CN107661096B

CN107661096B - Pulse wave sensor, pulse wave monitoring method and wearing device

Info

Publication number: CN107661096B
Application number: CN201610599137.2A
Authority: CN
Inventors: 陈伟; 张晋; 钟山; 朱中华
Original assignee: Zhigan Shanghai Photon Technology Co ltd
Current assignee: Zhigan Shanghai Photon Technology Co ltd
Priority date: 2016-07-27
Filing date: 2016-07-27
Publication date: 2024-02-06
Anticipated expiration: 2036-07-27
Also published as: CN107661096A

Abstract

The invention provides an optical scanning type pulse wave sensor, a wearable device, an optical scanning type wrist type pulse wave analyzer, an optical scanning type heart rate meter, an optical scanning type blood pressure monitor, an optical scanning type blood vessel hardness tester, an optical scanning type carotid artery hardness tester and a pulse wave monitoring method. The pulse wave sensor comprises a laser emitter for emitting first laser; a branching optical waveguide member that receives the first laser light and branches the first laser light into a second laser light and a reference light; a light guiding output part for receiving and adjusting the second laser to form a third laser, so that the third laser can be incident on the blood vessel; a light guide input part receiving and adjusting the fourth laser light reflected from the blood vessel to form a fifth laser light; and the receiving light path component is used for receiving the fifth laser and the reference light to form sixth laser after double-path interference. The optical scanning pulse wave sensor, the related monitoring equipment and the wearable device provided by the invention can realize continuous monitoring, and have the advantages of high accuracy, good effect and low power consumption.

Description

Pulse wave sensor, pulse wave monitoring method and wearing device

Technical Field

The invention belongs to the technical field of pulse wave monitoring in electronic medical equipment, relates to measurement by adopting an optical device, and particularly relates to a pulse wave sensor, a pulse wave monitoring method and a wearing device.

Background

Cardiovascular disease is the primary disease currently threatening the health of humans, whose pulse waves reflect the functioning of the cardiovascular system. The information such as organism physiology, mental state, physical strength level and the like reflected by the intensity, speed and rhythm of the pulse wave can display the personal health state or be used as auxiliary monitoring of other medical instruments, provide diagnosis references for doctors and the like.

The current pulse wave monitoring method mainly adopts the principle of a photo-electric volume method (PPG) or a piezoelectric sensor to indirectly reflect the change of the pulse wave. The photoplethysmography is a method in which the light intensity of a Light Emitting Diode (LED) irradiated onto the skin is changed by the light absorption effect of hemoglobin in blood, and pulse wave waveforms are indirectly obtained by measuring light reflected from the skin. For example, chinese patent application CN102319075a discloses a blood oxygen saturation measuring apparatus and a measuring method, the measuring apparatus comprising: the microprocessor outputs square waves with different frequencies and in a ratio of 2 times, the square waves drive at least two light emitting diodes, light emitted by the light emitting diodes is received by the photosensitive device after passing through the finger to be measured, the photosensitive device converts the light into a voltage signal, the voltage signal is converted into a preset amplitude voltage signal through the current/voltage conversion amplifier, the analog-to-digital converter converts the preset amplitude voltage signal into a digital signal, and the microprocessor processes the digital signal to obtain the blood oxygen saturation. In another piezoelectric sensing rule, the fluctuation of the skin is caused by the fluctuation of the pulse, and because the interval between the sensor and the skin is very small, when the skin fluctuates, the fluctuation of air between the sensor and the pressure-receiving element is caused, and then the air acts on the piezoelectric film to generate an electric signal, so that the mechanical fluctuation of the pulse is converted into the change of the electric signal. For example, chinese patent application CN105391830a discloses a method of measuring pulse, comprising: after the mobile terminal starts a preset application program, if a piezoelectric sensing area preset by the mobile terminal detects a pulse pressure signal of a human body, the pulse pressure signal is converted into a pulse electric signal.

The problems of inaccurate measurement results and poor repeatability exist in the two methods of adopting a photo-electric volume method (PPG) or piezoelectric induction. In the PPG scheme, the alternating current component (AC) of the measured light intensity curve is directly related to the pulse pressure. And thus can be used to estimate the systolic pressure (SBP)/diastolic pressure (DBP). However, the ac component obtained by PPG measurement is also affected by various factors such as the relative positions of the light emitter/light receiver and the blood vessel, and thus the accuracy and effectiveness of the measurement are reduced. In order to realize reliable monitoring, the PPG method needs to enlarge the irradiation area of the light source LED, and the light detector is also designed to be capable of receiving the reflection of different parts. So that more light energy is actually wasted on ineffective illumination, only a small portion of the reflected light actually carries the information of the pulse in the blood vessel.

In addition, pulse wave monitor equipment in the medical market is relatively large in size, only can carry out single-point or short-time monitoring on pulse during use, data cannot be transmitted wirelessly, interference signals are large, the operation is complex, measurement by professionals is needed, and the result is influenced by subjective factors and is easy to distort. The pulse wave monitor in the home market has the problems of inaccurate measurement results, high power consumption, insufficient standby time and the like, and can not meet the demands of people.

Disclosure of Invention

The invention aims to solve the technical problem of providing a pulse wave sensor, a wrist type pulse wave analyzer, a blood pressure monitor, a pulse wave monitoring method and a wearable device, wherein the pulse wave sensor measures an optical path and a phase difference to accurately and reliably reflect the pulsation of a blood vessel by adopting an optical scanning mode, so as to monitor the cardiovascular system condition.

In order to solve the above technical problems, the present invention provides a pulse wave sensor, comprising:

a laser emitter that emits a first laser light;

a branching optical waveguide member that receives the first laser light and branches the first laser light into a second laser light and a reference light;

a light guide output member that receives and adjusts the second laser light to form a third laser light so that the third laser light can be incident on a blood vessel;

a light guide input part receiving and adjusting the fourth laser light reflected from the blood vessel to form a fifth laser light;

a receiving light path component for receiving the fifth laser and the reference light to form a sixth laser after two-way interference;

and a photodetector for receiving the sixth laser.

According to one embodiment of the invention, the light guiding output means comprises a 1 to M multi-way optical waveguide array or a 1 to N optical waveguide switch, and the light guiding input means comprises a 1 to M multi-way optical waveguide array or a 1 to N optical waveguide switch;

wherein M, N is an integer and greater than 1.

According to one embodiment of the present invention, the 1 to M multiplexing optical waveguide array includes a multi-stage 1 to 2 beam splitting optical path unit, and after implementing 1 to M multiplexing optical splitting, all M transmission optical paths are provided with phase control components to change phases of light beams in the transmission optical paths; the 1 to N optical waveguide switch comprises optical waveguide switch units of multiple stages 1 to 2, and the phase control component is arranged on a double transmission optical path in each optical waveguide switch unit.

According to an embodiment of the present invention, the phase control part includes a metal thin film provided on the transmission optical path, and adjusts the refractive index of the material of the transmission optical path by electrically heating the metal thin film.

According to an embodiment of the present invention, the phase control section includes a liquid crystal layer provided on the transmission optical path and a double electrode provided on the liquid crystal layer, and adjusts a refractive index of the liquid crystal layer by changing a voltage of the double electrode.

According to one embodiment of the invention, the phase control element comprises a polymer layer arranged on the output light path and a double electrode arranged on the polymer layer, the phase control element adjusting the refractive index of the polymer layer by varying the voltage of the double electrode.

According to one embodiment of the present invention, further comprising a first microlens and a second microlens, the third laser light reaching the blood vessel through the first microlens; the fourth laser light passes through the second microlens to reach the light guide input section.

According to one embodiment of the present invention, the first and second microlenses are layered structures comprising multiple silicon oxynitride layers having different refractive indices.

According to one embodiment of the present invention, the first microlenses and the light guiding output members are integrally formed, and the second microlenses and the light guiding input members are integrally formed.

According to one embodiment of the invention, the laser transmitter is a near infrared laser transmitter.

According to one embodiment of the invention, the receiving optical path component comprises a dual optical interferometer.

The invention also provides a wrist type pulse wave analyzer comprising a housing and a belt body connected with the housing, wherein the housing comprises the pulse wave sensor as claimed in any one of claims 1 to 11.

The invention also provides a blood pressure monitor, which comprises a controller and at least two groups of pulse wave sensors, wherein the two groups of pulse wave sensors are separated by a set distance; wherein the controller receives the pulse waves obtained by the two groups of pulse wave sensors to calculate the transmission speed of the pulse waves, and calculates the blood pressure according to the transmission speed.

According to one embodiment of the invention, the two sets of pulse wave sensors can share the same laser transmitter.

The invention also provides a blood vessel hardness tester, which comprises a controller and at least two groups of pulse wave sensors, wherein the two groups of pulse wave sensors are separated by a set distance; wherein the controller receives the pulse waves obtained by the two groups of pulse wave sensors to calculate the conduction velocity of the pulse waves, and calculates the hardness of the blood vessel according to the conduction velocity.

The invention also provides a carotid artery hardness tester, which comprises a controller and at least two groups of pulse wave sensors, wherein the two groups of pulse wave sensors are separated by a set distance; wherein the controller receives the pulse waves obtained by the two groups of pulse wave sensors to calculate the transmission speed of the pulse waves, and calculates the carotid artery hardness according to the transmission speed.

The invention also provides an optical scanning type heart rate meter which comprises the pulse wave sensor.

The invention further provides a pulse wave monitoring method, which comprises the following steps:

the first step, emitting first laser;

step two, branching the first laser into a second laser and a reference light;

thirdly, adjusting the second laser to form a third laser which is incident to the blood vessel;

a fourth step of forming a fifth laser after adjusting the fourth laser reflected from the blood vessel;

fifth, the fifth laser and the reference light interfere to form sixth laser;

and a sixth step of receiving the sixth laser.

According to an embodiment of the present invention, in the third step, an output angle of the second laser light or an output channel of the second laser light is adjusted so that the third laser light can be incident on a blood vessel.

According to one embodiment of the invention, after the third step, the third laser light is focused to be incident on the blood vessel.

The invention also provides a wearable device, which comprises an electronic device, a first belt body and a second belt body, wherein the electronic device is connected with the first belt body and the second belt body, and the electronic device comprises the pulse wave sensor.

The pulse wave sensor, the wrist type pulse wave analyzer, the blood pressure monitor, the blood vessel hardness tester, the carotid artery hardness tester, the pulse wave monitoring method and the wearable device provided by the invention adopt an optical scanning mode, wherein the pulse wave sensor adopts a coherent detection method, and the signal to noise ratio of a receiving end is greatly improved. In addition, the directivity of the focused laser beam is changed by adopting an optical waveguide array or an optical waveguide switch and combining with phase control so as to improve the utilization rate of laser energy, thereby reducing the requirement on the power of a laser transmitter and correspondingly reducing the overall power consumption of the system so as to realize the aim of continuous monitoring.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention. In the accompanying drawings:

fig. 1 shows a schematic structure of an embodiment of the pulse wave sensor of the present invention.

Fig. 2 shows a schematic structure of a 1 to M multiplexing optical waveguide array of the pulse wave sensor of the present invention.

Fig. 3 shows a schematic structure of a 1 to N optical waveguide switch of the pulse wave sensor of the present invention.

Fig. 4A shows a schematic structural view of a conventional optical waveguide in the prior art.

Fig. 4B is a schematic top view of fig. 4A.

Fig. 5A is a schematic diagram (a) of the configuration in fig. 4A in which a phase control member is provided.

Fig. 5B is a schematic diagram (two) of the configuration in fig. 4A in which the phase control member is provided.

Fig. 5C is a schematic diagram (iii) of the configuration in which the phase control section is provided in fig. 4A.

Fig. 6A shows a perspective view of one output channel and a first microlens of the light guiding output member of the present invention.

Fig. 6B is a schematic side view of the structure of fig. 6A.

FIG. 7 is a schematic view showing a structure of a branching optical waveguide member of an embodiment of the pulse wave sensor of the present invention

Fig. 8 is a schematic diagram showing the structure of a receiving optical path member of an embodiment of the pulse wave sensor of the present invention.

Fig. 9 shows a schematic structural diagram of a photodetector of an embodiment of the pulse wave sensor of the present invention.

Fig. 10 is a schematic structural view of an embodiment of the wrist type pulse wave analyzer of the present invention.

Fig. 11 shows a schematic structural view of an embodiment of the blood pressure monitor of the present invention.

Fig. 12 shows a schematic structural view of an embodiment of the wearing device of the present invention.

Detailed Description

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Furthermore, although terms used in the present invention are selected from publicly known and commonly used terms, some terms mentioned in the present specification may be selected by the applicant at his or her discretion, the detailed meanings of which are described in relevant parts of the description herein. Furthermore, it is required that the present invention is understood, not simply by the actual terms used but by the meaning of each term lying within.

Fig. 1 shows a schematic structure of an embodiment of the pulse wave sensor of the present invention. As shown in fig. 1, the present invention provides a pulse wave sensor 11 based on an optical waveguide stage, which can be implemented using CVD techniques. The pulse wave sensor 11 includes a laser emitter 20, a shunt optical waveguide member 70, a light guiding output member 40, a light guiding input member 50, a receiving optical path member 80, and a photodetector 30. Wherein the laser transmitter 20 emits a first laser light 121. The branching optical waveguide member 70 receives the first laser light 121 and branches the first laser light 121 into the second laser light 124 and the reference light 122. The beam of the second laser light 124 is introduced into the light guiding output member 40, and the light guiding output member 40 receives and adjusts the second laser light 124 to form a third laser light 43, the third laser light 43 being able to be incident on the blood vessel 101. As shown, a pulse wave fluctuation graph 102 is marked on the blood vessel 101. The fourth laser beam 53 reflected from the blood vessel 101 carries pulse wave information, and the light guide input unit 50 receives and adjusts the fourth laser beam 53 and outputs the fifth laser beam 125. The fifth laser light 125 and the reference light 122 perform two-way interference on the receiving optical path member 80, and form a sixth laser light 123 after passing through the receiving optical path member 80. The sixth laser light 123 is received by the light detector 30.

Specifically, as shown in fig. 1, the fluctuation pattern curve 102 represents pulse fluctuation of the wall pressure change of the blood vessel 101, which changes the beam of the detection laser. The third laser light 43 (incident beam) reaches the blood vessel 101, and the optical path length of the fourth laser light 53 (reflected beam) reflected via the epidermis of the blood vessel 101 changes, thereby causing a phase change of the laser light beam. A peak of the pulse wave is generated in each cardiac cycle, and the frequency of the peak repetition is the heart rate. The sixth laser light 123 (interference signal) received by the photodetector 30 contains rich information of the pulse wave of the blood vessel 101, and these interference signals can be transferred to a subsequent stage data processing unit such as a monitoring workstation or the like for data analysis of the pulse wave or the like after being subjected to analog-to-digital sampling conversion, denoising processing or the like. The invention utilizes the optical scanning principle to continuously and accurately collect the pipe diameter change of the blood vessel in each cardiac cycle, thereby reflecting the change waveform of the pulse wave.

Furthermore, in order to improve the detection effectiveness of the laser beam, the pulse wave sensor 11 of the present invention controls the directionality of the emitted laser beam and the reflected light beam, and can automatically adjust to find the strongest pulse position of the blood vessel. Wherein the light guiding output part 40 and the light guiding input part 50 respectively realize incidence and emergence of the laser beam.

The light directing output member 40 may be a multiplexing optical waveguide array including 1 to M or a 1 to N optical waveguide switch, wherein M, N is an integer and greater than 1. In one embodiment, the 1 to M multiplexing optical waveguide array includes a plurality of stages 1 to 2 of spectroscopic optical path units, and a phase control member is provided on each of the output optical paths after multiplexing of 1 to M. Fig. 2 shows a schematic structure of a 1 to M multi-path optical waveguide array of the pulse wave sensor of the present invention, which is a 1 to 8-path optical waveguide array 46 including 3-stage 1 to 2 spectroscopic optical path units 41, and a phase control member 42 is provided on each output optical path. The second laser 124 forms 8 paths of output light through each stage of beam splitting optical path units 41, the phase control part 42 can adjust the phase of each path of output light, and all the phase control parts 42 can work in coordination to realize the angle control of the third laser 43 (incident beam).

In another embodiment, the 1 to N multi-path optical waveguide switch includes optical waveguide switching units of stages 1 to 2, and a phase control part is provided on a dual transmission optical path of each optical waveguide switching unit. Fig. 3 shows a schematic structure of a 1 to N multi-path optical waveguide switch of the pulse wave sensor of the present invention, which is a 1 to 8-path optical waveguide switch 47 including 3-stage 1 to 2 optical waveguide switch units 71, and a phase control member 42 is provided on a dual transmission optical path of each optical waveguide switch unit 71. The second laser beam 124 forms 8 output light beams through the optical waveguide switching units 71 at each stage. The phase control section 42 can adjust the phase of the output light of each optical waveguide switching unit 71, i.e., perform channel selection of the output light. All the phase control sections 42 can work in concert to realize channel control of the third laser light 43 (incident beam). In one embodiment, the optical waveguide switch unit 71 adopts an MZI (Mach-Zehnder interferometer ) structure.

Similarly, the light guiding input member 50 may be a multiplexing optical waveguide array including 1 to M or a 1 to N optical waveguide switch, wherein M, N is an integer and greater than 1. The light guiding input member 50 is capable of reflecting the angle or channel of the light beam is controlled.

Even if the relative position of the pulse wave sensor 11 and the blood vessel 101 is changed, the effectiveness of detection can be maintained by controlling the directivity of the laser beam by the light guide output member 40 and the light guide input member 50. For example, during the movement such as walking and running, the relative position of the pulse wave sensor 11 and the blood vessel 101 is changed, the signal to noise ratio of the receiving light path component 80 is reduced, when the pulse wave sensor 11 can change the phase control component 42 in a closed loop after the signal to noise ratio is reduced, the angle or channel of the laser beam is adjusted by the phase control component 42, so that the third laser 43 can be incident on the blood vessel 101, and the fifth laser can be received by the receiving light path component 80, thereby realizing the monitoring effectiveness, reducing the power consumption and improving the sensitivity.

Fig. 4A shows a schematic structural view of a conventional optical waveguide in the prior art. Fig. 4B is a schematic top view of fig. 4A. As shown, the transmission channel (basic waveguide structure) generally includes a substrate 61, a cladding 62, and a core waveguide 66. The laser beam may enter from one side of the core waveguide 66 and exit from the other side.

Fig. 5A is a schematic diagram (a) of the configuration in fig. 4A in which a phase control member is provided. Fig. 5B is a schematic diagram (two) of the configuration in fig. 4A in which the phase control member is provided. Fig. 5C is a schematic diagram (iii) of the configuration in which the phase control section is provided in fig. 4A. By way of example and not limitation, the phase control element 42 may be one of the following 3 configurations.

Referring to fig. 5A, the phase control member 42 includes a metal thin film 63 provided on the cladding 62 of the output optical path. In other words, the metal film 63 may be deposited on the cladding layer 62. The phase control member 42 adjusts the refractive index of the clad layer 62 by energizing and heating the metal thin film 63.

Referring to fig. 5B, the phase control section 42 includes liquid crystal cell layers 64, 67 and a double electrode 65. The liquid crystal cell layers 64, 67 may be a liquid crystal encapsulation glass layer and a liquid crystal material layer, respectively. The liquid crystal cell layers 64, 67 are stacked on the cladding layer 62 of the output optical path, and the liquid crystal material may be injected onto the cladding layer 62 in a manufacturing process, and the double electrode 65 is disposed on the liquid crystal layer 64. The refractive index of the liquid crystal material may be changed by an electric field, and the phase control section 42 adjusts the refractive index of the liquid crystal cell layers 64, 67 by changing the voltage of the double electrode 65.

Referring to fig. 5C, phase control member 42 includes a polymer layer 68 and a double electrode 65. A polymer layer 68 is disposed on the cladding 62 of the output optical path, and a polymer material may be injected onto the cladding 62 during the fabrication process, and a double electrode 65 is disposed on the polymer layer 68. Since the refractive index of the polymer material can also be changed by an electric field, the phase control section 42 adjusts the refractive index of the polymer layer 68 by changing the voltage of the double electrode 65.

In one embodiment of the present invention, the pulse wave sensor 11 further includes a first microlens and a second microlens. The third laser light 43 passes through the first microlens to reach the blood vessel 101, and the fourth laser light 53 passes through the second microlens to reach the light guide input member 50. Preferably, the first microlenses and the light-guiding output section 40 are integrally formed. Specifically, the first microlenses may be placed within the light-guiding output member 40, i.e., lens-function processing is performed on each of the optical waveguides exiting the light-guiding output member 40 at the interface of the waveguides and free space. Similarly, the second microlens and the light guiding input section 50 are integrally formed, i.e., each optical waveguide introduced into the light guiding input section 50 is subjected to lens function processing at the interface of the waveguide and the free space. It will be appreciated that the first and second microlenses may also employ separate optical lenses to achieve the focusing of the light beam.

Fig. 6A shows a perspective view of one output channel and a first microlens of the light guiding output member of the present invention. Fig. 6B is a schematic side view of the structure of fig. 6A. A specific description will be given of one output path of the output end of the light guiding output member 40 and one first microlens 48 as an example. Referring to fig. 6B, the left side is one output path of the output end of the light guiding output member 40, and the right side is the first microlens 48. The output channel (basic waveguide structure) includes a substrate 61, a cladding 62, and a core waveguide 66. Cladding 62 is grown on substrate 61 by a high temperature oxidation process and core waveguide 66 extends through the output path and first microlenses 48. The first microlens 48 is a layered structure including a plurality of silicon oxynitride layers 69-1, 69-2, 69-3 having different refractive indices disposed around the core waveguide 66. Each of the silicon oxynitride layers 69-1, 69-2, 69-3 is grown on the next layer by a deposition method. In fact, two or three silicon oxynitride layers may be provided under the core waveguide 66, or two or three silicon oxynitride layers may be provided under the core waveguide 66, each of which is changed to a silicon oxynitride layer having a different refractive index by a process. The farther from the core waveguide 66 the refractive index of the silicon oxynitride layer is lower. Taking the example of a multi-path optical waveguide array implementation, the laser beams enter from the left side of the core waveguide 66, all radiate from the first microlens 48 with identical elliptical cone beams, and the exit angles of these elliptical cone beams are uniform. When these beams are superimposed in the far field, the far field beams can form controllable constructive or destructive interference at different spatial locations, i.e. controllable focusing and scanning of the laser beams can be achieved, depending on the different controlled phases. In practice, these controllably focused beams will be set to predetermined positions corresponding to the vessel 101.

The second microlenses 52 are identical in construction and operation to the first microlenses 48. The fourth laser light 53 reflected from the blood vessel 101 passes through the second microlens to reach the light guide input section 50.

On the other hand, the laser emitter 20 employs a near infrared laser emitter. The near infrared laser has the greatest advantages that the laser has extremely high luminous efficiency and luminous intensity, and the light beam of the near infrared laser has very good directivity, so that the near infrared laser can be effectively focused on a blood vessel part to be monitored. Meanwhile, due to the good linewidth quality of the near infrared laser, coherent detection is realized after light reflected from a blood vessel is converged with part of local reference light.

Fig. 7 is a schematic structural view of a branching optical waveguide member of an embodiment of the pulse wave sensor of the present invention. As shown, the shunt optical waveguide member 70 includes a 2X2 optical coupler 71. The optical coupler 71 realizes the spectroscopic functions of 1 to 2. The first laser light 121 is split into a second laser light 124 and a reference light 122.

Fig. 8 is a schematic diagram showing the structure of a receiving optical path member of an embodiment of the pulse wave sensor of the present invention. The receiving optical path part 80 includes one 2X4 double optical interferometer composed of four 2X2 couplers 71. The reference light 122 and the fifth laser light 125 pass through the receiving optical path member 80 to generate a sixth laser light 123 having two pairs of constructive/destructive outputs.

Fig. 9 shows a schematic structural diagram of a photodetector of an embodiment of the pulse wave sensor of the present invention. The photodetector 30 is composed of two independent balanced detectors 31, 32, having a balanced structure. The balanced detectors 31, 32 detect two pairs of constructive/destructive output signals of the sixth laser 123, respectively.

The invention also describes a wrist type pulse wave analyzer. Fig. 10 is a schematic structural view of an embodiment of the wrist type pulse wave analyzer of the present invention. The wrist pulse wave analyzer 100 includes a housing 81 and belt bodies 91 and 92 connected to the housing 81, and the housing 81 includes a pulse wave sensor 11. The bands 91 and 92 may be attached to the wrist of the user, so that the pulse wave sensor 11 of the wrist type pulse wave monitor 100 can monitor the pulse wave of the human body in real time.

The invention also describes a blood pressure monitor. Fig. 11 shows a schematic structural view of an embodiment of the blood pressure monitor of the present invention. The blood pressure monitor 200 comprises at least two sets of pulse wave sensors 11, 11' as described above and a controller (not shown) and is spaced apart by a set distance. The time required for the pulse wave to propagate from the pulse wave sensor 11 to the pulse wave sensor 11' in the same cardiac cycle is the Pulse Transit Time (PTT). From the measured pulse wave transit time, the Pulse Wave Velocity (PWV) can be calculated, which can be used to estimate the change in blood pressure, since the PWV of the pulse wave depends on the blood pressure. For example, if the interval between the two pulse wave sensors 11, 12 is 1cm, the controller receives the pulse waves obtained by the two pulse wave sensors 11, 12, calculates PTT from the phase difference of the two pulse waves, and further obtains PWV of the pulse waves, and calculates blood pressure of the human body. In the case of a typical PWV wave speed of 3m/s, the PTT at this time is 3ms, which can be detected by the blood pressure monitor 100. When the blood pressure rises, it causes the blood vessel to be tensioned and the blood vessel wall to be hardened; the hardened blood vessel drives the pulse wave faster, resulting in a shorter PTT. Conversely, when the blood pressure decreases, PTT increases. PTT or PWV can effectively predict blood pressure in a short time, so the PTT or PWV can be used as a blood pressure change monitoring means, and particularly can easily monitor the rapid change of blood pressure caused by physical or mental activities or emotion related to the concentric vascular diseases.

Preferably, the two sets of pulse wave sensors 11, 11' can share the same laser transmitter.

The invention also describes a vascular hardness tester. Similar to the blood pressure monitor 200, the vascular stiffness meter includes a controller and two sets of pulse wave sensors as described above, spaced apart by a set distance. The PTT or PWV is obtained through two groups of pulse wave sensors, so that the vascular hardness can be predicted, and the method can be used as a means for monitoring the vascular hardness.

The invention also describes a carotid artery hardness tester. The carotid artery hardness tester comprises a controller and two groups of pulse wave sensors, wherein the pulse wave sensors are separated by a set distance. The PTT or PWV is obtained by the two groups of pulse wave sensors, and the carotid artery hardness can be predicted.

The invention also describes an optical scanning type heart rate meter. The optical scanning type heart rate meter comprises the pulse wave sensor, and the pulse wave sensor is used for measuring and analyzing the pulse wave of a human body. Heart rate and arrhythmia can be easily monitored as a heart rate meter, for example, by analysis of pulse waves.

The invention also provides a pulse wave monitoring method, referring to fig. 1, comprising the following steps:

first, emitting a first laser 121;

a second step of splitting the first laser 121 into a second laser 124 and a reference light 122;

third, the second laser beam 124 is adjusted to form a third laser beam 43, which is incident on the blood vessel 101;

fourth, forming a fifth laser beam 125 by adjusting the fourth laser beam 53 reflected from the blood vessel 101;

fifth, the fifth laser 125 interferes with the reference light 122 to form a sixth laser 123;

and a sixth step of receiving the sixth laser light 123.

Preferably, in the third step, the output angle of the second laser light 124 is adjusted or the output channel of the second laser light 124 is adjusted, so that the third laser light 43 can be incident on the blood vessel 101.

Preferably, after the third step, the third laser light 43 is focused to be incident on the blood vessel 101.

The invention further provides a wearable device. Fig. 12 shows a schematic structural diagram of one embodiment of the wearable device of the present invention. As shown, the wearable device 300 includes an electronic device 110, a first strap 128 and a second strap 129, and the electronic device 110 is connected to the first strap 128 and the second strap 129. The electronic device 110 may include the pulse wave sensor described above. It is easy to understand that the first belt 128 and the second belt 129 can be attached to the wrist of the user, so that the pulse wave sensor can monitor the pulse wave of the human body in real time. The accuracy of pulse wave detection of the wearable device 300 is further improved by the cooperation of the electronic device 110, the first belt 128 and the second belt 129.

In addition, the electronic device 110 may further include a time display device, a timing device, a wireless transmission device, a positioning device, a navigation device, or a physiological information monitoring device. The wearable device 300 has the characteristics of low cost, small volume, portability, low power consumption and long standby time, and the wireless transmission device can wirelessly transmit the monitoring result to the mobile phone and store the monitoring result, can also display the monitoring result by using the mobile phone app and upload the monitoring result to the server. The system has the functions of real-time and durable monitoring and analyzing the shape and the conduction speed of the pulse wave of the human body, and a user can conveniently and rapidly know the health condition of the user on the premise of not affecting work, study and exercise. The monitoring of the vascular function health condition is realized through the difference between the characteristic value of the pulse wave and the numerical value of the monitored subject. These functions and designs can be concentrated on one optical chip by integrated optical technology, its small volume making it applicable to wearable devices.

The pulse wave sensor, the pulse wave analyzer, the vascular hardness monitor, the heart rate meter, the blood pressure monitor, the pulse wave monitoring method and the wearable device provided by the invention adopt an optical scanning mode, wherein the pulse wave sensor adopts a coherent detection method, and the signal to noise ratio of a receiving end is greatly improved. In addition, the directivity of the focused laser beam is changed by adopting an optical waveguide array or an optical waveguide switch and combining with phase control so as to improve the utilization rate of laser energy, thereby reducing the requirement on the power of a laser transmitter and correspondingly reducing the overall power consumption of the system, and realizing 24/7 noninvasive monitoring of heart rate, blood pressure and pulse wave.

It will be apparent to those skilled in the art that various modifications and variations can be made to the above-described exemplary embodiments of the present invention without departing from the spirit and scope of the invention. Therefore, it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.

Claims

1. A pulse wave sensor, comprising:

a laser emitter that emits a first laser light;

a photodetector for receiving the sixth laser light;

the light guiding output component comprises a multi-path optical waveguide array of 1 to M or a 1 to N optical waveguide switch, and the light guiding input component comprises a multi-path optical waveguide array of 1 to M or a 1 to N optical waveguide switch;

wherein M, N is an integer and greater than 1;

the multi-path optical waveguide array from 1 to M comprises multi-level 1 to 2 light splitting optical path units, and after the multi-path light splitting from 1 to M is realized, phase control components are arranged on all transmission optical paths of the M paths so as to change the phases of light beams in the transmission optical paths; the 1 to N optical waveguide switches comprise optical waveguide switch units of multiple stages 1 to 2, and the phase control component is arranged on a double transmission optical path in each optical waveguide switch unit;

the pulse wave sensor further comprises a first micro lens and a second micro lens, and the third laser reaches the blood vessel through the first micro lens; the fourth laser light passes through the second microlens to reach the light guiding input section; the first micro-lens and the second micro-lens are of a layered structure and comprise a plurality of silicon oxynitride layers with different refractive indexes; the first microlenses and the light guiding output members are integrally formed, and the second microlenses and the light guiding input members are integrally formed.

2. A pulse wave sensor according to claim 1, wherein the phase control means comprises a metal film provided on the transmission optical path, and the phase control means adjusts the refractive index of the material of the transmission optical path by electrically heating the metal film.

3. A pulse wave sensor according to claim 1, wherein the phase control means comprises a liquid crystal layer provided on the transmission optical path and a double electrode provided on the liquid crystal layer, the phase control means adjusting the refractive index of the liquid crystal layer by changing the voltage of the double electrode.

4. A pulse wave sensor according to claim 1, wherein the phase control means comprises a polymer layer arranged on the output optical path and a double electrode arranged on the polymer layer, the phase control means adjusting the refractive index of the polymer layer by varying the voltage of the double electrode.

5. A pulse wave sensor as defined in claim 1, wherein said laser transmitter is a near infrared laser transmitter.

6. A pulse wave sensor as set forth in claim 1 wherein said receiving optical path means comprises a dual optical interferometer.

7. A wrist type pulse wave analyzer comprising a housing and a band connected to the housing, the housing comprising the pulse wave sensor according to any one of claims 1 to 6.

8. A blood pressure monitor comprising a controller and at least two sets of pulse wave sensors according to any one of claims 1 to 6, the two sets of pulse wave sensors being spaced apart by a set distance;

wherein the controller receives the pulse waves obtained by the two groups of pulse wave sensors to calculate the transmission speed of the pulse waves, and calculates the blood pressure according to the transmission speed.

9. A blood pressure monitor as claimed in claim 8, wherein the two sets of pulse wave sensors share the same laser transmitter.

10. A vascular hardness tester, comprising a controller and at least two sets of pulse wave sensors according to any one of claims 1 to 6, the two sets of pulse wave sensors being spaced apart by a set distance;

wherein the controller receives the pulse waves obtained by the two groups of pulse wave sensors to calculate the conduction velocity of the pulse waves, and calculates the hardness of the blood vessel according to the conduction velocity.

11. A carotid artery hardness tester, comprising a controller and at least two sets of pulse wave sensors according to any one of claims 1 to 6, the two sets of pulse wave sensors being spaced apart by a set distance;

wherein the controller receives the pulse waves obtained by the two groups of pulse wave sensors to calculate the transmission speed of the pulse waves, and calculates the carotid artery hardness according to the transmission speed.

12. An optical scanning heart rate meter comprising a pulse wave sensor as claimed in any one of claims 1 to 6.

13. A pulse wave monitoring method suitable for the pulse wave sensor according to claim 1, comprising the steps of:

the first step, emitting first laser;

step two, branching the first laser into a second laser and a reference light;

fifth, the fifth laser and the reference light interfere to form sixth laser;

and a sixth step of receiving the sixth laser.

14. A pulse wave monitoring method according to claim 13, wherein in the third step, the output angle of the second laser light is adjusted or the output channel of the second laser light is adjusted so that the third laser light can be incident on the blood vessel.

15. A pulse wave monitoring method according to claim 13, wherein after the third step, the third laser light is focused to impinge on the blood vessel.

16. A wearable device, comprising an electronic device, a first belt body and a second belt body, wherein the electronic device is connected to the first belt body and the second belt body, and the electronic device comprises the pulse wave sensor according to any one of claims 1 to 6.

17. A wearable device comprising an electronic device, a first belt and a second belt, the electronic device being connected to the first belt and the second belt, the electronic device comprising a blood pressure monitor according to any one of claims 8 to 9.