A measuring device for pulse wave velocity

Abstract

The embodiment of the application provides a kind of for pulse wave velocity measuring device, it is related to health detection device technical field, for improving the accuracy and reliability of measurement result is poor, the problem of greater difficulty of measurement operation.The measuring device includes connecting support and two sensing units spaced apart in the first direction on the connecting support, and the sensing unit includes mounting structure, cascaded optical fiber structure and elastic structure.The mounting structure is provided with mounting slot, and the side of the mounting slot in the third direction has slot opening;The cascaded optical fiber structure includes first single-mode optical fiber, multimode optical fiber and second single-mode optical fiber connected in sequence, the cascaded optical fiber structure penetrates the mounting slot along the second direction, and the multimode optical fiber is located in the mounting slot;The elastic structure includes filling part and exposed part, the filling part is filled in the mounting slot, and the filling part and the exposed part are connected at the slot opening, and the exposed part is located outside the mounting slot.The above-mentioned measuring device can be applied to PWV measurement.

Description

Technical Field

[0001] This application relates to the field of health monitoring device technology, and in particular to a device for measuring pulse wave velocity. Background Technology

[0002] When the heart contracts, blood is pumped into the arteries, generating a pressure wave. This pressure wave propagates along the arterial walls, forming a pulse wave. By measuring the distance and time it takes for the pulse wave to travel through the arteries, the pulse wave velocity (PWV) can be calculated. PWV comprehensively reflects the damage to blood vessels caused by various risk factors and is a simple, effective, and economical non-invasive indicator for assessing arterial stiffness. Therefore, measuring PWV is of great significance for understanding arterial function and predicting and treating cardiovascular diseases such as hypertension and arteriosclerosis.

[0003] As described above regarding pulse wave velocity, its measurement requires capturing pulse wave signals at two measurement points on the artery. The pulse wave velocity is then calculated based on the time difference between the pulse wave signals at the two measurement points and the distance between them. In medical practice, sensor devices such as pressure sensors, ultrasound sensors, or photoelectric sensors are typically placed on the arterial surface to capture pulse wave signals by detecting the pulsation of the arterial wall. Common measurement point combinations include carotid-femoral artery, brachial-ankle artery, carotid-radial artery, and brachial-posterior tibial artery. For example, the carotid-femoral pulse wave velocity (cfPWV) between the carotid and femoral arteries is often considered the gold standard for measuring the degree of arteriosclerosis.

[0004] However, the methods for measuring pulse wave velocity using the aforementioned combination of measurement points are all regional pulse wave velocity measurement methods, yielding an average pulse wave velocity across different arteries. These methods are susceptible to variations in arterial separation and the influence of multiple pulse wave reflections between different arteries. Furthermore, the aforementioned sensor devices are easily affected by environmental factors, resulting in poor accuracy and reliability of the measurement results. Additionally, these methods require specialized medical equipment and the identification of two measurement points located on different arteries, making the measurement operation quite complex. Summary of the Invention

[0005] This application provides a device for measuring pulse wave velocity, which improves the problems of poor accuracy and reliability of measurement results and high difficulty in measurement operation.

[0006] To achieve the above objectives, this application provides a device for measuring pulse wave velocity. The device includes a connecting bracket and two sensing units spaced apart on the connecting bracket along a first direction. The sensing units include a mounting structure, a cascaded fiber optic structure, and an elastic structure.

[0007] The mounting structure is provided with a mounting slot, which has a slot opening on the third-direction side; the cascaded fiber structure includes a first single-mode fiber, a multimode fiber, and a second single-mode fiber connected in sequence, the cascaded fiber structure passes through the mounting slot along the second direction, and the multimode fiber is located in the mounting slot; the elastic structure includes a filling part and an exposed part, the filling part fills the mounting slot and wraps the multimode fiber, the filling part and the exposed part are connected at the slot opening, and the exposed part is located outside the mounting slot.

[0008] Among them, the first direction, the second direction, and the third direction are all perpendicular to each other.

[0009] In the measurement device employing the above design, the sensing unit detects pulse waves based on the relationship between the deformation of the multimode fiber in the cascaded fiber structure and the optical power of the output optical signal. This design achieves good linear pressure response over a wide pressure range, resulting in good detection sensitivity and accuracy. Furthermore, it is less affected by environmental factors and electromagnetic interference, leading to better reliability and stability of the detection results. Additionally, using a photodetector to detect the optical power of the output optical signal from the cascaded fiber structure offers advantages such as simple structure, small size, and low cost.

[0010] In the measurement device employing the above design, the sensing unit also incorporates an elastic structure that works in conjunction with the cascaded fiber optic structure. During detection, this elastic structure comes into contact with the user's skin. By incorporating the elastic structure, effective protection of the cascaded fiber optic structure can be achieved, ensuring its reliability. Furthermore, a connection channel can be established between the user's skin and the cascaded fiber optic structure. The pulse of an artery causes micro-deformation in the elastic structure, which transmits this micro-deformation to the multimode fiber of the cascaded fiber optic structure. Compared to the cascaded fiber optic structure directly contacting the user's skin, the elastic structure amplifies the amount of micro-deformation while transmitting it, thus making the detection of pulse waves by the cascaded fiber optic structure more sensitive and accurate.

[0011] On the other hand, the elastic structure is beneficial because its own elastic deformation characteristics can help the cascaded fiber structure to recover to its initial state in a timely manner after micro-deformation. This helps the cascaded fiber structure maintain the accuracy and reliability of the detection results in multiple measurements of pulse waves.

[0012] In addition, the exposed portion of the elastic structure comes into direct contact with the user's skin, making the contact more comfortable and thus improving the user experience.

[0013] In the measurement device using the above design, two sensing units are spaced apart on the connecting bracket. This design allows for the connection of the two sensing units together via the connecting bracket, facilitating an integrated measurement device design. An integrated device reduces operational complexity during measurement, for example, enabling the simultaneous determination of two test points. Furthermore, it can be applied to scenarios involving pulse wave velocity measurement on a single artery, improving the accuracy and reliability of the measurement results compared to regional pulse wave velocity measurement methods.

[0014] In some possible implementations, the two sensing units are designated as a first sensing unit and a second sensing unit, respectively, and the connecting bracket is an adjustable bracket structure capable of adjusting the distance between the first sensing unit and the second sensing unit in a first direction. By adjusting the distance between the first sensing unit and the second sensing unit, it is possible to match the distance differences between the same two measurement points for different users, and also to match the distance differences between the same user for different two measurement points, thereby meeting different measurement requirements and improving the applicability of the measuring device.

[0015] In some possible implementations, the connecting bracket includes a sliding rod, a drive block, a drive structure, a first transmission rod, and a second transmission rod.

[0016] The sliding rod extends along a first direction, the first sensing unit is fixedly connected to the sliding rod, and the second sensing unit is slidably disposed on the sliding rod; the driving block is located between the first sensing unit and the second sensing unit, and the driving structure is connected to the driving block for driving the driving block to move along a second direction.

[0017] One end of the first transmission rod is rotatably connected to the first sensing unit about a third direction, and the other end is rotatably connected to the drive block about a third direction; one end of the second transmission rod is rotatably connected to the second sensing unit about a third direction, and the other end is rotatably connected to the drive block about a third direction.

[0018] The connecting bracket adopts the above design to realize the function of adjusting the spacing, which has the advantages of simple structure, easy implementation, high motion reliability and low cost.

[0019] In some possible implementations, the drive structure includes a mounting block and a drive rod, with the mounting block and drive block spaced apart in a second direction. The drive rod extends along the second direction, rotatably passes through the mounting block about the second direction, and is threadedly engaged with the drive block. The drive structure, using the above design, achieves the function of moving the drive block along the second direction, and has advantages such as simple structure, ease of implementation, high motion reliability, and low cost.

[0020] In some possible implementations, the connecting bracket may also include a third drive rod and a fourth drive rod.

[0021] One end of the third transmission rod is rotatably connected to the first sensing unit in a third direction, and the other end is rotatably connected to the mounting block in a third direction; one end of the fourth transmission rod is rotatably connected to the second sensing unit in a third direction, and the other end is rotatably connected to the mounting block in a third direction.

[0022] By adding a third and a fourth transmission rod, the stability and reliability of the first and second sensing units during the spacing adjustment process can be improved by connecting the bracket.

[0023] In some possible implementations, the drive rod includes a rotation actuation part in the portion relative to the mounting block that is away from the drive block. Alternatively, the drive structure further includes a drive motor connected to the drive rod for driving the drive rod to rotate relative to the mounting block about a second direction.

[0024] This shows that the drive rod in the drive structure can be driven manually or electrically. In other words, the distance between the first and second sensing units can be adjusted manually or electrically, offering a flexible design suitable for various applications, such as adaptive measurement through electrically adjusted distances.

[0025] In some possible implementations, the connecting bracket includes a sliding rod and a driving rod, both of which extend along a first direction.

[0026] The first sensing unit is fixedly connected to the sliding rod, and the second sensing unit is slidably mounted on the sliding rod; the driving rod is rotatably mounted on the first sensing unit in a first direction and is threadedly engaged with the second sensing unit.

[0027] The connecting bracket adopts the above design to realize the function of adjusting the spacing, which has the advantages of simple structure, easy implementation, high motion reliability and low cost.

[0028] In some possible implementations, the drive rod includes a rotation operation part in the portion of the drive rod that is away from the second sensing unit relative to the first sensing unit; or, the connecting bracket further includes a drive motor connected to the drive rod for driving the drive rod to rotate about a first direction relative to the first sensing unit.

[0029] This shows that the drive rod in the drive structure can be driven manually or electrically. In other words, the distance between the first and second sensing units can be adjusted manually or electrically, offering a flexible design suitable for various applications, such as adaptive measurement through electrically adjusted distances.

[0030] In some possible implementations, the distance between the first sensing unit and the second sensing unit in the first direction is adjustable from 6 mm to 35 mm under the action of the connecting bracket.

[0031] When the connecting bracket in the measuring device can achieve the above-mentioned adjustable spacing range, it can meet the application scenario of measuring pulse wave velocity on the radial artery, with any two of the cun, guan and chi positions as two measurement points.

[0032] In some possible implementations, the connecting bracket is a fixed bracket structure, and the distance between the two sensing units in the first direction is fixed. This design helps to ensure the consistency of the distance between the two sensing units and facilitates the calibration of the distance.

[0033] In some possible implementations, the distance between the two sensing units in the first direction is 6 mm to 35 mm. When the connecting bracket in the measuring device can achieve the above-mentioned distance, it can meet the application scenario of measuring pulse wave velocity on the radial artery, with any two of the cun, guan, and chi positions as the two measurement points.

[0034] In some possible implementations, the material of the elastic structure includes polydimethylsiloxane or silicone. This design allows the elastic structure to have good elastic properties and improves comfort when in contact with the user's skin, while also offering advantages such as ease of processing and low cost.

[0035] In some possible implementations, the exposed portion has a sensing contact surface that bulges outward relative to the slot opening, and this sensing contact surface includes a smoothly transitioned arcuate surface. This design further enhances comfort when in contact with the user's skin, thereby improving the user experience.

[0036] In some possible implementations, the sensing unit further includes a sensitivity-enhancing structure disposed on the bottom surface opposite the mounting slot and slot opening, comprising multiple sensitivity-enhancing protrusions spaced apart in a second direction. By providing the sensitivity-enhancing structure, multiple spaced support points can be formed below the cascaded fiber structure through the multiple sensitivity-enhancing protrusions. Under the same pulse beat, compared to not having a sensitivity-enhancing structure, the multiple spaced support points formed by the sensitivity-enhancing structure can cause greater deformation of the multimode fiber in the cascaded fiber structure, thereby amplifying the micro-deformation caused by the pulse beat and increasing the amplitude of optical power change caused by the same pulse beat. This makes the cascaded fiber structure more accurate and sensitive in detecting pulse beats, thus improving the accuracy and sensitivity of pulse wave detection.

[0037] In some possible implementations, the cross-sectional shape of the sensitizing protrusion in the reference plane is triangular, quadrilateral, pentagonal, or hexagonal; wherein the reference plane is parallel to the first direction and the third direction. It can be seen that the sensitizing structure can employ sensitizing protrusions of various shapes, offering flexible design and adaptability to different application scenarios.

[0038] In some possible implementations, the measuring device also includes a vibration damping structure made of cushioning material, mounted on a connecting bracket and positioned between the two sensing units. This design prevents external vibrations from affecting the sensing units and thus the accuracy of the detection results.

[0039] In some possible implementations, the measuring device further includes a restraint structure and a vibration damping structure. The restraint structure is connected to the connecting bracket and is used to secure the connecting bracket to the human body. The vibration damping structure, made of cushioning material, is positioned between the restraint structure and the connecting bracket. This design prevents external vibrations from affecting the sensing unit through the restraint structure, thereby affecting the accuracy of the detection results.

[0040] In some possible implementations, the multimode fiber extends 5mm to 15mm along the second direction within the mounting slot. When the cascaded fiber structure in the sensing unit uses multimode fiber of the aforementioned length, it can meet the detection sensitivity requirements within common pulse pressure ranges for different users, achieving good linear pressure response under different pulse pressure conditions. This allows it to adapt to different detection needs and improves the applicability of the sensing unit.

[0041] In some possible implementations, the measuring device is used to measure pulse wave velocity on a single artery, and two sensing units are used to detect pulse waves at two measurement points on the single artery; the single artery is the radial artery, carotid artery, or femoral artery. Compared to regional pulse wave velocity measurement methods that measure pulse wave velocity on different arteries, local pulse wave velocity measurement methods that measure pulse wave velocity on a single artery have relatively smaller measurement errors, and the propagation of the pulse wave is much less affected by reflected pulse waves, thus the measurement results are more accurate.

[0042] In some possible implementations, the measuring device is used to measure pulse wave velocity on the radial artery, and any two of the cun, guan, and chi portions of the radial artery are used as two measurement points for two sensing units.

[0043] This design has several advantages. First, because the pulse is more pronounced at the cun, guan, and chi positions of the radial artery, the measurement points can be quickly and accurately determined. This greatly simplifies the pulse wave velocity measurement process, reducing operational difficulty and improving the user experience. Furthermore, the pronounced pulse beats are more easily detected by the sensing unit, which helps generate a pulse wave signal with a higher signal-to-noise ratio, thus improving the accuracy of the pulse wave velocity measurement results.

[0044] On the other hand, Traditional Chinese Medicine (TCM) theory holds that the cun, guan, and chi points on the radial artery correspond to different internal organs in the human body. By analyzing the pulse patterns at these points, the functional status of the corresponding organs can be inferred. Therefore, using the cun, guan, and chi points on the radial artery as measurement points has unique advantages in TCM clinical practice, enabling comprehensive analysis in conjunction with TCM theory and improving diagnostic accuracy.

[0045] Furthermore, since the radial artery is located at the wrist, the detection module (the collective term for the connecting bracket and two sensing units) can be placed on the wrist during measurement, making it relatively easy to measure and avoiding any uncomfortable experience such as pressure on the user. Also, because the cun, guan, and chi points are relatively short, using these points as measurement points facilitates the integration and miniaturization of the measuring device. This integration and miniaturization allows for wearable designs, such as wristwatches or bracelets. Wearable designs enable daily and long-term measurement of the user's pulse wave velocity.

[0046] In some possible implementations, the measuring device also includes a laser source, a beam splitter, two photodetectors, and a processing device.

[0047] A laser source is used to generate an optical signal that is output to a beam splitter. The beam splitter is used to split the optical signal and input it into a cascaded fiber structure in two sensing units. Two photodetectors are used to detect the optical signals output from the two cascaded fiber structures respectively. The processing device is configured to calculate the pulse wave velocity based on the detection results of the two photodetectors.

[0048] The measuring device, employing the aforementioned design, offers advantages such as simple structure, low cost, and high reliability. Furthermore, the laser source, beam splitter, photodetector, and processing unit can all be integrated, facilitating the miniaturization and integration of the measuring device.

[0049] In some possible implementations, the measuring device is a smart wearable device. Smart wearable devices facilitate daily and long-term measurement of pulse wave velocity, thereby enabling users to manage their health. Attached Figure Description

[0050] Figure 1 This is a schematic diagram of the structure of a measuring device provided in an embodiment of this application;

[0051] Figure 2 This is a schematic diagram of the structure of a detection module provided in an embodiment of this application;

[0052] Figure 3 for Figure 2 Exploded view of the detection module;

[0053] Figure 4 for Figure 3 A schematic diagram of the installation structure in the middle;

[0054] Figure 5 This is a schematic diagram of a cascaded optical fiber structure provided in an embodiment of this application;

[0055] Figure 6 This is a schematic diagram of an elastic structure provided in an embodiment of this application;

[0056] Figure 7 for Figure 4 Schematic diagram of the arrangement of the sensitizing structure;

[0057] Figure 8 This is a schematic diagram illustrating the application of a measuring device provided in an embodiment of this application;

[0058] Figure 9 for Figure 2 A schematic diagram of the detection module from another angle;

[0059] Figure 10 for Figure 2 A schematic diagram of the vibration damping structure installed in the detection module;

[0060] Figure 11 This is a schematic diagram illustrating the connection between another connecting bracket and two mounting structures provided in an embodiment of this application;

[0061] Figure 12 for Figure 11 A schematic diagram of the vibration damping structure in the middle structure;

[0062] Figure 13 This is a schematic diagram of a data processing method provided in an embodiment of this application. Detailed Implementation

[0063] The technical solutions of the embodiments of this application will now be described with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them.

[0064] In the following embodiments of this application, the terms "first," "second," etc., are used for descriptive convenience only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.

[0065] In the embodiments of this application, "upper", "lower", "left" and "right" are not limited to the orientation of the components in the accompanying drawings. It should be understood that these directional terms can be relative concepts, used for relative description and clarification, and can change accordingly depending on the orientation of the components in the accompanying drawings.

[0066] In the embodiments of this application, unless the context otherwise requires, the term "comprising" is interpreted as open and encompassing throughout the specification and claims, meaning "including, but not limited to." In the description of the specification, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "exemplarily," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this application. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics mentioned may be included in any suitable manner in any one or more embodiments or examples.

[0067] As used herein, “about,” “approximately,” or “approximately” includes the stated value and the average value within an acceptable range of deviation from the given value, wherein the acceptable range of deviation is determined by a person skilled in the art taking into account the measurement under discussion and the error associated with the measurement of the given quantity (i.e., the limitations of the measurement system).

[0068] As used herein, “parallel,” “perpendicular,” and “equal” include the described situation and situations that are similar to the described situation, within an acceptable range of deviation, which is determined by those skilled in the art taking into account the measurement under discussion and the error associated with the measurement of a particular quantity (i.e., the limitations of the measurement system). For example, “parallel” includes absolute parallelism and approximate parallelism, where an acceptable range of deviation for approximate parallelism may be, for example, within 5°; “perpendicular” includes absolute perpendicularity and approximate perpendicularity, where an acceptable range of deviation for approximate perpendicularity may also be, for example, within 5°; “equal” includes absolute equality and approximate equality, where an acceptable range of deviation for approximate equality may be, for example, a difference between the two equals being less than or equal to 5% of either one.

[0069] It should be understood that when a layer or element is referred to as being on another layer or substrate, it can mean that the layer or element is directly on the other layer or substrate, or that there is an intermediate layer between the layer or element and the other layer or substrate.

[0070] Exemplary embodiments are described in this application with reference to cross-sectional views and / or plan views and / or equivalent circuit diagrams, which are idealized exemplary drawings. In the drawings, the thickness of layers and regions is enlarged for clarity. Therefore, variations in shape relative to the drawings are contemplated due to, for example, manufacturing techniques and / or tolerances. Thus, exemplary embodiments should not be construed as being limited to the shapes of the regions shown herein, but rather include shape deviations due to, for example, manufacturing processes. For example, etched regions shown as rectangular would typically have curved features. Therefore, the regions shown in the drawings are schematic in nature, and their shapes are not intended to show the actual shapes of the regions of the device, nor are they intended to limit the scope of the exemplary embodiments.

[0071] This application provides a device for measuring pulse wave velocity (PWV) (hereinafter referred to as the measuring device), such as Figure 1 As shown, the measuring device 1 includes a laser source 2, a beam splitter 3, a detection module 4, two photodetectors 6, and a processing device 7. The detection module 4 includes a connecting bracket 8 and two sensing units 5 spaced apart on the connecting bracket 8. The output of the laser source 2 is connected to the input of the beam splitter 3. The two outputs of the beam splitter 3 are respectively connected to the inputs of the two sensing units 5. The outputs of the two sensing units 5 are respectively connected to the two photodetectors 6. The outputs of both photodetectors 6 are connected to the processing device 7.

[0072] When the measuring device 1 is working, the laser source 2 generates the laser beam, i.e., the optical signal, required for the operation of the sensing unit 5. This optical signal is output to the beam splitter 3, which splits it into two and transmits them to the two sensing units 5 respectively. The sensing unit 5 can convert the pulse wave in the artery into changes in the optical power of the optical signal, thereby achieving the purpose of pulse wave detection (the specific principle can be referred to in the following description). The two sensing units 5 are used to detect the pulse wave at two measurement points on the user's artery respectively. Two photodetectors 6 are used to detect the optical power of the optical signals output by the two sensing units 5 respectively. The processing device 7 is configured to calculate the pulse wave velocity based on the optical power detection results of the two photodetectors 6 and the distance between the two sensing units 5.

[0073] In some embodiments, the measuring device 1 may also use two laser sources 2 instead of the combination of one laser source 2 and beam splitter 3 to provide optical signals to the two sensing units 5 respectively. The two laser sources 2 may be the same or different.

[0074] For ease of description, this paper will use the first direction, the second direction and the third direction that are mutually perpendicular to each other as references to illustrate the structure of the measuring device 1.

[0075] like Figure 2 and Figure 3 As shown, the sensing unit 5 includes a mounting structure 9, a cascaded fiber optic structure 11, and a flexible structure 10. The mounting structure 9 has a mounting groove 12 extending along a first direction X, a second direction Y, and a third direction Z. The mounting groove 12 has an opening on one side in the third direction Z, through which it communicates with the outside along the third direction Z. The mounting structure 9 also includes connecting holes 13 disposed opposite each other on both sides of the mounting groove 12 in the second direction Y, with both connecting holes 13 communicating with the mounting groove 12.

[0076] For example, such as Figure 3 and Figure 4 As shown, the mounting structure 9 is a cuboid structure, including a base plate 16 and a first side plate 20, a second side plate 14, a third side plate 17, and a fourth side plate 19 disposed on the same side of the base plate 16. The base plate 16 is a square plate parallel to the first direction X and the second direction Y. The first side plate 20 and the third side plate 17 are arranged opposite each other in the second direction Y, both being square plates parallel to the first direction X and the third direction Z. The second side plate 14 and the fourth side plate 19 are arranged opposite each other in the second direction Y, both being square plates parallel to the second direction Y and the third direction Z. The first side plate 20, the second side plate 14, the third side plate 17, and the fourth side plate 19 are sequentially connected to form a closed structure, thereby enclosing the base plate 16 to form a mounting groove 12 with a slot opening 15. The slot opening 15 is opposite to the base plate 16 and is located on the side of the mounting groove 12 away from the base plate 16 along the first direction X. The surface of the base plate 16 near the slot opening 15 is the bottom surface of the mounting groove 12. The two connecting holes 13 on the mounting structure 9 are respectively located on the first side plate 20 and the third side plate 17.

[0077] Please refer to Figure 3 and Figure 5 The cascaded fiber optic structure 11 is mounted on the mounting structure 9, employing a cascaded design of single-mode-multimode-single-mode (SMS) fiber optics, including a first single-mode fiber 21, a multimode fiber 22, and a second single-mode fiber 23 connected sequentially. Please also consider... Figure 1One end of the first single-mode fiber 21 is connected to the optical splitter 3 to receive the optical signal output by the optical splitter 3. Due to the limitation of single-mode fiber, the optical signal transmitted in the first single-mode fiber 21 is a single-mode optical signal. The other end of the first single-mode fiber 21 is connected to one end of the multimode fiber 22 to input the single-mode optical signal into the multimode fiber 22. When the single-mode optical signal enters the multimode fiber 22, it is converted into a multimode optical signal. The other end of the multimode fiber 22 is connected to the second single-mode fiber 23 to input the multimode optical signal into the second single-mode fiber 23. When the multimode optical signal enters the second single-mode fiber 23, it is converted into a single-mode optical signal again. The other end of the second single-mode fiber 23 is connected to the photodetector 6, which can detect the optical signal output from the second single-mode fiber 23 to obtain the optical power of the output optical signal.

[0078] Since multimode optical signals are transmitted in multimode fiber 22, multimode interference will occur between the multiple modes. When multimode fiber 22 deforms, the multimode interference changes, which in turn changes the optical power of the output optical signal of the cascaded fiber structure 11. The magnitude of the change in the optical power of the output optical signal is related to the magnitude of the deformation. In other words, there is a certain correspondence between the deformation of multimode fiber 22 in the cascaded fiber structure 11 and the optical power of the output optical signal. Based on this correspondence, the cascaded fiber structure 11 can be used to detect the pulsation of the arterial wall to capture the pulse wave signal, thereby achieving pulse wave detection. In addition, since single-mode fiber has a smaller core diameter, it is less susceptible to interference and has better stability. Therefore, the first single-mode fiber 21 and the second single-mode fiber 23 can be used as optical fibers to transmit the input and output optical signals in multimode fiber 22, thereby improving the signal-to-noise ratio of the optical signal.

[0079] like Figures 2 to 4 As shown, when the cascaded fiber structure 11 is installed with the mounting structure 9, the cascaded fiber structure 11 extends into the mounting groove 12 through one connection hole 13 and extends out through another connection hole 13. That is, the cascaded fiber structure 11 passes through the mounting groove 12 through the two connection holes 13 on the mounting structure 9. The portion of the cascaded fiber structure 11 in the mounting groove 12 is in a straightened state, that is, it extends along the second direction Y, and the multimode fiber 22 is located in the mounting groove 12.

[0080] Please refer to Figure 2 , Figure 3 , Figure 4 and Figure 6In the measuring device 1 provided in this embodiment, the elastic structure 10 is also mounted on the mounting structure 9. A portion of the elastic structure 10 fills the mounting groove 12 and wraps the cascaded fiber structure 11; another portion extends to the outside of the mounting groove 12 through the groove opening 15. For ease of description, the elastic structure 10 is divided into a filling portion 24 and an exposed portion 25 according to its location. The filling portion 24 is the part of the elastic structure 10 located in the mounting groove 12, and the exposed portion 25 is the part of the elastic structure 10 located outside the mounting groove 12. The filling portion 24 and the exposed portion 25 are connected at the groove opening 15, and the exposed portion 25 is disposed on the top of the filling portion 24 located at the groove opening 15.

[0081] The elastic structure 10 is made of elastic materials such as polydimethylsiloxane (PDMS) or silicone, and can be manufactured by casting.

[0082] For example, the manufacturing process of sensing unit 5 can be as follows:

[0083] 1. Insert the cascaded fiber optic structure 11 into the mounting groove 12 through one of the connection holes 13 in the mounting structure 9, and exit from the other connection hole 13;

[0084] 2. Straighten the portion of the cascaded fiber structure 11 located in the mounting groove 12, and position the multimode fiber 22 in the mounting groove 12;

[0085] 3. Use glue to firmly attach and fix the straightened cascaded fiber structure 11;

[0086] 4. Use elastic material to pour into the mounting groove 12 through the groove opening 15, and make the elastic material overflow the mounting groove 12 to form an elastic structure 10.

[0087] When detecting a user's artery pulse wave, the sensing unit 5 needs to be placed outside the user's artery, with the exposed portion 25 of the elastic structure 10 in direct contact with the skin outside the user's artery. The pulse wave generated when the heart contracts and pumps blood into the artery causes a perceptible pulsation in the arterial wall, i.e., a pulse beat. This pulse beat acts on the elastic structure 10, causing it to undergo micro-deformation. The micro-deformation of the elastic structure 10 is transmitted to the cascaded optical fiber structure 11 wrapped by it, causing the multimode optical fiber 22 in the cascaded optical fiber structure 11 to also undergo micro-deformation. This results in a change in the optical power of the output optical signal of the cascaded optical fiber structure 11. Based on this change in optical power, the pulse wave signal can be obtained, thereby realizing the detection of the pulse wave.

[0088] In the sensing unit 5 using the above design, the cascaded fiber optic structure 11 can be used to detect pulse waves. This detection structure and method can achieve good linear pressure response over a large pressure range, with good sensitivity and accuracy. Furthermore, it is less affected by environmental factors and electromagnetic interference, resulting in good reliability and stability of the detection results. Additionally, the output optical signal of the cascaded fiber optic structure 11 is detected using a photodetector 6, which offers advantages such as simple structure, small size, and low cost.

[0089] The sensing unit 5, designed as described above, also incorporates an elastic structure 10. Through the cooperation of the elastic structure 10 and the cascaded fiber optic structure 11, effective protection of the cascaded fiber optic structure 11 is achieved, ensuring its reliability. Furthermore, a connection channel is established between the user's skin and the cascaded fiber optic structure 11, transmitting the pulse of the artery to the multimode fiber 22 of the cascaded fiber optic structure 11. Compared to the cascaded fiber optic structure 11 directly contacting the user's skin, the elastic structure 10 amplifies the deformation while transmitting micro-deformations, thus making the detection of pulse waves by the cascaded fiber optic structure 11 more sensitive and accurate.

[0090] On the other hand, the elastic structure 10 is beneficial to use its own elastic deformation characteristics to drive the cascaded fiber structure 11 to recover to its initial state in a timely manner after micro-deformation, which is conducive to maintaining the accuracy and reliability of the detection results in multiple measurements of pulse waves by the cascaded fiber structure 11.

[0091] In addition, the exposed portion 25 of the elastic structure 10 is in direct contact with the user's skin, making the contact more comfortable and thus improving the user experience.

[0092] In some embodiments, such as Figure 6 As shown, the exposed portion 25 has a sensing contact surface 26 that protrudes outward relative to the slot opening 15. This sensing contact surface 26 includes a smoothly transitioned arcuate surface. By contacting the user's skin through this sensing contact surface 26, the comfort during skin contact can be further improved, thereby enhancing the user experience.

[0093] When the sensing unit 5 is designed to measure pulse waves at a specific measurement point, the sensing contact surface 26 of the exposed portion 25 can be specifically designed according to the skin characteristics at that specific measurement point, so that the extended contour of the sensing contact surface 26 is consistent with the extended contour of the skin at that specific measurement point.

[0094] In some embodiments, the exposed portion 25 in the elastic structure 10 includes a first portion and a second portion. The first portion covers the filling portion 24, and the second portion is located on the outer periphery of the first portion, covering the mounting structure 9 on the outer periphery of the slot opening 15, i.e., the top of the first side plate 20, the second side plate 14, the third side plate 17, and the fourth side plate 19 that is away from the bottom plate 16. This "cap"-shaped structure design can improve the connection stability between the elastic structure 10 and the mounting structure 9.

[0095] In some embodiments, such as Figure 4 and Figure 7 As shown, the sensing unit 5 also includes a sensitivity-enhancing structure 18, which is disposed on the bottom surface of the mounting groove 12, that is, on the inner surface of the base plate 16 in the mounting groove 12 in the mounting structure 9. The sensitivity-enhancing structure 18 includes a plurality of sensitivity-enhancing protrusions 27 spaced apart in the second direction Y. For example, the cross-sectional shape of the sensitivity-enhancing protrusions 27 in the reference plane is triangular, quadrilateral, pentagonal, or hexagonal, etc.; wherein, the reference plane is parallel to the first direction X and the third direction Z.

[0096] The sensitivity-enhancing protrusion 27 in the sensitivity-enhancing structure 18 is located below the cascaded fiber structure 11, that is, in the orthographic projection onto the bottom surface of the mounting groove 12, the cascaded fiber structure 11 overlaps with the sensitivity-enhancing structure 18. The cascaded fiber structure 11 is supported by the sensitivity-enhancing protrusion 27 in the sensitivity-enhancing structure 18.

[0097] The sensitivity-enhancing structure 18 designed above can form multiple spaced support points below the cascaded fiber structure 11 through multiple sensitivity-enhancing protrusions 27. Under the same pulse beat, compared with not having the sensitivity-enhancing structure 18, the multiple spaced support points formed by the sensitivity-enhancing structure 18 can cause greater deformation of the multimode fiber 22 in the cascaded fiber structure 11, thereby amplifying the micro-deformation caused by the pulse beat and increasing the amplitude of optical power change caused by the same pulse beat. This makes the detection of pulse beats by the cascaded fiber structure 11 more accurate and sensitive, thus improving the accuracy and sensitivity of pulse wave detection.

[0098] In some embodiments, the sensitizing protrusion 27 is a triangular prism, one side of which contacts the base plate 16, and another side is parallel to the first direction X and located at the top of the prism away from the base plate 16, i.e., at the position closest to the cascaded fiber structure 11. This design can further reduce the support area of ​​the sensitizing structure 18 on the cascaded fiber structure 11, and improve the ability of the sensitizing structure 18 to amplify micro-deformations.

[0099] Since pulse pressure may differ between different users at the same measurement point, and may also differ between the same user at different measurement points, the required pulse wave detection sensitivity of the sensing unit 5 varies depending on the pulse pressure. Furthermore, in the aforementioned sensing unit 5, the extension distance of the multimode optical fiber 22 in the mounting slot 12 along the second direction Y affects the sensitivity for pulse wave detection. Therefore, in some embodiments, the extension distance of the multimode optical fiber 22 in the mounting slot 12 along the second direction Y is designed to be 5mm to 15mm, for example, 5mm, 8mm, 10mm, 12mm, or 15mm.

[0100] The use of multimode fiber 22 of the above length can meet the detection sensitivity requirements of different users in the common pulse pressure range. It can achieve good linear pressure response under different pulse pressure conditions, thereby adapting to different detection needs and improving the applicability of the sensing unit 5.

[0101] In addition, the core diameter of the multimode fiber 22, the design of the elastic structure 10 (e.g., shape and size), and the design of the sensitizing structure 18 (if any) (e.g., the shape, size, number, and spacing of the sensitizing protrusions 27) will also affect the sensitivity of the sensing unit 5 to pulse wave detection. Based on this, the above designs can be comprehensively adjusted to improve the applicability of the sensing unit 5.

[0102] As described above, the measuring device 1 provided in this embodiment includes two sensing units 5. These two sensing units 5 are used to detect pulse waves at two test points, thereby measuring the pulse wave velocity. For ease of description, the two sensing units 5 in the measuring device 1 are referred to as the first sensing unit 51 and the second sensing unit 52, respectively. The mounting structure 9 in the first sensing unit 51 is referred to as the first mounting structure, and the mounting structure 9 in the second sensing unit 52 is referred to as the second mounting structure.

[0103] like Figure 2 As shown, the measuring device 1 also includes a connecting bracket 8, which is used to mount and fix two sensing units 5, namely a first sensing unit 51 and a second sensing unit 52. The first mounting structure in the first sensing unit 51 and the second mounting structure in the second sensing unit 52 are both connected to the connecting bracket 8. The first sensing unit 51 and the second sensing unit 52 mounted on the connecting bracket 8 are spaced apart in the first direction X. This spaced arrangement of the first sensing unit 51 and the second sensing unit 52 enables pulse wave detection at two measurement points.

[0104] In the measuring device 1 provided in this application embodiment, two sensing units 5 can be connected together by a connecting bracket 8 to achieve an integrated design of the two sensing units 5. This allows for the simultaneous determination of the positions of two measurement points, simplifying the operation during the measurement process. Furthermore, compared to sensor devices such as pressure sensors, ultrasonic sensors, or photoelectric sensors, the sensing unit 5 with the above-designed structure has higher sensitivity for pulse wave detection, and the accuracy and reliability of the detection results are significantly improved. Therefore, pulse wave velocity can be measured using two measurement points with a small distance between them, which is beneficial for the miniaturization of the measuring device 1.

[0105] The measuring device 1 provided in this application embodiment can be applied to measure pulse wave velocity on a single artery, such as the radial artery, femoral artery, or carotid artery. Measuring pulse wave velocity on a single artery involves selecting two measurement points on the same artery and determining the pulse wave velocity based on the detection results of these two points. This method of measuring pulse wave velocity on a single artery is commonly referred to as the local pulse wave velocity measurement method.

[0106] Compared to regional pulse wave velocity measurement methods that measure pulse wave velocity on different arteries, local pulse wave velocity measurement methods are performed on a single artery. The actual transmission distance of the pulse wave in the artery is closer to the distance between the two sensing units 5, making it easier to calibrate and resulting in a relatively smaller measurement error. Furthermore, the propagation of the pulse wave is much less affected by reflected pulse waves, thus leading to more accurate measurement results.

[0107] In some embodiments, such as Figure 8 As shown, the measuring device 1 can be used to measure pulse wave velocity on the radial artery, with any two of the three sections (cun, guan, and chi) on the radial artery serving as two measurement points. This design, on the one hand, allows for quick and accurate determination of measurement points because the pulse is more pronounced in the cun, guan, and chi sections of the radial artery; it greatly simplifies the pulse wave velocity measurement process, reducing operational difficulty and improving the user experience. Furthermore, the pronounced pulse beats are more easily detected by the sensing unit 5, which helps the sensing unit 5 generate a pulse wave signal with a higher signal-to-noise ratio, thereby improving the accuracy of the pulse wave velocity measurement results.

[0108] On the other hand, Traditional Chinese Medicine (TCM) theory holds that the cun, guan, and chi points on the radial artery correspond to different internal organs in the human body. By analyzing the pulse patterns at these points, the functional status of the corresponding organs can be inferred. Therefore, using the cun, guan, and chi points on the radial artery as measurement points has unique advantages in TCM clinical practice, enabling comprehensive analysis in conjunction with TCM theory and improving diagnostic accuracy.

[0109] On the other hand, because the radial artery is located at the wrist, such as Figure 8 As shown, the detection module 4 is placed on the wrist during measurement, making it easy to measure and avoiding any discomfort such as pressure on the user. Furthermore, the small length of the cun, guan, and chi sections facilitates the integration and miniaturization of the measuring device 1 when these sections are used as measurement points. This integrated and miniaturized design allows for wearable design, such as a wristwatch or bracelet. When the measuring device 1 is designed as a wearable device, it enables daily and long-term measurement of the user's pulse wave velocity.

[0110] For applications involving pulse wave velocity measurement on the radial artery, using any two of the three sections (cun, guan, and chi) as measurement points, the measuring device 1 can be adaptively designed. Specifically, the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X can be matched with the distance between the two target measurement points through the design of the connecting bracket 8.

[0111] According to statistics, the lengths of the radial artery in adults, specifically the cun, guan, and ulnar portions, range from 27.3 mm to 41.0 mm. Specifically, the cun portion is 8.62 mm to 12.9 mm long, the guan portion is 8.62 mm to 12.9 mm long, and the ulnar portion is 10.1 mm to 15.1 mm long.

[0112] For example, using the cun and guan points on the radial artery as two measurement points, the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X is designed to be 6mm to 20mm, such as 6mm, 7mm, 8mm, ..., 18mm, 19mm, or 20mm. With the above-mentioned spacing design, pulse wave detection can be performed on the cun and guan points of the radial artery using the first sensing unit 51 and the second sensing unit 52, respectively.

[0113] In another example, using the guan and ulnar portions of the radial artery as two measurement points, the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X is designed to be 6mm to 25mm, for example, 6mm, 7mm, 8mm, ..., 23mm, 24mm, or 25mm. With this spacing design, pulse wave detection can be performed on the guan and ulnar portions of the radial artery using the first sensing unit 51 and the second sensing unit 52, respectively.

[0114] As another example, using the cun and chi portions of the radial artery as two measurement points, the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X is designed to be 18mm to 35mm, for example, 18mm, 19mm, 20mm, ..., 33mm, 34mm, or 35mm. With this spacing design, pulse wave detection can be performed on the guan and chi portions of the radial artery using the first sensing unit 51 and the second sensing unit 52, respectively.

[0115] In the measuring device 1 provided in this application embodiment, the connecting bracket 8 can adopt an adjustable bracket structure. Here, "adjustable" means that the distance between the two transmission units in the first direction X can be adjusted within a certain range. For example... Figure 9 As shown, the connecting bracket 8 includes a sliding rod 28, a driving block 29, a driving structure 35, a first connecting rod 31, and a second connecting rod 30. The sliding rod 28 is a rod-shaped structure extending along a first direction X. The first mounting structure in the first sensing unit 51 is fixedly connected to the sliding rod 28, and the second mounting structure in the second sensing unit 52 is slidably mounted on the sliding rod 28 along the first direction X.

[0116] The drive block 29 is located between the first mounting structure and the second mounting structure. The drive structure 35 is connected to the drive block 29 and is used to drive the drive block 29 to move along the second direction Y.

[0117] One end of the first connecting rod 31 is rotatably connected to the first mounting structure via a pivot in a third direction Z, and the other end is rotatably connected to the drive block 29 via a pivot in a third direction Z. One end of the second connecting rod 30 is rotatably connected to the second mounting structure via a pivot in a third direction Z, and the other end is rotatably connected to the drive block 29 via a pivot in a third direction Z.

[0118] The working principle of the connecting bracket 8 with the above design is as follows: the driving structure 35 drives the driving block 29 to move along the second direction Y. During the movement of the driving block 29 along the second direction Y, it can drive the ends of the first connecting rod 31 and the second connecting rod 30 connected to the driving block 29 to move in the second direction Y, thereby driving the first mounting structure and the second mounting structure to move relative to each other in the first direction X, thereby achieving the purpose of changing the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X.

[0119] In some embodiments, such as Figure 9As shown, the connecting bracket 8 can be equipped with two sliding rods 28, namely a first sliding rod and a second sliding rod. Both the first and second sliding rods extend along a first direction X and are spaced apart along a second direction Y. A first mounting structure is fixedly connected to both the first and second sliding rods, while a second mounting structure is slidably mounted on both the first and second sliding rods along the first direction X. Alternatively, the first mounting structure is fixedly connected to the first sliding rod and slidably mounted on the second sliding rod along the first direction X, and the second mounting structure is fixedly connected to the second sliding rod and slidably mounted on the first sliding rod along the first direction X. By using two sliding rods 28, the reliability and stability of the first sensing unit 51 and the second sensing unit 52 during the spacing adjustment process can be improved.

[0120] In some embodiments, such as Figure 9 As shown, the drive structure 35 includes a mounting block 33 and a drive rod 32, with the mounting block 33 and drive block 29 spaced apart in the second direction Y. The drive rod 32 extends along the second direction Y, rotatably passes through the mounting block 33 about the second direction Y, and is threadedly engaged with the drive block 29. During the rotation of the drive rod 32 relative to the mounting block 33 about the second direction Y, it drives the drive block 29 to move along the second direction Y. The rotation of the drive rod 32 about its axis can be manually driven or electrically driven.

[0121] For example, the drive rod 32 includes a rotation operation part 34 in the portion relative to the mounting block 33 away from the drive block 29. This knob operation part can be, for example, a knob structure provided on the drive rod 32, a rubber sleeve fitted on the drive rod 32, or a knurled structure embossed on the drive rod 32, etc. The user can rotate the drive rod 32 through the rotation operation part 34 to adjust the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X.

[0122] In another example, the drive structure 35 also includes a drive motor connected to the drive rod 32, which drives the drive rod 32 to rotate relative to the mounting block 33 about the second direction Y, thereby achieving the purpose of electrically adjusting the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X.

[0123] In some embodiments, such as Figure 9 As shown, the connecting bracket 8 also includes a third connecting rod 36 and a fourth connecting rod 37. One end of the third connecting rod 36 is rotatably connected to the first mounting structure via a pivot in a third direction Z, and the other end is rotatably connected to the mounting block 33 via a pivot in a third direction Z. One end of the fourth connecting rod 37 is rotatably connected to the second mounting structure via a pivot in a third direction Z, and the other end is rotatably connected to the mounting block 33 via a pivot in a third direction Z.

[0124] The first connecting rod 31 and the third connecting rod 36 can be designed symmetrically with respect to the reference line, and the second connecting rod 30 and the fourth connecting rod 37 can be designed symmetrically with respect to the reference line; here the reference line is parallel to the first direction X and is located at the center of the drive block 29 and the mounting block 33 in the second direction Y.

[0125] By setting the third connecting rod 36 and the fourth connecting rod 37, the connecting bracket 8 can further improve the reliability and stability of the first sensing unit 51 and the second sensing unit 52 during the spacing adjustment movement.

[0126] In the measuring device 1 provided in the above embodiment, the connecting bracket 8, by adopting an adjustable design, can match the spacing difference between two identical measuring points for different users, and can also match the spacing difference between two different test points for the same user; thus, it can meet different detection requirements and be applicable to different application scenarios.

[0127] The adjustable range of the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X (hereinafter referred to as the adjustable distance range) of the connecting bracket 8 can be specifically designed according to the actual application scenario.

[0128] For example, in the application scenario of measuring pulse wave velocity on the radial artery, and using any two of the three parts of the radial artery, namely the cun, guan, and chi parts, as two measurement points, the adjustable range of the spacing of the connecting stent 8 can be 6mm to 25mm. With the above-mentioned adjustable range of spacing, it can meet the needs of different users using the cun and guan parts as two test points, as well as using the guan and chi parts as two test points.

[0129] The adjustable spacing of the connecting bracket 8 can also be designed to be from 6mm to 35mm. With the above adjustable spacing range, it can meet the needs of different users, using the inch and the gate as two test points, the gate and the ruler as two test points, and the inch and the ruler as two test points.

[0130] like Figure 10 As shown, the measuring device 1 provided in this embodiment of the application further includes a vibration damping structure 38, which is made of a buffer material such as a porous material. The vibration damping structure 38 is disposed on the connecting bracket 8 and located between the first sensing unit 51 and the second sensing unit 52, and is used to improve the influence of external vibration on the first sensing unit 51 and the second sensing unit 52, so as to ensure the accuracy and reliability of the detection results.

[0131] The vibration damping structure 38 can also be partially set on the back side of the mounting structure 9 away from the slot opening 15 to further improve the vibration damping performance of the detection module 4.

[0132] The measuring device 1 provided in this embodiment further includes a restraint structure connected to the connecting bracket 8 for fixing the detection module 4 to the user's body. When the detection module 4 is fixed at a target position on the user's body, the first sensing unit 51 and the second sensing unit 52 can perform pulse wave detection at the two target measurement points. The restraint structure can be, for example, a strap, a wristband, or a buckle.

[0133] The vibration damping structure 38 can also be set between the restraint structure and the connecting bracket 8, thereby avoiding the problem that external vibrations are transmitted to the detection module 4 through the restraint structure, affecting the detection results of the first sensing unit 51 and the second sensing unit 52.

[0134] This application embodiment also provides another adjustable connecting bracket 8, which includes a sliding rod 28 and a driving rod 32, both extending along a first direction X. A first mounting structure is fixedly connected to the sliding rod 28, and a second mounting structure is slidably disposed on the sliding rod 28 along the first direction X. The driving rod 32 is rotatably disposed on the first mounting structure about the first direction X and threadedly engaged with the second mounting structure. During the rotation of the driving rod 32 relative to the first mounting structure about the first direction X, the threaded engagement causes the second mounting structure to slide along the sliding rod 28 along the first direction X, thereby changing the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X.

[0135] The rotation of the drive rod 32 around the axis can be driven manually or electrically. The specific implementation method can be referred to the description above, and will not be repeated here.

[0136] Although the above embodiments provide several adjustable design examples of the connecting bracket 8, the measuring device 1 provided in this application embodiment is not limited to these. Any connecting bracket 8 that can install the first sensing unit 51 and the second sensing unit 52 and can adjust the distance between the first sensing unit 51 and the second sensing unit 52 in the first direction X is acceptable.

[0137] In the measuring device 1 provided in the embodiments of this application, such as Figure 11 As shown, the connecting bracket 8 can also be a fixed bracket. Here, a fixed bracket means that the distance between the two sensing units 5 on the connecting bracket 8 in the first direction X is fixed. Based on different application scenarios, the fixed distance can be designed differently.

[0138] For example, in the application scenario of measuring pulse wave velocity on the radial artery, and taking any two of the three parts of the radial artery, namely the cun, guan and chi parts, as two measurement points, the spacing between the first sensing unit 51 and the second sensing unit 52 on the connecting stent 8 in the first direction X can be designed with reference to the description above.

[0139] In some embodiments, the distance between the first sensing unit 51 and the second sensing unit 52 mounted on the connecting bracket 8 in the first direction X is approximately 11 mm, such as 10 mm, 11 mm, or 12 mm. This design can accommodate applications using either the cun and guan points on the radial artery as two measurement points, or the guan and chi points on the radial artery as two measurement points. In practical use, the user can select the two measurement points with stronger pulses, either cun-guan or guan-chi, based on their specific needs, thereby facilitating the acquisition of pulse wave signals with higher signal-to-noise ratios.

[0140] In some embodiments, the first mounting structure, the second mounting structure, and the connecting bracket 8 are integrated into one structure. This design facilitates the connection and fixation of the first sensing unit 51, the second sensing unit 52, and the connecting bracket 8, and also helps to ensure the accuracy of the spacing between the first sensing unit 51 and the second sensing unit 52 in the first direction X.

[0141] like Figure 12 As shown, the measuring device 1 provided in this application embodiment also includes a vibration damping structure 38. The vibration damping structure 38 is disposed on the connecting bracket 8 and located between the first sensing unit 51 and the second sensing unit 52, and is used to improve the influence of external vibration on the first sensing unit 51 and the second sensing unit 52, so as to ensure the accuracy and reliability of the detection results.

[0142] The vibration damping structure 38 can also be partially set on the back side of the mounting structure 9 and the connecting bracket 8 away from the slot opening 15 to further improve the vibration damping performance of the detection module 4.

[0143] The measuring device 1 provided in this application embodiment also includes a restraint structure. The description of the restraint structure can be found above and will not be repeated here.

[0144] In the measuring device 1 provided in this application embodiment, the processing device 7 is used to acquire the detection results of the light power of the two photodetectors 6. Based on the detection results, two pulse wave signals that pass through the two measurement points successively can be obtained. Then, the time interval between the two pulse wave signals is determined by the data processing method. Finally, the pulse wave velocity is calculated based on the distance between the two sensing units 5.

[0145] Because the pulse wave is affected by the reflected wave of the previous pulse wave, the peak position will shift. Therefore, using the peak as the time reference point will lead to a large error in the measurement of pulse wave velocity. Furthermore, since the rising edge of the pulse wave is less affected by the previous pulse wave, in the measurement device 1 provided in this application embodiment, the processing device 7 uses the intersecting tangent method to process the two pulse wave signals, and uses the intersection tangent point (the intersection of the tangent line at the maximum value of the first difference of the rising edge of the pulse wave and the tangent line at the trough) as the time reference point to calculate the time interval between the two pulse wave signals.

[0146] Specifically, the processing procedure of the processing device 7 for the two acquired pulse wave signals is illustrated below:

[0147] First, low-pass filtering is used to remove high-frequency noise, then wavelet denoising is used to remove baseline drift, and finally normalization is performed.

[0148] like Figure 13 As shown, the first-order difference extrema and troughs of the rising edge of the normalized pulse wave signal are extracted, and the tangents at the first-order difference extrema and troughs are plotted; the intersection of the two tangents is taken as the time reference point.

[0149] After extracting the time reference points of the two pulse wave signals, the pulse wave velocity is calculated based on the time interval between the time reference points and the pre-measured distance between the two sensing units 5.

[0150] By processing the two pulse wave signals using the intersecting tangent method, the influence of reflected waves can be eliminated, resulting in a more accurate time interval, which is beneficial for obtaining accurate pulse wave velocity. Simultaneously, it is applicable when the distance between the two measurement points is small, which is conducive to the miniaturization of the measuring device 1.

[0151] It should be noted that, although Figure 1 The structure of the measuring device 1 is shown in the form of discrete components, but some or all of the laser source 2, beam splitter 3, photodetector 6 and processing device 7 in the measuring device 1 can be integrated into the detection module 4 to improve the integration of the measuring device 1, which is beneficial to the miniaturization and integration of the measuring device 1.

[0152] The measuring device 1 provided in this application embodiment can be a medical testing device or integrated into a medical testing device. The measuring device 1 can enrich the acquisition of cardiovascular function parameters.

[0153] The measuring device 1 provided in this application embodiment can be a smart wearable device and a home medical monitoring device for daily cardiovascular health monitoring and personal health management. Smart wearable devices can be, for example, smartwatches or smart bracelets used for measuring pulse wave velocity in the radial artery.

[0154] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A device for measuring pulse wave velocity, characterized in that, The measuring device includes a connecting bracket and two sensing units spaced apart on the connecting bracket along a first direction. The sensing units include a mounting structure, a cascaded fiber optic structure, and an elastic structure. The mounting structure is provided with a mounting groove, and the mounting groove has a groove opening on the third-facing side; The cascaded fiber structure includes a first single-mode fiber, a multimode fiber, and a second single-mode fiber connected in sequence. The cascaded fiber structure passes through the mounting slot along a second direction, and the multimode fiber is located in the mounting slot. The elastic structure includes a filled portion and an exposed portion. The filled portion fills the mounting groove and wraps the multimode optical fiber. The filled portion and the exposed portion are connected at the opening of the groove, and the exposed portion is located outside the mounting groove. Wherein, the first direction, the second direction, and the third direction are mutually perpendicular to each other.

2. The measuring device according to claim 1, characterized in that, The two sensing units are a first sensing unit and a second sensing unit, respectively, and the connecting bracket is an adjustable bracket structure that can adjust the distance between the first sensing unit and the second sensing unit in the first direction.

3. The measuring device according to claim 2, characterized in that, The connecting bracket includes a sliding rod, a driving block, a driving structure, a first transmission rod, and a second transmission rod; The sliding rod extends along the first direction, the first sensing unit is fixedly connected to the sliding rod, and the second sensing unit is slidably disposed on the sliding rod; The driving block is located between the first sensing unit and the second sensing unit, and the driving structure is connected to the driving block for driving the driving block to move along the second direction; One end of the first transmission rod is rotatably connected to the first sensing unit about the third direction, and the other end is rotatably connected to the drive block about the third direction. One end of the second transmission rod is rotatably connected to the second sensing unit about the third direction, and the other end is rotatably connected to the drive block about the third direction.

4. The measuring device according to claim 3, characterized in that, The drive structure includes a mounting block and a drive rod, wherein the mounting block and the drive block are spaced apart in the second direction; The drive rod extends along the second direction, is rotatably mounted on the mounting block about the second direction, and is threadedly engaged with the drive block.

5. The measuring device according to claim 4, characterized in that, The connecting bracket also includes a third transmission rod and a fourth transmission rod; One end of the third transmission rod is rotatably connected to the first sensing unit about the third direction, and the other end is rotatably connected to the mounting block about the third direction. One end of the fourth transmission rod is rotatably connected to the second sensing unit about the third direction, and the other end is rotatably connected to the mounting block about the third direction.

6. The measuring device according to claim 4 or 5, characterized in that, The drive rod includes a rotation operating part in the portion of the drive block that is away from the mounting block; Alternatively, the drive structure may further include a drive motor connected to the drive rod, which drives the drive rod to rotate relative to the mounting block about the second direction.

7. The measuring device according to claim 2, characterized in that, The connecting bracket includes a sliding rod and a driving rod, both of which extend along the first direction; The first sensing unit is fixedly connected to the sliding rod, and the second sensing unit is slidably disposed on the sliding rod; The drive rod is rotatably mounted on the first sensing unit around the first direction and is threadedly engaged with the second sensing unit.

8. The measuring device according to claim 7, characterized in that, The drive rod includes a rotation operation part in the portion that is farther away from the second sensing unit relative to the first sensing unit; Alternatively, the connecting bracket may further include a drive motor connected to the drive rod, which is used to drive the drive rod to rotate relative to the first sensing unit around the first direction.

9. The measuring device according to any one of claims 2 to 8, characterized in that, Under the action of the connecting bracket, the distance between the first sensing unit and the second sensing unit in the first direction is adjustable from 6mm to 35mm.

10. The measuring device according to claim 1, characterized in that, The connecting bracket is a fixed bracket structure, and the distance between the two sensing units in the first direction is fixed.

11. The measuring device according to claim 10, characterized in that, The distance between the two sensing units in the first direction is 6 mm to 35 mm.

12. The measuring device according to any one of claims 1 to 11, characterized in that, The material of the elastic structure includes polydimethylsiloxane or silicone.

13. The measuring device according to any one of claims 1 to 12, characterized in that, The exposed portion has a sensing contact surface that protrudes outward relative to the slot opening, and the sensing contact surface includes a smoothly transitioned arcuate surface.

14. The measuring device according to any one of claims 1 to 13, characterized in that, The sensing unit further includes a sensitivity-enhancing structure, which is disposed on the bottom surface of the mounting groove opposite to the groove opening, and includes a plurality of sensitivity-enhancing protrusions spaced apart in the second direction.

15. The measuring device according to claim 14, characterized in that, The cross-sectional shape of the sensitivity-enhancing protrusion in the reference plane is triangular, quadrilateral, pentagonal, or hexagonal; The reference plane is parallel to the first direction and the third direction.

16. The measuring device according to any one of claims 1 to 15, characterized in that, The measuring device also includes a vibration damping structure made of a cushioning material, which is mounted on the connecting bracket and located between the two sensing units.

17. The measuring device according to any one of claims 1 to 16, characterized in that, The measuring device also includes a restraint structure and a vibration damping structure. The restraint structure is connected to the connecting bracket and is used to fix the connecting bracket to the human body. The vibration damping structure is made of a cushioning material and is disposed between the restraint structure and the connecting bracket.

18. The measuring device according to any one of claims 1 to 17, characterized in that, In the mounting slot, the multimode optical fiber extends 5 mm to 15 mm along the second direction.

19. The measuring device according to any one of claims 1 to 18, characterized in that, The measuring device is used to measure pulse wave velocity on a single artery, and the two sensing units are used to detect pulse waves at two measurement points on the single artery; the single artery is the radial artery, carotid artery, or femoral artery.

20. The measuring device according to any one of claims 1 to 19, characterized in that, The measuring device is used to measure pulse wave velocity on the radial artery, and any two of the cun, guan and chi portions of the radial artery are used as two measurement points of the two sensing units.

21. The measuring device according to any one of claims 1 to 20, characterized in that, The measuring device also includes a laser source, a beam splitter, two photodetectors, and a processing device; The laser source is used to generate an optical signal that is output to the beam splitter; The beam splitter is used to split the optical signal and input it into the cascaded fiber structure in the two sensing units; The two photodetectors are used to detect the optical signals output from the two cascaded fiber structures, respectively. The processing device is configured to calculate the pulse wave velocity based on the detection results of the two photodetectors.

22. The measuring device according to any one of claims 1 to 21, characterized in that, The measuring device is a smart wearable device.

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