A calibration system and method for voltage amplitude, amplitude-frequency characteristics and scanning speed of a medical electrocardiosignal monitoring device

Abstract

This invention discloses a calibration system and method for voltage amplitude, amplitude-frequency characteristics, and scanning speed of a medical electrocardiogram (ECG) signal monitoring device. The steps are as follows: placing a transparent ruler with scales on the screen of the monitoring device; inputting a standard square wave signal, sine wave signal, or ECG signal as required by the procedure into the monitoring device, displaying the input waveform on the screen; freezing the waveform on the screen; capturing a picture of the multi-parameter monitor screen using a camera to obtain a composite image of the waveform and the transparent ruler; and using image analysis software to obtain the voltage amplitude, amplitude-frequency characteristics, and scanning speed of the waveform signal in the composite image. This invention places a transparent ruler above the monitoring device screen, simultaneously acquiring the waveform on the screen and the ruler through photography or recording, and then using computer software for image processing, making the measurement data more intuitive and clear, improving measurement accuracy, and meeting the requirements for traceability to higher standards.

Description

Technical Field

[0001] This invention relates to the field of medical device metrology and calibration technology, and more specifically, to a calibration system and method for the voltage amplitude, amplitude-frequency characteristics, and scanning speed of a medical electrocardiogram signal monitoring device. Background Technology

[0002] In the metrological calibration of voltage amplitude, amplitude-frequency characteristics, and scanning speed of input standard waveforms in medical electrocardiogram (ECG) monitoring equipment such as multi-parameter monitors or ECG machines, the relevant verification procedures specify a steel ruler as the standard for measuring voltage amplitude, amplitude-frequency characteristics, and scanning speed, with a range of (0 ~ 150) mm and a graduation of 0.5 mm. However, in actual measurements, due to varying observer angles, the black background color of the monitor screen, the brightness of the waveform, and its thickness all affect the observation. Waveform amplitudes within 1 mm can only be estimated by visual inspection, resulting in significant human error and high uncertainty in the measurement results.

[0003] In view of the above, this application is hereby submitted. Summary of the Invention

[0004] The existing technology has the problem that waveform calibration of multi-parameter monitors or electrocardiographs is carried out by directly measuring and reading the waveform on the LCD screen with a ruler, which results in large errors and inaccurate measurement results. In order to solve the above-mentioned problems of the existing technology, the present invention provides a calibration system and method for voltage amplitude, amplitude-frequency characteristics and scanning speed of medical electrocardiogram signal monitoring equipment. A transparent scale is set above the screen of the medical electrocardiogram signal monitoring equipment. The waveform on the screen and the scale are simultaneously acquired by taking pictures or recording. Then, computer software is used for image processing to make the measurement data more intuitive and clear, improve the measurement accuracy, and meet the requirements of traceability to higher standards.

[0005] This invention is achieved through the following technical solution: In a first aspect, the present invention provides a calibration method for the voltage amplitude, amplitude-frequency characteristics, and scanning speed of a medical electrocardiogram signal monitoring device, comprising the following steps: (1) Place a transparent ruler with scale on the screen of a multi-parameter monitor or electrocardiograph, making it perpendicular to the top and bottom edges or left and right edges of the screen; (2) Connect the standard device (multi-parameter physiological simulator or electrocardiogram simulator), input the standard square wave signal, sine wave signal or electrocardiogram signal required by the procedure into the multi-parameter monitor or electrocardiograph, adjust the monitor setting parameters according to the procedure, and make the input waveform display normally on the screen of the multi-parameter monitor or electrocardiograph; (3) Use the freeze function of the multi-parameter monitor or electrocardiograph to freeze the waveform on the screen of the multi-parameter monitor or electrocardiograph. Use the shooting device to take pictures of the screen of the multi-parameter monitor or electrocardiograph to obtain a composite graphic of the waveform and the transparent scale. After taking the picture, save the image file and import it into the measurement and analysis software later. (4) After importing the file into the image analysis software, zoom in or out of the image, adjust the image contrast, call up the scale calibration function in the software, select the 10mm, 5mm and 1mm spacing on the high-precision transparent scale for calibration, after calibration, select the input waveform signal point to measure the amplitude height and period length according to the procedure requirements, and finally calculate the waveform signal voltage amplitude, amplitude frequency characteristics and scanning speed according to the procedure requirements.

[0006] This invention places a transparent scale above the screen of a multi-parameter monitor or electrocardiograph. The waveform on the screen and the scale are simultaneously captured by taking a picture or recording a video. Then, computer software is used for image processing to make the measurement data more intuitive and clear, improve the measurement accuracy, and meet the requirements for traceability to higher standards.

[0007] In one specific embodiment, the screen of the multi-parameter monitor or electrocardiograph is placed horizontally.

[0008] In one specific implementation, the imaging device takes pictures from above the screen of a multi-parameter monitor or electrocardiograph.

[0009] In one specific embodiment, the shooting device is a mobile phone or a camera.

[0010] Secondly, the present invention provides a calibration system for a calibration method of voltage amplitude, amplitude-frequency characteristics and scanning speed of a medical electrocardiogram signal monitoring device, comprising a support platform, wherein a support rod for mounting a multi-parameter monitor or electrocardiograph is provided on the support platform, and a mobile phone / camera bracket is provided above the support platform for mounting a mobile phone or camera to photograph the screen of the multi-parameter monitor or electrocardiograph.

[0011] In one specific embodiment, the support platform is provided with a support rod groove, and the lower end of the support rod is slidably installed in the support rod groove, which enables the support rod to move back and forth in the horizontal direction.

[0012] In one specific embodiment, the bracket platform is provided with a camera bracket slide groove perpendicular to the support rod slide groove, and a vertical camera support rod is provided on the camera bracket slide groove, which enables the camera support rod to move back and forth in a horizontal direction perpendicular to the direction of movement of the support rod, and the mobile phone / camera bracket is mounted on the camera support rod.

[0013] In one specific embodiment, horizontal adjustment knobs are installed at both ends of the support platform for leveling the support platform.

[0014] In one specific embodiment, a level is also installed on the support platform.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects: This invention provides a calibration system and method for voltage amplitude, amplitude-frequency characteristics, and scanning speed of a medical electrocardiogram (ECG) signal monitoring device. A transparent scale is set above the screen of a multi-parameter monitor or ECG machine. The waveform on the screen and the scale are simultaneously acquired by taking a picture or recording. Then, computer software is used for image processing to make the measurement data more intuitive and clear, improve the measurement accuracy, and meet the requirements for traceability to higher standards. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a top view of the calibration system structure provided in an embodiment of the present invention; Figure 2 A side view of the calibration system structure provided in an embodiment of the present invention; Figure 3 A flowchart of the calibration method provided in an embodiment of the present invention; Figure 4 A high-precision transparent scale ruler provided for embodiments of the present invention; Figure 5 The measurement and analysis software provided in this embodiment of the invention is used to measure a square wave 2Hz / 1mV, with the measurement unit being mm. Figure 6 The measurement and analysis software provided in this embodiment of the invention is used to measure a 10Hz / 1mV sine wave, with the measurement unit being mm. Figure 7 The measurement and analysis software provided in this embodiment of the invention is used to measure a 25Hz / 2mV sine wave. The measurement unit is mm. Figure 8 The images are actual square wave and sine wave images captured during actual measurements, provided for embodiments of the present invention. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0019] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known materials or methods have not been specifically described in order to avoid obscuring the invention.

[0020] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0021] Example 1 like Figure 1 and Figure 2 As shown, this embodiment of the invention provides a calibration system for the voltage amplitude, amplitude-frequency characteristics and scanning speed of a multi-parameter monitor or electrocardiograph, including an adjustable horizontal support platform 01, a support rod 02, a mobile phone / camera bracket 03, a camera support rod 04, a support rod slide 05, a level 06, a high-precision transparent ruler 07, and measurement and analysis software 08. A support platform 01 is provided, on which a support rod 02 for mounting a multi-parameter monitor or electrocardiograph is provided, and a mobile phone / camera bracket 03 is provided above the support platform 01 for mounting a mobile phone or camera to take pictures of the screen of the multi-parameter monitor or electrocardiograph.

[0022] The support platform 01 is provided with a support rod groove 05, and the lower end of the support rod 02 is slidably installed in the support rod groove 05, which enables the support rod 02 to move back and forth in the horizontal direction.

[0023] The bracket platform 01 is provided with a camera bracket slide groove 05 perpendicular to the support rod slide groove 05. A vertical camera support rod 04 is provided on the camera bracket slide groove 05, which can realize the camera support rod 04 moving back and forth in a horizontal direction perpendicular to the moving direction of the support rod 02. The mobile phone / camera bracket 03 is mounted on the camera support rod 04.

[0024] The support platform 01 is equipped with horizontal adjustment knobs 08 at both ends for leveling the support platform 01.

[0025] A level 06 is also installed on the support platform 01.

[0026] Example 2 This invention provides a calibration method for the voltage amplitude, amplitude-frequency characteristics, and scanning speed of a multi-parameter monitor, comprising the following steps: Step S01: Place the multi-parameter monitor (hereinafter referred to as the monitor) flat on the support platform, adjust the support rod and base knob of the support platform to keep the display screen horizontal and the orientation upright; connect the standard equipment (multi-parameter physiological simulator or electrocardiogram simulator) to input the square wave and sine wave signals required by the procedure; set the monitor function parameters according to the procedure to make the input waveform display normally on the monitor screen.

[0027] Step S02: Place the high-precision transparent ruler on the monitor screen, ensuring it is perpendicular to the top and bottom edges or left and right edges of the screen.

[0028] Step S03: Place the phone or camera on the phone / camera holder to keep it stable.

[0029] Step S04: Adjust the focus of your mobile phone or camera to capture the waveform on the monitor screen; save the image file after capturing the waveform, and then import it into the measurement and analysis software.

[0030] Step S05: After importing the file into the measurement and analysis software, zoom in or out on the image and adjust the image contrast.

[0031] Step S06, First step: Call up the scale calibration function in the software, select the captured measurement image, and measure and calibrate the 10mm, 5mm, and 1mm spacings on the high-precision transparent scale respectively. The software will automatically calculate and store the actual distance of the image.

[0032] Step S07, second step: Select waveform signal points on the standard waveform (square wave, sine wave) on the captured measurement image according to the procedure requirements, measure the amplitude height and period length, and record the measured values ​​of each parameter.

[0033] Step S08: After the measurement is completed, calculate the voltage amplitude, amplitude-frequency characteristics and various measured values ​​of different scanning speeds for different gain levels of the monitor according to the procedure requirements.

[0034] Among them, the voltage measurement error is calculated as follows:

[0035] Where: δ v Voltage measurement error, %; V i The monitor measures the voltage value in mV. V0: Output voltage value of the ECG simulator, mV; Among them, the amplitude-frequency characteristic error is calculated as follows:

[0036] Where: δ f : Relative error of amplitude-frequency response, % H x When the frequency is not 10Hz, it deviates from H 10 The waveform amplitude value corresponding to the largest value, in mV; H 10 Frequency is 10 At Hz, the waveform amplitude value displayed on the monitor screen, in mV; Among them, the scanning speed error is calculated as follows: The analog transmitter outputs a standard square wave with a frequency of 2Hz and an amplitude of 1mV to the monitor. The monitor's scan speed is set to 25mm / s, and four complete cycles are measured.

[0037] In the formula: V s Scanning speed, mm / s; L: Display width corresponding to 4 complete waveform cycles, in mm; t: The time corresponding to 4 complete cycles of the waveform, t = 2s; Calculate the scanning speed error using the following formula:

[0038] In the formula: δv s Scanning speed, mm / s; v s V 0: The scanning speed setting value for the device under inspection. V 0 = 25 mm / s; For monitors with a scanning speed of 50 mm / s, the scanning speed should be verified by measuring the display width corresponding to two complete waveform cycles, as described above.

[0039] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method of calibrating the voltage amplitude, amplitude-frequency characteristic and scan speed of a medical electrocardiosignal monitoring device, characterized in that, Includes the following steps: (1) Place the transparent ruler with scale on the screen of the medical electrocardiogram signal monitoring device; (2) Input the standard square wave signal, sine wave signal or electrocardiogram signal required by the procedure into the medical electrocardiogram signal monitoring equipment so that the input waveform is displayed on the screen of the multi-parameter monitor; (3) Freeze the waveform on the screen of the medical electrocardiogram signal monitoring device, and use a camera to capture the screen of the medical electrocardiogram signal monitoring device to obtain a composite image of the waveform and the transparent scale. (4) Use image analysis software to obtain the voltage amplitude, amplitude-frequency characteristics and scanning speed of the waveform signal in the composite image.

2. The calibration method of the voltage amplitude, amplitude-frequency characteristic and scanning speed of a medical ECG signal monitoring device according to claim 1, characterized in that, The screen of the medical electrocardiogram signal monitoring device is placed horizontally.

3. The method of calibrating the voltage amplitude, amplitude-frequency characteristic and scan speed of a medical ECG signal monitoring device according to claim 2, characterized in that, The camera takes pictures from above the screen of the medical electrocardiogram (ECG) signal monitoring device.

4. The calibration method for voltage amplitude, amplitude-frequency characteristics, and scanning speed of the medical electrocardiogram signal monitoring device according to claim 1, characterized in that, The shooting device is a mobile phone or a camera.

5. The calibration method for voltage amplitude, amplitude-frequency characteristics, and scanning speed of the medical electrocardiogram signal monitoring device according to claim 1, characterized in that, The specific method of step (4) is as follows: In the measurement and analysis software, first select the 10mm, 5mm and 1mm spacing on the high-precision transparent scale in the composite graphic for calibration. After calibration, select the input waveform signal point to measure the amplitude height and period length according to the procedure requirements. Finally, calculate the waveform signal voltage amplitude, amplitude frequency characteristics and scanning speed according to the procedure requirements.

6. A calibration system for implementing the calibration method for voltage amplitude, amplitude-frequency characteristics, and scanning speed of the medical electrocardiogram signal monitoring device according to any one of claims 1-5, characterized in that, Includes a support platform (01), on which a support rod (02) for installing a medical electrocardiogram signal monitoring device is provided, and a mobile phone / camera bracket (03) is provided above the support platform (01) for installing a mobile phone or camera to photograph the screen of the medical electrocardiogram signal monitoring device.

7. The calibration system according to claim 6, characterized in that, The support platform (01) is provided with a support rod groove (05), and the lower end of the support rod (02) is slidably installed in the support rod groove (05), which enables the support rod (02) to move back and forth in the horizontal direction.

8. The calibration system according to claim 7, characterized in that, The bracket platform (01) is provided with a camera bracket slide groove (05) perpendicular to the support rod slide groove (05). A vertical camera support rod (04) is provided on the camera bracket slide groove (05), which enables the camera support rod (04) to move back and forth in a horizontal direction perpendicular to the moving direction of the support rod (02). The mobile phone / camera bracket (03) is installed on the camera support rod (04).

9. The calibration system according to claim 6, characterized in that, The support platform (01) is equipped with horizontal adjustment knobs (08) at both ends for leveling the support platform (01).

10. The calibration system according to claim 9, characterized in that, A level (06) is also installed on the support platform (01).

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