JP2009201894A - Pulse wave detecting device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pulse wave detecting device detecting a pulse wave even when a finger is put on a pulse wave detecting part by pressurization. <P>SOLUTION: The pulse wave detecting device is provided with the pulse wave detecting part 11 including: a light emitting part 23 for emitting light toward the surface of the finger F; a light receiving part 24 for receiving the light to be reflected from the finger in the light emitted from the light emitting part; and a sensor case 21 for storing the light emitting part and the light receiving part, where the surface of the finger is placed. The surfaces 27, 28 for placing the finger thereon in the sensor case has a groove part 25 along the longitudinal direction of the finger. The groove part is configured to have a shape to provide a moment for supporting the finger with a plurality of places when the finger is placed. The light emitting part and the light receiving part are positioned at positions corresponding to the finger supporting places when the finger is placed on the groove part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pulse wave detection device.

Conventionally, a pulse wave detection device capable of detecting and displaying pulse wave information such as a pulse wave and a pulse rate is known. The pulse wave detection device irradiates light toward a finger surface from a light emitting unit configured with, for example, an LED (Light Emitting Diode), and the like, and configures light reflected from the finger (blood vessel) with a PD (Photo Diode) or the like. By receiving light at the received light receiving unit, a change in blood volume is detected as a change in the amount of received light, and a pulse wave, a pulse rate, and the like can be detected based on the detection result (see, for example, Patent Document 1). . As shown in FIG. 8, the pulse wave measurement device (pulse wave detection device) of Patent Document 1 is composed of a translucent plate 101 made of a glass plate in which the surface of the pulse wave detection unit 100 is formed flat. When the LED (light emitting unit) 103 emits light toward the surface of the finger F with the finger (finger belly) F in close contact with the outer surface 102 of the optical plate 101, the phototransistor (light receiving unit) 104 is Of the light emitted from the LED 103, the light reflected from the finger F side can be received.
JP-A-9-108192

  By the way, in the pulse wave detection device of Patent Document 1 described above, since the finger F is arranged so as to press the surface 102 of the pulse wave detection unit 100, the blood in the region near the abdomen 105 of the finger F due to the pressing load of the finger F. There was a problem that the flow stopped and the pulse wave could not be detected.

  Therefore, the present invention provides a pulse wave detection device that can detect a pulse wave even if the finger wave is placed against the pulse wave detection unit.

  In order to solve the above-described problems, a pulse wave detection device according to the present invention reflects a light emitting unit that emits light toward the finger surface, and the light emitted from the light emitting unit is reflected from the finger side. A light-receiving unit capable of receiving light; and a pulse wave detection unit including the light-emitting unit and the light-receiving unit and a sensor case on which the finger surface can be placed; and the finger of the sensor case A groove portion is formed along the longitudinal direction of the finger on the surface on which the finger is placed, and the groove portion is configured in a shape having moments for supporting the finger at a plurality of locations when the finger is placed, When the finger is placed in the groove, the light emitting part and the light receiving part are arranged at a position corresponding to the support part of the finger.

  With this configuration, when a finger is pressed into the groove and brought into close contact, the finger is supported at a plurality of locations in the groove, so that the finger positioned in the groove is pressed with a pressing force. The region where the blood flow stops and the region where the pressing force does not affect and the blood flow does not stop are formed. Therefore, the light emitting part and the light receiving part are arranged at a desired position (a position corresponding to the finger support part) of the sensor case, and light is emitted from the light emitting part to a region where blood flow is not stopped in the groove part. The pulse wave can be detected by receiving the reflected light at the light receiving unit. That is, the pulse wave can be detected even if the finger is pressed against the pulse wave detection unit.

In the pulse wave detection device according to the present invention, a cross section of the groove portion along the short direction of the finger is formed in a V shape, and the fingers are in contact with the side surfaces of the V shape groove portion. The light emitting part and the light receiving part are respectively arranged at positions corresponding to the contact points.
With this configuration, when a finger is pressed into the groove so as to be in close contact with each other, the finger comes into contact with the side surfaces located on both sides of the V-shaped groove, and the region near the contacted portion has its pressing force. The finger is pressed under the influence of blood flow and blood flow stops. On the other hand, the blood flow does not stop at the substantially central portion in the cross section of the finger in the short direction because the pressing force is not affected. Therefore, by arranging the light emitting part on one side of the groove part and the light receiving part on the other side so that the optical path is formed in the region where the blood flow is not stopped, Can be detected.

Furthermore, in the pulse wave detection device according to the present invention, a cross section of the groove portion along the short direction of the finger is formed in a W shape, and the finger is brought into contact with a central convex portion of the W shape groove portion. At the same time, the fingers are in contact with the side surfaces located on both sides of the W-shaped groove, and the light emitting unit and the light receiving unit are respectively disposed at positions facing the finger contact portions on the side surfaces. It is characterized by that.
With this configuration, when the finger is pressed into the groove portion so as to be brought into close contact, the finger comes into contact with the central convex portion of the W-shaped groove portion and the side surfaces located on both sides of the groove portion. As a result, the finger is pressed in the region near the portion that is in contact with the central convex portion of the groove, and the blood flow is stopped due to the pressing force. On the other hand, the blood flow does not stop because the pressing force does not affect both side portions (near the portions in contact with both side surfaces of the groove portion) in the cross section of the finger in the short direction. Therefore, by arranging the light emitting part on one side of the groove part and the light receiving part on the other side so that the optical path is formed in the region where the blood flow is not stopped, Can be detected.

  According to the pulse wave detection device according to the present invention, when the finger is brought into close contact with the groove portion, the finger is supported at a plurality of locations in the groove portion. A region where the blood flow stops due to being pressed by the pressing force and a region where the blood flow does not stop without being affected by the pressing force are formed. Therefore, by arranging the light emitting part and the light receiving part at a desired position of the sensor case, irradiating light from the light emitting part to the region where the blood flow does not stop in the groove part, and receiving the reflected light by the light receiving part A pulse wave can be detected. In other words, there is an effect that the pulse wave can be detected even if the finger is pressed against the pulse wave detection unit.

(First embodiment)
Next, a first embodiment of a pulse wave detection device according to the present invention will be described with reference to FIGS.

(Pulse wave detector)
FIG. 1 is a schematic block diagram of the pulse wave detection device.
As shown in FIG. 1, the pulse wave detection device 10 irradiates light on the finger F, receives the reflected light, and converts the detection result into a signal from the pulse wave detection unit 11 and the pulse wave detection unit 11. CPU 12 for receiving various signals and performing various calculations, a display unit 13 for displaying the waveform of a pulse wave from the calculation result by CPU 12, an input unit 14 for giving various setting conditions to CPU 12, A storage unit 15 including a RAM that stores pulse wave data converted into a digital signal and the like, and an oscillation unit 16 that supplies a clock to the CPU 12 are provided.

  In addition, each part which comprises other than the pulse wave detection part 11 is comprised with a personal computer, for example, the input part 14 respond | corresponds to a keyboard and the display part 13 corresponds to a display, respectively. Further, a part other than the pulse wave detection unit 11 may be constituted by a wristwatch type device, or the result may be displayed on the television based on the information from the pulse wave detection unit 11.

(Pulse wave detector)
FIG. 2 is a perspective view of the pulse wave detection unit 11.
As shown in FIG. 2, the pulse wave detection unit 11 is arranged in a box-shaped sensor case 21, a component storage space 22 configured inside the sensor case 21, and a light emitting unit 23 made of, for example, an LED, a PD And a light receiving unit 24 comprising: In addition, the length along the longitudinal direction of the finger in the sensor case 21 is formed with a length substantially equal to the first joint of the finger.

  On the upper surface 21a of the sensor case 21, a groove portion 25 is formed over the entire length along the longitudinal direction of the finger. The groove portion 25 has a V-shaped cross section along the short side direction of the finger (direction perpendicular to the longitudinal direction of the finger). Translucent plates 29 and 29 made of a translucent glass plate are attached to the inclined side surfaces 27 and 28 constituting the V-shaped groove 25, and the finger F is placed on the translucent plates 29 and 29. It comes to adhere. Further, a light emitting unit 23 and a light receiving unit 24 are arranged on the component housing space 22 side of the light transmitting plates 29 and 29 so that the finger F is directed through the light transmitting plates 29 and 29, respectively. The light emitting unit 23 and the light receiving unit 24 are connected to a circuit board (not shown) arranged in the component storage space 22. The circuit 12 is configured to be communicable with the CPU 12 so that the detection result of the light receiving unit 24 can be calculated and a pulse wave or the like can be displayed.

(Function)
Next, an operation of detecting a pulse wave by placing a finger on the pulse wave detector 11 will be described.
FIG. 3 is a front view when a finger is placed on the pulse wave detector 11.
As shown in FIG. 3, when the finger F is brought into close contact with the groove portion 25 of the pulse wave detection unit 11, both side portions of the finger F are provided on the side surfaces 27 and 28 of the groove portion 25. , 29 are arranged so as to contact each other. Here, by pressing the finger F into the groove portion 25, the side regions 31 and 32 of the finger F in contact with both side surfaces 27 and 28 are compressed, and blood flow in the side regions 31 and 32 is stopped. Will end up.

  On the other hand, in the regions other than the side regions 31 and 32 of the finger F, in particular, the central region 33 of the finger F is not compressed even if it is brought into close contact with the groove 25 so as to press the finger F, and blood flow is prevented. There is no stopping.

  That is, while the finger F is placed in the groove portion 25, the finger F is supported by the both side surfaces 27 and 28, and when the finger F is completely placed in the groove portion 25, It is possible to form an area where the finger F is pressed and an area where the finger F is not pressed.

  Further, light is emitted from the light emitting unit 23 toward the finger F in a state where the finger F is disposed in the groove 25 in this way. The light emitting unit 23 is disposed in the component storage space 22 and irradiates light toward the finger F through the light transmitting plate 29. Then, the irradiated light is absorbed, diffused, and reflected by a tissue such as a blood vessel (blood), fat, or muscle inside the finger F, and a part of the irradiated light is detected by the light receiving unit 24. The light detected by the light receiving unit 24 fluctuates with a change in blood volume due to blood vessel pulsation. The light receiving unit 24 receives light, generates a pulse wave signal corresponding to a change in the amount of received light, and outputs the pulse wave signal to the CPU 12.

  That is, since the amount of reflected light of the light emitted from the light emitting unit 23 varies according to the blood flow variation of the capillary blood vessels in the central region 33 inside the finger F, the light receiving unit 24 pulsates the capillary blood vessels, that is, the pulse wave. It is possible to receive reflected light in accordance with. Thereby, the light receiving unit 24 can generate a pulse wave signal.

  Since the gap 35 formed between the lower end folded portion 34 of the groove 25 and the finger F can be a cause of signal noise, the groove 25 is preferably formed to be as small as possible. That is, by forming the groove portion 25 so that the gap 35 becomes small, noise can be suppressed and the S / N ratio can be improved.

  According to the present embodiment, since the groove portion 25 is formed in a V-shaped cross section along the longitudinal direction of the finger F on the upper surface of the sensor case 21, when the finger F is pressed into the groove portion 25 so as to be in close contact, The finger F is supported on both side surfaces 27 and 28 in the groove 25. Accordingly, the side regions 31 and 32 where the blood flow is stopped by being pressed by the pressing force on the finger F located in the groove 25 and the central region 33 where the pressing force is not affected and the blood flow is not stopped are formed. Is done. As a result, the light emitting unit 23 and the light receiving unit 24 are disposed on the component housing space 22 side of the light transmitting plates 29 and 29 provided on the both side surfaces 27 and 28, and the central region 33 is irradiated with light from the light emitting unit 23. The pulse wave can be detected by receiving the reflected light at the light receiving unit 24. That is, even if it arrange | positions so that the finger F may be pressed on the pulse-wave detection part 11, a pulse wave can be detected reliably.

(Second embodiment)
Next, a second embodiment of the pulse wave detection device according to the present invention will be described with reference to FIGS. In addition, since this embodiment differs from 1st embodiment only in the shape of a groove part, and about another structure, it is substantially the same, Therefore The same code | symbol is attached | subjected to the same location and detailed description is abbreviate | omitted.

(Pulse wave detector)
FIG. 4 is a perspective view of the pulse wave detection unit 111.
As shown in FIG. 4, the pulse wave detection unit 111 includes a box-shaped sensor case 121, and a light emitting unit 23 and a light receiving unit 24 disposed in a component storage space 122 configured inside the sensor case 121. I have. In addition, the length along the longitudinal direction of the finger in the sensor case 121 is formed with a length substantially equal to the first joint of the finger.

  On the upper surface 121a of the sensor case 121, a groove 125 is formed over the entire length along the longitudinal direction of the finger. The groove 125 has a W-shaped cross section along the short direction of the finger. Translucent plates 29 and 29 made of a translucent glass plate are attached to the inclined side surfaces 127 and 128 constituting the W-shaped groove 25, and the finger F is placed on the translucent plates 29 and 29. It comes to contact. Further, the light emitting unit 23 and the light receiving unit 24 are disposed on the component housing space 122 side of the light transmitting plates 29 and 29 so that the finger F is directed through the light transmitting plates 29 and 29, respectively. The light emitting unit 23 and the light receiving unit 24 are connected to a circuit board (not shown) arranged in the component storage space 122. Via this circuit board, it is configured to be communicable with the CPU 12 (see FIG. 1), so that the detection result of the light receiving unit 24 can be calculated and a pulse wave or the like can be displayed.

  Further, a central convex portion 130 is formed along the cross-sectional shape on the bottom surface of the groove portion 125. The central convex portion 130 is configured such that when the finger F is disposed in the groove portion 125, the both sides of the finger F abut on the abdomen 137 of the finger F before the abutment on both side surfaces 127 and 128 of the groove 125. Has been.

(Function)
Next, an operation of detecting a pulse wave by placing a finger on the pulse wave detection unit 111 will be described.
FIG. 5 is a front view when the finger F is placed on the pulse wave detection unit 111.
As shown in FIG. 5, when the finger F is pressed against the groove 125 of the pulse wave detector 111 so as to be pressed, the abdomen 137 of the finger F is first brought into contact with the central convex portion 130 of the groove 125, and the finger F Is pressed into the groove 125, the both sides of the finger F are arranged so as to abut against the light transmitting plates 29, 29 provided on both side surfaces 127, 128 of the groove 125. Here, by pressing the finger F into the groove 125, the central region 133 of the finger F that is in contact with the central convex portion 130 is compressed, and blood flow in the central region 133 is stopped.

  On the other hand, in the regions other than the central region 133 of the finger F, the side regions 131 and 132 of the finger F, in particular, are not compressed even if they are brought into close contact with the groove 125 so as to press the finger F, and blood flow is prevented. There is no stopping.

  That is, while the finger F is placed in the groove 125, the finger F is supported by the both side surfaces 127 and 128, and when the finger F is completely placed in the groove 125, It is possible to form an area where the finger F is pressed and an area where the finger F is not pressed.

  In addition, light is emitted from the light emitting unit 23 toward the finger F in a state where the finger F is disposed in the groove portion 125 in this way. Then, the irradiated light is absorbed, diffused, and reflected by a tissue such as a blood vessel (blood), fat, or muscle inside the finger F, and a part of the irradiated light is detected by the light receiving unit 24. The light detected by the light receiving unit 24 fluctuates with a change in blood volume due to blood vessel pulsation.

  That is, since the amount of reflected light of the light emitted from the light emitting unit 23 varies according to the blood flow variation of the capillaries in the side regions 131 and 132 inside the finger F, the light receiving unit 24 pulsates the capillaries, That is, it becomes possible to receive reflected light according to the pulse wave. Thereby, the light receiving unit 24 can generate a pulse wave signal.

  In addition, since the gaps 135 and 135 formed between the lower end folded portions 134 and 134 of the groove 25 and the finger F can cause signal noise, the groove 125 is preferably formed to be as small as possible. . That is, by forming the groove portion 125 so that the gap 135 becomes small, noise can be suppressed and the S / N ratio can be improved.

  According to the present embodiment, since the groove portion 125 is formed in a W-shaped cross section along the longitudinal direction of the finger F on the upper surface of the sensor case 121, when the finger F is pressed and pressed into the groove portion 125, The abdomen portion 137 of the finger F is supported by the central convex portion 130 in the groove portion 125, and both side portions of the finger F are brought into contact with both side surfaces 127 and 128 in the groove portion 125. Accordingly, the finger F positioned in the groove 125 is formed with a central region 133 where the blood flow is stopped by being pressed by the pressing force, and side regions 131 and 132 where the pressing force is not affected and the blood flow is not stopped. Is done. As a result, the light emitting unit 23 and the light receiving unit 24 are arranged on the component housing space 122 side of the light transmitting plates 29 and 29 provided on the both side surfaces 127 and 128, and light is emitted from the light emitting unit 23 to the side regions 131 and 132. The pulse wave can be detected by receiving the reflected light by the light receiving unit 24. That is, even if it arrange | positions so that the finger F may be pressed on the pulse-wave detection part 111, a pulse wave can be detected reliably.

  The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. That is, the specific shape, configuration, and the like given in the present embodiment are merely examples, and can be changed as appropriate.

  For example, in the present embodiment, the case where the groove 25 (125) is formed in a V-shaped or W-shaped cross section has been described, but the gap 35 (135 between the finger F and the bottom surface of the groove 25 (125) is described. ) May be formed in a circular arc shape at the lower end folded portion 34 (134) of the groove 25 (125) (see FIG. 6).

  In the present embodiment, the light emitting unit 23 is disposed on one side surface 27 (127) of the groove 25 (125) and the light receiving unit 24 is disposed on the other side surface 28 (128). The unit 23 and the light receiving unit 24 may be arranged in parallel on the same side surface to detect a pulse wave.

  Furthermore, in this embodiment, the groove 25 (125) is formed over the entire length of the sensor case 21 (121). However, in order to suppress the entry of external light into the groove 25 (125), the groove 25 (125 The wall 40 (140) may be formed at both ends of the) (see FIG. 7).

It is a schematic block diagram of a pulse wave detection device in an embodiment of the present invention. It is a perspective view of the pulse wave detection part in a first embodiment of the present invention. It is a front view when a finger | toe is arrange | positioned at the pulse wave detection part in 1st embodiment of this invention. It is a perspective view of the pulse wave detection part in a second embodiment of the present invention. It is a front view when a finger | toe is arrange | positioned at the pulse-wave detection part in 2nd embodiment of this invention. It is a front view which shows another aspect of the sensor case in embodiment of this invention. It is a perspective view which shows another aspect of the sensor case in embodiment of this invention. It is a front view when arrange | positioning a finger | toe in the conventional pulse-wave detection part.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 ... Pulse wave detection apparatus 11 ... Pulse wave detection part 21 ... Sensor case 23 ... Light emission part 24 ... Light reception part 25 ... Groove part 27, 28 ... Side surface 33 ... Center area | region (non-pressing location) 111 ... Pulse wave detection part 121 ... Sensor Case 125 ... Groove 127, 128 ... Side 130 ... Central convex 131, 132 ... Side region (non-pressed part) F ... Finger

Claims (3)

A light emitting unit that emits light toward the finger surface;
A light receiving unit capable of receiving light reflected from the finger side of the light emitted from the light emitting unit;
In the pulse wave detection device having a pulse wave detection unit including the light emitting unit and the light receiving unit, and a sensor case on which the finger surface can be placed,
On the surface of the sensor case on which the finger is placed, a groove is formed along the longitudinal direction of the finger,
The groove is configured in a shape having a moment to support the finger at a plurality of locations when the finger is placed,
The pulse wave detection device, wherein when the finger is placed in the groove, the light emitting part and the light receiving part are arranged at a position corresponding to the support part of the finger. A cross section along the short direction of the finger in the groove is formed in a V shape,
The said light-emitting part and the said light-receiving part are each arrange | positioned in the position corresponding to the contact location of this finger | toe each with the said finger | toe contact | abuts to the side surface of this V-shaped groove part. Pulse wave detector. A cross section along the short direction of the finger in the groove is formed in a W shape,
The fingers are in contact with the central convex portion of the W-shaped groove, and the fingers are in contact with the side surfaces located on both sides of the W-shaped groove,
2. The pulse wave detection device according to claim 1, wherein the light emitting unit and the light receiving unit are respectively disposed at positions on the side surface facing a contact portion of the finger.

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