%, 100%; the maximum allowable error of the blood oxygen saturation value measurement result: ±0.5%.

[0031] 3. The existing calibration method is to directly use a neutral filter for calibration, which has defects such as light leakage, unstable light incident angle, extremely large gaps, and transmittance that cannot meet calibration requirements. This makes the calibration process cumbersome; adjusting the incident angle makes the calibration time too long; the calibration error is too large to be directly used to determine the calibration result, and a linear relationship needs to be calculated for determination.

[0032] The present invention eliminates or greatly reduces the above defects to a certain extent. The material is opaque, and the simulated finger can fit perfectly with the internal structure of the standard finger clip, basically eliminating the defects of light leakage and large gaps; the shape of the simulated finger is fixed, and the area of ​​the center hole embedded in the neutral filter is large enough to ensure that the light emitted by the LED light source of the standard finger clip can be detected by the photoelectric detector of the standard finger clip through the neutral filter during each calibration, and the light can be vertically incident on the neutral filter during each calibration; the neutral filter used in the present invention is customized, and the transmittance is traced through the calibration of the national metrology standard spectral photometric filter standard device to meet the calibration requirements; the measurement accuracy of the present invention is high, and the calibration results can be directly used to determine whether the calibrated equipment meets the standard, eliminating the step of calculating the linear relationship and reducing the corresponding error. In summary, the present invention does not leak light, has a small gap, the incident angle is vertical and does not need to be adjusted, and the transmittance can meet the calibration requirements; the calibration process is simplified, the calibration time is greatly reduced, and the experimental error is greatly reduced.

[0033] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the following specifically cites a preferred embodiment and describes it in detail with the accompanying drawings as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a structural diagram of the blood oxygen saturation simulator calibration device.

[0035] Figure 2 It is a structural schematic diagram of the present invention.

[0036] Figure 3 It is a schematic diagram of the present invention and a standard finger clamp.

[0037] in:

[0038] 1: Calibration device host 2: Standard finger clamp

[0039] 3: Computer with calibration software 4: Blood oxygen saturation simulator

[0040] 5: Optical simulated finger 6: Simulated finger

[0041] 7: Neutral filter DETAILED DESCRIPTION

[0042] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the following is a calibration module and a calibration method for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device according to the present invention in combination with the accompanying drawings and preferred embodiments.

[0043] See also Figure 2 As shown, a calibration module for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device in a preferred embodiment of the present invention includes a simulated finger 6 and a neutral filter 7. The simulated finger 6 simulates the shape of a human finger, and a hole is dug in the center of the simulated finger 6. The area of ​​the center hole of the simulated finger 6 is large enough to ensure that the light emitted by the LED light source of the standard finger clip can all pass through the neutral filter 7. The area of ​​the center hole of the simulated finger 6 is 95mm 2 -100mm 2 , to ensure that the light emitted by the LED light source of the standard finger clip 2 can all pass through the neutral filter 7, to ensure that the light emitted by the LED light source of the standard finger clip 2 can pass through the neutral filter 7 and be detected by the photoelectric detector set in the standard finger clip 2 during each calibration, and the light can be vertically incident on the neutral filter 7 during each calibration.

[0044] The neutral density filter 7 is embedded in the hole of the simulated finger 6 and fixed in an embedded manner. The simulated finger is closely matched with the inner structure of the standard finger clip 2 and the material used is opaque to reduce the detection of unnecessary ambient light by the photodetector. After the simulated finger 6 is fully inserted into the standard finger clip 2, the LED light source, the neutral density filter 7 and the photodetector are opposite to each other, and the light passes through the neutral density filter vertically.

[0045] The calibration device is a standard instrument of JJF 1542-2015 "Blood oxygen saturation simulator calibration specification". The most commonly used blood oxygen saturation value calibration points are 100%, 95%, 90%, 85%, 80%, 75%, and 70%. The attenuation rate of the attenuated light signal received by the photodetector corresponds to it. Therefore, a neutral filter 7 with a corresponding transmittance is customized for the traceability of the blood oxygen saturation value of the most commonly used calibration point. On this basis, three uncommon calibration points of 55%, 45%, and 30% are added. The 100% transmittance is realized by a hollow simulated finger 6, and the remaining 9 calibration modules are composed of the same simulated finger 6 and a neutral filter 7 with a corresponding transmittance. The transmittance corresponding to the calibration module will be marked on the simulated finger.

[0046] The measured transmittance of the neutral density filters of all calibration modules is traceable after calibration with the national metrology standard spectral photometric filter standard device, see Table 3.

[0047] Table 3. Calibration module transmittance

[0048]

[0049] The neutral filter 7 includes: the most commonly used neutral filter 7 with transmittance, namely, a neutral filter 7 with a transmittance of 95%, a neutral filter 7 with a transmittance of 90%, a neutral filter 7 with a transmittance of 85%, a neutral filter 7 with a transmittance of 80%, a neutral filter 7 with a transmittance of 75% and a neutral filter 7 with a transmittance of 70%;

[0050] The neutral filter 7 also includes neutral filters with increased transmittance, namely, a neutral filter 7 with a transmittance of 55%, a neutral filter 7 with a transmittance of 45% and a neutral filter 7 with a transmittance of 30%; a 100% transmission ratio is achieved by a simulated finger 6 without an embedded neutral filter 7.

[0051] A calibration method for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device according to a preferred embodiment of the present invention mainly comprises the following steps:

[0052] Step 1: Before calibration, ensure that all components in the blood oxygen saturation simulator calibration device are correctly connected, that is, the computer 2 containing the calibration software is connected to the calibration device host 1, the calibration device host 1 is connected to the standard finger clip 2, and the light source around the blood oxygen saturation simulator calibration device is turned off to make the ambient light brightness as low as possible;

[0053] Step 2: Start each component of the blood oxygen saturation simulator calibration device, open the calibration software and enter the self-calibration mode, and fix the reference voltage;

[0054] Step 3: Fully insert the simulated finger 6 with 100% transmittance into the standard finger clip 2;

[0055] Step 4: Read and record the percentage of the voltage feedback from the photodetector relative to the reference voltage shown in the calibration software;

[0056] Step 5: Re-insert the simulated finger 6 into the standard finger clip 2 completely, and read and record the percentage of the voltage feedback from the photodetector relative to the reference voltage for a total of 3 times;

[0057] Step 6: Take the average of the three measurement results as the calibration value, and compare it with the standard value, i.e. the transmittance indicated on the calibrator, to calculate the indication error. The difference between the calibration value and the standard value is the indication error.

[0058] Step 7: According to steps 1-6, use in turn the simulated finger 6 embedded with a neutral filter with a transmittance of 95%, the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 90%, the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 85%, the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 80%, the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 75%, the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 70%; the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 55%, the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 45%, and the simulated finger 6 embedded with a neutral filter 7 with a transmittance of 30% to calibrate the blood oxygen saturation value of the blood oxygen saturation simulator calibration device.

[0059] When the present invention is used to trace the blood oxygen saturation value of the blood oxygen saturation simulator calibration device, the measurement error of the percentage of the photodetector voltage relative to the reference voltage is greatly reduced, and the calibration result can be directly used to determine whether the blood oxygen saturation value meets the requirements, and the calibration value and the indication error can be accurately obtained, as shown in Table 3. Based on the blood oxygen saturation value calibration results of the blood oxygen saturation simulator calibration device in Table 3, the main technical indicators when the calibration module is used to trace the blood oxygen saturation value of the calibration device are obtained: blood oxygen saturation value measurement range: 28.6%, 44.3%, 55.4%, 68.3%, 72.8%, 78.7%, 83.5%, 90.4%, 93.8%, 100%, and the maximum allowable error of the blood oxygen saturation value measurement result: ±0.5%.

[0060] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A calibration module for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device, characterized in that: The device comprises a simulated finger (6) and a neutral density filter (7), wherein the simulated finger (6) is shaped like a human finger, a hole is dug at the center of the simulated finger (6), the neutral density filter (7) is embedded in the hole, and the neutral density filter (7) is fixed in an embedded manner, the simulated finger (6) is closely matched with the inner structure of the standard finger clip (2), and the material used is opaque, so as to reduce the detection of unnecessary ambient light by the photoelectric detector; The neutral filters (7) include: the most commonly used neutral filters with transmittance ratios, namely, a neutral filter (7) with a transmittance ratio of 95%, a neutral filter (7) with a transmittance ratio of 90%, a neutral filter (7) with a transmittance ratio of 85%, a neutral filter (7) with a transmittance ratio of 80%, a neutral filter (7) with a transmittance ratio of 75%, and a neutral filter (7) with a transmittance ratio of 70%. The neutral filter (7) further comprises a neutral filter (7) with increased transmittance, namely a neutral filter (7) with a transmittance of 55%, a neutral filter (7) with a transmittance of 45%, and a neutral filter (7) with a transmittance of 30%. 100% transmittance is achieved by using a simulated finger (6) without an embedded neutral density filter (7); The area of ​​the center hole of the simulated finger (6) is 95 mm 2 -100mm 2 , to ensure that the light emitted by the LED light source of the standard finger clip (2) can all pass through the neutral filter (7), to ensure that the light emitted by the LED light source of the standard finger clip (2) can pass through the neutral filter (7) and be detected by the photoelectric detector arranged in the standard finger clip (2) during each calibration, and that the light can vertically enter the neutral filter (7) during each calibration.

2. A calibration module for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device according to claim 1, characterized in that After the simulated finger (6) is completely inserted into the standard finger clamp (2), the LED light source, the neutral filter (7) and the photoelectric detector are opposite to each other, and the light passes vertically through the neutral filter (7).

3. A calibration method for a calibration module for tracing the blood oxygen saturation value of a blood oxygen saturation simulator calibration device according to claim 1 or 2, characterized in that: It includes the following steps: Step 1: Before calibration begins, ensure that all components in the blood oxygen saturation simulator calibration device are properly connected, that is, the computer containing the calibration software is connected to the calibration device host (1), the calibration device host (1) is connected to the standard finger clip (2), and the light source around the blood oxygen saturation simulator calibration device is turned off to make the ambient light brightness as low as possible; Step 2: Start each component of the blood oxygen saturation simulator calibration device, open the calibration software and enter the self-calibration mode, and fix the reference voltage; Step 3: Fully insert the simulated finger (6) with 100% transmittance into the standard finger holder (2); Step 4: Read and record the percentage of the voltage feedback from the photodetector relative to the reference voltage shown in the calibration software; Step 5: Re-insert the simulated finger (6) completely into the standard finger clip (2), read and record the percentage of the voltage feedback from the photodetector relative to the reference voltage, a total of 3 times; Step 6: Take the average of the three measurement results as the calibration value, and compare it with the standard value, i.e. the transmittance indicated on the calibrator, to calculate the indication error. The difference between the calibration value and the standard value is the indication error. Step 7: According to steps 1-6, the blood oxygen saturation value of the blood oxygen saturation simulator calibration device is calibrated using a simulated finger (6) embedded with a neutral filter with a transmittance of 95%, a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 90%, a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 85%, a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 80%, a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 75%, and a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 70% in sequence; a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 55%, a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 45%, and a simulated finger (6) embedded with a neutral filter (7) with a transmittance of 30%.

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