Detection device and measuring device

Abstract

To provide a detection apparatus and a measurement apparatus capable of downsizing a device constitution.SOLUTION: The detection device comprises: a first light emitting part which emits first light with a green wavelength band; a second light emitting part which emits second light with a wavelength band higher than the green wavelength band; a first light receiving part which receives the first light emitted from the first light emitting part and ejected from a living body; and a second light receiving part which receives the second light emitted from the second light emitting part and ejected from the living body. The first light receiving part includes a band pass filter selectively transmits therethrough the light with the green wavelength band and the distance from the first light emitting part to the first light receiving part is shorter than the distance from the second light emitting part to the second light receiving part.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a detection device and a measuring device.

Background Art

[0002] Various measurement techniques for non-invasively measuring biological information such as pulse waves have been proposed conventionally. For example, in Patent Document 1 below, in a detection device including a light emitting unit that emits light to a living body and a light receiving unit that receives light that is emitted from the light emitting unit and enters by being reflected by the living body, a technique is disclosed in which a light shielding member is installed between the light emitting unit and the light receiving unit to improve the light utilization efficiency of the light emitting unit and to prevent stray light in the light receiving unit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the above detection device, since it is necessary to provide a thick light shielding member between a plurality of light receiving units, there is a problem that the device configuration cannot be miniaturized.

Means for Solving the Problems

[0005] According to one aspect of the present invention, a first light-emitting unit emits first light having a green wavelength band toward a living organism; a second light-emitting unit is provided so as to be aligned with the first light-emitting unit in a first direction and emits second light having a higher wavelength band than the green wavelength band toward the living organism; a first light-receiving unit receives the first light emitted from the first light-emitting unit and propagating within the living organism; a second light-receiving unit is provided so as to be aligned with the first light-receiving unit in a second direction intersecting the first direction and receives the second light emitted from the second light-emitting unit and propagating within the living organism; and a first region housing the first light-emitting unit and the second light-emitting unit. A case portion having a bottom surface portion including a region and a second region housing the first light-receiving portion and the second light-receiving portion; a first sealing member filling the first region and sealing the first light-emitting portion and the second light-emitting portion; a second sealing member filling the second region and sealing the first light-receiving portion and the second light-receiving portion, wherein the case portion has a light-shielding wall provided between the first sealing member and the second sealing member in the second direction, and the light-shielding wall protrudes from the bottom surface portion along a third direction perpendicular to the first and second directions so as to separate the first sealing member and the second sealing member. The light-shielding wall extends along the first direction and has thickness in the second direction, The surface of the second sealing member is a plane perpendicular to an axis along the third direction, and the first light receiving unit includes a bandpass filter that selectively transmits the first light from the first light and the second light incident from the surface of the second sealing member, a first angle limiting filter that selectively transmits the first light incident at an angle smaller than a predetermined incident angle from the first light that has passed through the bandpass filter, and a first sensor that receives the first light that has passed through the first angle limiting filter, wherein the first angle limiting filter is provided between the first sensor and the bandpass filter in the third direction, and the second light receiving unit is the 2 A second angle limiting filter that selectively transmits the second light incident at an angle smaller than a predetermined incident angle from the surface of the sealing member, and a second angle limiting filter that receives the second light that has passed through the second angle limiting filter. 2The sensor includes, and the second light receiving unit does not include a bandpass filter that selectively transmits the second light, the distance from the first light emitting unit to the first light receiving unit is shorter than the distance from the second light emitting unit to the second light receiving unit, and in the second region of the case, the second direction in The aforementioned The The detection device is provided in which there is no light-shielding wall between the first light-receiving unit and the second light-receiving unit.

[0006] According to one aspect of the present invention, a detection device is provided comprising: a first light-emitting unit that emits first light having a green wavelength band; a second light-emitting unit that emits second light having a wavelength band higher than the green wavelength band; a first light-receiving unit that receives the first light emitted from the first light-emitting unit and emitted from a living organism; and a second light-receiving unit that receives the second light emitted from the second light-emitting unit and emitted from the living organism, wherein the distance from the first light-emitting unit to the first light-receiving unit is shorter than the distance from the second light-emitting unit to the second light-receiving unit; the first light-receiving unit includes a bandpass filter that selectively transmits the first light; and the second light-receiving unit does not include a bandpass filter that selectively transmits the second light.

[0007] According to one aspect of the present invention, a measuring device is provided that comprises a detection device according to the above-described embodiment and an information analysis unit that identifies biological information from a detection signal indicating the detection result by the detection device. [Brief explanation of the drawing]

[0008] [Figure 1] This is a side view of the measuring device according to the first embodiment. [Figure 2] This is a diagram showing the configuration of the measuring device, focusing on its functions. [Figure 3] This is a plan view of the detection device. [Figure 4] Figure 3 is a cross-sectional view taken along the line IV-IV. [Figure 5] This graph shows the skin's transmission spectrum. [Figure 6] This is a diagram illustrating the operation of the detection device. [Figure 7]This is a plan view of the detection device of the second embodiment. [Figure 8] This is a cross-sectional view taken along the line VIII-VIII in Figure 7. [Modes for carrying out the invention]

[0009] The following describes one embodiment of the present invention with reference to the drawings. In the following drawings, the scale and angles of each component have been altered from those of the actual components in order to make them recognizable.

[0010] (First Embodiment) Figure 1 is a side view of the measuring device 100 of the first embodiment. The measuring device 100 of this embodiment shown in Figure 1 is a biomechanical measuring device that non-invasively measures biological information of a subject (e.g., a human), which is an example of a living organism, and is attached to the part of the subject's body to be measured (hereinafter referred to as the "measurement site") M. The measuring device 100 of this embodiment is a wristwatch-type portable device comprising a housing 1 and a belt 2, and can be attached to the subject's wrist by wrapping the belt-shaped belt 2 around the wrist, which is an example of the measurement site (living organism) M. In this embodiment, the subject's pulse wave (e.g., pulse rate) and oxygen saturation (SpO2) are used as examples of biological information. A pulse wave refers to the time change in the volume inside the blood vessels in conjunction with the beating of the heart. Oxygen saturation refers to the percentage (%) of hemoglobin in the subject's blood that is bound to oxygen, and is an index for evaluating the subject's respiratory function.

[0011] Figure 2 is a configuration diagram focusing on the functions of the measuring device 100. As shown in Figure 2, the measuring device 100 of this embodiment includes a control device 5, a storage device 6, a display device 4, and a detection device 3. The control device 5 and the storage device 6 are installed inside the housing 1. As shown in Figure 1, the display device 4 is installed on the surface of the housing 1 opposite to the measurement area M, and displays various images, including measurement results, under the control of the control device 5. The display device 4 is, for example, a liquid crystal display panel.

[0012] The detection device 3 is an optical sensor module that generates a detection signal S according to the state of the measurement site M. As shown in FIG. 1, the detection device 3 is installed, for example, on the facing surface (hereinafter referred to as the detection surface) 16 of the housing part 1 facing the measurement site M. The detection surface 16 is the surface that contacts the measurement site M. As shown in FIG. 2, the detection device 3 of the present embodiment includes a light emitting unit part 11, a light receiving unit part 12, a drive circuit 13, and an output circuit 14. Note that one or both of the drive circuit 13 and the output circuit 14 can also be installed as an external circuit of the detection device 3. That is, the drive circuit 13 and the output circuit 14 can be omitted from the detection device 3.

[0013] The light emitting unit part 11 has a light emitting part (first light emitting part) 50, a light emitting part (second light emitting part) 60, and a light emitting part (third light emitting part) 70. The light emitting part 50, the light emitting part 60, and the light emitting part 70 are light sources that emit light of different wavelengths with respect to the measurement site M.

[0014] The light emitting part 50 emits green light (first light) LG having a green wavelength band of 520 nm to 550 nm toward the measurement site M. The green light LG of the present embodiment is, for example, light with a peak wavelength of 520 nm. The light emitting part 60 emits red light (third light) LR having a red wavelength band of 600 nm to 800 nm toward the measurement site M. The red light LR of the present embodiment is, for example, light with a peak wavelength of 660 nm. The light emitting part 70 emits near-infrared light (second light) LI having a near-infrared wavelength band of 800 nm to 1300 nm toward the measurement site M. The near-infrared light LI of the present embodiment is, for example, light with a peak wavelength of 905 nm. [[ID=十六]]

[0015] [[ID=十七]] As the light emitting elements constituting these light emitting parts 50, light emitting part 60, and light emitting part 70, for example, bare chip type or bullet type LEDs (Light Emitting Diodes) are preferably used. Note that the wavelengths of the light emitted by each light emitting part are not limited to the above numerical ranges. Hereinafter, when the light emitting parts 50, light emitting part 60, and light emitting part 70 are not particularly distinguished, these are collectively referred to as each light emitting part 50, 60, 70.

[0016] The drive circuit 13 causes each of the light emitting units 50, 60, 70 to emit light by supplying a drive current. The drive circuit 13 of the present embodiment causes each of the light emitting units 50, 60, 70 to emit light periodically in a time division manner. The light emitted from each of the light emitting units 50, 60, 70 enters the measurement site M and propagates while repeating reflection and scattering inside the measurement site M, and then is emitted toward the housing unit 1 side and reaches the light receiving unit unit 12. That is, the detection device 3 of the present embodiment is a reflection type optical sensor in which the light emitting unit unit 11 and the light receiving unit unit 12 are located on one side with respect to the measurement site M.

[0017] The light receiving unit unit 12 receives the light coming from the measurement site M due to the light emission of the light emitting unit unit 11. The light receiving unit unit 12 of the present embodiment includes a light receiving unit (first light receiving unit) 51 and a light receiving unit (second light receiving unit) 61. The light receiving unit 51 and the light receiving unit 61 generate detection signals according to the intensity of the received light. Hereinafter, when the light receiving unit 51 and the light receiving unit 61 are not particularly distinguished, they are collectively referred to as "light receiving units 51, 61".

[0018] The light receiving unit 51 receives the green light LG emitted from the light emitting unit 并 propagates inside the measurement site M, and generates a detection signal according to the received light intensity. The light receiving unit 61 receives the red light LR emitted from the light emitting unit 60 and propagating inside the measurement site M, or the near infrared light LI emitted from the light emitting unit 70 and propagating inside the measurement site M, and generates a detection signal according to the received light intensity.

[0019] The output circuit 14 includes, for example, an A / D converter that converts the detection signals generated by each of the light receiving units 51, 61 from analog to digital, and an amplifier circuit that amplifies the converted detection signals (both are not shown in the figure), and generates a plurality of detection signals S (S1, S2, S3) corresponding to different wavelengths. 6]

[0020] Detection signal S1 is a signal representing the light reception intensity of the light receiving unit 51 when it receives green light LG emitted from the light-emitting unit 50. Detection signal S2 is a signal representing the light reception intensity of the light receiving unit 61 when it receives red light LR emitted from the light-emitting unit 60, and detection signal S3 is a signal representing the light reception intensity of the light receiving unit 61 when it receives near-infrared light LI emitted from the light-emitting unit 70.

[0021] Generally, the amount of light absorbed by blood differs between vasodilation and vasoconstriction. Therefore, each detection signal S is a pulse wave signal that includes a periodic fluctuation component corresponding to the pulsating component (volume pulse wave) of the artery inside the measurement site M.

[0022] The drive circuit 13 and output circuit 14 are mounted on the wiring board together with the light-emitting unit 11 and light-receiving unit 12 in the form of IC chips. As mentioned above, it is also possible to install the drive circuit 13 and output circuit 14 outside the detection device 3.

[0023] The control device 5 is an arithmetic processing unit such as a CPU (Central Processing Unit) or FPGA (Field-Programmable Gate Array), and controls the entire measuring device 100. The storage device 6 is composed of, for example, a non-volatile semiconductor memory, and stores the program executed by the control device 5 and various data used by the control device 5. It is also possible to adopt a configuration in which the functions of the control device 5 are distributed across multiple integrated circuits, or a configuration in which some or all of the functions of the control device 5 are realized by dedicated electronic circuits. Although Figure 2 shows the control device 5 and the storage device 6 as separate elements, it is also possible to realize the control device 5, which incorporates the storage device 6, using, for example, an ASIC (Application Specific Integrated Circuit).

[0024] In this embodiment, the control device 5 identifies the subject's biological information from a plurality of detection signals S(S1, S2, S3) generated by the detection device 3 by executing a program stored in the storage device 6. Specifically, the control device 5 identifies the subject's pulse wave from the detection signal S1, which represents the light intensity of green light LG received by the light receiving unit 51. For example, the control device 5 can determine the subject's pulse rate based on the detection signal S1. Furthermore, the control device 5 can determine the subject's oxygen saturation by analyzing the detection signal S2, which represents the light intensity of red light LR received by the light receiving unit 61, and the detection signal S3, which represents the light intensity of near-infrared light LI received by the light receiving unit 61.

[0025] As described above, the control device 5 functions as an information analysis unit that identifies biological information from the detection signal S indicating the detection result by the detection device 3. The control device (information analysis unit) 5 displays the biological information identified from the detection signal S on the display device 4. It is also possible to inform the user of the measurement results via voice output. A configuration that warns the user (indicating a possible impairment of physical function) when the pulse rate or oxygen saturation changes to a value outside a predetermined range is also preferable.

[0026] Figure 3 is a plan view of the detection device 3. Figure 4 is a cross-sectional view taken along the line IV-IV in Figure 3. As shown in Figures 3 and 4, the detection device 3 of this embodiment further comprises a case 40, a light-shielding wall 41, and a sealing layer 42, in addition to the light-emitting unit 11 and the light-receiving unit 12. Note that the drive circuit 13 and the output circuit 14 are not shown in Figures 3 and 4.

[0027] The configuration of the detection device 3 will be described below using the XYZ coordinate system. The X-axis corresponds to the axis along the long side (one side) of the case 40, which has a rectangular outer shape; the Y-axis is perpendicular to the X-axis and corresponds to the axis along the short side (the other side) of the case 40; and the Z-axis is perpendicular to the X-axis and Y-axis, respectively, and corresponds to the axis along the normal of the detection surface 16 that contacts the measurement area M.

[0028] As shown in Figures 3 and 4, the case 40 is a component that houses each element (light-emitting unit 11 and light-receiving unit 12) that constitutes the detection device 3. The case 40 has a box shape including a rectangular flat bottom portion 40a and rectangular frame-shaped side plate portions 40b that protrude from the periphery of the bottom portion 40a toward the +Z side. The case 40 is made of, for example, aluminum. The inner circumferential surface 40b1 of the side plate portion 40b is colored black to provide light shielding. This suppresses reflection on the inner circumferential surface 40b1 of the side plate portion 40b.

[0029] The material and manufacturing method of the case 40 are arbitrary. For example, the case 40 can be formed by injection molding of a resin material. A configuration in which the case 40 is formed integrally with the housing 1 is also preferable.

[0030] The light-emitting unit 11 and the light-receiving unit 12 are mounted on a wiring board (not shown) and installed on the bottom surface 40a of the case 40. The light-shielding wall 41 is positioned between the light-emitting unit 11 and the light-receiving unit 12 in the direction along the X axis. The light-shielding wall 41 is a plate-shaped member that protrudes from the bottom surface 40a to the +Z side and extends in the Y axis direction, separating the housing space inside the case 40 into two in the direction along the X axis. In other words, the light-shielding wall 41 is a member that separates the space housing the light-emitting unit 11 and the light-receiving unit 12 in the direction along the X axis. The light-shielding wall 41 is a member that has light-shielding properties to block light emitted from the light-emitting unit 11 from directly entering the light-receiving unit 12.

[0031] In this embodiment, the light-shielding wall 41 is provided between the light-emitting unit 11, which includes the light-emitting section 50 and the light-emitting section 60, and the light-receiving section 51, in the direction along the X-axis. In other words, the light-shielding wall 41 is a member that shields a portion of the green light LG, red light LR, and near-infrared light LI.

[0032] The sealing layer 42 is a light-transmitting resin material filled in the gap between the light-emitting unit 11 and the light-receiving unit 12 housed in the case 40 and the side plate 40b. The sealing layer 42 seals (moldes) the light-emitting unit 11 and the light-receiving unit 12 within the case 40. The surface of the sealing layer 42 functions as the detection surface 16. Alternatively, instead of sealing with the sealing layer 42, a configuration in which the upper surface of the side plate portion 40b of the case 40 is covered with a translucent substrate may be adopted. In this case, the upper surface of the translucent substrate functions as the detection surface 16.

[0033] The light-emitting unit 11 is installed inside the case 40 such that the light-emitting surfaces of each light-emitting part 50, 60, and 70 are parallel to the XY plane. In other words, each light-emitting part 50, 60, and 70 emits light toward the +Z side.

[0034] As shown in Figure 3, the light-emitting units 50, 60, and 70 are arranged in a line along the Y-axis (first direction) with a gap between them. Specifically, light-emitting unit 60 is located on the +Y side of light-emitting unit 50, and light-emitting unit 70 is located on the -Y side of light-emitting unit 50. In other words, light-emitting unit 50 is located between light-emitting units 60 and 70 in the direction along the Y-axis. Alternatively, it can be said that light-emitting unit 50 is located between light-emitting units 60 and 70.

[0035] On the other hand, the light-receiving unit 12 is installed inside the case 40 such that the light-receiving surfaces of each light-receiving section 51, 61 are parallel to the XY plane. In other words, each light-receiving section 51, 61 is configured to receive light incident from the Z direction.

[0036] As shown in Figure 3, the light-receiving units 51 and 61 are spaced apart from each other and arranged in a direction (second direction) along the X-axis that intersects (is perpendicular to) the Y-axis. Specifically, the light-receiving unit 51 is located on the +X side of the light-emitting unit 11, and the light-receiving unit 61 is located on the +X side of the light-receiving unit 51. In other words, the light-receiving unit 61 is located on the opposite side of the light-emitting unit 11, with the light-receiving unit 51 in between.

[0037] Here, let D1 be the distance from the light-emitting unit 50 to the light-receiving unit 51, D2 be the distance from the light-emitting unit 60 to the light-receiving unit 61, and D3 be the distance from the light-emitting unit 70 to the light-receiving unit 61. Distance D1 corresponds to the distance between the centers of the light-emitting unit 50 and the light-receiving unit 51 when viewed from the Z-axis direction. Distance D2 corresponds to the distance between the centers of the light-emitting unit 60 and the light-receiving unit 61 when viewed from the Z-axis direction. Distance D3 corresponds to the distance between the centers of the light-emitting unit 70 and the light-receiving unit 61 when viewed from the Z-axis direction.

[0038] In the detection device 3 of this embodiment, the distance D1 from the light-emitting unit 50 to the light-receiving unit 51 is shorter than the distance D2 from the light-emitting unit 60 to the light-receiving unit 61. Also, the distance D1 from the light-emitting unit 50 to the light-receiving unit 51 is shorter than the distance D3 from the light-emitting unit 70 to the light-receiving unit 61. Note that distances D2 and D3 are equal. Thus, in the detection device 3 of this embodiment, a configuration is adopted in which a light-receiving unit 51 for receiving green light LG is placed at the position closest to the light-emitting unit 50 that emits green light LG.

[0039] As shown in Figure 4, the light-receiving unit 51 includes a light-receiving element (first sensor unit) 510 that receives green light LG, an angle limiting filter (first angle limiting filter) 511 that limits the incident angle of green light LG reaching the light-receiving element 510, and a bandpass filter 515 that selectively transmits green light LG.

[0040] The light-receiving element 510 is composed of, for example, a photodiode (PD). The angle limiting filter 511 is provided on the light-receiving surface 510a of the light-receiving element 510. The angle limiting filter 511 is formed, for example, by embedding a plug 513 made of a light-shielding material such as tungsten in a light-transmitting silicon oxide layer 512.

[0041] The silicon oxide layer 512 forms an optical path that guides light to the light-receiving surface 510a of the photodetector 510. The plug 513 embedded in the silicon oxide layer 512 limits the angle of incidence of light passing through the optical path (silicon oxide layer 512). That is, if the light incident on the silicon oxide layer 512 is tilted more than a predetermined angle with respect to the optical path, the incident light hits the plug 513, some of the light is absorbed by the plug 513, and the rest is reflected. As the light passes through the optical path, the intensity of the reflected light weakens due to repeated reflections, so the light that can ultimately pass through the angle limiting filter 511 is effectively limited to light whose tilt with respect to the optical path is within a predetermined limiting angle.

[0042] The angle limiting filter 511 has the characteristic of transmitting light incident at an angle smaller than a predetermined incident angle, and blocking light incident at an angle larger than a predetermined incident angle. This allows the angle limiting filter 511 to limit the incident angle of light incident on the photodetector 510. Specifically, the angle limiting filter 511 transmits green light LG that propagates within the body and is incident at a predetermined incident angle (hereinafter referred to as the allowable incident angle), while blocking light incident at an angle larger than the allowable incident angle, such as sunlight or other external light that does not enter the body.

[0043] The bandpass filter 515 selectively transmits the wavelength band of green light LG and absorbs and cuts out other wavelength bands, namely red light LR and near-infrared light LI. The bandpass filter 515 is formed, for example, by alternately stacking multiple low refractive index layers such as silicon oxide and high refractive index layers such as titanium oxide on the angle limiting filter 511.

[0044] On the other hand, the light-receiving unit 61 includes a light-receiving element (second sensor unit) 610 that receives red light LR or near-infrared light LI, and an angle-limiting filter (second angle-limiting filter) 611 that limits the incident angle of red light LR or near-infrared light LI reaching the light-receiving element 610. In other words, in the detection device 3 of this embodiment, the light-receiving unit 61 has a different configuration from the light-receiving unit 51 in that it does not include a bandpass filter that selectively transmits red light LR or near-infrared light LI.

[0045] The light-receiving element 610 is composed of, for example, a photodiode. The angle limiting filter 611 is provided on the light-receiving surface 610a of the light-receiving element 610. The angle limiting filter 611 has the same configuration as the angle limiting filter 511 and is capable of limiting the incident angle of red light LR or near-infrared light LI that reaches the light-receiving element 610. For example, the angle limiting filter 611 transmits red light LR or near-infrared light LI that propagates within the body and is incident at an acceptable incident angle, while cutting out light that is incident at an angle greater than the acceptable incident angle, such as sunlight or other ambient light or red light LR or near-infrared light LI that did not pass through the body.

[0046] Figure 5 is a graph showing the transmission spectrum of skin. In Figure 5, the horizontal axis represents the wavelength of light, and the vertical axis represents the transmittance (in %). Figure 5 shows the transmission spectrum as an example when the skin thickness is 0.43 mm.

[0047] As shown in Figure 5, the transmittance when green light (LG) in the wavelength range (e.g., 520 nm) is incident on the skin is about 30%, when red light (LR) in the wavelength range (e.g., 660 nm) is incident on the skin is about 50% to 60%, and when near-infrared light (LI) in the wavelength range (e.g., 905 nm) is incident on the skin is about 60%.

[0048] The graph in Figure 5 shows that the distance that light can propagate within a living organism differs depending on the wavelength of light. In other words, according to the graph in Figure 5, green light (LG) can only propagate over a shorter distance within the living organism compared to red light (LR) or near-infrared light (LI). This can be rephrased as red light (LR) and near-infrared light (LI) being able to propagate over longer distances within the living organism compared to green light (LG). Note that Figure 5 uses the example of a skin thickness of 0.43 mm, but even with different skin thicknesses, red light (LR) and near-infrared light (LI) will similarly propagate over longer distances within the living organism compared to green light (LG).

[0049] The operation of the detection device 3 in this embodiment will be described below. The detection device 3 of this embodiment includes a light-emitting unit 50 that emits green light LG, a light-emitting unit 60 that emits red light LR having a higher wavelength band than the green light LG, a light-emitting unit 70 that emits near-infrared light LI having a higher wavelength band than the green light LG, a light-receiving unit 51 that receives green light LG emitted from the light-emitting unit 50 and emitted from the measurement site M, a light-receiving unit 61 that receives red light LR emitted from the light-emitting unit 60 and emitted from the measurement site M, and a light-receiving unit 61 that receives near-infrared light LI emitted from the light-emitting unit 70 and emitted from the measurement site M. The light-receiving unit 51 includes a bandpass filter 515 that selectively transmits green light LG, and the distance D1 from the light-emitting unit 50 to the light-receiving unit 51 is shorter than the distance D2 from the light-emitting unit 60 to the light-receiving unit 61. In this embodiment, the distance D1 from the light-emitting unit 50 to the light-receiving unit 51 is shorter than the distance D3 from the light-emitting unit 70 to the light-receiving unit 61.

[0050] In other words, in the detection device 3 of this embodiment, the light-receiving unit 51 is positioned closest to the light-emitting unit 50 that emits green light LG. When the light-receiving unit 51 and the light-emitting unit 50 are positioned close together in this way, the green light LG emitted from the light-emitting unit 50 propagates through the living body over a short distance before entering the light-receiving unit 51. As shown in the graph of Figure 5, since green light LG can only propagate over a short distance through the living body as described above, if the distance between the light-emitting unit 50 that emits green light LG and the light-receiving unit 51 that receives green light LG is short, the green light LG emitted from the living body can enter the light-receiving unit 51 with high intensity.

[0051] In this embodiment, since the light-receiving unit 51 is positioned closest to the light-emitting unit 50, the amount of green light LG that propagates within the body and enters the light-receiving unit 51 can be maximized. Therefore, even when the amount of green light LG emitted from the light-emitting unit 50 is suppressed, the detection device 3 can sufficiently detect the green light LG that has propagated within the body using the light-receiving unit 51. Therefore, the detection device 3 of this embodiment can accurately detect the green light LG at the light receiving unit 51 while reducing the power consumption of the light-emitting unit 11 by suppressing the amount of green light LG emitted from the light-emitting unit 50.

[0052] Here, some of the red light LR and near-infrared light LI emitted from the light-emitting unit 60 may pass through the living body and enter the light-receiving unit 51. In this embodiment, the light-receiving unit 51 includes a bandpass filter 515 that selectively transmits green light LG. Therefore, the light-receiving unit 51 can cut out red light LR and near-infrared light LI, which have different wavelength bands than green light LG. Thus, the light-receiving unit 51 can efficiently receive green light LG emitted from the light-emitting unit 50.

[0053] Figure 6 is a diagram illustrating the operation of the detection device 3. As shown in Figure 6, a portion of the green light LG emitted from the light-emitting unit 50 may be reflected by, for example, the surface of a living organism (measurement site M), and thus may directly enter the light-receiving unit 51 without passing through the living organism. In addition, ambient light such as sunlight may directly enter the light-receiving unit 51 through the gap between the living organism and the detection surface 16. Hereinafter, the green light LG that goes towards the light-receiving unit 51 without passing through the living organism will be referred to as the "first stray light component SL1," and the ambient light that goes directly towards the light-receiving unit 51 will be referred to as the "second stray light component SL2."

[0054] The first stray light component SL1 has a green wavelength band, so it passes through the bandpass filter 515 and is incident on the angle limiting filter 511 located below the bandpass filter 515. As described above, the angle limiting filter 511 has the characteristic of transmitting light incident at an angle smaller than the allowable incident angle and cutting off light incident at an angle larger than the allowable incident angle.

[0055] Since the first stray light component SL1 enters the light-receiving unit 51 without passing through the living body, the angle of incidence of the green light LG to the light-receiving unit 51 becomes larger than the allowable angle of incidence of the angle limiting filter 511. In other words, the first stray light component SL1 is cut off by the angle limiting filter 511. As a result, the light-receiving unit 51 can suppress the incidence of the first stray light component SL1 to the light-receiving surface 510a of the light-receiving element 510 by the angle limiting filter 511.

[0056] The second stray light component SL2 is largely cut off by the bandpass filter 515, but the component containing the green wavelength band within the second stray light component SL2 is transmitted through the bandpass filter 515. Here, as described above, the second stray light component SL2 is incident from the gap between the living body and the detection surface 16, so the incident angle of the second stray light component SL2 to the light receiving unit 51 is greater than the allowable incident angle of the angle limiting filter 511. Therefore, a portion of the second stray light component SL2 that has been transmitted through the bandpass filter 515 (the component containing the green wavelength band) is cut off by the angle limiting filter 511. As a result, the light receiving unit 51 can suppress the incidence of the second stray light component SL2 to the light receiving surface 510a of the light receiving element 510 by the angle limiting filter 511.

[0057] Thus, in the detection device 3 of this embodiment, the green light LG emitted from the light-emitting unit 11 and passing through the living body can be efficiently incident onto the light-receiving surface 510a of the light-receiving element 510. Furthermore, in the detection device 3 of this embodiment, it is possible to make it difficult for the first stray light component SL1 and the second stray light component SL2 to be incident on the light-receiving surface 510a of the light-receiving element 510.

[0058] Therefore, the light-receiving unit 51 can obtain a high signal-to-noise ratio by suppressing the incidence of the first stray light component SL1 and the second stray light component SL2, which are noise sources. As a result, the detection device 3 of this embodiment can receive green light LG with high precision in the light-receiving unit 51, and thus the power consumption of the light-emitting unit 11 can be suppressed by reducing the amount of green light LG emitted in the light-emitting unit 50.

[0059] Furthermore, in the detection device 3 of this embodiment, the distance (distance D2 or distance D3) between the light-emitting unit 60 and the light-emitting unit 70 and the light-receiving unit 61 is greater than the distance D1 between the light-emitting unit 50 and the light-receiving unit 51. In other words, the distance that red light LR and near-infrared light LI travel through the body before they reach the light-receiving unit 61 is greater than the distance that green light LG travels through the body before it reaches the light-receiving unit 51.

[0060] As shown in Figure 5, green light LG can only propagate over a shorter distance within the body compared to red light LR or near-infrared light LI. Therefore, if green light LG were to propagate within the body in a way that it could reach the light-receiving unit 61, it would be sufficiently attenuated as it passed through the body. Consequently, green light LG cannot enter the light-receiving unit 61.

[0061] On the other hand, red light (LR) and near-infrared light (LI) can propagate further within the body than green light (LG). Therefore, even when red light (LR) and near-infrared light (LI) propagate over longer distances within the body than green light (LG), they can still be incident on the light-receiving unit (61), which is further away from the light-emitting unit (11), with sufficient light intensity.

[0062] In this embodiment, since only red light LR and near-infrared light LI are incident on the light-receiving unit 61, there is no need to provide the light-receiving unit 61 with a bandpass filter that selectively transmits red light LR and near-infrared light LI and cuts out green light LG. In other words, in the detection device 3 of this embodiment, it is possible to adopt the above configuration in which only the light-receiving unit 51 includes the bandpass filter 515 and the light-receiving unit 61 does not include a bandpass filter. Therefore, the detection device 3 of this embodiment can reduce costs by omitting the bandpass filter in the light-receiving unit 61.

[0063] Furthermore, some of the red light LR emitted from the light-emitting unit 60, or some of the near-infrared light LI emitted from the light-emitting unit 70, may directly enter the light-receiving unit 61 without passing through the living body. Also, ambient light such as sunlight may directly enter the light-receiving unit 61 through the gap between the living body and the detection surface 16. Hereinafter, the red light LR or near-infrared light LI that directly enters the light-receiving unit 61 without passing through the living body will be collectively referred to as "third stray light component SL3," and ambient light that directly enters the light-receiving unit 61 will be referred to as "fourth stray light component SL4."

[0064] Since the third stray light component SL3 enters the angle limiting filter 611 without passing through the living body, the angle of incidence of the third stray light component SL3 to the light receiving unit 61 is greater than the allowable angle of incidence of the angle limiting filter 611. Also, since the fourth stray light component SL4 enters through the gap between the living body and the detection surface 16, the angle of incidence of the fourth stray light component SL4 to the light receiving unit 61 is greater than the allowable angle of incidence of the angle limiting filter 611.

[0065] Therefore, the third stray light component SL3 and the fourth stray light component SL4 are effectively cut off by the angle limiting filter 611. As a result, the light receiving unit 61 can suppress the incidence of the third stray light component SL3 and the fourth stray light component SL4 onto the light receiving surface 610a of the light receiving element 610 by the angle limiting filter 611.

[0066] Thus, in the detection device 3 of this embodiment, the red light LR or near-infrared light LI emitted from the light-emitting unit 11 and passing through the living body can be efficiently incident onto the light-receiving surface 610a of the light-receiving element 610. Furthermore, in the detection device 3 of this embodiment, it is possible to make it difficult for the third stray light component SL3 and the fourth stray light component SL4 to be incident onto the light-receiving surface 610a of the light-receiving element 610.

[0067] Therefore, the light-receiving unit 61 can obtain a high signal-to-noise ratio by suppressing the incidence of the third stray light component SL3 and the fourth stray light component SL4, which are noise sources. According to the detection device 3 of this embodiment, since the red light LR and near-infrared light LI are efficiently received by the light-receiving unit 61, the amount of light emitted by the light-emitting unit 60 and the light-emitting unit 70 can be reduced, thereby reducing the power consumption of the light-emitting unit 11.

[0068] As described above, with the detection device 3 of this embodiment, even when the amount of light emitted from the light-emitting units 50, 60, and 70 is reduced to lower the power consumption of the light-emitting unit 11, the light-receiving unit 12 can receive light that has passed through the living body with high precision. Furthermore, in the detection device 3 of this embodiment, costs can be reduced by omitting the bandpass filter in the light-receiving unit 61.

[0069] Furthermore, in the detection device 3 of this embodiment, as a measure against stray light, it is not necessary to provide a light-shielding member between the light-receiving unit 51 and the light-receiving unit 61 as in the conventional method. Therefore, the space required for providing a light-shielding member is eliminated, which suppresses the enlargement of the detection device 3 and consequently allows for a smaller overall device configuration.

[0070] (Second Embodiment) Next, a detection device of the second embodiment will be described. In the first embodiment, an example was given in which the light receiving unit 61 receives both red light LR and near-infrared light LI. However, the detection device of this embodiment differs from the first embodiment in that it is provided with light receiving units that receive red light LR and near-infrared light LI individually.

[0071] Figure 7 is a plan view of the detection device of this embodiment. Figure 8 is a cross-sectional view taken along the line VIII-VIII in Figure 7. Components and parts common to the first embodiment are denoted by the same reference numerals, and their details are omitted from the description. As shown in Figures 7 and 8, the light receiving unit 112 in the detection device 3A of this embodiment includes a light receiving unit (first light receiving unit) 151, a light receiving unit (second light receiving unit) 161, and a light receiving unit (third light receiving unit) 171.

[0072] The light-receiving unit 151 receives the green light LG emitted from the light-emitting unit 50 and propagating inside the measurement area M, and generates a detection signal according to the received light intensity. The light-receiving unit 161 receives near-infrared light LI emitted from the light-emitting unit 70 and propagating inside the measurement area M, and generates a detection signal according to the received light intensity. The light-receiving unit 171 receives the red light LR emitted from the light-emitting unit 60 and propagating inside the measurement area M, and generates a detection signal according to the received light intensity. In other words, in this embodiment, the light-emitting unit 50 corresponds to the "first light-emitting unit," and the green light LG emitted from the light-emitting unit 50 corresponds to the "first light." The light-emitting unit 70 corresponds to the "second light-emitting unit," and the near-infrared light LI emitted from the light-emitting unit 70 corresponds to the "second light." The light-emitting unit 60 corresponds to the "third light-emitting unit," and the red light LR emitted from the light-emitting unit 60 corresponds to the "third light."

[0073] The detection device 3A of this embodiment differs from the detection device 3 of the above embodiment in that it receives red light LR and near-infrared light LI individually with two light receiving units (light receiving unit 171 and light receiving unit 161).

[0074] The light-receiving unit 112 is installed inside the case 40 such that the light-receiving surfaces of each light-receiving section 151, 171, and 161 are parallel to the XY plane. Specifically, the light-receiving section 151 is located on the +X side of the light-emitting unit 11, the light-receiving section 171 is located on the +X side of the light-receiving section 151, and the light-receiving section 161 is located on the +X side of the light-receiving section 171. In other words, the light-receiving section 171 is located between the light-receiving sections 151 and 161.

[0075] In this embodiment, the distance from the light-emitting unit 50 to the light-receiving unit 151 is defined as D4. Distance D4 corresponds to the distance between the centers of the light-emitting unit 50 and the light-receiving unit 151 when viewed from a plan view in the Z-axis direction. Furthermore, the distance from the light-emitting unit 70 to the light-receiving unit 161 is defined as D5. Distance D5 corresponds to the distance between the centers of the light-emitting unit 70 and the light-receiving unit 161 when viewed from a planar perspective along the Z-axis. Furthermore, the distance from the light-emitting unit 60 to the light-receiving unit 171 is defined as D6. Distance D6 corresponds to the distance between the centers of the light-emitting unit 60 and the light-receiving unit 171 when viewed from a planar perspective along the Z-axis.

[0076] In the detection device 3A of this embodiment, the distance D4 from the light-emitting unit 50 to the light-receiving unit 151 is shorter than the distance D5 from the light-emitting unit 70 to the light-receiving unit 161. Also, the distance D4 from the light-emitting unit 50 to the light-receiving unit 151 is shorter than the distance D6 from the light-emitting unit 60 to the light-receiving unit 171. Note that distance D6 is shorter than distance D5.

[0077] In the detection device 3A of this embodiment, as in the above embodiment, a configuration is adopted in which a light receiving unit 151 for receiving green light LG is placed at the position closest to the light-emitting unit 50 that emits green light LG.

[0078] The light-receiving unit 151 has the same configuration as the light-receiving unit 51 in the above embodiment. That is, the light-receiving unit 151 includes a light-receiving element 510 that receives green light LG, an angle limiting filter 511, and a bandpass filter 515.

[0079] In the detection device 3A of this embodiment, the light-receiving unit 161 that receives near-infrared light LI is configured to be located at the position furthest from the light-emitting unit 11. The light-receiving unit 161 has the same configuration as the light-receiving unit 61 of the above embodiment. The light-receiving unit 161 includes a light-receiving element (second sensor unit) 1610 that receives near-infrared light LI, and an angle limiting filter (second angle limiting filter) 1611 that limits the incident angle of the near-infrared light LI reaching the light-receiving element 1610.

[0080] Green light LG can only propagate over a shorter distance within the body compared to red light LR or near-infrared light LI. Therefore, green light LG does not reach the light-receiving unit 161. Also, as shown in Figure 5, red light LR can propagate over a shorter distance within the body compared to near-infrared light LI. Therefore, red light LR is sufficiently attenuated within the body before reaching the light-receiving unit 161, so the amount of red light LR incident on the light-receiving unit 161 is small. Accordingly, with the detection device 3A of this embodiment, the bandpass filter that selectively transmits near-infrared light LI can be omitted in the light-receiving unit 161. Thus, the detection device 3A of this embodiment can reduce costs by omitting the bandpass filter in the light-receiving unit 161.

[0081] The light-receiving unit 171 has the same configuration as the light-receiving unit 151. That is, the light-receiving unit 171 includes a light-receiving element 1710 that receives red light LR, an angle limiting filter 1711 that limits the incident angle of red light LR reaching the light-receiving element 1710, and a bandpass filter 1715 that selectively transmits red light LR. The bandpass filter 1715 has the characteristic of selectively transmitting the wavelength band of red light LR and absorbing and cutting out green light LG and near-infrared light LI.

[0082] In the detection device 3A of this embodiment, the distance (distance D6) between the light-emitting unit 60 that emits red light LR and the light-receiving unit 171 that receives the red light LR is shorter than the distance (distance D5) between the light-emitting unit 70 that emits near-infrared light LI and the light-receiving unit 161 that receives the near-infrared light LI. Therefore, green light LG that has propagated within the body may be incident on the light-receiving unit 171 without being sufficiently attenuated. Furthermore, since near-infrared light LI can propagate over longer distances within the body than green light LG, there is a risk that it may enter the light-receiving unit 171 with a stronger intensity than green light LG. In contrast, in this embodiment, the light-receiving unit 171 is equipped with a bandpass filter 1715, which allows red light LR to be efficiently incident onto the light-receiving element 1710.

[0083] According to the detection device 3A of this embodiment, it is possible to make it difficult for stray light components to enter the light-receiving unit 151, and to efficiently direct the green light LG emitted from the light-emitting unit 11 and passed through the living body into the light-receiving unit 151.

[0084] Furthermore, according to the detection device 3A of this embodiment, it is possible to make it difficult for stray light components to be incident on the light-receiving unit 171, and to efficiently incident the red light LR emitted from the light-emitting unit 11 and passing through the living body onto the light-receiving unit 171. Also, it is possible to make it difficult for stray light components to be incident on the light-receiving unit 161, and to efficiently incident the near-infrared light LI emitted from the light-emitting unit 11 and passing through the living body onto the light-receiving unit 161.

[0085] As described above, with the detection device 3A of this embodiment, light can be efficiently received in each light receiving unit 151, 161, and 171, so the amount of light emitted by the light emitting units 50, 60, and 70 can be reduced, and the power consumption of the light emitting unit 11 can be reduced. Furthermore, with the detection device 3A of this embodiment, a light shielding member for stray light countermeasures is not required, so the device configuration can be made smaller.

[0086] Although the present invention has been described above based on the embodiments described above, the present invention is not limited to the embodiments described above and can be implemented in various embodiments without departing from the spirit of the invention. For example, although the above embodiment uses humans as an example of a living organism, the present invention is also applicable to measuring the biological information of other animals (e.g., pulse rate).

[0087] Furthermore, although the above embodiment of the measuring device 100 was given as an example in which the detection device 3 is provided inside the housing 1, the installation location of the detection device 3 is not limited to this, and for example, it may be embedded in the belt 2. Furthermore, although a wristwatch-type configuration was given as an example of the measuring device 100 in the above embodiment, the present invention can also be applied to configurations such as a necklace type worn around the subject's neck, a sticker type attached to the subject's body, or a head-mounted display type worn on the subject's head.

[0088] Furthermore, in the detection device 3 of the first embodiment described above, the example given was that each of the light-emitting units 50, 60, and 70 is emitted in a time-division manner. However, since each light-receiving unit 61 corresponding to the green light LG of the light-emitting unit 50 is individually provided, the light-emitting unit 50 may be kept lit continuously instead of in a time-division manner.

[0089] A detection device according to one embodiment of the present invention may have the following configuration. A detection device according to one aspect of the present invention includes a first light-emitting unit that emits first light having a green wavelength band, a second light-emitting unit that emits second light having a wavelength band higher than the green wavelength band, a first light-receiving unit that receives first light emitted from the first light-emitting unit and emitted from a living organism, and a second light-receiving unit that receives second light emitted from the second light-emitting unit and emitted from a living organism, wherein the first light-receiving unit includes a bandpass filter that selectively transmits the first light, and the distance from the first light-emitting unit to the first light-receiving unit is shorter than the distance from the second light-emitting unit to the second light-receiving unit.

[0090] Another embodiment of the present invention provides a detection device comprising: a first light-emitting unit that emits first light having a green wavelength band; a second light-emitting unit that emits second light having a wavelength band higher than the green wavelength band; a first light-receiving unit that receives first light emitted from the first light-emitting unit and emitted from a living organism; and a second light-receiving unit that receives second light emitted from the second light-emitting unit and emitted from a living organism, wherein the distance from the first light-emitting unit to the first light-receiving unit is shorter than the distance from the second light-emitting unit to the second light-receiving unit; the first light-receiving unit includes a bandpass filter that selectively transmits the first light; and the second light-receiving unit does not include a bandpass filter that selectively transmits the second light.

[0091] In one embodiment of the present invention, the detection device may include a first light receiving unit that includes a first sensor unit that receives first light and a first angle limiting filter that limits the incident angle of the first light reaching the first sensor unit, and the second light receiving unit that includes a second sensor unit that receives second light and a second angle limiting filter that limits the incident angle of the second light reaching the second sensor unit.

[0092] In one embodiment of the present invention, the first light-emitting unit and the second light-emitting unit may be arranged side by side in a first direction, and the first light-receiving unit and the second light-receiving unit may be arranged side by side in a second direction intersecting the first direction.

[0093] In one embodiment of the present invention, the detection device further comprises a third light-emitting unit that emits a third light, wherein the second light-emitting unit emits light in one of the wavelength bands of the red wavelength band or the near-infrared wavelength band as the second light, the third light-emitting unit emits light in the other wavelength band of the red wavelength band or the near-infrared wavelength band as the third light, and the second light-receiving unit receives the third light emitted from the third light-emitting unit and emitted from the living body, and the distance from the first light-emitting unit to the first light-receiving unit may be shorter than the distance from the third light-emitting unit to the second light-receiving unit.

[0094] In one embodiment of the present invention, the detection device further comprises a third light-emitting unit that emits a third light, and a third light-receiving unit that receives the third light emitted from the third light-emitting unit and emitted from a living organism, wherein the second light-emitting unit emits light in one of the wavelength bands of the red wavelength band or the near-infrared wavelength band as the second light, and the third light-emitting unit emits light in the other wavelength band of the red wavelength band or the near-infrared wavelength band as the third light, and the distance from the first light-emitting unit to the first light-receiving unit may be shorter than the distance from the third light-emitting unit to the third light-receiving unit.

[0095] In one embodiment of the present invention, the first light-emitting unit may be configured to be positioned between the second light-emitting unit and the third light-emitting unit in a first direction.

[0096] In one embodiment of the present invention, the detection device may further include a light-shielding wall provided between the first light-emitting unit and the second light-emitting unit and the first light-receiving unit, which blocks a portion of the first light and the second light.

[0097] A measuring device according to one embodiment of the present invention may have the following configuration. A measuring device according to one aspect of the present invention comprises a detection device according to the above-described aspect and an information analysis unit that identifies biological information from a detection signal indicating the detection result by the detection device. [Explanation of Symbols]

[0098] 3,3A...Detection device, 5...Control device (information analysis unit), 51,151...Light receiving unit (first light receiving unit), 61,161...Light receiving unit (second light receiving unit), 41...Light shielding wall, 50...Light emitting unit (first light emitting unit), 60...Light emitting unit (second light emitting unit), 70...Light emitting unit (third light emitting unit), 100...Measurement device, 171...Light receiving unit (third light receiving unit), 510...Light receiving element (first sensor unit), 511...Angle control Limit filter (first angle limit filter), 515...bandpass filter, 610, 1610...photodetector (second sensor unit), 611, 1611...angle limit filter (second angle limit filter), D1, D2, D3, D4, D5, D6...distance, LG...green light (first light), LI...near-infrared light (second light), LR...red light (third light), M...measurement site (living organism).

Claims

1. A first light-emitting unit that emits first light having a green wavelength band toward a living organism, A second light-emitting unit is provided so as to be aligned with the first light-emitting unit in a first direction and emits second light having a wavelength band higher than the green wavelength band toward the living organism, A first light receiving unit that receives the first light emitted from the first light-emitting unit and propagated within the living body, A second light-receiving unit is provided so as to be adjacent to the first light-receiving unit in a second direction intersecting the first direction, and receives the second light emitted from the second light-emitting unit and propagating within the living body, A case portion having a bottom surface portion including a first region for housing the first light-emitting portion and the second light-emitting portion, and a second region for housing the first light-receiving portion and the second light-receiving portion, A first sealing member is filled into the first region and seals the first light-emitting portion and the second light-emitting portion, The second region is filled with a second sealing member that seals the first light-receiving portion and the second light-receiving portion, The case portion has a light-shielding wall provided between the first sealing member and the second sealing member in the second direction, The light-shielding wall protrudes from the bottom surface along a third direction perpendicular to the first and second directions, so as to separate the first sealing member and the second sealing member. The light-shielding wall extends along the first direction and has thickness in the second direction, The surface of the second sealing member is a plane perpendicular to the axis along the third direction, The first light receiving unit includes a bandpass filter that selectively transmits the first light from the first light and second light incident on the surface of the second sealing member, a first angle limiting filter that selectively transmits the first light that is incident at an angle smaller than a predetermined incident angle from the first light that has passed through the bandpass filter, and a first sensor that receives the first light that has passed through the first angle limiting filter. The first angle limiting filter is provided between the first sensor and the bandpass filter in the third direction. The second light receiving unit includes a second angle limiting filter that selectively transmits the second light incident at an angle smaller than a predetermined incident angle from the second light incident from the surface of the second sealing member, and a second sensor that receives the second light that has passed through the second angle limiting filter. The second light receiving unit does not include a bandpass filter that selectively transmits the second light. The distance from the first light-emitting unit to the first light-receiving unit is shorter than the distance from the second light-emitting unit to the second light-receiving unit. In the second region of the case portion, there is no light-shielding wall between the first light-receiving portion and the second light-receiving portion in the second direction. Detection device.

2. The case portion is further housed in the first region and comprises a third light-emitting portion that emits a third light, The second light-emitting unit emits light in either the red wavelength band or the near-infrared wavelength band as the second light. The third light-emitting unit emits light in the other wavelength band of the red wavelength band or the near-infrared wavelength band as the third light. The second light-receiving unit receives the third light emitted from the third light-emitting unit and emitted from the living organism, and the second light, The distance from the first light-emitting unit to the first light-receiving unit is shorter than the distance from the third light-emitting unit to the second light-receiving unit. The detection device according to claim 1.

3. A third light-emitting unit is housed in the first region of the case portion and emits a third light, The device further comprises a third light-receiving unit that receives the third light emitted from the third light-emitting unit and emitted from the living organism, The second light-emitting unit emits light in either the red wavelength band or the near-infrared wavelength band as the second light. The third light-emitting unit emits light in the other wavelength band of the red wavelength band or the near-infrared wavelength band as the third light. The distance from the first light-emitting unit to the first light-receiving unit is shorter than the distance from the third light-emitting unit to the third light-receiving unit. The third light-receiving unit is housed in the second region of the case portion. In the second region of the case portion, there is no light-shielding wall between the second light-receiving portion and the third light-receiving portion in the second direction. The detection device according to claim 1.

4. The first light-emitting unit is positioned between the second light-emitting unit and the third light-emitting unit in the first direction. The detection device according to claim 2 or claim 3.

5. A detection device according to any one of claims 1 to 4, The system includes an information analysis unit that identifies biological information from a detection signal indicating the detection result by the aforementioned detection device. Measuring device.

Images