JP6853712B2 - Blood oxygen saturation measuring device - Google Patents

Description

The present invention relates to a blood oxygen saturation measuring device for measuring the blood oxygen saturation of a living body.

As a blood oxygen saturation measuring device, light of two different wavelengths from red to near infrared is projected onto a living body to detect it, and based on this, biological information is detected without restraining the living body. The device is known (see, for example, Patent Document 1).

JP-A-2017-000743

However, in the device described in Patent Document 1, since light is projected onto a living body for measurement, the light is projected onto a living body sleeping in a dark place to give the living body a sense of discomfort such as glare and sleep. May interfere.

One aspect of the present invention is a blood oxygen saturation measuring device that measures the oxygen saturation in the blood of a living body, and is used for an upper jaw mouthpiece that is detachably attached to the upper jaw of the living body and an upper jaw mouthpiece. A light receiving part of an RGB camera with an infrared cut filter removed, which is attached and irradiates light of first and second wavelengths different from each other, and a light received by the irradiating part and transmitted through the upper lip of the living body. A unit, a wavelength determination unit that determines the wavelength of the light received by the light receiving unit, an intensity calculation unit that calculates the light receiving intensity of the light received by the light receiving unit, and a time change of the light receiving intensity calculated by the intensity calculation unit. Based on the absorbance change amount calculation unit that calculates the amount of change in absorbance by the living body based on, the wavelength of light determined by the wavelength determination unit, and the amount of change in absorbance calculated by the absorbance change amount calculation unit. A housing that stores a blood oxygen saturation calculation unit that calculates the oxygen saturation in the blood of a living body, a light receiving unit, a wavelength determination unit, an intensity calculation unit, an absorbance change calculation unit, and a blood oxygen saturation calculation unit. , Equipped with. The housing is attached to a member fixedly arranged in the room so that the light receiving portion faces the living body.

According to the present invention, the blood oxygen saturation is measured based on the light transmitted through the living body by being irradiated by the irradiation unit attached to the maxillary mouthpiece, so that the living body does not feel uncomfortable during sleep. The oxygen saturation in the blood can be measured.

The schematic diagram which shows the whole structure of the blood oxygen saturation measuring apparatus which concerns on embodiment of this invention. The figure which shows the absorption spectrum of the near infrared light by hemoglobin. The perspective view of the main body shown in FIG. FIG. 3 is a cross-sectional view of the main body shown in FIG. The perspective view of the mouthpiece shown in FIG. FIG. 3 is a partial cross-sectional view of the mouthpiece shown in FIG. A perspective view of a therapeutic mouthpiece similar to the mouthpiece shown in FIG. FIG. 7 is a partial cross-sectional view of the therapeutic maxillary mouthpiece shown in FIG. The figure for demonstrating the upper lip part. Sectional drawing for explaining the upper lip part. The circuit diagram of the irradiation unit shown in FIG. The figure which shows the irradiation pattern of the irradiation unit shown in FIG. The block diagram which shows the structure of the control unit shown in FIG. FIG. 5 is a flowchart showing an example of processing executed by the control unit shown in FIG. The flowchart which made the process of step S1 of FIG. 14 more concrete.

Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 15. FIG. 1 is a diagram showing a schematic configuration of a blood oxygen saturation measuring device (hereinafter, referred to as a device) 100 according to an embodiment of the present invention. The device 100 is used to measure the oxygen saturation (SpO2) in the blood of a living body (human), particularly a sleeping living body, and monitor the decrease in SpO2 that may occur due to sleep apnea. The device 100 includes a main body 10 installed apart from the measurement target (living body) 200 and a mouthpiece 20 detachably attached to the upper and lower jaws of the living body, and the device 100 as a whole functions as a pulse oximeter. To do. The mouthpiece 20 also functions as a therapeutic mouthpiece for suppressing the occurrence of sleep apnea.

FIG. 2 is a diagram showing an absorption spectrum of near-infrared light by hemoglobin. The pulse oximeter utilizes the fact that the light absorption characteristics differ between when the hemoglobin in the blood contains oxygen (oxidized hemoglobin HbO2) and when it does not contain oxygen (reduced hemoglobin Hb), and the pulse oximeter has two or more different wavelengths. It is a device that measures SpO2 from the transmittance of light when a living body is transmitted. The device 100 uses light having two or more different wavelengths from light in a wavelength region (window of the living body) that easily transmits the living body.

Conventionally, in a pulse oximeter, light having a wavelength in the near infrared region such as 780 nm, 805 nm, and 830 nm as shown in FIG. 2 is used. By the way, an imaging sensor used in a general RGB camera can detect light having a wavelength up to about 1100 nm, but in order to prevent the color balance from being lost due to the mixture of visible light and infrared light, An infrared cut filter is used in a normal RGB camera. Therefore, by using an RGB camera from which the infrared cut filter has been removed, it is possible to detect light having a wavelength in the near infrared region.

FIG. 3 is a perspective view of the main body 10. The main body 10 includes a housing 11 having a substantially light bulb shape. The housing 11 has a conductive base portion 12 on which a screw portion 12a is formed at one end. The screw portion 12a is screwed into, for example, the socket 302 at the tip of the stand 301 attached to the wall surface 300, and power is supplied to the main body 10 via the base portion 12. The stand 301 has a flexible movable portion 303, and the orientation of the main body 10 can be adjusted via the movable portion 303. The stand 301 may be a ceiling-mounted type, a self-standing type, a clamp type, or the like, in addition to the wall-mounted type, and a shape that is easy to install on the bedside is suitable. A cover 13 made of a translucent resin material is attached to the other end of the housing 11.

FIG. 4 is a cross-sectional view of the main body 10. As shown in the figure, a camera 15 that receives light emitted from an LED (light emitting diode) described later, a white LED 16, and a control unit 17 that controls the operation of the camera 15 are arranged in the housing 11. , Power is supplied to these from the outside via a base 12 and a cable (not shown). The camera 15 is connected to the control unit 17 via a cable (not shown) or the like.

The camera 15 detects the amount of light received and transmits a signal corresponding to the amount of light to the control unit 17. Further, the camera 15 recognizes the face of the measurement target 200, identifies the position (orientation) of the upper jaw, and transmits the information to the control unit 17. As the camera 15, for example, a normal RGB camera having an optical zoom function of about 5 to 10 times is used with the infrared cut filter removed. As shown in FIG. 4, the camera 15 is arranged in the center of the main body 10 so that the lens portion (light receiving surface) is parallel to the surface of the cover 13. As shown in FIG. 4, the camera 15 has a light receiving surface fixed to the cover 13, and the main body 15a moves in the length direction (indicated by an arrow) of the housing 11 along the rail 11a provided in the housing 11. It is possible, which allows the magnification to be adjusted as appropriate.

The white LED 16 is composed of, for example, a high-brightness white LED. The white LED 16 is arranged in the circumferential direction of the housing 11 so that the irradiation surface is parallel to the surface of the cover 13. Since the white LED 16 is not directly related to the measurement of SpO2, the main body 10 does not necessarily have to be provided with the white LED 16. Therefore, the function as lighting is unnecessary, and the shape of the main body 10 is not limited to the shape of a light bulb.

FIG. 5 is a perspective view of the mouthpiece 20 of FIG. The mouthpiece 20 is composed of a maxillary mouthpiece 20U detachably attached to the upper jaw of the measurement target 200 and a mandibular mouthpiece 20L detachably attached to the lower jaw of the measurement target 200. The mandibular mouthpiece 20L has mountain-shaped protrusions 22 protruding from both the left and right sides toward the upper jaw. The maxillary mouthpiece 20U has a protrusion receiver 23 for sliding contact of the protrusion 22 of the mandibular mouthpiece 20L along the movement of the lower jaw with respect to the upper jaw of the measurement target 200. As shown in FIG. 5, the protrusion receiver 23 is composed of a tubular wall having a substantially isosceles trapezoidal shape when viewed from above.

As shown in FIG. 5, the protrusion 22 and the protrusion receiver 23 are arranged so as to restrict the lower jaw of the measurement target 200 to the forward position. The protrusion 22 and the protrusion receiver 23 are made of a resin having higher strength than the mouthpiece body. When the mouthpiece 20 is attached to the upper and lower jaws, the lower jaw is always restricted to the forward position during sleep to secure the airway. Therefore, the mouthpiece 20 is a treatment for suppressing the occurrence of sleep apnea. It also functions as a mouthpiece for sleep apnea. Since the function as a therapeutic mouthpiece is not directly related to the measurement of SpO2, the mouthpiece 20 does not necessarily have to include the mandibular mouthpiece 20L.

FIG. 6 is a partial cross-sectional view of the maxillary mouthpiece 20U. The main body of the maxillary mouthpiece 20U is made of, for example, a transparent thermoplastic resin, and an orthodontic mouthpiece having a thickness of about 0.5 to 0.8 mm can be used. In manufacturing the maxillary mouthpiece 20U, first, the first layer (inner layer) 20a of the maxillary mouthpiece 20U is molded with a transparent thermoplastic resin. Next, the protrusion receiver 23 and the irradiation unit 24UNT are attached to the upper lip side of the first layer 20a. Finally, a second layer (outer layer) 20b is formed of resin on the first layer 20a, whereby, as shown in FIG. 6, between the first layer 20a and the second layer 20b of the resin. The protrusion receiver 23 and the irradiation unit 24UNT are inserted. The protrusion receiver 23 and the irradiation unit 24UNT are completely waterproofed by the integrated first layer 20a and second layer 20b.

As shown in FIGS. 5 and 6, the irradiation unit 24UNT includes a button type battery 24BB, a printed circuit board 24PCB, an LED 24, a switch 24SW for switching the on / off of the LED 24, and an irradiation control device 24CTL for controlling the turning on / off of the LED 24. Have. The printed circuit board 24PCB has a circular shape having the same size as the button-type battery 24BB, is connected to the button-type battery 24BB via a cable (not shown) or the like, and is arranged on the button-type battery 24BB (upper lip side). A switch 24SW and an irradiation control device 24CTL are mounted on the printed circuit board 24PCB. The button type battery 24BB and the printed circuit board 24PCB are arranged inside the protrusion receiver 23. The LED 24 is arranged in front of the upper lip side of the maxillary mouthpiece 20U, and is connected to the printed circuit board 24 PCB by the lead wire 24LW. The switch 24SW is pressed via a flexible resin (second layer 20b of the maxillary mouthpiece 20U).

As shown in FIG. 5, the LED 24 has a plurality of LEDs 24a, 24b, 24c. The wavelengths λa, λb, λc of the light emitted by the LEDs 24a, 24b, 24c are, for example, 780 nm, 805 nm, and 830 nm (see FIG. 2). The irradiation intensity INT0 of the light emitted by the LEDs 24a, 24b, 24c is constant. By setting three types of wavelengths λa, λb, and λc that are different from each other as the wavelength of the light emitted by the LED 24, the relational expression obtained from the measurement result for each wavelength increases as compared with the case of the two types. Therefore, the accuracy when calculating the% concentrations [HbO2] and [Hb] of oxidized hemoglobin HbO2 and reduced hemoglobin Hb can be improved, and the measurement accuracy of SpO2 can be improved. Since SpO2 can be measured if the LED 24 can irradiate light having at least two kinds of wavelengths, only two of the LEDs 24a and 24c may be used.

FIG. 7 is a perspective view of the therapeutic mouthpiece 20'similar to the mouthpiece 20, and FIG. 8 is a partial cross-sectional view of the therapeutic maxillary mouthpiece 20U'. When the device 100 (pulse oximeter) is not used for a long period of time and only the mouthpiece is continuously used for treatment, the therapeutic mouthpiece 20'as shown in FIGS. 7 and 8 is used. As shown in FIGS. 7 and 8, the therapeutic maxillary mouthpiece 20U'of the therapeutic mouthpiece 20'does not have an irradiation unit 24UNT. Inside the protrusion receiver 23, a treatment attachment 25 having a substantially trapezoidal columnar shape is arranged in place of the button-type battery 24BB, the printed circuit board 24PCB, the switch 24SW, and the irradiation control device 24CTL of the irradiation unit 24UNT. The therapeutic attachment 25 is made of a resin having a strength higher than that of the mouthpiece body, similar to the protrusion receiver 23. Since the therapeutic maxillary mouthpiece 20U'uses the therapeutic attachment 25, it is not necessary to insert a battery or the like into the oral cavity, and the strength of the protrusion receiver 23 can be increased.

9 and 10 are diagrams for explaining the upper lip portion. In the present specification, as shown by diagonal lines in FIG. 9, the portion between the upper lip and the nose is referred to as “upper lip portion”. As shown in FIG. 10, there are maxillary teeth and gums on the back side of the upper lip, and the upper lip is thinner than fingers and the like. Therefore, light can be easily transmitted to the upper lip portion. In addition, blood vessels such as the superior labial artery and capillaries run in the upper lip. On the oral side of the upper lip of the measurement target 200, the irradiation surface of the LED 24 of the maxillary mouthpiece 20U attached to the upper jaw of the measurement target 200 is located.

The light emitted by the LED 24 of the maxillary mouthpiece 20U passes through the upper lip of the measurement target 200 and is received by the camera 15 of the main body 10. In the main body 10, the light receiving surface of the camera 15 of the main body 10 faces the irradiation surface of the LED 24 of the maxillary mouthpiece 20U via the movable portion 303 (FIG. 1), that is, on the upper lip of the measurement target 200. The orientation is adjusted to face.

In the oral cavity of the measurement target 200, the light emitted by the LED 24 of the maxillary mouthpiece 20U is incident on the upper lip from the mucous membrane on the oral side of the measurement target 200. Light incident on the upper lip of the measurement target 200 is scattered inside the body of the measurement target 200, and is absorbed by tissues other than oxidized hemoglobin HbO2, reduced hemoglobin Hb, and blood in the blood, and is transmitted through the upper lip of the measurement target 200. Then, a part of the light that is not lost due to scattering or absorption reaches the camera 15 of the main body 10 (FIG. 1) and is received. Since the mucosa has no stratum corneum or the stratum corneum is extremely thin, specular reflection is unlikely to occur on the mucosal surface. Therefore, most of the light emitted from the oral cavity side is incident on the upper lip without specular reflection on the mucosal surface, so that SpO2 measurement with high accuracy is possible.

For very short periods of time, such as the pulsating cycle, the proportion of light lost by reflection, scattering, and absorption by tissues other than blood is fairly constant. That is, the amount of change ΔA of the absorbance A measured in a pulsation cycle of about 1 second corresponds to the change in the amount of absorbance due to hemoglobin (oxidized hemoglobin HbO2 and reduced hemoglobin Hb) in the blood flowing through the upper lip of the measurement target 200. Assuming that the extinction coefficients of oxidized hemoglobin HbO2 and reduced hemoglobin Hb are εHbO2 and εHb, respectively, the amount of change ΔA of the absorbance A is expressed by the following equation (i) according to Lambert-Beer's law.
ΔA = εHbO2 × [HbO2] + εHb × [Hb] ・ ・ ・ (i)

The irradiation time T of the light of each wavelength λ (λa, λb, λc) by the LED 24 of the upper jaw mouthpiece 20U is set to about 1 second corresponding to the pulsation cycle, and the camera 15 of the main body 10 is irradiated with the light of each wavelength λ. By measuring the maximum light receiving intensity INTMAX and the minimum light receiving intensity INTMIN of the light received by, the amount of change ΔA of the absorbance A can be calculated by the following equation (ii).
ΔA = log (INTMIN / INTMAX) ・ ・ ・ (ii)

Therefore, the concentrations [HbO2] and [Hb] of oxidized hemoglobin HbO2 and reduced hemoglobin Hb are calculated based on three (or any two) simultaneous equations obtained from the measurement results at each wavelength λa, λb, and λc. , SpO2 of the measurement target 200 can be calculated by the following equation (iii).
SpO2 = [HbO2] / ([HbO2] + [Hb]) ... (iii)

FIG. 11 is a circuit diagram of the irradiation unit 24UNT shown in FIG. 5, and FIG. 12 is a diagram showing an irradiation pattern of the irradiation unit 24UNT. When the switch 24SW of the irradiation unit 24UNT is turned on, the LEDs 24a, 24b, and 24c that irradiate light having wavelengths λa, λb, and λc are turned on and off. As shown in FIG. 12, the LEDs 24a, 24b, 24c are sequentially turned on for 0.5 seconds, and then all the LEDs 24a, 24b, 24c are controlled by the irradiation control device 24CTL so as to be turned off for 1.0 second. To.

FIG. 13 is a block diagram showing the configuration of the control unit 17. A camera 15 is connected to the control unit 17 via a cable (not shown) or the like. The control unit 17 receives a signal from the camera 15 according to the amount of received light. Further, the control unit 17 receives information on the position (orientation) of the upper jaw of the measurement target 200 from the camera 15. The control unit 17 is composed of a computer including an arithmetic processing unit including a CPU, a ROM (memory), a RAM, and other peripheral circuits. As a functional configuration, the control unit 17 has a wavelength determination unit 170 that determines the wavelength of the light received by the camera 15, and each wavelength λ (λa, λb, λc) based on a signal corresponding to the amount of light received by the camera 15. Based on the time change of the light receiving intensity INT (INTa, INTb, INTc) calculated by the intensity calculation unit 171 for calculating the light receiving intensity INT (INTa, INTb, INTc) and the light receiving intensity INT (INTa, INTb, INTc) calculated by the intensity calculation unit 171 of each wavelength λ (λa, λa, Change in absorbance A (Aa, Ab, Ac) of λb, λc) Change in absorbance calculated by the absorbance change calculation unit 172 for calculating ΔA (ΔAa, ΔAb, ΔAc) and change in absorbance 172. It has a blood oxygen saturation calculation unit (SpO2 calculation unit) 173 that calculates SpO2 based on ΔA (ΔAa, ΔAb, ΔAc).

The wavelength determination unit 170 determines the wavelength of the light received by the camera 15 from the spot-off pattern of the light based on the signal corresponding to the amount of light received by the camera 15. As shown in FIG. 12, the LEDs 24a, 24b, 24c that irradiate the light having wavelengths λa, λb, and λc are sequentially lit for 0.5 seconds by the irradiation control device 24CTL, and then all the LEDs 24a, 24b, 24c. Is controlled to turn off for 1.0 second. Therefore, after turning off the light for 1.0 second, it is determined that the wavelength λa is 0 to 0.5 seconds, the wavelength λb is 0.5 to 1.0 seconds, and the wavelength λc is 1.0 to 1.5 seconds. Can be done. Since it is possible to grasp which wavelength of light is being irradiated from the on-off patterns of the LEDs 24a, 24b, and 24c, it is not necessary to provide a bandpass filter or the like on the camera 15.

FIG. 14 is a flowchart showing an example of processing executed by the control unit 17. This process is started when a switch (not shown) is turned on, and is repeatedly executed at predetermined time intervals. First, in step S1, the changes in absorbances Aa, Ab, and Ac when light of each wavelength λa, λb, and λc is irradiated from the irradiation unit 24UNT of the maxillary mouthpiece 20U are calculated.

FIG. 15 is a flowchart that more embodies the process of step S1. As shown in FIG. 15, in step S10, the wavelength determination unit 170 determines whether or not the wavelength of the light received by the camera 15 is the wavelength λa. Step S10 is repeated until affirmed. If step S10 is affirmed, the process proceeds to step S11, and the light receiving intensity INTa is calculated by processing by the intensity calculation unit 171. Next, in step S12, the maximum light receiving intensity INTaMAX and the minimum light receiving intensity INTaMIN at the irradiation time T are determined by the processing by the intensity calculation unit 171. Next, in step S13, the change amount ΔAa of the absorbance Aa is calculated by the processing in the absorbance change amount calculation unit 172.

For the wavelengths λb and λc, the same processing as in the flowchart of FIG. 15 is executed in the same manner as for the wavelengths λa. Next, the process proceeds to step S2 of FIG. 14, and the SpO2 of the measurement target 200 is determined based on the changes in the absorbances Aa, Ab, and Ac of the respective wavelengths λa, λb, and λc by the processing by the SpO2 calculation unit 173. calculate. Next, in step S3, the measurement results of SpO2 are stored in the memory of the control unit 17 in chronological order.

According to this embodiment, the following effects can be obtained.
(1) The blood oxygen saturation measuring device (device) 100 is a device for measuring the oxygen saturation SpO2 in the blood of the measurement target 200, and is a mouse for the upper jaw that is detachably attached to the upper jaw of the measurement target 200. The LED 24 (24a, 24c), which is attached to the piece 20U and the upper jaw mouthpiece 20U and irradiates light of different first and second wavelengths λa, λc (for example, 780 nm, 830 nm), is irradiated by the LED 24. The RGB camera 15 from which the infrared cut filter has been removed that receives the light transmitted through the upper lip of the measurement target 200, the wavelength determination unit 170 that determines the wavelength of the light received by the camera 15, and the light received by the camera 15. Absorption A (Aa, Ac) by the upper lip of the measurement target 200 based on the time change of the light receiving intensity INT calculated by the intensity calculation unit 171 for calculating the light receiving intensity INT (INTa, INTc) and the light receiving intensity INT calculated by the intensity calculation unit 171. The amount of change in absorbance 172 that calculates the amount of change ΔA (ΔAa, ΔAc), the wavelength λa, λc of light determined by the wavelength determination unit 170, and the amount of change in absorbance calculated by the amount of change in absorbance 172. A blood oxygen saturation calculation unit (SpO2 calculation unit) 173 for calculating the oxygen saturation SpO2 in the blood of the measurement target 200 based on ΔA is provided (FIGS. 1, FIGS. 3 to 5, 13).

That is, instead of irradiating the light for SpO2 measurement toward the measurement target 200, the light is radiated from the LED 24 of the maxillary mouthpiece 20U worn by the measurement target 200, so that it does not give a sense of discomfort such as glare during sleep. SpO2 of the measurement target 200 can be measured. In addition, since a normal RGB camera from which the infrared cut filter has been removed is used instead of an infrared camera, the device 100 as a whole can be made highly accurate at low cost by using an RGB camera that is cheaper and more accurate than the infrared camera. can do. Further, since the light emitted by the LED 24 is incident on the upper lip from the mucous membrane on the oral side of the measurement target 200, the loss of light due to reflection is smaller than that when the light is irradiated from the skin side of the measurement target 200, and the accuracy is high. High SpO2 measurement is possible.

(2) The camera 15 and the control unit 17 (wavelength determination unit 170, intensity calculation unit 171, absorbance change calculation unit 172, SpO2 calculation unit 173) are installed apart from the measurement target 200 (FIGS. 1, FIG. 3, Fig. 4). Since the measurement target 200 does not need to be equipped with a large or heavy camera 15 or a control unit, SpO2 can be measured without giving a sense of discomfort to the measurement target 200 during sleep.

(3) The device 100 includes a housing 11 in a main body 10 installed apart from the measurement target 200, and a camera 15 and a control unit 17 (wavelength determination unit 170, intensity calculation unit 171; absorbance change calculation unit 172, The SpO2 calculation unit 173) is stored in the housing 11 (FIGS. 1, 3, and 4). For example, if the housing 11 has a substantially light bulb shape having a base portion 12, electric power can be easily supplied from a general light bulb socket via the base portion 12. Further, if the stand 301 having the bendable movable portion 303 is used, the main body 10 can be easily adjusted in a direction suitable for measurement. Furthermore, by using a stand 301 having a shape that is easy to install on the bedside, such as a wall-mounted type, a ceiling-mounted type, a self-standing type, and a clamp type, the main body 10 can measure the measurement target 200 during sleep. It can be easily placed in a suitable position.

(4) The device 100 further includes an irradiation control device 24CTL that controls the LEDs 24a and 24c to irradiate light of the first and second wavelengths λa and λc in a predetermined point-off pattern, and the wavelength determination unit 170 includes a wavelength determination unit 170. The wavelength of the light received by the camera 15 is determined based on a predetermined pattern (FIGS. 5, 11, and 12). Since it is possible to grasp which wavelength of light is being irradiated from the on / off patterns of the LEDs 24a and 24c, it is not necessary to provide a bandpass filter or the like on the camera 15.

(5) The device 100 further includes a lower jaw mouthpiece 20L that is detachably attached to the lower jaw of the measurement target 200, and the lower jaw mouthpiece 20L has the lower jaw mouthpiece 20L of the lower jaw of the measurement target 200 on both the left and right sides. The upper jaw mouthpiece 20U has a pair of protrusions 22 protruding toward the upper jaw side of the measurement target 200, and the lower jaw mouthpiece 20L is attached to the lower jaw of the measurement target 200 on both the left and right sides. When the upper jaw mouthpiece 20U is attached to the upper jaw of the measurement target 200, the pair of protrusions 22 have a pair of protrusion receivers 23 to be slid along with the movement of the lower jaw with respect to the upper jaw of the measurement target 200. The pair of protrusions 22 and the pair of protrusion receivers 23 are such that when the lower jaw mouthpiece 20L is attached to the lower jaw of the measurement target 200 and the upper jaw mouthpiece 20U is attached to the upper jaw of the measurement target 200, the measurement target 200 Arranged to regulate the lower jaw to the forward position. By attaching the mouthpieces 20U and 20L to the upper and lower jaws of the measurement target 200, the lower jaw is always regulated to the forward position and the airway is secured even during sleep, so that the occurrence of sleep apnea can be suppressed. ..

(6) The first and second wavelengths λa and λc are in the near infrared region and not in the visible light region. Therefore, the measurement target 200 does not visually recognize the turning on and off of the LED 24 through the upper lip portion, and the SpO2 can be measured by irradiating the measurement target 200 with light without disturbing the sleep.

(7) The LED 24 further irradiates light having a third wavelength λb different from the first and second wavelengths λa and λc. As a result, the wavelengths of the light emitted by the LED 24 become three wavelengths of λa, λb, and λc, and the relational expressions obtained from the measurement results for each wavelength increase, and the concentrations of oxidized hemoglobin HbO2 and reduced hemoglobin Hb [HbO2] and [Hb]. ] Can be improved to improve the measurement accuracy of SpO2.

The above description is merely an example, and the present invention is not limited to the above-described embodiments and modifications as long as the features of the present invention are not impaired. The components of the above embodiments and modifications include those that are replaceable and self-explanatory while maintaining the identity of the invention. That is, other forms that can be considered within the scope of the technical idea of the present invention are also included within the scope of the present invention. Moreover, it is also possible to arbitrarily combine one or more of the above-described embodiment and the modified example.

10 main body, 11 housing, 15 camera, 17 control unit, 20 mouthpiece, 20L lower jaw mouthpiece, 20U maxillary mouthpiece, 22 protrusions, 23 protrusion receivers, 24 (24a, 24b, 24c) LED (light emitting diode) , 24CTL irradiation control device, 170 wavelength determination unit, 171 intensity calculation unit, 172 absorption change amount calculation unit, 173 blood oxygen saturation calculation unit (SpO2 calculation unit), 100 blood oxygen saturation measurement unit (device), 200 Measurement target

Claims (6)

It is a blood oxygen saturation measuring device that measures the oxygen saturation in the blood of a living body.
A mouthpiece for the maxilla that is detachably attached to the maxilla of the living body,
An irradiation unit attached to the maxillary mouthpiece and irradiating light of different first and second wavelengths, and an irradiation unit.
The light receiving part of the RGB camera from which the infrared cut filter has been removed, which receives the light irradiated by the irradiation part and transmitted through the upper lip part of the living body, and
A wavelength determination unit that determines the wavelength of the light received by the light receiving unit, and
An intensity calculation unit that calculates the light reception intensity of the light received by the light receiving unit,
An absorbance change amount calculation unit that calculates the amount of change in absorbance by the living body based on the time change of the light receiving intensity calculated by the intensity calculation unit.
Blood oxygen that calculates the oxygen saturation in the blood of the living body based on the wavelength of the light determined by the wavelength determination unit and the change in absorbance calculated by the absorbance change calculation unit. Saturation calculation unit and
A housing for storing the light receiving unit, the wavelength determination unit, the intensity calculation unit, the absorbance change amount calculation unit, and the blood oxygen saturation calculation unit is provided .
Wherein the housing, the member that is fixedly disposed in a room, blood oxygen saturation measuring apparatus wherein the light receiving portion and said Rukoto mounted to face the living body. In the blood oxygen saturation measuring device according to claim 1,
A blood oxygen saturation measuring device, wherein the housing is placed above the head of the living body sleeping indoors and is supported by a wall in the room. In the blood oxygen saturation measuring device according to claim 1 or 2.
Further, an irradiation control unit for controlling the irradiation unit to irradiate light of the first and second wavelengths in a predetermined point-off pattern is provided.
The wavelength determination unit is a blood oxygen saturation measuring device, which determines the wavelength of the light received by the light receiving unit based on the predetermined point-off pattern. In the blood oxygen saturation measuring device according to any one of claims 1 to 3.
A mandibular mouthpiece that is detachably attached to the mandible of the living body is further provided.
The mandibular mouthpiece has a pair of protrusions on both the left and right sides that protrude toward the upper jaw of the living body when the mandibular mouthpiece is attached to the lower jaw of the living body.
In the maxillary mouthpiece, when the mandibular mouthpiece is attached to the lower jaw of the living body on both left and right sides and the maxillary mouthpiece is attached to the upper jaw of the living body, the movement of the lower jaw with respect to the upper jaw of the living body Along the pair of protrusions have a pair of protrusion holders to be slidably contacted.
The pair of protrusions and the pair of protrusion receivers means that when the mandibular mouthpiece is attached to the lower jaw of the living body and the maxillary mouthpiece is attached to the upper jaw of the living body, the lower jaw of the living body is attached. A blood oxygen saturation measuring device characterized in that it is arranged so as to regulate the forward position. In the blood oxygen saturation measuring device according to any one of claims 1 to 4.
A blood oxygen saturation measuring device characterized in that the first and second wavelengths are in the near infrared region. In the blood oxygen saturation measuring device according to any one of claims 1 to 5.
The irradiation unit is a blood oxygen saturation measuring device, which further irradiates light having a third wavelength different from the first and second wavelengths.

Images