Measurement apparatus, measurement system, and measurement method

Abstract

To provide a measurement apparatus capable of easily detecting variation in the state of a skin surface.SOLUTION: A measurement apparatus comprises: a signal acquisition unit which acquires a signal value showing the intensity of light having passed through a living body or reflected by the living body; a color information acquisition unit which converts the signal value to color information; a color information determination unit which determines whether the color information meets a determination condition; and a signal correction unit which adopts a signal value convertible to color information meeting the determination condition.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a measurement device, a measurement system, and a measurement method. [Background technology]

[0002] Patent document 1 discloses a technology in which an image of the skin is captured while removing gloss by incorporating a polarized lens into the input optical system, the captured still image is binarized, the proportion of the area of ​​the area where dry desquamation occurs to the total area is quantified as the roughness rate, and the quantification result of the roughness is output. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 63-161935 Summary of the Invention [Problem to be solved by the invention]

[0004] By irradiating a living body with light and measuring the transmitted or reflected light, it is possible to measure the state of the inside of the skin, for example, biological information such as blood pressure, heart rate, and blood oxygen saturation. However, when the skin surface is rough, the diffuse reflected light and regular reflected light from the skin surface are stronger than when the skin surface is not rough, and the measurement accuracy may decrease. In the technology disclosed in Patent Document 1, a polarized lens is used to remove gloss in order to suppress the diffuse reflected light and regular reflected light. However, in the technology disclosed in Patent Document 1, the design of the optical system that matches the focus and polarization direction of the polarized lens becomes complicated. Therefore, one aspect of the present disclosure aims to provide a measuring device, a measuring system, and a measuring method that can easily detect changes in the state of the skin surface. [Means for solving the problem]

[0005] A measurement device according to one embodiment of the present disclosure includes a signal acquisition unit that acquires a signal value indicating the intensity of light transmitted through or reflected by a living body, a color information acquisition unit that converts the signal value into color information, a color information determination unit that determines whether the color information satisfies a determination condition, and a signal correction unit that adopts a signal value that can be converted into color information that satisfies the determination condition.

[0006] A measurement system according to an embodiment of the present disclosure includes the measurement device and an information processing device that calculates biological information from a time change in a signal value adopted by the signal correction unit.

[0007] A measurement method according to one embodiment of the present disclosure includes a step of acquiring a signal value indicating the intensity of light transmitted through or reflected by a living body, a step of converting the signal value into color information, a step of determining whether the color information satisfies a judgment condition, and a step of adopting a signal value that can be converted into color information that satisfies the judgment condition. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a block diagram showing an example of a configuration of a measurement system. [Diagram 2] 4 is a flowchart showing an example of the operation of the measurement device according to the first embodiment. [Diagram 3] 11 is a diagram illustrating a color gamut threshold and a graph showing an example of a change in a determination index over time. [Figure 4] 10 is a flowchart showing an example of the operation of a measurement device according to a modified example of the first embodiment. [Diagram 5] FIG. 11 is a block diagram showing an example of the configuration of a measurement system according to a second embodiment. [Figure 6] 10 is a flowchart showing an example of the operation of the measurement device according to the second embodiment. [Figure 7] 1A and 1B are graphs showing an example of a change in a judgment index over time and graphs showing an example of a time-series signal indicating a change in a signal value over time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] First embodiment A first embodiment will be described with reference to Figures 1 to 3. In the drawings, the same or similar elements are given the same reference numerals, and duplicated explanations will be omitted.

[0010] 1 is a block diagram showing an example of the configuration of a measurement system 1 according to this embodiment. The measurement system 1 includes a measurement device 100 and an information processing device 120.

[0011] The measuring device 100 emits light and measures the light transmitted through or reflected by the living body 110. The information processing device 120 calculates biological information indicating the state of blood vessels inside the skin of the living body 110 based on the measurement results of the measuring device 100. Specifically, the information processing device 120 calculates the biological information from the time change of the signal value acquired and adopted by the measuring device 100. For example, the information processing device 120 is a PC (Personal Computer), a tablet terminal, a terminal dedicated to calculating biological information, etc. The biological information is blood pressure, pulse, blood oxygen saturation, etc.

[0012] The measuring device 100 includes a light emitting unit 101 , a light receiving unit 102 , a control unit 103 , an output unit 104 , and a storage unit 105 .

[0013] The light emitting unit 101 irradiates light onto an exposed part of the skin of the living body 110. The exposed part of the skin of the living body 110 is, for example, a finger of the living body 110. For example, the light emitting unit 101 is configured with an LED (Light Emitting Diode) having at least three colors of R (Red), G (Green), and B (Blue). The light emitting unit 101 may be configured with a single LED that emits light of three wavelengths, or may be configured with three LEDs that emit light of each of the three wavelengths.

[0014] The light receiving unit 102 measures the intensity of light transmitted through the living body 110 or reflected by the living body 110, and is configured with a photodiode equipped with a color filter. For example, the light receiving unit 102 is configured with a photodiode equipped with a color filter in an RGB Bayer arrangement. Alternatively, the light receiving unit 102 may be configured with a photodiode equipped with a color filter such as RGBCy, RGBIR, etc.

[0015] The light emitting unit 101 and the light receiving unit 102 are placed at positions where the exposed skin of the living body 110 can be measured.

[0016] The control unit 103 controls the entire measuring device 100 and executes various processes according to the programs and data stored in the storage unit 105. The control unit 103 is configured with a processor such as a CPU (Central Processing Unit) and a GPU (Graphic Processing Unit). The control unit 103 includes a signal acquisition unit 111, a color information acquisition unit 112, a color information determination unit 113, and a signal correction unit 114.

[0017] The signal acquisition unit 111 acquires a signal value 121 indicating the intensity of light transmitted through or reflected by the living body 110.

[0018] The color information acquisition unit 112 converts the signal value 121 into color information. The color information indicates values ​​of a plurality of color elements. Specifically, the color elements are elements that constitute at least one of a color space and a color system. The color information acquisition unit 112 then calculates a judgment index 122 from the color information. Specifically, the color information acquisition unit 112 calculates the judgment index 122 from the difference between the value indicated by the color information and a reference value.

[0019] The color information determination unit 113 determines whether or not the color information satisfies a determination condition that the determination index 122 is equal to or smaller than the color gamut threshold.

[0020] The signal correction unit 114 employs a signal value 121 that can be converted into color information that satisfies the determination condition.

[0021] The output unit 104 outputs the signal value 121 adopted by the signal correction unit 114. Alternatively, the output unit 104 outputs a time-series signal constituted of the signal value 121 adopted by the signal correction unit 114. Alternatively, the output unit 104 outputs the determination result of the color information determination unit 113.

[0022] The storage unit 105 is a recording medium capable of recording various data, programs, etc., and is configured with a hard disk, an SSD (Solid State Drive), a semiconductor memory, etc. The storage unit 105 includes a measurement information storage unit 115 and a color information storage unit .

[0023] The measurement information storage unit 115 stores data within the condition, judgment OK data, a program stored in advance, information registered by the user, etc. For example, the user is the administrator of the living body 110 or the measuring device 100. The data within the condition indicates at least one of information indicating the time when the judgment condition is satisfied and the signal value 121 acquired at the time when the judgment condition is satisfied. The information indicating the time when the judgment condition is satisfied indicates the time when the judgment condition is satisfied, or identification information linked to the time when the judgment condition is satisfied. The judgment OK data indicates at least one of information indicating the time when the signal value 121 adopted by the signal correction unit 114 was acquired and the signal value 121 adopted by the signal correction unit 114.

[0024] Furthermore, a predetermined required number of pieces of data or a predetermined required time required to measure the biological information that is the measurement target is stored in the measurement information storage unit 115. The predetermined required number of pieces of data or the predetermined required time may be determined according to the biological information that is the measurement target.

[0025] The color information storage unit 116 stores color gamut thresholds, reference values, calculation formulas related to color information, calculation formulas related to judgment indices, judgment conditions, etc. The color gamut thresholds, reference values, etc. stored in the color information storage unit 116 can be changed by the user.

[0026] Furthermore, at least one of the measurement information storage unit 115 and the color information storage unit 116 stores information related to the living body 110, etc. As the information related to the living body 110, a log of the signal value 121, etc. is stored.

[0027] FIG. 2 is a flowchart showing an example of the operation of the measurement device 100 according to this embodiment.

[0028] In step S201, the measuring device 100 starts the measurement process. Specifically, when the measuring device 100 starts the measurement process, the light emitting unit 101 emits light, and the light is irradiated onto the exposed skin of the living body 110. The light receiving unit 102 receives the light transmitted through the living body 110 or the light reflected by the living body 110, and measures the intensity of the received light. In other words, the measuring device 100 can receive the light transmitted through the living body 110 or the light reflected by the living body 110 and measure the intensity of the received light by a simple and small light emitting element and light receiving element composed of an LED, a photodiode equipped with a color filter, or the like.

[0029] In step S202, the signal acquiring unit 111 acquires a signal value 121 indicating the intensity of light measured by the light receiving unit 102. Specifically, the signal value 121 indicates the intensity of light transmitted through or reflected by the living body 110. When the light emitting unit 101 is configured with an LED that emits light of three wavelengths of R, G, and B, the signal value 121 indicates a luminance value corresponding to R, G, and B.

[0030] Furthermore, the signal acquiring unit 111 may acquire a time-series signal indicating a time change of the signal value 121. For example, the signal acquiring unit 111 acquires a time-series signal indicating a time change of the signal value 121 at a predetermined time. Alternatively, the signal acquiring unit 111 acquires a time-series signal indicating a time change of the signal value 121 having a value within a predetermined range.

[0031] Also, for example, the signal acquiring unit 111 may calculate a signal indicating a pulse wave or absorbance from a time change of a value calculated by substituting the signal value 121 into a predetermined formula. The pulse wave indicates a change in the volume of a blood vessel, which is calculated from a time change of the brightness values ​​of R, G, and B. The absorbance is the optical density of a blood vessel, and is an index indicating the degree of light absorption by the blood vessel. For example, the signal acquiring unit 111 may calculate the absorbance according to the Beer-Lambert law. Alternatively, the signal acquiring unit 111 may acquire a time series signal of a value indicating biological information from a time change of the signal value 121 using an independent component analysis method, a pigment component separation method, or the like.

[0032] In step S203, the color information acquisition unit 112 converts the signal value 121 into color information to calculate the judgment index 122. The color information indicates values ​​of a plurality of color elements. The color elements are elements constituting at least one of a color space and a color system. Here, it is preferable that the color space and color system in the color information are a color space and color system that are less affected by the surrounding brightness than the RGB color space. For example, the color space in the color information into which the signal value 121 is converted is the HSL color space, the HSV color space, or the like. Alternatively, the color system in the color information into which the signal value 121 is converted is the L*C*h color system, the L*a*b color system, or the like.

[0033] The HSL color space indicates hue H, saturation S, and lightness L. That is, when the color information acquisition unit 112 converts the signal value 121 into color information using a conversion formula from the RGB color space to the HSL color space, the color information indicates a set of hue H, saturation S, and lightness L for an exposed part of the skin of the living body 110 to which the light emitted from the light emitting unit 101 is irradiated. The brightness and whitishness of the light can be expressed by the light luminance L and the saturation S.

[0034] The HSV color space indicates hue H, saturation S, and lightness V (Value). When the color information acquisition unit 112 converts the signal value 121 into color information using a conversion formula from the RGB color space to the HSV color space, the color information into which the signal value 121 is converted indicates a set of hue H, saturation S, and lightness V for an exposed part of the skin of the living body 110 to which light is irradiated by the light emitting unit 101. The lightness V and saturation S can express the brightness and whitishness of the light.

[0035] The L*C*h color system indicates lightness L, chroma C*, and hue h. In other words, when the color information acquisition unit 112 converts the signal value 121 into color information using a conversion formula from the RGB color space to the L*c*h color system, the color information into which the signal value 121 is converted indicates a set of lightness L, chroma C*, and hue h for the exposed skin of the living body 110 to which light is irradiated by the light emitting unit 101. The lightness L, chroma C*, and hue h can express the brightness and whitishness of the light.

[0036] The L*a*b color system indicates lightness L (Lightness), chromaticity a*, and chromaticity b*. The chromaticity a* and chromaticity b* indicate hue and saturation. In other words, when the color information acquisition unit 112 converts the signal value 121 into color information using a conversion formula from the RGB color space to the L*a*b color system, the color information into which the signal value 121 is converted indicates a set of lightness L, chromaticity a*, and chromaticity b* for the exposed skin of the living body 110 to which light is irradiated by the light emitting unit 101. The brightness and whitishness of light can be expressed by the lightness L, chromaticity a*, and chromaticity b*.

[0037] The brightness and whitishness of light expressed in the HSL color space, HSV color space, L*C*h color system, or L*a*b color system are caused by the light received by the light receiving unit 102 being significantly brighter due to an increase in diffuse reflected light and regular reflected light from the skin surface. Therefore, the significantly brighter received light due to an increase in diffuse reflected light and regular reflected light from the skin surface caused by roughness of the skin surface is not caused by the state of the blood vessels of the living body 110, but by the roughness of the skin surface. Therefore, the measuring device 100 can detect changes in the skin surface by analyzing the brightness and whitishness of light.

[0038] Since the brightness and whitishness of light can be expressed using the HSL color space, HSV color space, L*C*h color system, or L*a*b color system, the color information can express the brightness and whitishness of the exposed skin of the living body 110 to which the light emitted from the light-emitting unit 101 is irradiated.

[0039] Therefore, the color information acquisition unit 112 calculates the judgment index 122 from the difference between the value indicated by the color information and the reference value. The reference value is determined based on color information converted from the signal value 121 measured in advance. For example, the reference value indicates color information converted from the signal value 121 measured by the signal acquisition unit 111 when the subject of measurement, who is the living body 110, uses the measuring device 100 for the first time. Alternatively, the reference value may indicate color information converted from the signal value 121 measured by the signal acquisition unit 111 when the subject of measurement, who is the living body 110, is in good physical condition. In other words, the color information acquisition unit 112 stores a reference value indicating a reference state for the skin of each individual. Alternatively, the reference value may indicate color information converted from the signal value 121 measured by the signal acquisition unit 111 when the measurement environment is stable.

[0040] For example, it is assumed that the color information acquisition unit 112 converts the luminance values ​​corresponding to R, G, and B indicated by the signal value 121 into color information indicating the luminance L' using a conversion formula from the RGB color space to the HSV color space. Furthermore, it is assumed that a reference value L0 for the luminance L is stored in the color information storage unit 116. In this case, the color information acquisition unit 112 calculates the difference between the luminance L' and the reference value L0 (=L'-L0) as the judgment index 122.

[0041] For example, when the measurement device 100 is equipped with a light-shielding cover and the measurement environment can eliminate the influence of the lighting around the measurement device 100, the difference between the luminance L' and the reference value L0 (=L'-L0) is calculated as the judgment index 122 for the luminance L.

[0042] Also, for example, it is assumed that a reference value L0 for luminance L and a reference value S0 for saturation S are stored in the color information storage unit 116. In this case, the color information acquisition unit 112 calculates, as the judgment index 122, the difference between the luminance L' and the reference value L0 (=L'-L0) and the difference between the saturation S' and the reference value S0 (=S'-S0).

[0043] Furthermore, the color information acquisition unit 112 may determine that the lighting environment has changed when the amount of change in the signal value 121 within a predetermined time exceeds a threshold. Then, when the color information acquisition unit 112 determines that the lighting environment has changed, the color information acquisition unit 112 may change the calculation formula for the determination index 122. For example, when the color information acquisition unit 112 determines that the lighting environment has not changed, the color information acquisition unit 112 calculates the difference between the luminance L' and the reference value L0 (=L'-L0) as the determination index 122. On the other hand, when the color information acquisition unit 112 determines that the lighting environment has changed, the color information acquisition unit 112 may calculate the difference between the luminance L' and the reference value L0 (=L'-L0) and the difference between the saturation S' and the reference value S0 (=S'-S0) as the determination index 122.

[0044] For example, the color information acquisition unit 112 calculates the judgment index 122 each time the signal value 121 is acquired in step S202. Alternatively, the color information acquisition unit 112 may calculate the judgment index 122 each time the signal value 121 is acquired a predetermined number of times. Alternatively, the color information acquisition unit 112 may convert the average value of the signal values ​​acquired the predetermined number of times into color information to calculate the judgment index 122. For example, the predetermined number of times is three times. Note that, by the color information acquisition unit 112 calculating the judgment index 122 each time the signal value 121 is acquired in step S202, the time change in the intensity of the light received by the light receiving unit 102 can be obtained in detail and with high accuracy, which is preferable.

[0045] In step S204, the color information determination unit 113 determines whether the determination index 122 satisfies the determination condition. The determination condition is that the determination index 122 is less than the color gamut threshold. For example, the color gamut threshold is determined according to the type of biological information. For example, the color gamut threshold in the case where the type of biological information for the measurement purpose is pulse may be different from the color gamut threshold in the case where the type of biological information for the measurement purpose is blood pressure.

[0046] For example, assume that in step S203, the color information acquisition unit 112 calculates the difference (=L'-L0) between the luminance L' and the reference value L0 as the determination index 122. Further, assume that the color gamut threshold Lth for the luminance L is stored in the color information storage unit 116. And assume that the determination condition is L'-L0 < Lth. In that case, the color information determination unit 113 determines whether L'-L0 < Lth. The fact that the determination condition is not satisfied, that is, L'-L0 < Lth, indicates that the color information is greater than or equal to the color gamut threshold than the reference value. The fact that the color information is greater than or equal to the color gamut threshold than the reference value is considered to be correlated with the phenomenon that the light received by the light receiving unit 102 becomes brighter or whiter due to the increase in the diffuse reflection light and the specular reflection light due to the rough surface of the skin.

[0047] The determination condition may be related to at least one of a plurality of color spaces and a plurality of color systems. For example, the determination condition may be that the determination index 122 is less than the color gamut threshold RGth for the RGB color space and the determination index 122 is less than the color gamut threshold Lth for the luminance L. In that case, assume that the color gamut threshold Lth for the luminance L and the color gamut threshold RGth for the RGB color interval are stored in the color information storage unit 116. Further, in that case, the determination index 122 indicates the value for the RGB color space and the value for the HSL color space.

[0048] For example, the color information acquisition unit 112 calculates the difference between the luminance L' and the reference value L0 (=L' - L0) as the determination index 122, and also calculates the difference between the luminance value R' corresponding to R and the luminance value G' corresponding to G (=R' - G'). The luminance value R' corresponding to R is the luminance value corresponding to R indicated by the signal value 121, and the luminance value G' corresponding to G is the luminance value corresponding to G indicated by the signal value 121. In that case, it is assumed that the determination conditions are L' - L0 < Lth and R' - G' < RGth.

[0049] When the color information determination unit 113 determines whether the determination index 122 satisfies the determination conditions for a plurality of color spaces, a more detailed determination can be made than when determining whether the determination conditions for one color space are satisfied.

[0050] Note that depending on the performance of the light emitting unit 101, the performance of the light receiving unit 102, the illumination around the measuring device 100, and the state of the skin of the living body 110, the signal value 121 that enables appropriate measurement of the biological information can be different. Therefore, it is preferable to set the color gamut threshold according to the performance of the light emitting unit 101, the performance of the light receiving unit 102, the illumination around the measuring device 100, and the state of the skin of the living body 110.

[0051] The plurality of color elements corresponding to the value indicated by the color information and the reference value are determined according to the type of biological information that is the measurement purpose. That is, the color space used to calculate the color information, the color system used to calculate the color information, and the reference value may be determined according to the type of biological information that is the measurement purpose.

[0052] Referring to FIG. 3, the time change of the determination index 122 will be described.

[0053] FIG. 3 is a diagram showing the color gamut threshold and a graph showing an example of the time change of the determination index 122. In FIG. 3, time is taken on the horizontal axis and the determination index is taken on the vertical axis. Each point illustrated in FIG. 3 indicates the value of the determination index calculated based on the signal value 121 acquired at different time points.

[0054] For example, the determination index 122 from time t312 to time t313 and after time t316 has a value equal to or greater than the color gamut threshold. This is because, from time t312 to t313 and after time t316, the light received by the light receiving unit 102 becomes significantly brighter or whitish due to an increase in diffuse reflected light and regular reflected light from the skin surface caused by the roughness of the skin surface. Therefore, the measurement device 100 can identify the time point at which the diffuse reflected light and regular reflected light from the skin surface increased due to the roughness of the skin surface by determining whether the determination index 122 is less than the color gamut threshold.

[0055] Furthermore, the intensity of light that passes through the skin of the living body 110 or is reflected by the skin of the living body 110 and is received by the light receiving unit 102 depends on the condition of the skin of the individual and differs from person to person. However, since the color information storage unit 116 stores a reference value for each individual living body 110, the measurement device 100 can use the reference value set for each individual living body 110 to identify the time point at which the diffuse reflected light and specular reflected light from the skin surface due to roughness of the skin surface increased for each individual living body 110.

[0056] Referring again to FIG. 2, the operation of the measurement device 100 will continue.

[0057] If the judgment index 122 does not satisfy the judgment condition in step S204, the control unit 103 transfers the process to step S206.

[0058] On the other hand, if the judgment index 122 satisfies the judgment condition in step S204, in step S205 the color information judgment unit 113 stores information indicating the time point at which the judgment index 122 satisfies the judgment condition as within-condition data in the measurement information storage unit 115. Alternatively, the color information judgment unit 113 stores the signal value 121 acquired at the time point at which the judgment index 122 satisfies the judgment condition as within-condition data in the measurement information storage unit 115. Then, the control unit 103 transitions the process to step S206.

[0059] In step S206, the color information determination unit 113 determines whether the within-condition data continues for a period equal to or greater than the section threshold. That is, the color information determination unit 113 determines whether the time-series signal values ​​121 acquired by the signal acquisition unit 111 can be converted into color information that satisfies the determination condition for a period equal to or greater than the section threshold.

[0060] For example, the section threshold is the number of judgment indicators 122. Note that successive calculation of a predetermined number of judgment indicators 122 is synonymous with the time required to obtain successive judgment indicators 122 being a predetermined time. Therefore, the section threshold may be a predetermined time. For example, the section threshold is determined according to the type of biometric information.

[0061] If the within-condition data does not continue for a period of time that is equal to or greater than the section threshold in step S206, the control unit 103 returns the process to step S202. If the period of time that the within-condition data is not equal to or greater than the section threshold is repeated a predetermined number of times or more, the color information determination unit 113 causes the output unit 104 to output a message to alert the living body 110. For example, the output unit 104 may cause a display (not shown) connected to the measurement device 100 to display text indicating a message to alert the living body 110. Alternatively, the output unit 104 may cause a speaker (not shown) connected to the measurement device 100 to output audio indicating a message to alert the living body 110.

[0062] For example, suppose that the living body 110 places a finger of the living body 110 on the measuring device 100, and light emitted from the light emitting unit 101 is irradiated onto the finger of the living body 110. In this case, the output unit 104 outputs a message indicating an instruction to reposition the finger. Alternatively, the message output by the output unit 104 may be a message indicating an instruction to place a different finger on the measuring device 100.

[0063] On the other hand, if the within-condition data continues for a period equal to or greater than the section threshold in step S206, in step S207, the signal correction unit 114 stores the within-condition data that continues for a period equal to or greater than the section threshold as judgment OK data in the measurement information storage unit 115. In other words, the signal correction unit 114 adopts the signal value 121 that continues for a period equal to or greater than the section threshold and that can be converted into color information that satisfies the judgment condition.

[0064] The OK judgment data will be described with reference to Fig. 3 again. In the following description, it is assumed that the section threshold is set such that the number of judgment indicators 122 is four.

[0065] 3, the judgment index 122 is equal to or less than the color gamut threshold, so the judgment index 122 satisfies the judgment condition from time t314 to time t315. In this case, the number of judgment indexes 122 from time t314 to time t315 is three, so the number of judgment indexes 122 from time t314 to time t315 is less than the section threshold. Therefore, the measurement information storage unit 115 does not store judgment OK data from time t314 to time t315.

[0066] On the other hand, from time t310 to time t311, the judgment indicators 122 are less than or equal to the color gamut threshold, and the number of judgment indicators 122 is five from time t310 to time t311. Therefore, from time t310 to time t311, the judgment indicators 122 satisfy the judgment condition, and the number of judgment indicators 122 is greater than or equal to the section threshold. Therefore, the measurement information storage unit 115 stores judgment OK data from time t310 to time t11.

[0067] The waveform composed of the time-series signal values ​​121 reflects the time change indicating the pulsation of the blood vessels of the living body 110. In other words, the waveform composed of the time-series signal values ​​121 reflects the biological information of the living body 110. However, the intensity of the light transmitted through or reflected by the living body 110 varies over time due to body movement, and may change due to specular reflection light or diffuse reflection light. Therefore, in the process of step S207, the signal correction unit 114 does not store in-condition data that is not continuous for a period equal to or greater than the section threshold as judgment OK data in the measurement information storage unit 115. In other words, the measurement device 100 excludes the signal values ​​121 that are not continuous for a period equal to or greater than the section threshold.

[0068] In step S208, the signal correction unit 114 determines whether or not necessary judgment OK data has been acquired. Specifically, the signal correction unit 114 determines whether or not judgment OK data for a predetermined required number of data or a predetermined required time stored in the measurement information storage unit 115 has been acquired.

[0069] If the necessary judgment OK data is not acquired in step S208, the control unit 103 returns the process to S202. On the other hand, if the necessary judgment OK data is acquired in step S208, the signal correction unit 114 in step S209 adopts data corresponding to the time point of the judgment OK data stored in the measurement information storage unit 115. For example, when the signal acquisition unit 111 acquires a signal composed of a time-series signal value 121, the signal correction unit 114 extracts data corresponding to the time point of the judgment OK data from the acquired signal. Alternatively, when a signal is generated by data corresponding to the time point of the judgment OK data, the signal correction unit 114 may adopt the generated signal.

[0070] In step S210, the output unit 104 outputs the adopted data. Furthermore, the output unit 104 may output information necessary for calculating the biological information to be measured. Then, the information processing device 120 calculates the biological information from the time change of the signal value 121 adopted by the signal correction unit 114.

[0071] That is, in the process of step S207, the signal correction unit 114 stores within-condition data that continues for a period equal to or greater than the section threshold as judgment OK data in the measurement information storage unit 115. Then, in step S210, the output unit 104 outputs data corresponding to the time point of the judgment OK data stored in the measurement information storage unit 115. In this way, the information processing device 120 calculates bioinformation from the time change of the signal value 121 that is suitable for calculating bioinformation and continues for a period equal to or greater than the section threshold.

[0072] As described above, the measuring device 100 according to this embodiment excludes the signal value 121 indicating a significant change in light due to a change in the condition of the skin surface of the living body 110 from the signal value 121 used to calculate the biological information. In other words, the measuring device 100 according to this embodiment does not adopt the signal value 121 acquired by irradiating light onto a part of the skin surface of the living body 110 where the skin surface is rough. The measuring device 100 according to this embodiment adopts the signal value 121 acquired by irradiating light onto a part of the skin surface where the skin surface is not rough, which is suitable for measuring the biological information. This allows the information processing device 120 to accurately calculate the biological information from the signal value 121 acquired by irradiating light onto a part of the skin surface where the skin surface is not rough.

[0073] (Modification of the first embodiment) A modified example of the first embodiment will be described with reference to Fig. 4. In the drawings, the same or similar elements are given the same reference numerals, and duplicated explanations will be omitted.

[0074] The difference between the measurement device 100 according to this modification and the measurement device 100 according to the first embodiment is that the measurement device 100 according to this modification does not use a section threshold value, but adopts data that satisfies the judgment condition. In other words, the signal correction unit 114 according to this modification adopts the signal value 121 that can be converted into color information that satisfies the judgment condition, from among the time-series signal values ​​acquired by the signal acquisition unit 111.

[0075] Fig. 4 is a flowchart showing an example of the operation of the measurement device 100 according to this modification. The processes from step S401 to step S405 are similar to the processes from step S201 to step S205 shown in Fig. 2, and therefore detailed description thereof will be omitted.

[0076] In step S406, the signal correction unit 114 determines whether or not data within the required conditions has been acquired. Specifically, the signal correction unit 114 determines whether or not data within the conditions of a predetermined required number of data or a predetermined required time stored in the measurement information storage unit 115 has been acquired.

[0077] If the necessary within-condition data has not been acquired in step S406, the control unit 103 returns the process to S402. On the other hand, if the necessary within-condition data has been acquired in step S406, the signal correction unit 114 employs data at a time point corresponding to the within-condition data stored in the measurement information storage unit 115 in step S407. This allows the measurement device 100 according to this modification to employ more data than the measurement device 100 according to the first embodiment. Furthermore, since the measurement device 100 according to this modification does not require a continuous period of time in which the within-condition data is equal to or greater than the section threshold, the measurement time required for measurement can be shorter than that of the measurement device 100 according to the first embodiment.

[0078] Second Embodiment The second embodiment will be described with reference to Figures 5 to 7. In the drawings, the same or similar elements are given the same reference numerals, and duplicated explanations will be omitted.

[0079] Fig. 5 is a block diagram showing an example of the configuration of the measurement system 1 according to this embodiment. The difference between the measurement system 1 shown in Fig. 5 and the measurement system 1 shown in Fig. 1 is that the measurement device 100 included in the measurement system 1 shown in Fig. 5 includes a cycle extraction unit 501.

[0080] The cycle extraction section 501 extracts a pulse signal 511 that constitutes a period from a time-series signal that indicates the change over time of the signal value 121 .

[0081] The color information acquisition unit 112 according to this embodiment converts each of the multiple signal values ​​121 that make up the pulse signal 511 into color information.

[0082] The signal correction unit 114 according to this embodiment employs a pulse signal 511 that is made up of a signal value 121 that can be converted into color information that satisfies a judgment condition.

[0083] The output unit 104 according to the present embodiment outputs a signal value 121 constituting the pulse signal 511 adopted by the signal correction unit 114. Alternatively, the output unit 104 outputs a time-series signal constituted by the pulse signal adopted by the signal correction unit 114.

[0084] The measurement information storage unit 115 according to this embodiment further stores out-of-condition data and within-condition pulses. The out-of-condition data indicates at least one of information indicating a time point where the judgment condition is not satisfied and the signal value 121 acquired at the time point where the judgment condition is not satisfied. The information indicating a time point where the judgment condition is not satisfied indicates at least one of a time and identification information linked to the time point. The within-condition pulse indicates a pulse signal 511 composed only of the time point of the within-condition data.

[0085] Furthermore, the measurement information storage unit 115 according to the present embodiment stores a predetermined required number of pulses or a predetermined required time required to measure the biological information to be measured. The predetermined required number of pulses or the predetermined required time may be determined according to the type of the biological information to be measured.

[0086] Fig. 6 is a flowchart showing an example of the operation of the measurement device 100 according to this embodiment. The process of step S601 is similar to the process of step S201 illustrated in Fig. 2, and therefore a detailed description thereof will be omitted.

[0087] In step S602, the signal acquiring unit 111 acquires a signal value 121 indicating the intensity of light measured by the light receiving unit 102. The signal acquiring unit 111 may calculate the sum or product of values ​​obtained by multiplying the luminance values ​​of R, G, and B indicated by the signal value 121 by a predetermined coefficient. Then, the signal acquiring unit 111 acquires a time-series signal indicating the change in the signal value 121 over time.

[0088] Alternatively, the signal acquiring unit 111 may calculate an absorbance signal and a pulse wave signal from a time change in a value calculated by substituting the signal value 121 into a predetermined formula. Alternatively, the signal acquiring unit 111 may acquire a time series signal of a value indicating biological information from the time change in the signal value 121 using an independent component analysis method, a pigment component separation method, or the like.

[0089] For example, the heart of the living body 110 repeats contraction and expansion, so that the blood vessels pulsate. When the signal value 121 indicates the pulsation of the blood vessels, the signal value 121 repeats increasing and decreasing according to the pulsation cycle. Similarly, the breathing of the living body 110 has periodicity, so when the signal value 121 indicates the breathing movement, the signal value 121 repeats increasing and decreasing. That is, the life activity has periodicity, and the cycle indicated by the periodicity reflects the health state of the living body 110. Therefore, when measuring biological information having periodicity, the health state of the living body 110 can be analyzed with high accuracy by dividing the time series signal into periods and analyzing each pulse extracted. Therefore, in the measurement device 100 according to this embodiment, the section of the data to be used is divided into predetermined cycles.

[0090] Therefore, in step S603, the cycle extraction unit 501 extracts a pulse signal 511 from the time series signal acquired in step S602. Specifically, the cycle extraction unit 501 extracts a section that satisfies the pulse extraction condition from the time series signal as a pulse signal 511 for each cycle. Note that the section indicating the cycle is set according to the biological information to be measured.

[0091] For example, assume that the time series signal indicates a pulse wave signal, and the type of biological information to be measured is heart rate or blood pressure. In this case, the section from the rising edge to the falling edge of the pulse wave signal accompanying contraction and expansion of the signal is set as one cycle. Then, cycle extraction unit 501 stores at least one of information indicating the time point when signal value 121 constituting pulse signal 511 was acquired and signal value 121 constituting pulse signal 511 in measurement information storage unit 115.

[0092] In step S604, the color information acquisition unit 112 converts the multiple signal values ​​121 constituting the pulse signal 511 into color information to calculate multiple judgment indexes 122. The process of converting the signal values ​​121 into color information and calculating the judgment indexes 122 in step S604 is similar to the process of step S203 illustrated in FIG. 2, and therefore a detailed description thereof will be omitted.

[0093] In step S605, the color information determination unit 113 determines whether or not at least one of the multiple determination indexes 122 calculated in step S604 satisfies the determination condition. Specifically, the color information determination unit 113 determines whether or not each of the multiple determination indexes 122 satisfies the determination condition. In step S605, the process of determining whether or not each determination index 122 satisfies the determination condition is similar to the process of step S204 illustrated in FIG. 2, and therefore detailed description thereof will be omitted.

[0094] If none of the judgment indicators 122 satisfy the judgment condition in step S605, the control unit 103 moves the process to step S608. On the other hand, if at least one of the judgment indicators 122 satisfies the judgment condition in step S605, the color information judgment unit 113 stores information indicating the time point at which the judgment indicator 122 does not satisfy the judgment condition in the measurement information storage unit 115 as out-of-condition data in step S606, and stores information indicating the time point at which the judgment indicator 122 satisfies the judgment condition in the measurement information storage unit 115 as out-of-condition data.

[0095] In step S607, the color information determination unit 113 stores the pulse signal 511 including only the time points of the within-condition data as an within-condition pulse in the measurement information storage unit 115. In other words, the color information determination unit 113 does not store the pulse signal 511 including the out-of-condition data in the measurement information storage unit 115 as an within-condition pulse.

[0096] In step S608, the signal correction unit 114 determines whether or not a pulse within the required condition has been acquired. Specifically, the signal correction unit 114 determines whether or not a pulse signal 511 of a predetermined required number of pulses or a predetermined required time stored in the measurement information storage unit 115 has been acquired.

[0097] If the necessary satisfying pulse has not been acquired in step S608, control unit 103 returns the process to step S602. On the other hand, if the necessary satisfying pulse has been acquired in step S609, signal correction unit 114 in step S606 employs data corresponding to the time of the satisfying pulse stored in measurement information storage unit 115. In other words, signal correction unit 114 does not employ pulse signal 511 including unsatisfactory data, but employs only good quality pulses with a complete cycle of data.

[0098] The signal correction unit 114 may also determine whether or not the within-condition pulse continues for a period of a predetermined number of times or more. In other words, the signal correction unit 114 determines whether or not the pulse signal 511 including only the time points of the within-condition data continues for a period of a predetermined number of times or more. By the measurement device 100 employing the temporally continuous pulse signal 511, the information processing device 120 can calculate biological information from the temporally continuous pulse signal 511.

[0099] In step S610, the output unit 104 outputs the adopted data. Furthermore, the output unit 104 may output information necessary for calculating the biological information that is the measurement target.

[0100] The process of extracting the pulse signal 511 will now be described in detail with reference to FIG.

[0101] FIG. 7 is a graph showing an example of a change over time of the judgment index 122 and a graph showing an example of a time-series signal indicating a change over time of the signal value 121. In FIG.

[0102] The upper diagram of FIG. 7 is a diagram showing a color gamut threshold and a graph showing an example of a time change in the judgment index 122. In the upper diagram of FIG. 7, the horizontal axis represents time, and the vertical axis represents the judgment index. In the upper diagram of FIG. 7, each point shown in the graph represents the value of the judgment index 122 acquired at a different time point. The lower diagram of FIG. 7 is a graph showing an example of a time-series signal indicating a time change in the signal value 121. In the lower diagram of FIG. 7, the horizontal axis represents time, and the vertical axis represents the value of the time-series signal. For example, when the time-series signal shown in FIG. 7 represents a pulse wave signal, the vertical axis of FIG. 7 represents the intensity of the pulse wave.

[0103] 7 correspond in time. That is, the same value on the horizontal axis of the upper diagram and the horizontal axis of the lower diagram of FIG. 7 indicate the same time point. For the sake of explanation, the acquisition interval of the determination index 122 in the upper diagram of FIG. 6 is shown to be coarser than the measurement interval of the time-series signal in the lower diagram of FIG. 6. However, for example, when the time-series signal illustrated in the lower diagram of FIG. 6 indicates a pulse wave signal, it is preferable that the acquisition interval of the determination index 122 is approximately the same as the measurement interval of the time-series signal in the lower diagram of FIG. 6.

[0104] 6, interval tA to interval tE indicate cycles of increase and decrease of the signal value 121. Therefore, the cycle extraction unit 501 divides the time-series signal acquired in step S602 into intervals tA to tE, and extracts a pulse signal 511 for each of intervals tA to tE.

[0105] For example, the judgment index 122 is equal to or greater than the color gamut threshold at time t610 and time t613. In other words, the judgment index 122 does not satisfy the judgment condition at time t610 and time t613. Therefore, the color information judgment unit 113 does not store the pulse signal 511 in the section tA including the time t610 and the section tE including the time t613 in the measurement information storage unit 115 as a pulse within the condition.

[0106] On the other hand, in the period from time t611 to time t612, all of the judgment indicators 122 are less than the color gamut threshold. That is, in the period from time t611 to time t612, all of the judgment indicators 122 satisfy the judgment condition. Therefore, the color information judgment unit 113 stores the pulse signal 511 in the section tB to section tD, which is the section corresponding to time t611 to time t612, in the measurement information storage unit 115 as a pulse that meets the condition. In this way, the color information judgment unit 113 can store only good-quality pulses in which one cycle of data is completely complete, in the measurement information storage unit 115 as a pulse that meets the condition.

[0107] The processes executed in the above embodiments are not limited to the process modes exemplified in the above embodiments. The above-mentioned functional blocks may be realized using either a logic circuit (hardware) formed in an integrated circuit or the like, or software using a CPU. The above implementation may be executed by multiple computers. For example, the processes executed in each functional block of the control unit 103 of the measuring device 100 may be partially executed by another computer, or all of the processes may be shared and executed by multiple computers.

[0108] The present disclosure is not limited to the above-mentioned embodiment, and may be replaced with a configuration substantially the same as the configuration shown in the above-mentioned embodiment, a configuration having the same action and effect, or a configuration capable of achieving the same purpose. The present disclosure also includes embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Furthermore, by combining the technical means disclosed in each embodiment, a new technical feature can be formed. [Explanation of symbols]

[0109] 1 Measurement system, 100 Measurement device, 101 Light emitting unit, 102 Light receiving unit, 103 Control unit, 104 Output unit, 105 Memory unit, 110 Living body, 111 Signal acquisition unit, 112 Color information acquisition unit, 113 Color information judgment unit, 114 Signal correction unit, 115 Measurement information memory unit, 116 Color information memory unit, 120 Information processing device, 121 Signal value, 122 Judgment index, 501 Cycle extraction unit, 511 Pulse signal

Claims

1. A signal acquiring unit that acquires a signal value indicating the intensity of light transmitted through or reflected by a living body; a color information acquisition unit that converts the signal value into color information; a color information determination unit that determines whether the color information satisfies a determination condition; a signal correction unit that adopts a signal value that can be converted into color information that satisfies the determination condition; A measuring device comprising:

2. The signal correction unit adopts a signal value that continues for a period of time equal to or greater than a section threshold value and that can be converted into color information that satisfies the judgment condition.

2. The measuring device of claim 1.

3. The color information acquisition unit calculates a judgment index from the color information, The judgment condition is that the judgment index is less than a color gamut threshold.

3. The measuring device according to claim 1 or 2.

4. the color information indicates values ​​of a plurality of color elements; The color information acquisition unit calculates the judgment index from a difference between a value indicated by the color information and a reference value.

3. The measuring device according to claim 1 or 2.

5. a cycle extraction unit that extracts a pulse signal constituting a period from a time-series signal indicating a time change in the signal value; Further equipped with The color information acquisition unit converts each of a plurality of signal values ​​constituting the pulse signal into the color information.

3. The measuring device according to claim 1 or 2.

6. The signal correction unit employs a pulse signal that is configured with a signal value that can be converted into color information that satisfies the judgment condition.

6. The measuring device according to claim 5.

7. A measuring device according to claim 1 ; an information processing device that calculates biological information from a time change of the signal value adopted by the signal correction unit; A measurement system including:

8. The color information acquisition unit calculates a value of a judgment index from the color information, the judgment condition is that the value of the judgment index is less than a color gamut threshold; The color gamut threshold is determined according to the type of the biometric information. The measurement system of claim 7.

9. the signal correction unit adopts a signal value that continues for a period of time equal to or greater than a section threshold value to indicate that the signal value can be converted into color information that satisfies the determination condition; The section threshold is determined according to the type of the biological information. The measurement system of claim 7.

10. the color information indicates values ​​of a plurality of color elements; the color information acquisition unit calculates the value of the judgment index from a difference between a value indicated by the color information and a reference value; The plurality of color elements and the reference value are determined according to the type of the biometric information.

8. The measuring device according to claim 7.

11. acquiring a signal value indicating the intensity of light transmitted through or reflected by the living body; converting the signal values ​​into color information; determining whether the color information satisfies a determination condition; adopting a signal value that can be converted into color information that satisfies the judgment condition; Measurement methods including:

Images