Vital information measurement device, vital information measurement method, biological management system, and biological management method

Abstract

A vital information measurement method according to the present disclosure is for a vital information measurement device that is equipped with a first optical system having a wavelength region of 800-950 [nm] and a second optical system having a wavelength region including 1600 [nm]. The measurement method comprises: a first step for detecting, by the first optical system, an image that includes a blood vessel shape; a second step for aligning the image obtained by the first optical system with an image obtained by the second optical system; a third step for extracting a portion corresponding to the position of a blood vessel from the image obtained by the second optical system; and a fourth step for calculating HbA1c on the basis of image information extracted in the third step.

Description

Technical Field

[0001] The present disclosure technology relates to a vital information measurement device, a vital information measurement method, a biological management system, and a biological management method.

Background Art

[0002] In the course of a user's life, various information (hereinafter referred to as "vital information") that serves as an indicator of health status is collected by detecting biological substances contained in the user's body without the user's awareness, and the health status is unobtrusively fed back to the user in daily life. Technologies aiming at so-called routine medical check-ups are known.

[0003] For example, Patent Document 1 discloses a smart toilet system including a sensor chip for detecting biological substances as an example of a technology aiming at routine medical check-ups.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In a biological management system using a vital information measurement device such as the smart toilet system exemplified in Patent Document 1, the collected vital information can be used not only to be fed back to the user but also to be fed back to a medical institution. However, the business of feeding back a user's vital information to a medical institution using a biological management system has not actually spread. It is considered that the reason for this lack of spread is that the mechanism for preventing leakage of personal information regarding the user is not sufficient.

[0006] The present disclosure technology aims to provide a biometric management system and a biometric management method that are fundamentally robust against leakage of personal information.

Means for Solving the Problems

[0007] The vital information measurement method according to the present disclosure technology is a vital information measurement method of a vital information measurement device including a first optical system with a wavelength range from 800 [nm] to 950 [nm] and a second optical system including 1600 [nm] in the wavelength range, and includes: a first step of detecting an image including a blood vessel shape by the first optical system; a second step of aligning the image obtained by the first optical system and the image obtained by the second optical system; a third step of extracting a portion corresponding to the position of the blood vessel in the image obtained by the second optical system; and a fourth step of calculating HbA1c based on the image information extracted in the third step.

Effects of the Invention

[0008] Since the biometric management system according to the present disclosure technology includes the vital information measurement device having the above configuration, it is fundamentally robust against leakage of personal information.

Brief Description of the Drawings

[0009]

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[0010] Briefly speaking, the disclosed technology is a technology that studies human blood vessels, integrates high-precision personal authentication and healthcare, and contributes to preventive medicine.

[0011] Embodiment 1. FIG. 1 is an explanatory diagram showing the configuration of the biometric management system 1000 according to Embodiment 1. As shown in FIG. 1, the biometric management system 1000 according to Embodiment 1 is composed of a vital information measurement device 100 and a medical institution side data management device 200. Also, the vital information measurement device 100 and the medical institution side data management device 200 are connected via the Internet.

[0012] FIG. 2 is an explanatory diagram showing the configuration of the vital information measurement device 100 according to Embodiment 1. As shown in FIG. 2, the vital information measuring device 100 according to Embodiment 1 includes an inner holder 102, a finger detection unit 104 (104-1, 104-2), a first light source 110 (110-1, 110-2), a filter 112 for the first light source, a condenser lens 114 for the first light source, an area sensor 116 for the first light source, a second light source 120, a filter 122 for the second light source, a condenser lens 124 for the second light source, an area sensor 126 for the second light source, and a processing circuit 150. In the vital information measuring device 100, the first light source 110, the filter 112 for the first light source, the condenser lens 114 for the first light source, and the area sensor 116 for the first light source constitute a first optical system. Also, in the vital information measuring device 100, the second light source 120, the filter 122 for the second light source, the condenser lens 124 for the second light source, and the area sensor 126 for the second light source constitute a second optical system.

[0013] In FIG. 2, the figure marked "finger" represents the user's finger. Thus, the vital information measuring device 100 according to the disclosed technology is designed to be used with the user inserting a finger. The mode in which the user inserts a finger into the hole for use is the same as the usage of a "biometric key" that uses information on the shape pattern of blood vessels (hereinafter simply referred to as "blood vessel shape") as a key used at the entrance of a residential house. The vital information measuring device 100 according to the disclosed technology can continuously measure vital information without the user's awareness during the ordinary and natural operation of opening the key to the user's home entrance. Note that the mode in which the user inserts a finger into the hole for use is not limited to the biometric key used at the entrance of a residential house. The biometric key has a wide range of applicable uses, such as at the entrance of an apartment, at the entrance of an office at the workplace, in a passenger vehicle such as a car or a bus / taxi, and for the management of a bank account.

[0014] FIG. 3 is an explanatory diagram showing a modified example of the configuration of the vital information measuring device 100 according to Embodiment 1. As shown in FIG. 3, the vital sign measuring device 100 includes a beam splitter 130 in addition to the components shown in FIG. 2. As shown in FIG. 3, for the vital sign measuring device 100 according to the disclosed technology, a beam splitter 130 that branches the optical path of light may be used for the first optical system and the second optical system. In addition, the vital sign measuring device 100 may be provided with a coating that realizes the function of a wavelength selection filter on the reflection surface and the transmission surface of the beam splitter 130. By applying the coating, the first light source filter 112 and the second light source filter 122 can be omitted. Furthermore, a movable mirror may be used instead of the beam splitter 130 in the vital sign measuring device 100. For example, the vital sign measuring device 100 alternately lights the first light source 110 and the second light source 120, and selectively switches the optical path to the one corresponding to the light source by the movable mirror, and measures the image of the first optical system and the image of the second optical system not simultaneously but in time series. One of the effects of using the movable mirror is to eliminate the light attenuation that occurs in the beam splitter 130.

[0015] 《Vital Sign Measuring Device 100》 The vital sign measuring device 100 according to Embodiment 1 has at least the following two functions. The first function is to measure the shape of the blood vessels stretched around the inserted finger of the user. The second function is to measure vital signs, for example, HbA1c (hemoglobin A1c) in the blood, for the inserted finger of the user. The first function is mainly realized by the first optical system in the vital sign measuring device 100. This first function mainly realized by the first optical system realizes a function as a biometric key called blood flow authentication, vein authentication, etc. The second function is mainly realized by the second optical system in the vital sign measuring device 100. This second function mainly realized by the second optical system realizes a function as a non-invasive vital sign measuring instrument.

[0016] 《Inner Holder 102》 The inner holder 102 is a part inside the housing of the vital information measuring device 100 and is a component for keeping the user's finger in the same position and posture during use. The part described as "gap" in FIGS. 2 and 3 represents a feature of the shape of the inner holder 102, where a gap is provided between the inner holder 102 and the finger. With the device of providing a gap between the inner holder 102 and the finger, it becomes possible to capture a clearer image of the shape of the blood vessels stretched around the finger without compressing the blood vessels of the finger. The device of providing a gap between the inner holder 102 and the finger is particularly effective for users with thin blood vessels (such as women and children). The part described as "space" in FIGS. 2 and 3 represents a feature of the shape of the inner holder 102, where a space is provided at that part of the inner holder 102. With this device, even when the fingernail is long or when wearing false nails, the finger can be kept in the same position and posture without the nails hitting the inner holder 102.

[0017] The inner holder 102 also has the function of blocking unnecessary light from the outside. When unnecessary light enters from the outside, it becomes difficult to obtain an image for achieving the purpose of the present disclosure technology in the first light source area sensor 116 and the second light source area sensor 126 described later. If it is not sufficiently shielded from light, it becomes particularly difficult to extract the contour of the finger in the first light source area sensor 116 and the second light source area sensor 126 described later, and an image with the desired contrast cannot be obtained. Therefore, the inner holder 102 may be configured to include a light-shielding sheet on the fingernail part. The light-shielding sheet to be adopted may be selected by determining its performance such as absorbance from the viewpoints of the degree of extraction of the finger contour and whether it is the desired contrast.

[0018] 《Finger Detection Unit 104 (104-1, 104-2)》 The finger detection unit 104 (104-1, 104-2) is a component that detects the user's finger inserted into the inner holder 102. As shown in FIGS. 2 and 3, the finger detection unit 104 may be composed of at least two elements: a part corresponding to the so-called nail of the finger (finger detection unit 104-1) and a part corresponding to the tip of the finger (finger detection unit 104-2). The finger detection unit 104 may be configured to measure the capacitance by allowing a weak current to flow between, for example, the finger detection unit 104-1 and the finger detection unit 104-2. By measuring the capacitance, the finger detection unit 104 can distinguish and detect between the case where an inorganic object such as a ballpoint pen is inserted into the inner holder 102 and the case where a human finger is inserted.

[0019] 《The First Light Source 110 Constituting the First Optical System》 The first light source 110 constituting the first optical system is a light source for measuring the shape of blood vessels stretched around the finger. Specifically, the first light source 110 constituting the first optical system preferably emits near-infrared light (NIR) with a wavelength range from 800 [nm] to 950 [nm]. More preferably, the first light source 110 emits near-infrared light (NIR) with a wavelength range from 840 [nm] to 950 [nm]. The first light source 110 in the first optical system may be realized by, for example, an LED (Light Emitting Diode). As shown in FIGS. 2 and 3, the first light source 110 (110-1, 110-2) may be composed of a plurality of elements so as to irradiate the entire finger with light. In FIGS. 2 and 3, two first light sources 110 (110-1, 110-2) are shown, but the disclosed technology is not limited thereto. The first light source 110 (110-1, 110-2, …) according to Embodiment 1 may be two or more. As shown in FIGS. 2 and 3, the first light source 110 (110-1, 110-2) may be arranged in the inner holder 102 so as to contact the so-called nail side (outer side) of the finger to be measured. In this way, bringing the light source into contact with the finger contributes to obtaining a clear image in the first light source area sensor 116 described later. In FIGS. 2 and 3, the figure described as "circuit board" represents a substrate such as a PCB (Printed Circuit Board). The first light source 110 (110-1, 110-2, …) is mounted on a substrate such as a PCB.

[0020] 《Filter 112 for the First Light Source Constituting the First Optical System》 The filter 112 for the first light source constituting the first optical system is an optical filter that selectively passes only the infrared rays (IR) emitted from the first light source 110 and passing through the finger to be measured. In other words, the filter 112 for the first light source constituting the first optical system may be a filter having the characteristic of passing light in the wavelength range from 800 [nm] to 950 [nm] and blocking light in the wavelength range from 1500 [nm] to 1700 [nm], which is the wavelength range of the second light source 120 described later.

[0021] 《Condensing Lens 114 for the First Light Source Constituting the First Optical System》 The condensing lens 114 for the first light source constituting the first optical system is an optical lens that condenses the near-infrared rays (NIR) that have passed through the filter 112 for the first light source. The focal point of the condensing lens 114 for the first light source is arranged so as to coincide with the light-receiving portion of the area sensor 116 for the first light source described later. By arranging in this way, the area sensor 116 for the first light source can detect an image of blood vessels stretched around the finger.

[0022] 《Area Sensor 116 for the First Light Source Constituting the First Optical System》 The area sensor 116 for the first light source that constitutes the first optical system is a component that detects an image of blood vessels stretched around a finger. Specifically, the area sensor 116 for the first light source that constitutes the first optical system is an area sensor such as a CMOS image sensor (Complementary Metal Oxide Semiconductor) with high sensitivity to near-infrared light. More preferably, the area sensor 116 for the first light source is a CMOS image sensor having a peak in the spectral sensitivity characteristic near 850 [nm]. Note that a CMOS image sensor may also be referred to as a CMOS camera.

[0023] 《The Second Light Source 120 that Constitutes the Second Optical System》 The second light source 120 that constitutes the second optical system is a light source for measuring HbA1c in blood with respect to the inserted finger of the user. As the second light source 120 that constitutes the second optical system, one that emits infrared light with a longer wavelength than the first light source 110, specifically, in the wavelength range from 1500 [nm] to 1700 [nm], is selected. The reason why the wavelength range of the second light source 120 is selected to be from 1500 [nm] to 1700 [nm] is that glucose has the property of absorbing light near 1600 [nm]. Therefore, the second light source 120 is preferably selected so that 1600 [nm] is included in its wavelength range. Similar to the first light source 110, the second light source 120 that constitutes the second optical system may be realized by, for example, an LED. In FIGS. 2 and 3, the number of the second light sources 120 is one, but the present disclosed technology is not limited to this. The second light source 120 may be configured with a plurality of elements so as to irradiate the entire finger with light. As shown in FIGS. 2 and 3, the second light source 120 may be arranged in the inner holder 102 so as to contact the so-called nail side (outer side) of the finger to be measured. In this way, bringing the light source into contact with the finger contributes to obtaining a clear image in the area sensor 126 for the second light source described later. Similar to the first light source 110, the second light source 120 is mounted on a substrate such as a PCB.

[0024] 《The Filter 122 for the Second Light Source that Constitutes the Second Optical System》 The filter 122 for the second light source that constitutes the second optical system is an optical filter that selectively passes only the infrared rays (IR) emitted from the second light source 120 and passing through the finger to be measured. In other words, the filter 122 for the second light source that constitutes the second optical system may be a filter having the characteristic of passing light in the wavelength range from 1500 [nm] to 1700 [nm] and blocking light in the wavelength range from 800 [nm] to 950 [nm] which is the wavelength range of the first light source 110.

[0025] 《The condenser lens 124 for the second light source that constitutes the second optical system》 The condenser lens 124 for the second light source that constitutes the second optical system is an optical lens that condenses the infrared rays (IR) that have passed through the filter 122 for the second light source. The focal point of the condenser lens 124 for the second light source is arranged so as to coincide with the light receiving portion of the area sensor 126 for the second light source described later. By arranging in this way, the area sensor 126 for the second light source can detect an image for measuring HbA1c in blood.

[0026] 《The area sensor 126 for the second light source that constitutes the second optical system》 The area sensor 126 for the second light source that constitutes the second optical system is a component that detects an image for measuring HbA1c in blood. Specifically, the area sensor 126 for the second light source that constitutes the second optical system is preferably an area sensor equipped with an InGaAs sensor. InGaAs means indium gallium arsenide. The InGaAs sensor is a sensor having high sensitivity in the near-infrared wavelength range from 950 [nm] to 1700 [nm]. Note that the InGaAs sensor may also be referred to as an InGaAs camera.

[0027] 《The beam splitter 130》 The beam splitter 130 is a component that branches the optical path into a first optical system and a second optical system. As a device for making the vital information measuring device 100 according to the disclosed technology compact, optical elements such as the beam splitter 130 may be appropriately used. The beam splitter 130 can be considered in various forms, such as a polarization beam splitter, a half mirror, a prism type, a planar type, or a wedge substrate type. However, the specific form may be appropriately determined according to design specifications and the like.

[0028] 《Processing Circuit 150》 The processing circuit 150 is a component for controlling the vital information measuring device 100. The processing circuit 150 may be dedicated hardware or a CPU (Central Processing Unit) that executes a program stored in a memory.

[0029] When the processing circuit 150 is dedicated hardware, the processing circuit 150 may be an ASIC, an FPGA, or the like. In this case, each function of the vital information measuring device 100 is realized by the ASIC or FPGA or the like that is the processing circuit 150. When the processing circuit 150 is a CPU, each function of the vital information measuring device 100 is realized by software. The software is described as a program and stored in a memory. The processing circuit 150 realizes each function of the vital information measuring device 100 by reading and executing the program stored in the memory. The processing circuit 150 includes a storage device such as a memory, whether it is dedicated hardware or a CPU that executes a program stored in a memory.

[0030] 《Regarding the Processing Steps of the Vital Information Measuring Device 100》 FIG. 4 is a flowchart showing the processing steps of the vital information measuring method according to Embodiment 1. In other words, FIG. 4 is a flowchart showing the processing steps of the vital information measuring device 100 realized by the processing circuit 150.

[0031] The block described as "ST1" shown in FIG. 4 represents the first step of the vital information measurement method according to Embodiment 1, and specifically represents the step of detecting the blood vessel shape. The step of detecting the blood vessel shape is mainly realized by the first optical system and the processing circuit 150 of the vital information measurement device 100. In the step of detecting the blood vessel shape, the processing circuit 150 performs image processing such as binarization on the detection result of the first light source area sensor 116 to detect the blood vessel shape.

[0032] The processing circuit 150 can compare the blood vessel shape detected in the first step with the data of the pre-registered user's blood vessel shape to identify the user. This processing step is the processing step related to the first action described above, and is a processing step that realizes the function as a biometric key called blood flow authentication, vein authentication, etc. Note that biometric authentication is a technology that utilizes the characteristic that physical characteristics vary from person to person, and identifies whether a person is the same by collating the pre-registered biometric information data at the time of authentication.

[0033] As described above, since the blood vessel shape of a human is an internal physical characteristic, it is more stable compared to fingerprints, which are external physical characteristics. However, in the case of children in the growth period, etc., the blood vessel shape may change gradually with growth. Therefore, in the first step of detecting the blood vessel shape, the processing circuit 150 may appropriately update the data of the pre-registered user's blood vessel shape as necessary.

[0034] The block labeled "ST2" shown in FIG. 4 represents the second step of the vital information measurement method according to Embodiment 1. Specifically, it represents the step of aligning the image obtained by the first light source area sensor 116 and the image obtained by the second light source area sensor 126. The step of performing the alignment is mainly realized by the processing circuit 150. In the step of performing the alignment, the processing circuit 150 may use, for example, information obtained by a calibration operation performed in advance. Also, in the step of performing the alignment, the processing circuit 150 may use, for example, characteristic information that commonly exists in both images, such as the contour of a finger, in each of the image obtained by the first light source area sensor 116 and the image obtained by the second light source area sensor 126.

[0035] As shown in FIG. 3, by using the beam splitter 130, it is virtually possible to arrange the first light source area sensor 116 and the second light source area sensor 126 at the same position with respect to the position of the finger. Therefore, considering this second step, it can also be said that it is preferable to use the beam splitter 130. Note that even if the beam splitter 130 is not used, the processing circuit 150 can realize the alignment by performing image processing to process one of the images based on the other image.

[0036] In the block labeled "ST2" shown in FIG. 4, the black circular figure represents glucose. Glucose is a simple sugar with the molecular formula C6H 12 O6 and is also called grape sugar. As described above, glucose has the property of absorbing light near 1600 [nm]. Therefore, in the image obtained by the second light source area sensor 126, the glycated substance appears black. The present disclosed technology calculates the amount of glycated hemoglobin necessary for calculating HbA1c by utilizing this property.

[0037] The block described as "ST3" shown in FIG. 4 represents the third step of the vital information measurement method according to Embodiment 1. Specifically, in the image obtained by the second light source area sensor 126, it represents the step of extracting the portion corresponding to the position of the blood vessel. The step of extracting the portion corresponding to the position of the blood vessel is mainly realized by the processing circuit 150. In the step of extracting the portion corresponding to the position of the blood vessel, the processing circuit 150 utilizes the alignment information implemented in the second step.

[0038] The idea of realizing an optical blood glucose measuring device by focusing on the property that glucose absorbs light near 1600 [nm] may not be new. However, as far as the inventor knows, there is no optical blood glucose measuring device approved as a medical device in Japan. In order for an optical blood glucose measuring device to be approved as a medical device in Japan, the measurement accuracy must be high to a reliable extent. Conventional devices do not have the above-mentioned third step according to the disclosed technology, so the value measured by the sensor is affected by biological tissues other than blood vessels. More specifically, in the case of conventional devices, even when the user's finger is irradiated with light near 1600 [nm] and imaged, the light passing through biological tissues other than blood vessels is also included, resulting in the problem that the desired contrast image cannot be obtained. It is considered that being affected by such biological tissues other than blood vessels is the cause of the inability to improve the measurement accuracy. The vital information measuring device 100 according to the disclosed technology can improve the measurement accuracy because the processing circuit 150 implements the above-mentioned third step, that is, the step of extracting the portion corresponding to the position of the blood vessel.

[0039] The block described as "ST4" shown in FIG. 4 represents the fourth step of the vital information measurement method according to Embodiment 1. Specifically, it represents the step of calculating HbA1c. As shown in FIG. 4, HbA1c is given by the following formula. TIFF0007703112000001.tif12160 As shown in formula (1), HbA1c represents the proportion of glycated hemoglobin in total hemoglobin. Generally, percentage [%] is often used to represent HbA1c.

[0040] The step of calculating HbA1c is mainly realized by the processing circuit 150. In the step of calculating HbA1c, the processing circuit 150 uses the image information obtained by extracting the part corresponding to the position of the blood vessel from the image obtained by the second light source area sensor 126, which was obtained in the third step. Specifically, the processing circuit 150 estimates the ratio of the amount of glycated hemoglobin to the amount of total hemoglobin shown on the right side of formula (1) based on the image information obtained by extracting the part corresponding to the position of the blood vessel, and calculates HbA1c.

[0041] The processing circuit 150 may adopt a configuration equipped with a learned artificial intelligence in order to estimate the amount of total hemoglobin and the amount of glycated hemoglobin from the image information. The artificial intelligence included in the processing circuit 150 may be realized by an artificial neural network such as a CNN (Convolution Neural Network), for example. Also, the artificial intelligence is not limited to an artificial neural network and may be realized by a mathematical model (hereinafter referred to as a "learning model") based on learning. The learning of the artificial intelligence included in the processing circuit 150 may be in a mode where the HbA1c obtained by actually collecting blood and performing a blood test is used as the correct label, the correct label is attached to the image information obtained by extracting the part corresponding to the position of the blood vessel from the image obtained by the second light source area sensor 126 to obtain teacher data, and supervised learning is performed.

[0042] The block described as "ST5" shown in FIG. 4 represents the fifth step of the vital information measurement method according to Embodiment 1, and specifically represents the step of calculating a blood glucose level. The step of calculating the blood glucose level is mainly realized by the processing circuit 150. In the step of calculating the blood glucose level, the processing circuit 150 uses the image information obtained by extracting the portion corresponding to the position of the blood vessel from the image obtained by the second light source area sensor 126, which was obtained in the third step.

[0043] The blood glucose level is the concentration of glucose in the blood. The processing circuit 150 may calculate the blood glucose level by means of the aforementioned learned artificial intelligence. Similar to the case of calculating HbA1c, the learning of the artificial intelligence included in the processing circuit 150 may be in such a manner that the blood glucose level obtained by actually collecting blood and performing a blood test is used as the correct label, the correct label is attached to the image information obtained by extracting the portion corresponding to the position of the blood vessel from the image obtained by the second light source area sensor 126 to serve as teacher data, and supervised learning is performed.

[0044] Although not shown in the flowchart of FIG. 4, after the fifth step, the processing circuit 150 may perform a process of feeding back the vital information to the user. The process of feeding back the vital information to the user may specifically be to display the vital information on a display. Further, the processing circuit 150 may store in advance the normal values and abnormal values of the vital information, and when the measured vital information is an abnormal value, may display a message recommending a medical examination to the user.

[0045] FIG. 5 is an explanatory diagram showing the data structure of the data obtained by the disclosed technology. As shown in FIG. 5, the data obtained by the disclosed technology is characterized by having a data structure in which biometric information and vital information are integrated. Among the data of the data structure shown in FIG. 5, the biometric information is biometric information based on the blood vessel shape obtained in the first step of the vital information measurement method according to Embodiment 1. Among the data of the data structure shown in FIG. 5, the vital information is vital information including HbA1c obtained in the fourth step of the vital information measurement method according to Embodiment 1 and blood glucose level obtained in the fifth step.

[0046] The vital information measuring device 100 according to the disclosed technology may be provided with a structure for measuring blood oxygen saturation (SpO2), blood pressure, and pulse in addition to HbA1c and blood glucose level. For example, the vital information measuring device 100 according to the disclosed technology may be configured to also have a structure employed in a pulse oximeter for measuring blood oxygen saturation and pulse. Specifically, the vital information measuring device 100 according to the disclosed technology may be provided with a mechanism for sandwiching the fingertip using the principle of a lever (teko) at the portion where the tip of the finger to be measured hits, that is, the portion of the finger detection unit 104-2 in FIGS. 2 and 3, as a structure for measuring blood oxygen saturation and pulse.

[0047] In the biometric management system 1000 according to the disclosed technology, the vital information measuring device 100 transmits the data of the data structure shown in FIG. 5 to the medical institution side data management device 200 via the Internet or the like. As described above, since the data structure adopted by the disclosed technology is a data structure in which biometric information and vital information are integrated, there is no mistake in taking the vital information as that of another user. In other words, the biometric management system 1000 according to the disclosed technology can suppress the risk of being mistaken for that of another user in principle and feedback the vital information of the user to the medical institution.

[0048] To prevent information leakage, that is, to prevent vital information from being stolen by a third party, it is conceivable to encrypt the data handled by the present disclosure technology shown in FIG. 5. The biological management system 1000 according to the present disclosure technology focuses on the data structure of the data handled by the present disclosure technology shown in FIG. 5 and can also use two encryption keys (also referred to as "encryption keys"). That is, the biological management system 1000 according to the present disclosure technology can use one common encryption key for encrypting biometric authentication information and an individual encryption key assigned to each user. The individual encryption key assigned to each user is used to encrypt vital information among the data. These two types of encryption keys are shared between the vital information measuring device 100 and the medical institution side data management device 200. The vital information measuring device 100, which is the transmission side of the biological management system 1000, encrypts the biometric authentication information among the data of one user with the common encryption key and encrypts the vital information with the individual encryption key. The encrypted data is sent to the medical institution side data management device 200 via the Internet. The medical institution side data management device 200, which is the receiving side of the biological management system 1000, decrypts the biometric authentication information among the data using the common encryption key for the sent data. The medical institution side data management device 200 compares the decrypted biometric authentication information, that is, the image data of the blood vessel shape, with the pre-registered blood vessel shape data of the user to identify which user the data belongs to. Next, the medical institution side data management device 200 decrypts the vital information among the data using the individual encryption key assigned to each user. In this way, the method of the present disclosure technology using two types of encryption keys, namely the common encryption key and the individual encryption key, shall be referred to as the "two-stage encryption method" in this specification.

[0049] An excellent effect of the vital information measuring device 100 according to the present disclosure technology is that since the vital information measuring device 100 has a biometric authentication function, it can easily associate vital information with the true user (the true owner of the vital information) without misidentification. In addition, as a biometric function, it is also conceivable to use fingerprints, which can also identify an individual with information related to the fingers. Certainly, fingerprints are excellent as a means of identifying an individual in the context of criminal investigations. However, since fingerprints are on the outside of the body, they are easily damaged. For example, if alcohol disinfection is frequently repeated, the grooves of fingerprints become shallower, and in the case of optical detection, they are inferior in terms of stability compared to the blood vessel shape, which is information inside the body.

[0050] Another excellent effect of the vital information measurement device 100 according to the disclosed technology is that while it is a non-invasive and user-friendly optical measurement method, since it is possible to extract the portion corresponding to the position of the blood vessels from the image obtained by the area sensor 126 for the second light source, the influence of living tissues other than blood vessels is eliminated, and the measurement accuracy is high.

[0051] Another excellent effect of the vital information measurement device 100 according to the disclosed technology is that it is possible to continuously measure vital information without the user being aware during an ordinary and unobtrusive operation of opening the key to the front door of the house.

[0052] An excellent effect of the living body management system 1000 according to the disclosed technology is that since a two-stage encryption method can be adopted for data having a data structure in which biometric authentication information and vital information are integrated, it is fundamentally robust against leakage of personal information.

[0053] Embodiment 2. The vital information measurement device, vital information measurement method, living body management system, and living body management method according to Embodiment 2 are modified examples of the vital information measurement device, vital information measurement method, living body management system, and living body management method according to the disclosed technology. In Embodiment 2, the same reference numerals as those used in Embodiment 1 are used unless otherwise specified. Also, in Embodiment 2, descriptions overlapping with Embodiment 1 are omitted as appropriate.

[0054] FIG. 6 is a diagram for explaining the processing performed by the processing circuit 150 on the images (Images 1-3) handled by the vital information measurement device 100 according to the disclosed technology. As described above, the step of detecting the blood vessel shape is mainly realized by the first optical system and the processing circuit 150 of the vital information measurement device 100. In the step of detecting the blood vessel shape, the processing circuit 150 performs image processing such as binarization on the detection result of the first light source area sensor 116 to detect the blood vessel shape. Images 1, 2, and 3 in FIG. 6 are the blood vessel shapes of a certain subject before image processing such as binarization, obtained by the first optical system under different conditions respectively. As shown in FIG. 6, the processing circuit 150 performs image processing to delete background information (the black solidly painted portions in Images 1-3) and perform "cropping processing" on the finger images.

[0055] The finger image cut out from Image 1 is overall bright, and is an example where the blood flow concentration has a small density difference compared to the surrounding area when extracting the boundary between blood vessels and others. The finger image cut out from Image 2 is an example where the blood flow concentration has a density difference at a reference level compared to the surrounding area when extracting the boundary between blood vessels and others. The finger image cut out from Image 3 is overall dark, and is an example where the blood flow concentration has a large density difference compared to the surrounding area when extracting the boundary between blood vessels and others.

[0056] FIG. 7 is a graph (showing the average value of luminance) representing the luminance values of pixels as a histogram after the cropping process of the finger images for Images 1-3 in FIG. 6. The left graph in FIG. 7 is the luminance value histogram for the finger image cut out from Image 1. The middle graph in FIG. 7 is the luminance value histogram for the finger image cut out from Image 2. Also, the right graph in FIG. 7 is the luminance value histogram for the finger image cut out from Image 3. In each graph of FIG. 7, “X” on the horizontal axis represents the class (luminance value) in the histogram, and “Y” on the vertical axis represents the frequency (number of pixels) in the histogram, respectively. As shown in FIG. 7, by referring to the average value of the luminance for each pixel of the finger image, it is also possible to use it as an index for determining the light and shade of the blood flow concentration. In the technical field of image processing, the luminance value histogram is sometimes referred to as the pixel value histogram.

[0057] FIG. 8 is a graph (showing the maximum peak of luminance) representing the luminance values of pixels as a histogram after the cut-out process of the finger image for images 1-3 in FIG. 6. The left graph in FIG. 8 is the luminance value histogram for the finger image cut out from image 1. The central graph in FIG. 8 is the luminance value histogram for the finger image cut out from image 2. The right graph in FIG. 8 is the luminance value histogram for the finger image cut out from image 3. Similar to FIG. 7, in each graph of FIG. 8, “X” on the horizontal axis represents the class (luminance value) in the histogram, and “Y” on the vertical axis represents the frequency (number of pixels) in the histogram, respectively. As shown in FIG. 8, by referring to the frequency of the maximum peak of luminance in the finger image, it is also possible to use it as an index for determining the light and shade of the blood flow concentration.

[0058] As described above, glucose has the property of absorbing light near 1600 [nm]. In the luminance histograms shown in FIGS. 7 and 8, the phenomenon that the maximum peak occurs on the lower luminance side is due to the fact that the blood flow part in the image appears black due to the above property.

[0059] FIG. 9 is an explanatory diagram showing the configuration of the vital information measuring device 100 according to Embodiment 2. As can be seen by comparing FIG. 2 according to Embodiment 1 and FIG. 9 according to Embodiment 2, the vital information measuring device 100 according to Embodiment 2 includes a second light source photodiode 126B instead of the second light source area sensor 126. As described above, the vital information measuring device 100 according to the disclosed technology may be configured to include the second light source photodiode 126B instead of the second light source area sensor 126.

[0060] As described above, since the conventional optical blood glucose measuring device does not have the third step shown in the first embodiment, the value measured by the sensor is affected by biological tissues other than blood vessels. More specifically, in the conventional device, even when the finger of the user is irradiated with light near 1600 [nm] and imaged, the light passing through biological tissues other than blood vessels is also included, resulting in the problem that the image of the contrast that is originally desired cannot be obtained. Being affected by such biological tissues other than blood vessels was the cause of the inability to improve the measurement accuracy. In the vital information measuring device 100 according to the second embodiment, the data obtained in the second step does not include the PD output information, that is, the position information of the blood vessels, and the process of extracting the portion corresponding to the position of the blood vessels is not performed in the processing circuit 150. However, the vital information measuring device 100 according to the second embodiment improves the accuracy of blood glucose value calculation by referring not only to the PD data obtained from the long-wavelength IR but also to the luminance information (also referred to as "shading information") of the blood flow image from the near-infrared IR for personal authentication. In the first embodiment, ST3 represents the step of extracting the portion corresponding to the position of the blood vessels in the image obtained by the second light source area sensor 126. On the other hand, in the second embodiment, it can be said that ST3 is replaced with the step of referring to the shading information of the blood flow obtained by the second light source photodiode 126B and reflecting it in the blood glucose value calculation.

[0061] FIG. 10 is a diagram illustrating the luminance histogram of an image. In the graph shown in FIG. 10, "X" on the horizontal axis represents the class (luminance value) in the histogram, and "Y" on the vertical axis represents the frequency (number of pixels) in the histogram. In the graph shown in FIG. 10, the numbers from 0 to 255 are assigned to "X" representing the class, indicating that each pixel of the image takes a value of 8 bits (256 gradations). The maximum peak shown in FIG. 8 can be extracted as satisfying the following conditions when X takes an integer from 0 to 255. TIFF0007703112000002.tif43166 Here, Y that appears in Equation (2) Peak represents a set of maximum peaks. In addition, when the luminance (X) that empirically takes the maximum peak is known, without using the conditional expression of Equation (2), the frequency (number of pixels) at the luminance (X) that empirically takes the maximum peak (described as "predetermined luminance" in FIG. 8) may be referred to as an index for determining whether the amount of light is appropriate.

[0062] When conditions such as the amount of light are different in this way, the image obtained by the first optical system changes in the luminance of its pixels. On the other hand, as described above, since glucose has the property of absorbing light near 1600 [nm], the luminance also changes depending on the blood glucose level of the subject. In response to this problem, the vital information measuring device according to the present disclosure technology includes a first optical system specialized for measuring the shape of the blood vessels stretched around the inserted finger of the user, and a second optical system specialized for measuring vital information, such as HbA1c (hemoglobin A1c) in the blood, for the inserted finger of the user. These are provided independently and function in cooperation. Therefore, the vital information measuring device according to the present disclosure technology can distinguish between factors based on conditions such as the amount of light and factors based on the amount of blood glucose, and can be put into actual use after performing appropriate calibration. In the vital information measuring device according to the present disclosure technology, for calibration, a simulated finger (finger model) designed for calibration may be used without using the finger of an actual subject.

[0063] The technical feature of the vital information measuring device according to Embodiment 2 is that in the processing circuit 150, factors based on conditions such as the amount of light and factors based on the amount of blood glucose are distinguished, and appropriate calibration is performed. The vital information measurement device according to Embodiment 2 also exhibits the excellent effects described in Embodiment 1.

[0064] Embodiment 3. The vital information measurement device, vital information measurement method, biological management system, and biological management method according to Embodiment 3 are modified examples of the vital information measurement device, vital information measurement method, biological management system, and biological management method according to the present disclosed technology. In Embodiment 3, unless otherwise specified, the same reference numerals as those used in the previous embodiments are used. Also, in Embodiment 3, descriptions overlapping with the previous embodiments are omitted as appropriate.

[0065] Now, the vital information measurement device according to the present disclosed technology may have a display screen such as a display on the device itself, or may be able to transmit display information to external devices such as a personal computer or a mobile terminal by wire or wirelessly.

[0066] FIG. 11 is an image diagram showing the display content of the vital information measurement device according to Embodiment 3. The vital information measurement device according to the present disclosed technology continuously measures vital information without the user's awareness during an ordinary and unobtrusive operation such as opening the key to the front door of the house. Therefore, the user measures with the vital information measurement device according to the present disclosed technology at most about 2 to 10 times a day, and it is not assumed that a continuous time graph of blood glucose levels as shown in FIG. 11 can be obtained (FIG. 11 is merely an image diagram).

[0067] FIG. 11 suggests that based on the user's average blood glucose level, the blood glucose level can be divided into five regions, and information such as normal range, borderline hyperglycemia, hyperglycemia, borderline hypoglycemia, and hypoglycemia can be displayed to the user or medical staff according to the measured blood glucose level. Regarding how to classify the blood glucose level, those announced by academic societies, those based on international standards, etc. may be referred to.

[0068] The technical features of the vital information measuring device according to Embodiment 3 are that the device itself has a display screen such as a display, or can transmit display information to external devices such as a personal computer or a mobile terminal by wire or wirelessly. The vital information measuring device according to Embodiment 3 also exhibits the excellent effects described in Embodiment 1.

Industrial Applicability

[0069] The disclosed technology can be applied to a living body management system and a living body management method that realize a so-called routine medical examination that unobtrusively feedbacks the health status to users and medical institutions in daily life, and has industrial applicability. Furthermore, with the spread of Web3.0, which can be realized by blockchain technology, that is, the next-generation decentralized Internet, the disclosed technology can become a standard technology and has high industrial applicability.

Explanation of Signs

[0070] 100 Vital information measuring device, 102 Inner holder, 104 Finger detection unit, 110 First light source, 112 Filter for the first light source, 114 Condensing lens for the first light source, 116 Area sensor for the first light source, 120 Second light source, 122 Filter for the second light source, 124 Collecting lens for the second light source, 126 Area sensor for the second light source, 130 Beam splitter, 150 Processing circuit, 200 Medical institution side data management device, 1000 Living body management system.

Claims

1. A method for measuring vital information of a vital information measuring device, comprising: a first optical system having a wavelength range from 800 [nm] to 950 [nm]; and a second optical system having a wavelength range including 1600 [nm], the method comprising: a first step of detecting an image including a blood vessel shape by the first optical system; a second step of aligning the image obtained by the first optical system with the image obtained by the second optical system; a third step of extracting a portion corresponding to the position of the blood vessel in the image obtained by the second optical system; a fourth step of calculating HbA1c based on the image information extracted in the third step, the method for measuring vital information.

2. The image obtained by the second optical system is an image that does not include the position information of the blood vessel. Instead of the alignment in the second step and the third step, after the first step and before the fourth step, a processing step of calibrating the luminance value of the image obtained by the second optical system based on the luminance histogram of the image obtained by the first optical system is performed. In the fourth step, HbA1c is calculated based on the calibrated luminance value instead of based on the image information extracted in the third step. The method for measuring vital information according to Claim 1.

3. An inner holder that is a part inside the housing and keeps the user's finger in the same position and posture during use, a finger detection unit that detects the user's finger inserted into the inner holder, a first light source that emits infrared rays having a wavelength range from 800 [nm] to 950 [nm], a first light source filter that selectively passes only the infrared rays emitted from the first light source and passing through the finger to be measured, a first light source condenser lens that condenses the infrared rays passing through the first light source filter, a first light source area sensor that detects an image of blood vessels stretched around the finger, a second light source that emits infrared rays having a wavelength range from 1500 [nm] to 1700 [nm], a second light source filter that selectively passes only the infrared rays emitted from the second light source and passing through the finger to be measured, a second light source condenser lens that condenses the infrared rays passing through the second light source filter, a second light source area sensor that detects an image for measuring HbA1c in blood, a processing circuit that performs control, and the device is provided with these components. The first light source, the filter for the first light source, the condenser lens for the first light source, and the area sensor for the first light source form a first optical system. The second light source, the filter for the second light source, the condenser lens for the second light source, and the area sensor for the second light source form a second optical system. The processing circuit performs a first step of detecting an image including a blood vessel shape by the first optical system, a second step of aligning the image obtained by the first optical system and the image obtained by the second optical system, a third step of extracting a portion corresponding to the position of the blood vessel in the image obtained by the second optical system, and a fourth step of calculating HbA1c based on the image information extracted in the third step. Vital information measuring device.

4. A biological management system comprising the vital information measuring device according to claim 3 and a medical institution side data management device installed in a medical institution, wherein the data transmitted from the vital information measuring device and received by the medical institution side data management device has a data structure in which biometric authentication information and vital information are integrated. Biological management system.

5. A biological management method for a biological management system comprising the vital information measuring device according to claim 3 and a medical institution side data management device installed in a medical institution, wherein the vital information measuring device encrypts biometric authentication information among the data of one person with a common encryption key and encrypts vital information with an individual encryption key assigned to each user, and the medical institution side data management device decrypts the biometric authentication information using the common encryption key for the transmitted data, compares it with the pre-registered blood vessel shape data to identify whose information it is, and decrypts the vital information using the individual encryption key. Biological management method.

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