A vital sign monitoring device with a layered structure

Abstract

The present invention proposes a vital sign monitoring device with a layered structure. By arranging a soft buffer layer and a hard support layer, a unified use environment is provided. The monitoring consistency of breathing or heartbeat is better under the influence of different mattress use environments, people of different weights, different lying postures, and different sensing parts. Experiments have proved that the device can effectively restore breathing and heart rate signals. The buffer layer ensures that the sensing optical fiber has sufficient space for deformation, ensuring that the sensing optical fiber accurately restores the vibration signal. The support layer supports the above layers, and at the same time, ensures that the hardness or softness of the lower layer material will not affect the restoration of the vibration signal by the sensing optical fiber, ensuring the consistency of the present invention in different use environments, creating a unified use environment, and adapting to different use scenarios. The mattress made by the present invention can be placed under a 0-50mm ordinary commercial mattress, and no matter what material is under the mattress, breathing and heart rate signals can be accurately monitored.

Description

Technical Field

[0001] The invention relates to the field of human vital signs monitoring, and in particular to a vital signs monitoring device with a layered structure. Background Art

[0002] With the development of social economy and technology and the improvement of people's quality of life, people's demand for health testing is increasing. Respiratory rate and heart rate are the most basic vital signs of the human body. The pathological signs of the human body are often reflected in abnormal respiratory rate and heart rate. Therefore, daily real-time monitoring of respiratory rate and heart rate is of great significance to human health assessment and disease prevention. Long-term respiratory rate and heart rate monitoring can enable the health status of the monitored person to be monitored in real time, but most traditional monitoring systems use contact wearable devices, which have poor user experience. Not only does the monitoring interfere with the life of the monitored person, but the accuracy of the monitoring effect is also limited.

[0003] In recent years, non-contact monitoring systems have developed rapidly. Sensing systems based on the principle of optical fiber sensing have the characteristics of high sensitivity, good comfort, and resistance to electromagnetic interference. However, the current monitoring device based on fiber grating sensors has a complex system structure and manufacturing process, and the acquired signal needs to be wavelength demodulated, resulting in high system costs and complex demodulation methods. Monitoring systems based on the principle of interference either need to undergo phase demodulation, resulting in complex demodulation methods and high system costs, or the interference signal is easily affected by the environment, polarization, and phase fading, and cannot accurately extract complete breathing and heartbeat signals.

[0004] The detection system based on the principle of optical fiber bending loss can reduce the influence of optical phase fading and polarization, and monitor vital signs such as breathing and heartbeat signals more accurately. In the actual monitoring process, it was found that different mattress usage environments, people of different weights, different lying positions, different sensing parts and other factors will have relatively large differences in the use effect of the mattress, ultimately affecting the accuracy of the monitoring results. Summary of the invention

[0005] In view of this, the present invention proposes a vital signs monitoring device with a layered structure, which can provide a unified usage environment and achieve better consistency in monitoring breathing or heartbeat under the influence of different mattress usage environments, people of different weights, different lying postures, and different sensing locations.

[0006] The technical solution of the present invention is implemented as follows: The present invention provides a vital sign monitoring device with a layered structure, comprising an optical fiber sensing component (1), the optical fiber sensing component (1) comprising a vibration sensitive film (11) and a sensing optical fiber (12), the sensing optical fiber (12) being coiled and attached to the surface of the vibration sensitive film (11), the sensing optical fiber (12) being bent after being subjected to external pressure, and the optical signal transmitted in the sensing optical fiber (12) being lost and modulated at the bending portion, and further comprising a buffer layer (13) and a support layer (14), the vibration sensitive film (11), the sensing optical fiber (12), the buffer layer (13) and the support layer (14) being stacked in sequence, the buffer layer (13) having a 25% indentation hardness of 35 to 80N, and the support layer (14) having a Rockwell hardness of 48 to 60 degrees.

[0007] On the basis of the above technical solution, preferably, the buffer layer (13) is made of sponge with a porosity of 75% to 90% and a thickness of 5 to 25 mm.

[0008] On the basis of the above technical solution, preferably, the support layer (14) is made of a PP plastic plate with a thickness of 1 to 3 mm.

[0009] On the basis of the above technical solution, preferably, the optical fiber sensing component (1) further comprises a sensitivity enhancement wire (15), wherein the sensitivity enhancement wire (15) is attached to the surface of the vibration sensitive film (11) and is in point contact with the sensing optical fiber (12).

[0010] Further preferably, the sensitivity enhancement wire (15) is made of nylon material, steel wire or optical fiber, with a diameter of 0.8 to 2 mm, and the core diameter of the sensing optical fiber (12) is less than or equal to 5 μm.

[0011] Further preferably, the optical fiber sensing assembly (1) further comprises a packaging sleeve (16), and the vibration sensitive film (11), the sensing optical fiber (12), the buffer layer (13) and the supporting layer (14) are stacked and placed inside the packaging sleeve (16).

[0012] More preferably, the packaging sleeve (16) is made of rainproof cloth, ecological leather or Oxford cloth with a thickness of 0.8 to 2 mm.

[0013] On the basis of the above technical solution, preferably, the vibration sensitive film (11) is made of polyethylene film with a thickness of 0.1 to 0.3 mm.

[0014] On the basis of the above technical solution, preferably, it further comprises a laser light source (2), a photoelectric conversion module (3) and a vital sign signal extraction and analysis module (4), wherein:

[0015] A laser light source (2) emits laser light to a sensing optical fiber (12);

[0016] The sensing optical fiber (12) is connected to the laser light source (2) and the photoelectric conversion module (3) respectively;

[0017] The photoelectric conversion module (3) is connected to the vital sign signal extraction and analysis module (4) to convert the optical signal into an electrical signal;

[0018] The vital sign signal extraction and analysis module (4) extracts vital sign information from the electrical signal.

[0019] On the basis of the above technical solution, preferably, the optical fiber sensing component (1) is placed on the surface or inside of a seat cushion, a mattress, an insole or a pillow.

[0020] The layered vital sign monitoring device of the present invention has the following beneficial effects compared with the prior art:

[0021] (1) By setting a soft cushioning layer and a hard supporting layer, a uniform use environment is provided, and the monitoring consistency of breathing or heartbeat is better under the influence of different mattress use environments, people of different weights, different lying postures, and different sensor locations. Experiments have shown that it can effectively restore breathing and heart rate signals;

[0022] (2) The buffer layer ensures that the sensing optical fiber has sufficient space for deformation, thereby ensuring that the sensing optical fiber accurately restores the vibration signal;

[0023] (3) The support layer supports the above layers, and at the same time, ensures that the hardness or softness of the material of the lower layer does not affect the restoration of the vibration signal by the sensing optical fiber, thereby ensuring the consistency of the present invention in different use environments, creating a unified use environment, and adapting to different use scenarios. The mattress made by the present invention can be placed under a 0-50mm ordinary commercial mattress, and no matter what material is under the mattress, the breathing and heart rate signals can be accurately monitored;

[0024] (4) The vital signs monitoring device of the present invention has the advantages of simple structure, easy implementation, low manufacturing cost, reliable operation, high sensitivity, real-time detection, and easy signal demodulation. It can be built into daily necessities such as seat cushions, mattresses, insoles or pillows, so that users can monitor their physical condition in real time in their daily work and life, and can promptly notify family members and medical staff in an emergency to avoid accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 It is a schematic diagram of the connection relationship of the vital signs monitoring device of the present invention;

[0027] Figure 2 It is a front cross-sectional schematic diagram of the optical fiber sensing component part of the vital signs monitoring device of the present invention;

[0028] Figure 3 A top view of the vibration sensitive film, sensing optical fiber and sensitivity enhancement line of the vital signs monitoring device of the present invention;

[0029] Figure 4 The breathing and heartbeat monitoring graphs of Examples 1 and 2 of the present invention. DETAILED DESCRIPTION

[0030] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] like Figure 1 As shown, the layered structure of the vital sign monitoring device of the present invention includes an optical fiber sensing component 1, a laser light source 2, a photoelectric conversion module 3, and a vital sign signal extraction and analysis module 4.

[0032] Among them, Figure 2 As shown, the optical fiber sensing assembly 1 includes a vibration sensitive film 11, a sensing optical fiber 12, a buffer layer 13, a supporting layer 14, a sensitivity enhancement line 15 and a packaging sleeve 16.

[0033] The vibration sensitive film 11 can not only transmit the vibration to the sensing optical fiber 12 without loss, but also protect the sensing optical fiber 12 from being easily broken. Specifically, a polyethylene film with a thickness of 0.1 to 0.3 mm can be used.

[0034] The sensing optical fiber 12 bends after being subjected to external pressure. Based on the bending loss principle, the optical signal transmitted in the sensing optical fiber 12 is lost at the bending portion and modulated. The principle of optical signal modulation using the bending loss principle is as follows:

[0035] When the light energy transmitted in the core of the optical fiber propagates in a straight optical fiber, due to the different refractive indices of the core and the cladding, total reflection is formed in the core, and the energy loss in the optical fiber is extremely small. However, when the optical fiber is bent, the refractive index inside the optical fiber becomes uneven, destroying the conditions for total reflection. Part of the light energy is very likely to leak from the cladding and cause energy loss. By monitoring the energy loss of light during transmission, the degree of optical fiber bending can be calculated.

[0036] Based on the above principles, the inventors have found through repeated experiments that the core diameter of an ordinary single-mode optical fiber is 9μm. During the bending process, only a small part of the optical power in the optical fiber leaks, and the dynamic response of the optical power is not obvious, which makes it difficult to directly apply to the detection of small signals such as breathing and heart rate. However, due to the narrower path for light passing through a smaller core diameter, for the same length of optical fiber, the total reflection points of the light beam propagating in the small core diameter optical fiber increase significantly, which means that after the force is bent, the number of points where the light leaks into the cladding increases. At the same time, the compression and stretching of the bending have a greater impact on the uneven refraction of the optical fiber, which is more likely to destroy the conditions of total reflection, and the optical power loss is greater, that is, the dynamic response amplitude of the optical power to bending is larger, which can be fully applied to small signal detection.

[0037] Based on the above findings, the core diameter of the sensing optical fiber 12 used in the present invention is less than or equal to 5μm. By setting a small core diameter optical fiber, the small core diameter optical fiber is more sensitive to the change in optical power caused by bending loss, which is beneficial to small signal detection. The tiny vibration caused by the squeezing caused by breathing and heartbeat causes the bending change of the optical fiber. In the small core diameter optical fiber that is more sensitive to bending loss, the optical signal will be significantly modulated in intensity. The optical power that changes with the correlation between breathing and heartbeat is output at the output end of the sensing optical fiber, which has higher sensitivity and better accuracy. Specifically, Figure 3 As shown, the sensing optical fiber 12 is coiled and adhered to the surface of the vibration sensitive film 11, and the sensing optical fiber 12 is bent in an "S" shape.

[0038] The sensitivity enhancement wire 15 is attached to the surface of the vibration sensitive film 11 and is in point contact with the sensing optical fiber 12. Its function is to convert the vibration signal of the overall plane into a vibration signal of a local point, so as to increase the sensitivity of the bending loss of the sensing optical fiber 12, transmit the maximum amplitude of the vibration to the sensing optical fiber 12, and improve the sensitivity of the bending of the sensing optical fiber 12 caused by weak vibrations such as breathing and heartbeat. Specifically, the sensitivity enhancement wire 15 is made of nylon material, steel wire or plastic optical fiber, and has a diameter of 0.8 to 2 mm. Specifically, the sensitivity enhancement wire 15 is attached to the surface of the vibration sensitive film 11.

[0039] The buffer layer 13 ensures that the sensing optical fiber has enough space for deformation and ensures that the sensing optical fiber accurately restores the vibration signal. The buffer layer 13 should not be too soft or too hard. If it is too hard, the vibration conduction effect is not good, the optical fiber is broken, and the light flux is very low; if it is too soft, it will cause the sensing optical fiber 12 and the buffer layer 13 to move as a whole, and the conduction effect is not good. Preferably, the 25% depression hardness of the buffer layer 13 of the present invention is 35-80N. Specifically, the buffer layer 13 adopts a foam material with a 25% depression hardness of 35-80N and a thickness of 5-25mm. More specifically, the buffer layer 13 adopts a sponge with a porosity of 75%-90% and a thickness of 5-25mm.

[0040] The support layer 14 supports the above layers and ensures that the hardness of the lower layer material will not affect the restoration of the vibration signal by the sensing optical fiber, thereby ensuring the consistency of the present invention in different usage environments, creating a unified usage environment, and adapting to different usage scenarios. Preferably, the Rockwell hardness of the support layer 14 of the present invention is 48 to 60 degrees. The support layer 14 is made of a hard board, and the material includes but is not limited to plastic, wood, paper and metal. Specifically, the support layer 14 is made of a PP plastic board with a thickness of 1 to 3 mm.

[0041] Specifically, the vibration sensitive film 11, the sensing optical fiber 12, the buffer layer 13 and the support layer 14 are stacked in sequence, the buffer layer 13 and the vibration sensitive film 11 are bonded to each other, and the buffer layer 13 and the support layer 14 are bonded to each other, and UV glue can be used for bonding.

[0042] The packaging sleeve 16 is used to package and fix the vibration sensitive film 11, the sensing optical fiber 12, the buffer layer 13 and the support layer 14. Specifically, the vibration sensitive film 11, the sensing optical fiber 12, the buffer layer 13 and the support layer 14 are stacked and placed in the packaging sleeve 16. Specifically, the packaging sleeve 16 is made of rainproof cloth, ecological leather or Oxford cloth with a thickness of 0.8 to 2 mm. The rainproof cloth, ecological leather or Oxford cloth is light, waterproof and moisture-resistant, and has good softness, and can accurately transmit breathing and heartbeat vibrations to the sensing optical fiber 12.

[0043] The laser light source 2 emits laser light to the sensing optical fiber 12 and can adopt existing technology.

[0044] The sensing optical fiber 12 is connected to the laser light source 2 and the photoelectric conversion module 3 respectively, and the existing technology can be adopted.

[0045] The photoelectric conversion module 3 is connected to the vital sign signal extraction and analysis module 4 to convert the optical signal into an electrical signal, and the existing technology can be used.

[0046] The vital sign signal extraction and analysis module 4 extracts vital sign information from the electrical signal and can adopt existing technology.

[0047] Example 1

[0048] The vital sign monitoring device of this embodiment includes an optical fiber sensing component 1, a laser light source 2, a photoelectric conversion module 3, and a vital sign signal extraction and analysis module 4. The optical fiber sensing component 1 includes a vibration sensitive film 11, a sensing optical fiber 12, a sensitivity enhancement line 15, and a packaging sleeve 16.

[0049] The vibration sensitive film 11 is made of polyethylene film with a thickness of 0.2 mm;

[0050] The sensing optical fiber 12 is bent in an "S" shape and has a diameter of 5 μm;

[0051] The sensitivity enhancement line 15 is made of plastic optical fiber with a diameter of 1 mm, and the sensing optical fiber 12 with an "S"-shaped curved line is pressed against the surface of the vibration sensitive film 11;

[0052] The packaging sleeve 16 is made of ecological leather with a thickness of 1.2 mm.

[0053] The vibration sensitive film 11 and the sensing optical fiber 12 are packaged in a packaging sleeve 16 and built into a mattress, placed under a 30 mm thick commercial mattress, and the breathing and heartbeat signals are monitored in different use environments to obtain Figure 4 Spectrum shown.

[0054] Example 2

[0055] The vital sign monitoring device of this embodiment includes an optical fiber sensing component 1, a laser light source 2, a photoelectric conversion module 3, and a vital sign signal extraction and analysis module 4. The optical fiber sensing component 1 includes a vibration sensitive film 11, a sensing optical fiber 12, a buffer layer 13, a support layer 14, a sensitivity enhancement line 15, and a packaging sleeve 16.

[0056] The vibration sensitive film 11 is made of polyethylene film with a thickness of 0.2 mm;

[0057] The sensing optical fiber 12 is bent in an "S" shape and has a diameter of 5 μm;

[0058] The sensitivity enhancement line 15 is made of plastic optical fiber with a diameter of 1 mm, and the sensing optical fiber 12 with an "S"-shaped curved line is pressed against the surface of the vibration sensitive film 11;

[0059] The buffer layer 13 is made of sponge with a porosity of 80% and a thickness of 15 mm;

[0060] The supporting layer 14 is made of a PP plastic plate with a thickness of 1.3 mm;

[0061] The packaging sleeve 16 is made of ecological leather with a thickness of 1.2 mm.

[0062] The vibration sensitive film 11 and the sensing optical fiber 12 are packaged in a packaging sleeve 16 and built into a mattress, placed under a 30 mm thick commercial mattress, and the breathing and heartbeat signals are monitored in different use environments to obtain Figure 4 Spectrum shown.

[0063] Depend on Figure 4 It can be seen that:

[0064] In Example 1, since the hard bed board is too hard compared to the soft bed board, when a heavier person lies on it, the optical power in the sensing optical fiber drops sharply, the output signal is weak, the amplitude of the breathing and heartbeat signals is too small, and the noise increases significantly, which is not conducive to the subsequent signal detection and processing.

[0065] In Example 2, both the hard bed board and the soft bed board can effectively restore the breathing and heart rate signals.

[0066] In summary, the vital signs monitoring device of Example 2 can be applied to different scenarios, has a wider range of uses, and is easy for commercial and civilian use.

[0067] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A vital sign monitoring device with a layered structure, comprising an optical fiber sensing component (1), the optical fiber sensing component (1) comprising a vibration sensitive film (11) and a sensing optical fiber (12), the sensing optical fiber (12) being coiled and attached to the surface of the vibration sensitive film (11), the sensing optical fiber (12) being bent after being subjected to external pressure, and the optical signal transmitted in the sensing optical fiber (12) being lost at the bent portion and being modulated, characterized in that: It also includes a buffer layer (13) and a support layer (14), wherein the vibration sensitive film (11), the sensing optical fiber (12), the buffer layer (13) and the support layer (14) are stacked in sequence, the 25% indentation hardness of the buffer layer (13) is 35 to 80N, and the Rockwell hardness of the support layer (14) is 48 to 60 degrees.

2. The hierarchical vital sign monitoring device according to claim 1, characterized in that: The buffer layer (13) is made of sponge with a porosity of 75% to 90% and a thickness of 5 to 25 mm.

3. The hierarchical vital sign monitoring device according to claim 1, characterized in that: The support layer (14) is made of a PP plastic plate with a thickness of 1 to 3 mm.

4. The hierarchical vital sign monitoring device according to claim 1, characterized in that: The optical fiber sensing component (1) also includes a sensitivity enhancement line (15), wherein the sensitivity enhancement line (15) is attached to the surface of the vibration sensitive film (11) and is in point contact with the sensing optical fiber (12).

5. The hierarchical vital sign monitoring device according to claim 4, characterized in that: The sensitivity enhancement line (15) is made of nylon material, steel wire or optical fiber, and has a diameter of 0.8 to 2 mm. The core diameter of the sensing optical fiber (12) is less than or equal to 5 μm.

6. The hierarchical vital sign monitoring device according to claim 4, characterized in that: The optical fiber sensing component (1) also includes a packaging sleeve (16), and the vibration sensitive film (11), the sensing optical fiber (12), the buffer layer (13) and the supporting layer (14) are stacked and placed in the packaging sleeve (16).

7. The hierarchical vital sign monitoring device according to claim 6, characterized in that: The packaging sleeve (16) is made of rainproof cloth, ecological leather or Oxford cloth with a thickness of 0.8 to 2 mm.

8. The hierarchical vital sign monitoring device according to claim 1, characterized in that: The vibration sensitive film (11) is made of polyethylene film with a thickness of 0.1-0.3 mm.

9. The layered vital sign monitoring device according to claim 1, characterized in that: It also includes a laser light source (2), a photoelectric conversion module (3) and a vital sign signal extraction and analysis module (4), wherein: A laser light source (2) emits laser light to a sensing optical fiber (12); The sensing optical fiber (12) is connected to the laser light source (2) and the photoelectric conversion module (3) respectively; The photoelectric conversion module (3) is connected to the vital sign signal extraction and analysis module (4) to convert the optical signal into an electrical signal; The vital sign signal extraction and analysis module (4) extracts vital sign information from the electrical signal.

10. The hierarchical vital sign monitoring device according to claim 1, characterized in that: The optical fiber sensing component (1) is placed on the surface or inside of a seat cushion, a mattress, a shoe insole and a pillow.

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