JP7395135B2 - blood measuring device - Google Patents

Description

The present invention relates to a blood measuring device that optically measures the amount of components contained in blood inside a part to be measured such as a human body.

There are invasive methods and non-invasive methods as methods for detecting sugar content inside a measurement target site. The invasive method is a method in which blood is collected from, for example, a fingertip of a human body, and the amount of glucose is measured using the blood. The non-invasive method is a method in which the amount of glucose is measured using a sensor placed outside the human body, without collecting blood from the human body. Although invasive methods are generally used to accurately calculate glucose levels, a non-invasive calculation device is desired in order to reduce user pain and improve convenience.

BACKGROUND ART As an example of a device that non-invasively measures the amount of glucose, a device that optically measures the amount of glucose by irradiating the human body with near-infrared light or the like is known.

Furthermore, as an optical glucose measurement device, there is one that detects a difference in the amount of near-infrared light absorbed by glucose. Specifically, in this device, near-infrared light is transmitted through a certain part, and the amount of glucose is measured from the amount of transmitted light (for example, Patent Document 1 and Patent Document 2).

Patent No. 3093871 Patent No. 3692751

However, the devices for measuring the amount of glucose using the non-invasive method described in each of the above-mentioned patent documents have a problem in that the amount of glucose cannot necessarily be accurately measured.

Specifically, in the measurement technique described in Patent Document 1, the amount of glucose is calculated by the glucose oxidase method, so there is a problem that calculation of the amount of glucose is complicated. Further, in the measurement technique described in Patent Document 2, although the amount of glucose is measured by an optical method, it is only possible to determine the possibility of diabetes, and the amount of glucose cannot be measured quantitatively.

The present invention was made in view of these problems, and an object of the present invention is to allow each light beam for calculating the amount of components contained in blood to pass along the same optical axis. An object of the present invention is to provide a blood measuring device that can accurately estimate the amount of components contained in blood.

The blood measuring device of the present invention includes a light emitting section having a first light emitting section that emits a first light beam of a first wavelength, and a second light emitting section that emits a second light beam of a second wavelength; a light-receiving section that receives the first light beam and the second light beam that have passed therethrough; a calculation control section that estimates the amount of components contained in blood based on the received light intensities of the first light beam and the second light beam; and the light-emitting section. A side surface of one side is formed of a light emitting unit housing part in which the light receiving part is stored, a light receiving part housing part in which the light receiving part is stored, and an inclined surface formed in the vicinity of the light emitting part housing part and the light receiving part housing part. The first contact portion includes a first contact portion, a second contact portion constituting the other side surface, and a pressing portion protruding outward from the inclined surface, and the first contact portion The second contact portion is a curved surface that is recessed inward so that a finger can be easily inserted into the second contact portion, and the second contact portion is a curved surface that is recessed inward so that a finger can be easily inserted into the second contact portion. When measuring the amount of contained components, the first contact part contacts a user's finger, the second contact part contacts another finger of the user, and the pressing part contacts the user's finger. The first contact portion contacts the user's thumb, and the second contact portion contacts the user's index finger .

According to the blood measuring device of the present invention, it is possible to provide a blood measuring device that can accurately estimate the amount of components contained in blood.

1 is a diagram showing a blood measuring device according to an embodiment of the present invention, and (A) and (B) are perspective views showing the blood measuring device. 1 is a conceptual diagram showing a connection configuration of a blood measuring device according to an embodiment of the present invention. FIG. 1 is a perspective view showing an actuator of a blood measuring device according to an embodiment of the present invention. FIG. 1 is an exploded perspective view showing an actuator of a blood measuring device according to an embodiment of the present invention. 1A and 1B are top views showing a method of measuring a glucose amount using a blood measuring device according to an embodiment of the present invention, and sequentially showing a method of applying a blood measuring device to a finger web. FIG. 2 is a cross-sectional view showing a method of detecting a glucose amount using a blood measuring device according to an embodiment of the present invention, and showing a situation in which the blood measuring device is applied to a finger web. FIG. 3 is a diagram showing a glucose amount calculation method according to an embodiment of the present invention, and (A), (B), (C), and (D) are diagrams in which the light emitting part and the light receiving part are connected while moving the light emitting point. FIG. 3 is a side view showing a situation in which measurement is performed while approaching the object. 1 is a diagram showing a glucose amount calculation method according to an embodiment of the present invention, (A) is a schematic diagram showing a finger web, (B) is a graph showing a result of measuring glucose amount with a fingertip, and (C ) is a graph showing the results of measuring the amount of glucose using a finger web. FIG. 7 is a cross-sectional view showing a method of detecting a glucose amount using a blood measuring device according to another embodiment of the present invention, and showing a situation in which the blood measuring device is applied to a finger web.

Hereinafter, a blood measuring device 10 according to an embodiment of the present invention will be described in detail based on the drawings. In the following description, the same reference numerals will be used for the same members in principle, and repeated description will be omitted. In this embodiment, the amount of glucose is employed as an example of the amount of components contained in blood measured by the blood measuring device 10.

With reference to FIG. 1, the appearance etc. of the blood measuring device 10 of this embodiment will be described. FIG. 1(A) is a perspective view of the blood measuring device 10 seen from the upper front, and FIG. 1(B) is a perspective view of the blood measuring device 10 seen from the lower front.

Referring to FIGS. 1(A) and 1(B), the design portion of blood measuring device 10 is made of synthetic resin or the like. Further, the blood measuring device 10 as a whole has a substantially rectangular parallelepiped shape with the longitudinal direction along the front-rear direction. When the blood measuring device 10 is viewed from above, the central portion of the front end protrudes forward. Further, the size and weight of the blood measuring device 10 are such that a user who uses the blood measuring device 10 to measure the amount of glucose can grasp it with one hand. Here, the amount of glucose refers to the amount of glucose in blood or interstitium. Further, the amount of glucose is sometimes referred to as blood sugar level or the like.

An actuator housing section 30 is formed at the bottom of the blood measuring device 10. The actuator housing section 30 houses a mechanism for displacing the light emitting section 11, which will be described later, and its configuration will be described later. The second pressing portion 27 is formed by protruding the vicinity of the front central portion of the actuator storage portion 30 toward the front. The second pressing section 27 presses a specific part of the human body when measuring the amount of glucose using the blood measuring device 10, and the details will be described later with reference to FIG.

An upper plate portion 20 is formed at the upper end of the blood measuring device 10. The first pressing portion 25 is formed by protruding the vicinity of the front central portion of the upper plate portion 20 toward the front. The first pressing section 25 presses a specific part of the human body when measuring the amount of glucose using the blood measuring device 10, and the details thereof will be described later with reference to FIG. 6.

Referring to FIG. 1(A), a contact portion 28 is formed at the upper right side of the blood measuring device 10. The contact portion 28 may be a flat surface or may be a curved surface that is recessed inward so that the user's finger can easily fit therein. The contact portion 28 is a region that, for example, the user's thumb comes into contact with when calculating the amount of glucose using the blood measuring device 10.

A clamping portion 232 is formed by partially cutting out the front end portion of the contact portion 28 . The width of the holding portion 232 in the vertical direction is such that a finger web, which will be described later, can be inserted therein. Further, the rear end of the holding part 232 is arranged behind the opening 41 through which the light beam for measurement passes. Therefore, by bringing the peripheral edge of the finger web, which is the part to be measured, into contact with the rear end of the holding part 232, the finger web can be reliably placed in the opening 41, and the light beam passing through the opening 41 can be directed onto the finger web. It can be transmitted reliably.

Referring to FIG. 1(B), a contact portion 29 is formed at the upper left side of the blood measuring device 10. As shown in FIG. The contact portion 29 may be a flat surface or may be a curved surface that is recessed toward the inside so that the user's finger can easily fit therein. The contact part 29 is a part that, for example, the user's index finger comes into contact with when calculating the glucose amount using the blood measuring device 10 .

The holding portion 231 is formed by partially cutting out the front end portion of the contact portion 29 . The specific shape of the clamping part 231 is the same as that of the clamping part 232 described above.

Referring to FIG. 1(A), a light emitting unit housing portion 31 is formed near the front end of the upper surface of the actuator housing portion 30. As shown in FIG. Furthermore, the light emitting unit housing section 31 is disposed between the holding section 231 and the holding section 232 in the left-right direction. The light emitting unit housing portion 31 is a portion where the light emitting unit 11, which will be described later, is arranged. Furthermore, a sloped surface 33 that slopes downward toward the front is formed at the front portion of the light emitting unit housing portion 31 . By forming the inclined surface 33, the finger web can be guided along the inclined surface 33 to the holding parts 231 and 232 when measuring the amount of glucose. Further, an opening 41 is formed by opening the upper surface of the light emitting unit housing section 31 .

Referring to FIG. 1(B), a light receiving portion housing portion 32 is formed that protrudes downward from the front of the lower surface of the upper plate portion 20. As shown in FIG. The light receiving unit housing portion 32 is a portion where a light receiving unit 19, which will be described later, is stored. Furthermore, an opening 42 is formed on the lower surface of the light receiving unit housing portion 32 through which a light beam used for measuring the amount of glucose passes.

FIG. 2 is a conceptual diagram showing the basic configuration of the blood measuring device 10. Referring to FIG. 2, blood measuring device 10 includes a light emitting unit 11 that emits a light beam used for measurement, a lens 14 that is an optical element that guides the light beam emitted from light emitting unit 11 to a part to be measured 18, and a part to be measured. A light receiving section 19 that receives the light beam transmitted through the measurement site 18, an arithmetic control section 17 that calculates the amount of glucose based on the output of the light receiving section 19, a storage section 13, a display section 15, an operation input section 12, A temperature measuring section 21 is provided. Here, instead of the lens 14, a pinhole can be used to focus the light beam.

The function of the blood measuring device 10 is to measure the amount of glucose in the human body by a non-invasive method by transmitting a light beam through the human body, which is the part to be measured.

The light emitting unit 11 emits light of a predetermined wavelength in order to measure the amount of glucose. The light emitting section 11 includes a first light emitting section 111, a second light emitting section 112, and a third light emitting section 113 that emit light beams with different wavelengths. The first light emitting section 111, the second light emitting section 112, and the third light emitting section 113 each include a light emitting diode. For example, the wavelength of the first light beam emitted from the first light emitting section 111 is 1310 nm, the wavelength of the second light beam emitted from the second light emitting section 112 is 1450 nm, and the wavelength of the second light beam emitted from the third light emitting section 113 is 1310 nm. The wavelength of the three light beams is 1550 nm.

The first light ray is a light ray that is not absorbed by components in the living body, and the second and third light rays are light rays that are absorbed by glucose, protein, and water in the living body. By measuring the optical path length of the optical axis 22 with the first light beam, it is possible to measure the influence of the optical path length on the absorption rate of each light beam, eliminate the influence of the optical path length, and accurately calculate the amount of glucose. be able to.

The actuator 16 moves the light emitting section 11 in the left and right direction. By moving the light emitting section 11, any one of the light emitting points of the first light emitting section 111, the second light emitting section 112, and the third light emitting section 113 can be arranged on the same optical axis 22. Here, a case is shown in which the light emitting point of the second light emitting section 112 is arranged on the optical axis 22.

Furthermore, the actuator 16 moves either or both of the light emitting section 11 and the light receiving section 19 in the vertical direction. For example, the actuator 16 separates the light receiving section 19 from the light emitting section 11 when the blood measuring device 10 is not measuring the amount of glucose. On the other hand, the actuator 16 causes the light receiving section 19 and the light emitting section 11 to approach each other when the blood measuring device 10 measures the amount of glucose. An example of a specific configuration of the actuator 16 will be described later with reference to FIGS. 3 and 4.

In this embodiment, the first light beam, the second light beam, and the third light beam are irradiated from the light emitting section 11 to the light receiving section 19 along the same optical axis 22. In other words, the first, second, and third light rays have the same propagation path and propagation length inside the measurement target site 18 .

By sharing the optical axis 22 with each light beam as described above, the amount of glucose can be accurately measured. Specifically, according to Lambert-Beer's law, the amount of glucose is calculated using the following equation 1.
Formula 1: C=-log ₁₀ (I/I ₀ )/(0.434×μ _a ×r)
In the above equation 1, C is the amount of glucose, I is the output light power, I0 is the incident light power, μ _a is the skin absorption coefficient, and r is the optical path length.

In this embodiment, the first, second, and third light rays share the optical axis 22 to make the optical path length r the same, thereby reducing the number of unknowns to be calculated and accurately and easily measuring glucose. The quantity C can be determined.

The lens 14 converts the first light beam, second light beam, and third light beam emitted from the first light emitting section 111, the second light emitting section 112, and the third light emitting section 113 to the object to be measured by its refraction and diffraction effects. Lead to part 18.

The measurement site 18 is a site where the amount of glucose is measured by the blood measurement device 10 of this embodiment. Specifically, the part to be measured 18 may be a fingertip, an earlobe, a finger web, or the like. As will be described later, the finger web that contains a small amount of fat, has small individual differences in thickness, and does not have large blood vessels is suitable as the measurement site 18.

The light-receiving section 19 is a semiconductor element made of, for example, a photodiode, and is formed with a light-receiving section that receives the first, second, and third light beams that have passed through the measurement site 18 and detects their intensity. The light receiving unit 19 transmits signals corresponding to the received light intensities of the first light beam, the second light beam, and the third light beam to the calculation control unit 17.

The storage unit 13 is a semiconductor storage device such as a RAM or ROM, and stores calculation formulas, parameters, estimation results, programs for executing the glucose amount calculation method, etc. for calculating the glucose amount from the output value of the light receiving unit 19. I remember.

The operation input unit 12 is a part through which a user gives instructions to the calculation control unit 17, and is composed of switches, a touch panel, and the like.

The temperature measurement unit 21 is a part that measures the user's body temperature by coming into contact with the user's body.

The arithmetic control section 17 is composed of a CPU, performs various arithmetic operations, and controls the operation of each part constituting the blood measuring device 10. Specifically, the calculation control unit 17 irradiates the first light beam, the second light beam, and the third light beam from the first light emission section 111 , the second light emission section 112 , and the third light emission section 113 of the light emission section 11 . Further, the calculation control unit 17 estimates the amount of glucose using a conversion formula based on the electrical signals input from the light receiving unit 19, the temperature measuring unit 21, and the like. Further, the calculation control unit 17 may display the calculated glucose amount on the display unit 15. For example, by displaying the glucose amount on the display unit 15, which is a liquid crystal monitor, the user of the blood measuring device 10 can know changes in his or her own glucose amount in real time. Further, during measurement, in order to arrange the light emitting points of each light emitting section along the optical axis 22, the calculation control section 17 operates the actuator 16 to move the light emitting section 11 and the light receiving section 19.

The actuator 16 will be described in detail with reference to FIGS. 3 and 4. FIG. 3 is a perspective view showing the actuator 16, and FIG. 4 is an exploded perspective view showing the actuator 16 exploded in the vertical direction.

Referring to FIG. 3, the actuator 16 mainly includes a housing 34, a lid 35, a holder 36, a motor 37, a rotating shaft 38, and a threaded portion 39. The actuator 16 moves each light emitting point of the first light emitting part 111, the second light emitting part 112, or the third light emitting part 113 by moving the light emitting part 11 in the left and right direction based on the instruction from the above-mentioned calculation control part 17. , are arranged on the optical axis 22. Note that the light receiving point of the light receiving section 19 is also arranged on the optical axis 22 .

The specific operation of the actuator 16 is such that the motor 37 rotates the rotary shaft 38 based on the instruction from the arithmetic control section 17 described above, and the threaded portion 39 that is screwed or engaged with the rotary shaft 38 rotates in the left-right direction. Move to. When the threaded part 39 moves in the left-right direction, the holder 36 on which the light-emitting part 11 is placed also moves in the left-right direction. Thereby, the light emitting points of the first light emitting section 111, the second light emitting section 112, or the third light emitting section 113 can be arranged along the optical axis 22.

Each part of the actuator 16 will be explained with reference to FIG. 4. The housing 34 is a generally box-shaped portion with an open top. A motor 37, a rotating shaft 38, and a threaded portion 39 are built into the housing 34.

Inside the housing 34 , a portion of the rotating shaft 38 led out from the motor 37 is disposed in a threaded portion 39 . A thread groove is formed on the side surface of the rotating shaft 38. The threaded portion 39 is screwed into or engaged with a threaded groove of the rotating shaft 38, and thus moves in the left-right direction as the rotating shaft 38 rotates. A hole 44 is formed in the upper surface of the threaded portion 39 . The hole 44 is arranged below the opening 40, which will be described later.

The lid portion 35 is a plate-shaped member that closes the upper opening of the housing 34 . An elongated opening 40 is formed in the lid portion 35 along the left-right direction.

The holder 36 has a substantially rectangular parallelepiped shape, and the light emitting section 11 is disposed on the upper surface thereof. Further, the holder 36 is formed with a substantially rod-shaped protrusion 43 that protrudes downward. The protrusion 43 passes through the opening 40 and is inserted into the hole 44 .

With the actuator 16 configured as described above, when the motor 37 rotates the rotating shaft 38 in one direction based on instructions from the arithmetic control unit 17, this rotation causes the threaded part 39 to move toward the right. Along with this movement, the holder 36 and the light emitting section 11 move toward the right. Conversely, when the motor 37 rotates the rotary shaft 38 in the opposite direction based on the instruction from the arithmetic control unit 17, the threaded part 39 moves toward the left due to the rotation, and the holder 36 and The light emitting section 11 moves toward the left. By doing so, any one of the light emitting points of the first light emitting section 111 , the second light emitting section 112 , and the third light emitting section 113 can be arranged along the same optical axis 22 . On the other hand, the position of the light receiving section 19 is always fixed in the front, rear, left and right directions, and is arranged along the axis of the optical axis 22.

Next, based on FIGS. 5 to 7 and with reference to FIGS. 1 to 4 described above, a specific method for measuring a user's glucose amount using the blood measuring device 10 having the above configuration will be explained. .

Referring to FIG. 5, first, blood measuring device 10 is set at the user's site to be measured. 5(A) and 5(B) are diagrams sequentially showing the situation in which the blood measuring device 10 is set on the finger web, which is the site to be measured. Here, a finger web formed between the thumb and index finger of the left hand is used as the site for measuring the amount of glucose. Therefore, the user easily operates the blood measuring device 10 with his or her right hand.

Referring to FIG. 5(A), the blood measuring device 10 is fitted from the index finger side portion of the finger web. Specifically, the clamping part 232 and the clamping part 231 of the blood measuring device 10 are slid from the index finger side portion of the finger web. At this time, the user stretches the finger web by spreading the thumb and index finger apart.

Referring to FIG. 5(B), next, with the finger web being held between the holding parts 231 and 232, the blood measuring device 10 is pushed leftward and moved toward the thumb side. Here, the blood measuring device 10 is slid until the distal end of the blood measuring device 10 reaches the base of the thumb or the vicinity thereof.

Here, the ends of the finger webs are in contact with the rear ends of the clamping parts 231 and 232. By doing so, the light emitting section 11 and the light receiving section 19 can be arranged in a portion overlapping with the finger web. In this state, each light beam emitted from the light emitting section 11 passes through the finger web and reaches the light receiving section 19 .

Here, the base of the thumb or the vicinity thereof may be brought into contact with the contact portion 28 of the blood measuring device 10. Alternatively, the base of the index finger or its vicinity may be brought into contact with the contact portion 29 of the blood measuring device 10. This allows the angle at which the thumb and forefinger open to be greater than a certain level, thereby preventing the finger web from bending. Furthermore, when measuring the amount of glucose, the angle at which the thumb and index finger open can be made uniform, and the thickness of the finger web can be made constant.

FIG. 6 is a cross-sectional view taken along the section line AA in FIG. 5(B). Referring to this figure, the first pressing section 25 of the blood measuring device 10 presses the adductor pollicis muscle 24 of the hand or the vicinity thereof toward the front. Further, the second pressing portion 27 of the blood measuring device 10 presses the mother and baby bulb 26 or the vicinity thereof toward the front. By doing so, the relative positions of the light emitting section 11 and the light receiving section 19 and the finger web can be set to a predetermined positional relationship, and the amount of glucose can be calculated more accurately using the light beam that passes through the finger web. be able to.

With reference to FIG. 7, the matter of irradiating each light beam while displacing the light emitting section 11 will be described. 7(A) shows the light emitting unit 11 before emitting the light beam, FIG. 7(B) shows the situation where the second light beam is emitted from the second light emitting unit 112, and FIG. FIG. 7D shows a situation in which the first light beam is emitted from the third light emitting part 111, and FIG. 7D shows a situation in which the third light beam is emitted from the third light emitting part 113. Here, the second light emitting section 112, the first light emitting section 111, and the third light emitting section 113 emit light along the optical axis 22 in this order, but this order can be changed.

Referring to FIG. 7(A), the light emitting section 11 and the light receiving section 19 are arranged so as to sandwich the measured part 18, which is a finger web, in the vertical direction. The actuator 16 moves either or both of the light emitting section 11 and the light receiving section 19 in the vertical direction, thereby shortening the distance between the light emitting section 11 and the light receiving section 19 in the vertical direction.

Here, the actuator 16 moves the light receiving section 19 downward based on the instruction from the arithmetic control section 17 described above. For example, referring to FIG. 1(A), by moving the light receiving section storage section 32 downward, the light receiving section 19 built in the light receiving section storage section 32 can be lowered. Here, the finger web may have a constant thickness by being sandwiched between the light emitting section housing section 31 and the light receiving section housing section 32, or may not be sandwiched between them.

Referring to FIG. 7(B), when emitting the second light beam from the second light emitting section 112, first, the arithmetic control section 17 causes the light emitting point of the second light emitting section 112 to align with the optical axis 2 by the actuator 16. The light emitting unit 11 is moved so that it overlaps with the . When the light emitting point of the second light emitting section 112 overlaps with the optical axis 22, the calculation control section 17 causes the second light emitting section 112 to emit a second light beam. The emitted second light beam travels along the optical axis 22 and, after passing through the measurement site 18 , is irradiated onto the light receiving section 19 . An electrical signal indicating the intensity of the second light beam received by the light receiving section 19 is transmitted to the calculation control section 17 .

Referring to FIG. 7C, next, the calculation control unit 17 moves the light emitting unit 11 to the right using the actuator 16, so that the light emitting point of the first light emitting unit 111 overlaps the optical axis 22. When the light emitting point of the first light emitting section 111 overlaps with the optical axis 22, the calculation control section 17 causes the first light emitting section 111 to emit a first light beam. The emitted first light beam travels along the optical axis 22 and is irradiated onto the light receiving section 19 after passing through the measurement target part 18 . An electrical signal indicating the intensity of the first light beam received by the light receiving section 19 is transmitted to the calculation control section 17 .

Referring to FIG. 7(D), next, the arithmetic control unit 17 moves the light emitting unit 11 to the left using the actuator 16, thereby causing the light emitting point of the third light emitting unit 113 to overlap with the optical axis 22. When the light emitting point of the third light emitting section 113 overlaps with the optical axis 22, the calculation control section 17 causes the third light emitting section 113 to emit a third light beam. The emitted third light beam travels along the optical axis 22 and is irradiated onto the light receiving section 19 after passing through the measurement target part 18 . An electrical signal indicating the intensity of the third light beam received by the light receiving section 19 is transmitted to the calculation control section 17.

Furthermore, based on instructions from the calculation control section 17 , the temperature measurement section 21 measures the user's body temperature, and an electrical signal indicating the body temperature is transmitted to the calculation control section 17 .

After measuring the received light intensity of the first light beam, second light beam, and third light beam by the method described above, the amount of glucose of the user is calculated based on the received light intensity of each light beam, body temperature, and the like. As this calculation method, for example, a statistical method can be used. As an example, a multiple regression curve is created by statistical analysis using the user's blood glucose amount, the received light intensity of each light beam, body temperature, and the like. Then, the estimated glucose amount is calculated from the received light intensity of each light beam and body temperature using the regression curve.

With reference to FIG. 8, the suitability of a finger web as a measurement site to which each light beam is irradiated in order to estimate the amount of glucose will be described. FIG. 8(A) is a schematic diagram showing a user's hand, FIG. 8(B) is a graph showing an error grid when estimating glucose amount using a fingertip, and FIG. 8(C) is a graph showing an error grid using a finger web. 2 is a graph showing an error grid for estimating the amount of glucose. In FIGS. 8(B) and 8(C), the horizontal axis indicates the amount of blood glucose collected, and the vertical axis indicates the estimated glucose amount measured by the method according to the present embodiment.

Referring to FIG. 8(A), a finger web is a membrane-like region formed between fingers of the human body. Here, a finger web formed between other fingers can also be employed as the part to be measured.

Referring to FIG. 8(B), dots indicating measurement results are distributed away from the reference line indicated by a broken line. The reason for this is thought to be that the thickness of the fingertip varies greatly among individuals, which causes the optical path length to vary, and that the thick blood vessels present in the fingertip have an adverse effect.

On the other hand, referring to FIG. 8C, dots indicating measurement results are distributed near the reference line indicated by a broken line. The reason for this is that the finger web has a thickness of about 2 mm to 4 mm, has small differences between individuals, has an extremely low fat content, and has no large blood vessels inside, so it can be used to measure capillaries and the dermis. It is from. Furthermore, when a finger web is employed as the measurement target site, the optical path length can be shortened, and the glucose amount can be measured with low output light.

With reference to Table 1, the suitability of the finger web as a measurement site from the viewpoint of fat content will be explained.

Table 1 shows specimen 1 containing fat (epidermis 0.2 mm, dermis 0.8 mm, fat 1.5 mm) and body specimen 2 not containing fat (epidermis 0.2 mm, dermis 0.8 mm, no fat). The results of measuring the transmittance of the first light beam, the second light beam, and the third light beam are shown. To give an example, specimen 1 is a fat human fingertip, and specimen 2 is a finger web.

The simulation conditions here are that the number of rays is 5000, the number of scattering is 1000 times per ray, the diameter of light incident on the skin is 1.5 mm, and the diameter of the light receiving surface is 3 mm or 1 mm.

As shown in Table 1, for the first light beam having a wavelength of 1310 nm, the transmittance of specimen 2 is 3.4 times that of specimen 1. Further, in the second light beam having a wavelength of 1450 nm, the transmittance of the specimen 2 is 6.2 times that of the specimen 1. Furthermore, in the third light beam having a wavelength of 1550 nm, the transmittance of specimen 2 is 3.5 times that of specimen 1.

From the above, the specimen 1, which is a fingertip, for example, has a low transmittance of the first to third light rays, and is therefore not suitable as a site for measuring the amount of glucose. Furthermore, considering that the fat content varies greatly among individuals, it is clear that the amount of fat affects the transmittance, making it difficult to estimate the amount of glucose.

On the other hand, specimen 2, which is a finger web, has an extremely low fat content, so it allows the first, second, and third light rays to pass through it well, and the amount of glucose can be accurately determined based on the intensity of each transmitted light ray. It can be estimated that Further, even if the user is obese, the fat contained in the finger web will not increase significantly. Therefore, by estimating the amount of glucose using each light beam that passes through the finger web, the amount of glucose can be accurately estimated without being affected by whether the user is obese or not.

With reference to FIG. 9, the configuration of a blood measuring device 10 according to another embodiment will be described. FIG. 9 is a sectional view of a blood measuring device 10 according to another embodiment. Since the basic configuration of the blood measuring device 10 shown in this figure is the same as that shown in FIGS. 1 to 4, explanations of overlapping configurations and methods will be omitted, and the explanation will focus on the different parts.

The blood measuring device 10 has a main body 45, and each component constituting the blood measuring device 10 is built into the main body 45. Here, the light emitting section 11 and the light receiving section 19 built into the main body 45 are illustrated.

A waveguide 48 and a waveguide 49 protrude from the front end surface of the main body 45, a mirror 46 is built into the waveguide 48, and a mirror 47 is built into the waveguide 49. Further, a light receiving section 19 is arranged behind the waveguide 48, and a light emitting section 11 is arranged behind the waveguide 49. Further, an opening 50 is formed by opening the waveguide 48 below the mirror 46, and an opening 51 is formed by opening the waveguide 49 above the mirror 47. Further, mirror 46 and mirror 47 are arranged at the front ends of waveguide 48 and waveguide 49. Furthermore, a temperature measuring section 21 is arranged between the waveguide 48 and the waveguide 49.

An optical axis 22 is formed inside the main body 45, through which each light beam passes when measuring the amount of glucose. The optical axis 22 is defined to pass through the light emitting section 11 , the waveguide 49 , the mirror 47 , the aperture 51 , the aperture 50 , the mirror 46 , the waveguide 48 , and the light receiving section 19 .

When calculating the amount of glucose using the blood measuring device 10, first, a finger web is placed between the waveguide 48 and the waveguide 49. Thereby, the finger web is located between the openings 50 and 51. Furthermore, the temperature measuring section 21 measures the body temperature by contacting the finger web.

Next, the calculation control unit 17 irradiates each light beam from the light emitting unit 11 along the optical axis 22 . Each light beam emitted from the light emitting section 11 passes through the waveguide 49, is reflected by the mirror 47, passes through the aperture 51, passes through the finger web, passes through the aperture 50, is reflected by the mirror 46, and is reflected by the waveguide 47. 48 and reaches the light receiving point of the light receiving section 19. The arithmetic control unit 17 moves the light emitting unit 11 in the vertical direction to emit light from each light emitting point of the first light emitting unit 111 , the second light emitting unit 112 , and the third light emitting unit 113 along the optical axis 22 . It emits a light beam, a second light beam, and a third light beam. Here, the waveguide 48 and the waveguide 49 are spaced apart from each other to the extent that they do not press the finger web, or are in light contact with the finger web.

Next, the light receiving section 19 transmits an electric signal indicating the received light intensity of each light beam to the calculation control section 17. The arithmetic control unit 17 calculates the amount of glucose using the received light intensity of each light beam, the temperature of the finger web measured by the temperature measurement unit 21, etc. using a conversion formula such as a multiple regression formula.

In the blood measuring device 10 shown in FIG. 9, the waveguide 48 and the waveguide 49 do not press the finger web or a region in its vicinity. Therefore, the amount of glucose can be accurately calculated with good blood flow inside the finger web.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

For example, in the present embodiment described above, the amount of glucose was calculated using the first light beam, second light beam, and third light beam having different wavelengths, but two light beams (for example, the first light beam with a wavelength of 1310 nm, the The amount of glucose can also be calculated using the third light beam (1550 nm).

Moreover, the above-described blood measuring device 10 can also be used for purposes other than measuring the amount of glucose. For example, it may be possible to diagnose a disease such as cancer from the intensity of each light beam that passes through the human body and is received by the light receiving unit 19.

Furthermore, in the present embodiment described above, the finger formed between the thumb and index finger is used as the part to be measured, but a finger web formed between other fingers may also be used as the part to be measured. can.

10 Blood measuring device 11 Light emitting section 111 First light emitting section 112 Second light emitting section 113 Third light emitting section 12 Operation input section 13 Storage section 14 Lens 15 Display section 16 Actuator 17 Arithmetic control section 18 Part to be measured 19 Light receiving section 20 Upper plate Part 21 Temperature measurement part 22 Optical axis 231 Clamping part 232 Clamping part 24 Adductor pollicis muscle 25 First pressing part 26 Thenar ball 27 Second pressing part 28 Contact part 29 Contact part 30 Actuator storage part 31 Light emitting part storage part 32 Light-receiving unit housing 33 Inclined surface 34 Housing 35 Lid 36 Holder 37 Motor 38 Rotating shaft 39 Screwing part 40 Opening 41 Opening 42 Opening 43 Projection 44 Hole 45 Main body 46 Mirror 47 Mirror 48 Waveguide 49 Waveguide 50 Aperture 51 Aperture

Claims (3)

a light emitting unit including a first light emitting unit that emits a first light beam of a first wavelength; and a second light emitting unit that emits a second light beam of a second wavelength;
a light receiving unit that receives the first light beam and the second light beam that have passed through the measurement target area;
an arithmetic control unit that estimates the amount of components contained in blood based on the received light intensity of the first light beam and the second light beam;
a light emitting unit housing part in which the light emitting unit is stored;
a light-receiving unit housing part in which the light-receiving unit is stored;
an inclined surface formed in the vicinity of the light emitting unit housing and the light receiving unit housing;
a first contact portion forming one side surface;
a second contact portion forming the other side surface;
a pressing portion protruding outward from the inclined surface;
The first contact portion is a curved surface that is recessed inward so that a finger can easily fit therein ,
The second contact portion is a curved surface that is recessed inward so that a finger can easily fit therein ,
When measuring the amount of components contained in the blood at the measurement site,
The first contact portion contacts a user's finger,
the second contact portion contacts another finger of the user;
The pressing portion abuts on or near the ball of the user's foot,
the first contact portion contacts the thumb of the user;
The blood measuring device , wherein the second contact portion contacts the user's index finger . The first contact portion is a curved surface,
The blood measuring device according to claim 1, wherein the second contact portion is a curved surface. When the pressing part comes into contact with the ball of the user's foot or the vicinity thereof,
The blood measuring device according to claim 1, wherein the light emitting section, the light receiving section, and the region to be measured are arranged in a predetermined positional relationship.

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