Detection device and measurement device

Abstract

To provide a detecting device and a measuring device with improved detection accuracy.SOLUTION: A detecting device includes a light emitting part for emitting light and a light receiving part having an angle restriction member for restricting an incident angle of the light from the light emitting part. The light receiving part includes a first light receiving region and a second light receiving region more away from the light emitting part than the first light receiving region. The angle restriction member includes a first restriction region corresponding to the first light receiving region and a second restriction region corresponding to the second light receiving region. An extent of angle restriction in the second restriction region is smaller than that in the first restriction region.SELECTED DRAWING: Figure 7

Description

Technical Field

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

Background Art

[0002] Various measurement techniques for non-invasively measuring biological information such as pulse waves have been conventionally proposed. 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 is incident by being reflected by the living body, a technique is disclosed in which a stray light that passes through a spectroscopic filter is cut by an angle limiting filter by providing a spectroscopic filter and an angle limiting filter 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 there is variation in the amount of received light within the plane of the light receiving unit, it has been desired to provide a new technique that can further improve the detection accuracy by efficiently making light incident on the light receiving unit.

Means for Solving the Problems

[0005] According to one aspect of the present invention, there is provided a light emitting unit that emits light, and a light receiving unit having an angle limiting member that limits the incident angle of light from the light emitting unit, the light receiving unit including a first light receiving region and a second light receiving region that is separated from the light emitting unit more than the first light receiving region, the angle limiting member including a first limiting region corresponding to the first light receiving region and a second limiting region corresponding to the second light receiving region, and the degree of angle limitation in the second limiting region is When small and taking the direction in which the light emitting part and the light receiving part are arranged as the first direction, the angle limiting member has a plurality of light shielding walls provided in the light receiving part, and the interval between adjacent walls in the first direction in the second limiting region among the plurality of light shielding walls is larger than the interval between adjacent walls in the first direction in the first limiting region among the plurality of light shielding walls. The light emitting part includes a first light emitting element that emits first light having a green wavelength band, and a second light emitting element that is provided in a second direction intersecting the first direction with respect to the first light emitting element and emits second light having a wavelength band longer than the green wavelength band. The light receiving part includes a first light receiving element that receives the first light from the first light emitting element, and a second light receiving element that receives the second light from the second light emitting element. In the first direction, the first light receiving element is provided closer to the light emitting part than the second light receiving element. The angle limiting member includes a first angle limiting filter that limits the incident angle of the first light with respect to the first light receiving element, and a second angle limiting filter that limits the incident angle of the second light with respect to the second light receiving element. The degree of angle limitation of the first limiting region in the second angle limiting filter is smaller than the degree of angle limitation of the first limiting region in the first angle limiting filter. A detection device is provided.

[0006] According to one aspect of the present invention, there is provided a detection device including a light emitting unit that emits light to a living body, a light receiving unit that is arranged in a first direction with respect to the light emitting unit and receives light from the living body, and a plurality of light shielding walls that are arranged in the first direction and limit an incident angle of light to the light receiving unit, wherein a distance between the light shielding walls in a region far from the light emitting unit is larger than a distance between the light shielding walls in a region close to the light emitting unit.

[0007] According to one aspect of the present invention, there is provided a measuring device including the detection device according to the above aspect and an information analysis unit that specifies biological information from a detection signal indicating a detection result obtained by the detection device.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Modes for Carrying Out the Invention

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following figures, for the purpose of making each member recognizable, the scales and angles of each member are made different from the actual ones.

[0010] (First Embodiment) FIG. 1 is a side view of the measuring device 100 according to the first embodiment. The measuring device 100 of the present embodiment shown in FIG. 1 is a biological measurement device that non-invasively measures biological information of a subject (for example, a human) as an example of a living body, and is attached to a part (hereinafter referred to as "measurement part") M to be measured of the subject's body. The measuring device 100 of the present embodiment is a wristwatch-type portable device including a main body part 1 and a belt 2, and can be attached to the subject's wrist by winding the belt-shaped belt 2 around the wrist as an example of the measurement part (living body) M. In the present embodiment, the pulse wave (for example, heart rate) and oxygen saturation (SpO2) of the subject are exemplified as biological information. The pulse wave means the time change of the volume in the blood vessel linked to the heartbeat of the heart. The oxygen saturation means the ratio (%) of hemoglobin combined with oxygen in the hemoglobin in the subject's blood, and is an index for evaluating the subject's respiratory function.

[0011] FIG. 2 is a configuration diagram focusing on the functions of the measuring device 100. As shown in FIG. 2, the measuring device 100 of the present 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 main body part 1. As shown in FIG. 1, the display device 4 is installed on the surface of the main body part 1 opposite to the measurement part M, and displays various images including the 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 opposing surface (hereinafter referred to as the detection surface) 16 of the main body 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 (light emitting part) 11, a light receiving unit (light receiving part) 12, a drive circuit 13, and an output circuit 14. It is also possible to install one or both of the drive circuit 13 and the output circuit 14 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 11 has a first light emitting element 50, a second light emitting element 60, and a third light emitting element 70. The first light emitting element 50, the second light emitting element 60, and the third light emitting element 70 are elements that emit light of different wavelengths with respect to the measurement site M.

[0014] The first light emitting element 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 second light emitting element 60 emits red light (second 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 third light emitting element 70 emits near-infrared light (third 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.

[0015] As the light-emitting elements constituting these first light-emitting element 50, second light-emitting element 60, and third light-emitting element 70, for example, bare chip type or bullet type LEDs (Light Emitting Diodes) are preferably used. Note that the wavelength of the light emitted from each light-emitting unit is not limited to the above numerical range. Hereinafter, when the first light-emitting element 50, second light-emitting element 60, and third light-emitting element 70 are not particularly distinguished, they are collectively referred to as "each light-emitting element 50, 60, 70".

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

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

[0018] The first light-receiving element 51 receives the green light LG emitted from the first light-emitting element 50 and propagating inside the measurement site M, and generates a detection signal according to the received intensity. The second light-receiving element 61 receives the red light LR emitted from the second light-emitting element 60 and propagating inside the measurement site M, or the near-infrared light LI emitted from the third light-emitting element 70 and propagating inside the measurement site M, and generates a detection signal according to the received intensity.

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

[0020] The detection signal S1 is a signal representing the light receiving intensity of the first light receiving element 51 when receiving the green light LG emitted from the first light emitting element 50. The detection signal S2 is a signal representing the light receiving intensity of the second light receiving element 61 when receiving the red light LR emitted from the second light emitting element 60, and the detection signal S3 is a signal representing the light receiving intensity of the second light receiving element 61 when receiving the near-infrared light LI emitted from the third light emitting element 70.

[0021] Generally, since the amount of light absorption by blood differs between when blood vessels are dilated and when they are constricted, each detection signal S becomes a pulse wave signal including a periodic fluctuation component corresponding to the pulsation component (volume pulse wave) of the artery inside the measurement site M.

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

[0023] The control device 5 is an arithmetic processing device such as a CPU (Central Processing Unit) or an 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 programs executed by the control device 5 and various data used by the control device 5. Note that a configuration in which the functions of the control device 5 are distributed among a plurality of integrated circuits, or a configuration in which some or all of the functions of the control device 5 are realized by dedicated electronic circuits may also be adopted. In FIG. 2, the control device 5 and the storage device 6 are illustrated as separate elements, but it is also possible to realize a control device 5 including the storage device 6 by, for example, an ASIC (Application Specific Integrated Circuit) or the like.

[0024] By executing the program stored in the storage device 6, the control device 5 of the present embodiment identifies the biological information of the subject from the plurality of detection signals S (S1, S2, S3) generated by the detection device 3. Specifically, the control device 5 can identify the pulse interval (PPI) of the subject from the detection signal S1 representing the received light intensity of the green light LG by the first light receiving element 51. Further, the control device 5 can identify the oxygen saturation (SpO2) of the subject by analyzing the detection signal S2 representing the received light intensity of the red light LR by the second light receiving element 61 and the detection signal S3 representing the received light intensity of the near-infrared light LI by the second light receiving element 61.

[0025] As described above, in the measuring device 100 of the present embodiment, 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 causes the display device 4 to display the biological information identified from the detection signal S. Note that it is also possible to notify the user of the measurement result by voice output. A configuration for notifying the user of a warning (possibility of a physical function disorder) when the pulse rate or oxygen saturation fluctuates to a value outside a predetermined range is also preferable.

[0026] FIG. 3 is a plan view of the detection device 3 of the present embodiment. FIG. 4 is a cross-sectional view taken along the line IV-IV in FIG. 3. As shown in FIGS. 3 and 4, the detection device 3 of the present embodiment further includes a case 40 and a sealing layer 42 in addition to the light emitting unit section 11 and the light receiving unit section 12. In FIGS. 3 and 4, the drive circuit 13 and the output circuit 14 are not shown.

[0027] Hereinafter, the configuration of the detection device 3 will be described using the XYZ coordinate system. The X axis corresponds to an axis along the long side (one side) of the case 40 having a rectangular outer shape, the Y axis is orthogonal to the X axis and corresponds to an axis along the short side (the other side) of the case 40, and the Z axis is orthogonal to the X axis and the Y axis respectively and corresponds to an axis along the thickness direction of the case 40.

[0028] As shown in FIGS. 3 and 4, the case 40 is a member that holds each element (the light emitting unit section 11 and the light receiving unit section 12) constituting the detection device 3. The case 40 has a box shape including a rectangular flat bottom surface portion 40a, a rectangular frame-shaped frame plate portion 40b protruding from the periphery of the bottom surface portion 40a to the +Z side, and a partition wall 41. The case 40 is formed of, for example, aluminum. The inner peripheral surface 40b1 of the frame plate portion 40b has light-shielding properties by being colored black. Thereby, reflection on the inner peripheral surface 40b1 of the frame plate portion 40b is suppressed.

[0029] Note that the material and manufacturing method of the case 40 are arbitrary. For example, it is also possible to form the case 40 by injection molding of a resin material. Also, a configuration in which the case 40 is formed integrally with the main body portion 1 is also suitable.

[0030] The light emitting unit section 11 and the light receiving unit section 12 are installed on the bottom surface portion 40a of the case 40 in a state of being mounted on a wiring board (not shown). Inside the case 40, the light emitting unit section 11 and the light receiving unit section 12 are arranged in the X-axis direction (the first direction).

[0031] The partition wall 41 is a plate-shaped member that protrudes from the bottom surface portion 40a toward the +Z side and extends in the Y-axis direction, and separates the accommodation space in the case 40 into two in the X-axis direction. That is, the partition wall 41 is a member that separates the space for accommodating the light-emitting unit portion 11 and the light-receiving unit portion 12 in the direction along the X-axis. The partition wall 41 is a member having a light-shielding property for shielding the light emitted from the light-emitting unit portion 11 from directly entering the light-receiving unit portion 12. It can also be said that the partition wall 41 is a member that shields a part of the green light LG, the red light LR, and the near-infrared light LI.

[0032] The sealing layer 42 is a light-transmissive resin material filled in the gaps between the light-emitting unit portion 11 and the light-receiving unit portion 12 accommodated in the case 40 and the frame plate portion 40b. In the present embodiment, the sealing layer 42 seals each of the light-emitting elements 50, 60, 70 and each of the light-receiving elements 51, 61. The sealing layer 42 seals (molds) the light-emitting unit portion 11 and the light-receiving unit portion 12 in the case 40. In the present embodiment, the upper surface of the sealing layer 42 is flush with the upper surfaces of the frame plate portions 40b and 41 of the case 40. The surface of the sealing layer 42 functions as the detection surface 16.

[0033] The light-emitting unit portion 11 is installed in the case 40 such that the light-emitting surfaces of the respective light-emitting elements 50, 60, 70 are parallel to the XY plane. That is, each of the light-emitting elements 50, 60, 70 is adapted to emit light toward the +Z side. The light-receiving unit portion 12 is installed in the case 40 such that the light-receiving surfaces of the respective light-receiving elements 51, 61 are parallel to the XY plane. That is, each of the light-receiving elements 51, 61 is adapted to receive light incident from the Z direction.

[0034] As shown in FIG. 3, the light emitting elements 50, 60, 70 are arranged side by side in the Y-axis direction (second direction) orthogonal (intersecting) to the X-axis direction with a space therebetween. Specifically, the second light emitting element 60 is arranged on the +Y side of the first light emitting element 50, and the third light emitting element 70 is arranged on the -Y side of the first light emitting element 50. That is, the first light emitting element 50 is arranged between the second light emitting element 60 and the third light emitting element 70 in the direction along the Y-axis. In other words, it can also be said that the first light emitting element 50 is located between the second light emitting element 60 and the third light emitting element 70.

[0035] The light receiving elements 51, 61 are arranged side by side in the X-axis direction intersecting (orthogonal to) the Y-axis with a space therebetween. Specifically, the first light receiving element 51 is arranged on the +X side of the light emitting unit 11, and the second light receiving element 61 is arranged on the +X side of the first light receiving element 51. That is, the second light receiving element 61 is arranged on the side opposite to the light emitting unit 11 with respect to the first light receiving element 51.

[0036] Here, let the distance from the first light emitting element 50 to the first light receiving element 51 be D1, the distance from the second light emitting element 60 to the second light receiving element 61 be D2, and the distance from the third light emitting element 70 to the second light receiving element 61 be D3. The distance D1 corresponds to the distance between the respective central portions when the first light emitting element 50 and the first light receiving element 51 are viewed in plan from the Z-axis direction. The distance D2 corresponds to the distance between the respective central portions when the second light emitting element 60 and the second light receiving element 61 are viewed in plan from the Z-axis direction. The distance D3 corresponds to the distance between the respective central portions when the third light emitting element 70 and the second light receiving element 61 are viewed in plan from the Z-axis direction.

[0037] In the detection device 3 of the present embodiment, the distance D1 from the first light emitting element 50 to the first light receiving element 51 is shorter than the distance D2 from the second light emitting element 60 to the second light receiving element 61. The distance D1 from the first light emitting element 50 to the first light receiving element 51 is shorter than the distance D3 from the third light emitting element 70 to the second light receiving element 61. The distance D2 and the distance D3 are equal. Thus, in the detection device 3 of this embodiment, a configuration is adopted in which the first light receiving element 51 for receiving the green light LG is arranged at the position closest to the first light emitting element 50 that emits the green light LG. That is, the first light receiving element 51 is provided closer to the light emitting unit 11 than the second light receiving element 61 in the X-axis direction in which the light emitting unit 11 and the light receiving unit 12 are arranged.

[0038] As shown in FIG. 4, the first light receiving element 51 includes a sensor 20, a first angle limiting filter (angle limiting member) 21, and a band-pass filter 22.

[0039] The sensor 20 is composed of, for example, a photo diode (PD: Photo Diode). The first angle limiting filter 21 is provided so as to cover the entire light receiving surface 20a of the sensor 20.

[0040] The first angle limiting filter 21 has a characteristic of transmitting light incident at an angle smaller than a predetermined incident angle and cutting off light incident at an angle larger than the predetermined incident angle without transmitting it. Thereby, the first angle limiting filter 21 can limit the incident angle of the light incident on the sensor 20. Specifically, the first angle limiting filter 21 transmits light incident at a predetermined incident angle (hereinafter referred to as the allowable incident angle) by propagating through the living body and guides it to the sensor 20, and cuts off light incident at an angle larger than the allowable incident angle, such as external light such as sunlight or light that did not enter the living body, so that it does not enter the sensor 20. That is, the first angle limiting filter 21 is an angle limiting member that limits the incident angle of the green light LG from the first light emitting element 50 with respect to the sensor 20. The details of the configuration of the first angle limiting filter 21 will be described later.

[0041] The band-pass filter 22 has the characteristic of selectively transmitting the wavelength band of the green light LG and absorbing and cutting off the red light LR and the near-infrared light LI which are lights in other wavelength bands. The band-pass filter 22 is formed, for example, by alternately laminating a plurality of low refractive index layers such as silicon oxide and high refractive index layers such as titanium oxide on the first angle limiting filter 21.

[0042] For example, a part of the red light LR and the near-infrared light LI emitted from the second light emitting element 60 may pass through the living body and enter the first light receiving element 51. In the case of the present embodiment, the first light receiving element 51 includes the band-pass filter 22 that selectively transmits the green light LG. Therefore, the first light receiving element 51 can cut off the red light LR and the near-infrared light LI having wavelength bands different from that of the green light LG. Thus, the first light receiving element 51 can efficiently receive the green light LG emitted from the first light emitting element 50.

[0043] Further, the second light receiving element 61 includes a sensor 30 that receives the red light LR or the near-infrared light LI, and a second angle limiting filter (angle limiting member) 31 that limits the incident angle of the red light LR or the near-infrared light LI reaching the sensor 30. That is, in the detection device 3 of the present embodiment, the second light receiving element 61 has a configuration different from that of the first light receiving element 51 in that it does not include a band-pass filter that selectively transmits the red light LR or the near-infrared light LI.

[0044] The sensor 30 is composed of, for example, a photodiode. The second angle limiting filter 31 is provided so as to cover the entire light receiving surface 30a of the sensor 30. The second angle limiting filter 31 can limit the incident angle of the red light LR or the near-infrared light LI reaching the sensor 30. The second angle-limiting filter 31 transmits, for example, red light LR or near-infrared light LI that propagates in the living body and enters at an acceptable incident angle, guiding it to the sensor 30, and cuts off light that enters at an angle greater than the acceptable incident angle, such as external light like sunlight or red light LR or near-infrared light LI that did not pass through the living body, so that it does not enter the sensor 30. That is, the second angle-limiting filter 31 is an angle-limiting member that limits the incident angle with respect to the sensor 30 in the red light LR or near-infrared light LI from the second light-emitting element 60 or the third light-emitting element 70. The details of the configuration of the second angle-limiting filter 31 will be described later.

[0045] FIG. 5 is a diagram showing the behavior of the light emitted from the light-emitting unit 11. As shown in FIG. 5, a part of the green light LG emitted from the first light-emitting element 50 may be directly incident on the first light-receiving element 51 without reaching the blood vessel M1 inside the living body by being reflected, for example, on the surface layer of the living body (measurement site M). In addition, external light such as sunlight may be directly incident on the first light-receiving element 51 from the gap between the living body and the detection surface 16. The green light LG that travels toward the first light-receiving element 51 without reaching the blood vessel M1 is referred to as the "first stray light component SL1", and the external light that directly travels toward the first light-receiving element 51 is referred to as the "second stray light component SL2".

[0046] Since the first stray light component SL1 has a green wavelength band, it passes through the band-pass filter 22 and enters the first angle-limiting filter 21 provided below the band-pass filter 22. As described above, the first angle-limiting filter 21 has the characteristic of transmitting light that enters at an angle smaller than the acceptable incident angle and cutting off light that enters at an angle greater than the acceptable incident angle.

[0047] Since the first stray light component SL1 enters the first light receiving element 51 without reaching the blood vessel M1, the incident angle of the first stray light component SL1 with respect to the first light receiving element 51 is larger than the allowable incident angle of the first angle limiting filter 21. That is, the first stray light component SL1 is cut by the first angle limiting filter 21. Thereby, the first light receiving element 51 can suppress the incidence of the first stray light component SL1 on the light receiving surface 20a of the sensor 20 by the first angle limiting filter 21.

[0048] The second stray light component SL2 is generally cut by the band-pass filter 22, but the component having the green wavelength band included in the second stray light component SL2 passes through the band-pass filter 22. Here, since the second stray light component SL2 enters from the gap between the living body and the detection surface 16 as described above, the incident angle of the second stray light component SL2 with respect to the first light receiving element 51 is larger than the allowable incident angle of the first angle limiting filter 21. Therefore, a part of the second stray light component SL2 (the component having the green wavelength band) that has passed through the band-pass filter 22 is cut by the first angle limiting filter 21. Thereby, the first light receiving element 51 can suppress the incidence of the second stray light component SL2 on the light receiving surface 20a of the sensor 20 by the first angle limiting filter 21.

[0049] On the other hand, the green light LG propagated in the blood vessel M1 passes through the band-pass filter 22 and enters the first angle limiting filter 21 provided under the band-pass filter 22 at a predetermined angle. Since the green light LG propagated in the blood vessel M1 is emitted from the inside of the living body as compared with the first stray light component SL1 reflected on the surface layer of the living body, it enters the first light receiving element 51 at a smaller incident angle, that is, enters from a direction closer to the normal direction.

[0050] Generally, the acceptance incident angle of the angle-limiting filter is designed to be smaller than the incident angle with respect to the light-receiving part of the light propagating in the blood vessel. The angle-limiting filter is formed, for example, by embedding a light-shielding wall made of a light-shielding material such as tungsten in a silicon oxide layer having light permeability using a semiconductor process. Conventionally, a general angle-limiting filter was configured by embedding light-shielding walls arranged at equal intervals in a silicon oxide layer.

[0051] Based on simulations, the inventors have found that when using a conventional angle-limiting filter in which light-shielding walls are embedded at equal intervals in a silicon oxide layer, the light that has passed through the living body cannot be efficiently incident on the light-receiving surface of the sensor of the light-receiving part.

[0052] In a light-receiving element using an angle-limiting filter in which light-shielding walls are embedded at equal intervals as in the conventional configuration, a light-incidence region where green light LG is concentrated and incident is formed on the light-receiving surface on the side of the first light-emitting element 50, and the amount of received green light LG incident on the light-receiving surface away from the first light-emitting element 50 decreases. That is, when using an angle-limiting filter in which light-shielding walls are embedded at equal intervals as in the conventional case, the amount of light received by the light-receiving element varies within the plane.

[0053] FIG. 6 is a graph showing the transmission spectrum of the skin. In FIG. 6, the horizontal axis represents the wavelength of light, and the vertical axis represents the transmittance (unit: %). FIG. 6 shows a transmission spectrum in the case where the skin thickness is 0.43 mm as an example.

[0054] As shown in FIG. 6, the transmittance when the wavelength band of green light LG (for example, 520 nm) is incident on the skin is about 30%, the transmittance when the wavelength band of red light LR (for example, 660 nm) is incident on the skin is about 50% - 60%, and the transmittance when the wavelength band of near-infrared light LI (for example, 905 nm) is incident on the skin is about 60%.

[0055] The graph shown in Fig. 6 shows that the distance that can be propagated in vivo varies for each wavelength of light. That is, according to the graph of Fig. 6, it can be seen that green light LG can propagate only a short distance in vivo compared to red light LR or near-infrared light LI. In other words, it can be said that red light LR and near-infrared light LI can propagate further in vivo than green light LG. In Fig. 6, the case where the skin thickness is 0.43 mm is taken as an example, but even when the skin thickness is different, similarly, red light LR and near-infrared light LI can propagate further in vivo than green light LG.

[0056] As shown in the graph of Fig. 6, the inventors have obtained the finding that green light LG is more easily attenuated when passing through the living body compared to red light LR and near-infrared light LI. Therefore, in a light-receiving element using an angle-limiting filter in which light-shielding walls are embedded at equal intervals as in the prior art, the green light LG is more easily attenuated in the living body before reaching the light-receiving surface as the distance from the first light-emitting element 50 increases. As a result, it was considered that there would be variations in the light-receiving amount within the plane of the light-receiving surface in the X-axis direction away from the first light-emitting element 50.

[0057] Therefore, the inventors focused on the structure of the angle-limiting filter and completed the detection device 3 of the present embodiment that can suppress variations in the light-receiving amount in the light-receiving element.

[0058] Fig. 7 is a cross-sectional view showing the main configuration of the detection device 3 of the present embodiment. As shown in Fig. 7, the first light-receiving element 51 has a plurality of light-receiving regions. The plurality of light-receiving regions include a first light-receiving region IA1, a second light-receiving region IB1, a third light-receiving region IC1, and a fourth light-receiving region ID1. Hereinafter, when the first light-receiving region IA1, the second light-receiving region IB1, the third light-receiving region IC1, and the fourth light-receiving region ID1 are not particularly distinguished, they are collectively referred to as "each light-receiving region IA1, IB1, IC1, ID1".

[0059] Each light-receiving region IA1, IB1, IC1, ID1 is provided on the light-receiving surface 20a of the sensor 20 of the first light-receiving element 51. Specifically, the first light-receiving region IA1 is the region located on the light-receiving surface 20a of the sensor 20 that is closest to the light-emitting unit portion 11 (-X side). The second light-receiving region IB1 is a region spaced +X side from the light-emitting unit portion 11 farther than the first light-receiving region IA1, the third light-receiving region IC1 is a region spaced +X side from the light-emitting unit portion 11 farther than the second light-receiving region IB1, and the fourth light-receiving region ID1 is a region spaced +X side from the light-emitting unit portion 11 farther than the third light-receiving region IC1. That is, the light-receiving regions IA1, IB1, IC1, ID1 are arranged side by side on the light-receiving surface 20a in this order on the +X side.

[0060] The first angle-limiting filter 21 includes a first limiting region 21A, a second limiting region 21B, a third limiting region 21C, and a fourth limiting region 21D. Hereinafter, when the first limiting region 21A, the second limiting region 21B, the third limiting region 21C, and the fourth limiting region 21D are not particularly distinguished, these are collectively referred to as "each limiting region 21A, 21B, 21C, 21D".

[0061] Each limiting region 21A, 21B, 21C, 21D corresponds to each light-receiving region IA1, IB1, IC1, ID1. When viewed in plan from the +Z side, the first limiting region 21A is arranged to overlap the first light-receiving region IA1, and limits the incident angle of the green light LG with respect to the first light-receiving region IA1 of the first light-receiving element 51. When viewed in plan from the +Z side, the second limiting region 21B is arranged to overlap the second light-receiving region IB1, and limits the incident angle of the green light LG with respect to the second light-receiving region IB1 of the first light-receiving element 51. When viewed in plan from the +Z side, the third limiting region 21C is arranged to overlap the third light-receiving region IC1, and limits the incident angle of the green light LG with respect to the third light-receiving region IC1 of the first light-receiving element 51. When viewed in plan from the +Z side, the fourth limiting region 21D is arranged to overlap the fourth light-receiving region ID1, and limits the incident angle of the green light LG with respect to the fourth light-receiving region ID1 of the first light-receiving element 51.

[0062] In this embodiment, the degree of angular limitation in the second limitation region 21B is smaller than the degree of angular limitation in the first limitation region 21A. Also, the degree of angular limitation in the third limitation region 21C is smaller than the degree of angular limitation in the second limitation region 21B. Further, the degree of angular limitation in the fourth limitation region 21D is smaller than the degree of angular limitation in the third limitation region 21C. That is, in the detection device 3 of this embodiment, as the respective limitation regions 21A, 21B, 21C, 21D are spaced apart from the first light emitting element 50, the degree of angular limitation of each becomes smaller.

[0063] Here, when the degree of angular limitation is "small", it means that light incident at a large incident angle (a lying angle away from the vertical direction) with respect to the first light emitting element can reach the light receiving surface 20a of the sensor 20, that is, the allowable incident angle is large. On the other hand, when the degree of angular limitation is "large", it means that light incident at a small incident angle (an upright angle close to the vertical direction) with respect to the first light receiving element 51 can reach the light receiving surface 20a of the sensor 20, that is, the allowable incident angle is small.

[0064] The first angular limitation filter 21 includes a silicon oxide layer 24 and a plurality of light shielding walls (first light shielding walls) 25 embedded in the silicon oxide layer 24. Each light shielding wall 25 is formed in a plate shape extending from the light receiving surface 20a of the sensor 20 toward the +Z side. Although omitted in FIG. 7, the plurality of light shielding walls 25 are arranged in the Y-axis direction in addition to the X-axis direction, and are arranged so as to form a lattice shape as a whole when viewed in plan from the +Z side.

[0065] The first angle limiting filter 21 is formed, for example, by embedding a light shielding wall 25 made of a conductive plug such as a tungsten plug having light absorptivity into a silicon oxide layer 24 in a wiring formation process of a semiconductor process. The silicon oxide layer 24 forms an optical path for guiding light to the light receiving surface 20a of the sensor 20. The light shielding wall 25 embedded in the silicon oxide layer 24 limits the incident angle of light passing through the optical path (silicon oxide layer 24). That is, when the light incident on the silicon oxide layer 24 is inclined with respect to the optical path by more than a predetermined angle, the incident light hits the light shielding wall 25, a part of the light is absorbed by the light shielding wall 25, and the rest is reflected. And since the intensity of the reflected light becomes weak by the reflection being repeated until it passes through the optical path, the light that can finally pass through the first angle limiting filter 21 is substantially limited to the light whose inclination with respect to the optical path is within a predetermined limiting angle. Based on such a configuration, the first angle limiting filter 21 functions as an angle limiting member that limits the incident angle with respect to the sensor 20 in the green light LG from the first light emitting element 50.

[0066] In the first angle limiting filter 21 of the present embodiment, the plurality of light shielding walls 25 are provided on each light receiving region IA1, IB1, IC1, ID1 of the first light receiving element 51. The plurality of light shielding walls 25 include light shielding walls 25a, 25b, 25c, 25d, 25e.

[0067] The light shielding wall 25a and the light shielding wall 25b partition the first limiting region 21A in the X-axis direction. The light shielding wall 25b and the light shielding wall 25c partition the second limiting region 21B in the X-axis direction. The light shielding wall 25c and the light shielding wall 25d partition the third limiting region 21C in the X-axis direction. The light shielding wall 25d and the light shielding wall 25e partition the fourth limiting region 21D in the X-axis direction.

[0068] The degree of angle limitation in each of the limiting regions 21A, 21B, 21C, 21D is defined by the interval between adjacent light shielding walls in the X-axis direction.

[0069] In the present embodiment, a plurality of light-shielding walls that limit the incident angle of light to the light-receiving unit portion 12 are arranged in the X-axis direction, and the interval between the light-shielding walls in the region far from the light-emitting unit portion 11 is larger than the interval between the light-shielding walls in the region close to the light-emitting unit portion 11. Specifically, among the plurality of light-shielding walls 25, the interval between the light-shielding walls 25b and 25c adjacent to each other in the X-axis direction in the second restricted region 21B is larger than the interval between the light-shielding walls 25a and 25b adjacent to each other in the X-axis direction in the first restricted region 21A among the plurality of light-shielding walls 25. Also, among the plurality of light-shielding walls 25, the interval between the light-shielding walls 25c and 25d adjacent to each other in the X-axis direction in the third restricted region 21C is larger than the interval between the light-shielding walls 25b and 25c adjacent to each other in the X-axis direction in the second restricted region 21B among the plurality of light-shielding walls 25. Also, among the plurality of light-shielding walls 25, the interval between the light-shielding walls 25d and 25e adjacent to each other in the X-axis direction in the fourth restricted region 21D is larger than the interval between the light-shielding walls 25c and 25d adjacent to each other in the X-axis direction in the third restricted region 21C among the plurality of light-shielding walls 25.

[0070] In the case of the present embodiment, for example, the interval between the light-shielding walls 25a and 25b is set to 3 μm, the interval between the light-shielding walls 25b and 25c is set to 4.5 μm, the interval between the light-shielding walls 25c and 25d is set to 6 μm, and the interval between the light-shielding walls 25d and 25e is set to 7.5 μm. Also, the heights of the light-shielding walls 25a, 25b, 25c, 25d, and 25e are each set to 5 μm.

[0071] As shown in FIG. 7, since the second restricted region 21B has a wider interval in the X-axis direction than the first restricted region 21B, the allowable incident angle of the second restricted region 21B is larger than the allowable incident angle of the first restricted region 21A. In the first angle-limiting filter 21 of the present embodiment, by adjusting the interval between the adjacent light-shielding walls in the X-axis direction as described above, the angle-limiting degree in the second restricted region 21B is made smaller than the angle-limiting degree in the first restricted region 21A.

[0072] In addition, since the third restricted region 21C has a wider interval in the X-axis direction than the second restricted region 21B, the allowable incident angle of the third restricted region 21C is larger than that of the second restricted region 21B. In the first angle limiting filter 21 of the present embodiment, by adjusting the interval between adjacent light shielding walls in the X-axis direction as described above, the degree of angle limitation in the third restricted region 21C is made smaller than the degree of angle limitation in the second restricted region 21B.

[0073] In addition, since the fourth restricted region 21D has a wider interval in the X-axis direction than the third restricted region 21C, the allowable incident angle of the fourth restricted region 21D is larger than that of the third restricted region 21C. In the first angle limiting filter 21 of the present embodiment, by adjusting the interval between adjacent light shielding walls in the X-axis direction as described above, the degree of angle limitation in the fourth restricted region 21D is made smaller than the degree of angle limitation in the third restricted region 21C.

[0074] Thus, by providing the first light receiving element 51 of the present embodiment with the first angle limiting filter 21, the degree of angle limitation (allowable incident angle) in the first light receiving element 51 becomes smaller as it moves away from the first light emitting element 50 toward the +X side.

[0075] As shown in FIG. 5, the green light LG that has propagated in the blood vessel M1 is emitted in a state of being scattered from the living body. Therefore, the green light LG that has propagated in the blood vessel M1 contains a scattering component. A part of such a scattering component includes a scattering component LG1 that travels toward the +X side more than the specular reflection component from the living body.

[0076] The scattering component LG1 has a larger incident angle with respect to the first light receiving element 51 than the specular reflection component of the green light LG that has propagated in the blood vessel M1 and is emitted. That is, the inclination with respect to the normal direction of the light receiving surface 20a of the sensor 20 is large. Therefore, in the case of the angle-limiting filter in which the light-shielding walls are embedded at equal intervals, since the degree of angle limitation is constant in the X-axis direction, the scattered component LG1 with an incident angle larger than the specular reflection component of the green light LG is cut off by the light-shielding walls and cannot be incident on the light-receiving surface 20a of the sensor 20.

[0077] On the other hand, in the first angle-limiting filter 21 of the present embodiment, the degree of angle limitation of the first light-receiving element 51 (the light-receiving surface 20a of the sensor 20) becomes smaller as it goes toward the +X side. That is, since the allowable incident angle on the +X side of the first light-receiving element 51 is larger than the allowable incident angle on the -X side, even the scattered component LG1 with a large inclination with respect to the normal direction of the light-receiving surface 20a of the sensor 20 can be transmitted. The first angle-limiting filter 21 can, for example, cause the scattered component LG1 to be incident on the light-receiving surface 20a of the sensor 20 through the third limiting region 21C or the fourth limiting region 21D having a relatively large allowable incident angle.

[0078] According to the first light-receiving element 51 of the present embodiment, since the first angle-limiting filter 21 with a smaller degree of angle limitation as it is separated from the +X side of the first light-emitting element 50 is provided, the scattered component LG1 that is cut off by the conventional angle-limiting filter can be taken into the sensor 20. Therefore, the first light-receiving element 51 can reduce the variation in the amount of light received within the plane of the light-receiving surface 20a of the sensor 20, and can achieve high detection accuracy by efficiently taking in the green light LG emitted from the light-emitting unit portion 11 into the sensor 20.

[0079] Here, in the detection device 3 of the present embodiment, as shown in FIG. 5, a part of the red light LR emitted from the second light-emitting element 60 or a part of the near-infrared light LI emitted from the third light-emitting element 70 may directly enter the second light-receiving element 61 without passing through the living body. In addition, external light such as sunlight may directly enter the second light-receiving element 61 from the gap between the living body and the detection surface 16. Hereinafter, the red light LR or the near-infrared light LI that directly travels toward the second light-receiving element 61 without passing through the living body is collectively referred to as the "third stray light component SL3", and the external light that directly travels toward the second light-receiving element 61 is referred to as the "fourth stray light component SL4".

[0080] Since the third stray light component SL3 enters the second angle-limiting filter 31 without passing through the living body, the incident angle of the third stray light component SL3 with respect to the second light-receiving element 61 is larger than the allowable incident angle of the second angle-limiting filter 31. In addition, since the fourth stray light component SL4 enters from the gap between the living body and the detection surface 16, the incident angle of the fourth stray light component SL4 with respect to the second light-receiving element 61 is larger than the allowable incident angle of the angle-limiting filter 31.

[0081] Therefore, the third stray light component SL3 and the fourth stray light component SL4 are well cut by the second angle-limiting filter 31. As a result, the second light-receiving element 61 can suppress the incidence of the third stray light component SL3 and the fourth stray light component SL4 on the light-receiving surface 30a of the sensor 30 by the second angle-limiting filter 31.

[0082] The second light-receiving element 61 has the same configuration as the first light-receiving element 51. The second light-receiving element 61 has a plurality of light-receiving regions including a first light-receiving region IA2, a second light-receiving region IB2, and a third light-receiving region IC2. Hereinafter, when the first light-receiving region IA2, the second light-receiving region IB2, and the third light-receiving region IC2 are not particularly distinguished, these are collectively referred to as "each light-receiving region IA2, IB2, IC2".

[0083] Each light-receiving region IA2, IB2, IC2 corresponds to a part of the light-receiving surface 30a of the sensor 30 of the second light-receiving element 61. Each light-receiving region IA2, IB2, IC2 is arranged side by side on the +X side on the light-receiving surface 30a in this order. In this embodiment, the number of light-receiving regions (three) of the second light-receiving element 61 is different from the number of light-receiving regions (four) of the first light-receiving element 51.

[0084] The second angle-limiting filter 31 has the same configuration as the first angle-limiting filter 21. The second angle-limiting filter 31 includes a first limiting region 31A, a second limiting region 31B, and a third limiting region 31C. Hereinafter, when the first limiting region 31A, the second limiting region 31B, and the third limiting region 31C are not particularly distinguished, they are collectively referred to as "each limiting region 31A, 31B, 31C".

[0085] Each limiting region 31A, 31B, 31C corresponds to each light-receiving region IA2, IB2, IC2. When viewed in plan from the +Z side, the first limiting region 31A is arranged so as to overlap the first light-receiving region IA2, and limits the incident angle of red light LR or near-infrared light LI with respect to the first light-receiving region IA2 of the second light-receiving element 61. When viewed in plan from the +Z side, the second limiting region 31B is arranged so as to overlap the second light-receiving region IB2, and limits the incident angle of red light LR or near-infrared light LI with respect to the second light-receiving region IB2 of the second light-receiving element 61. When viewed in plan from the +Z side, the third limiting region 31C is arranged so as to overlap the third light-receiving region IC2, and limits the incident angle of red light LR or near-infrared light LI with respect to the third light-receiving region IC2 of the second light-receiving element 61.

[0086] In the detection device 3 of this embodiment, as each limiting region 31A, 31B, 31C is separated from the light-emitting elements 60, 70, the degree of angle limitation of each becomes smaller.

[0087] The second angle-limiting filter 31 includes a silicon oxide layer 34 and a plurality of light-shielding walls (second light-shielding walls) 35 embedded in the silicon oxide layer 34. Each light-shielding wall 35 is formed in a plate shape extending from the light-receiving surface 30a of the sensor 30 toward the +Z side. Although omitted in FIG. 7, the plurality of light-shielding walls 35 are arranged not only in the X-axis direction but also in the Y-axis direction, so that they are arranged in a lattice shape as a whole when viewed in plan from the +Z side. Note that the second angle-limiting filter 31 is formed by a wiring formation process of the same semiconductor process as the first angle-limiting filter 21.

[0088] The plurality of light-shielding walls 35 include light-shielding walls 35a, 35b, 35c, and 35d. The light-shielding wall 35a and the light-shielding wall 35b partition the first restriction region 31A in the X-axis direction. The light-shielding wall 35b and the light-shielding wall 35c partition the second restriction region 31B in the X-axis direction. The light-shielding wall 35c and the light-shielding wall 35d partition the third restriction region 31C in the X-axis direction. The degree of angle limitation in each of the restriction regions 31A, 31B, and 31C is defined by the interval between adjacent light-shielding walls in the X-axis direction.

[0089] In the present embodiment, the interval between the light-shielding walls 35b and 35c adjacent to each other in the X-axis direction in the second restriction region 31B among the plurality of light-shielding walls 35 is larger than the interval between the light-shielding walls 35a and 35b adjacent to each other in the X-axis direction in the first restriction region 31A among the plurality of light-shielding walls 35. Also, the interval between the light-shielding walls 35c and 35d adjacent to each other in the X-axis direction in the third restriction region 31C among the plurality of light-shielding walls 35 is larger than the interval between the light-shielding walls 35b and 35c adjacent to each other in the X-axis direction in the second restriction region 31B among the plurality of light-shielding walls 35.

[0090] In the case of the present embodiment, for example, the interval between the light-shielding walls 35a and 35b is set to 4.5 μm, the interval between the light-shielding walls 35b and 35c is set to 6 μm, and the interval between the light-shielding walls 35c and 35d is set to 7.5 μm. Also, the heights of the light-shielding walls 35a, 35b, 35c, and 35d are each set to 5 μm.

[0091] As shown in Fig. 7, the second light-receiving element 61 of the present embodiment includes the second angle-limiting filter 31, so that the degree of angle limitation (allowable incident angle) in the second light-receiving element 61 becomes smaller as the distance from the light-emitting elements 60 and 70 to the +X side increases.

[0092] Here, although the light-emitting elements 50, 60, and 70 (light-emitting unit portion 11) that emit green light LG, red light LR, and near-infrared light LI are arranged at the same position in the X-axis direction, the second light-receiving element 61 that receives red light LR or near-infrared light LI is arranged at a position separated from the first light-receiving element 51 that receives green light LG by a distance toward the +X side, as shown in Fig. 5. Since the second light-receiving element 61 is arranged at a position separated from the light-emitting unit portion 11 in the X-axis direction with respect to the first light-receiving element 51 in this way, the incident angle of red light LR or near-infrared light LI with respect to the second light-receiving element 61 becomes larger than the incident angle of green light LG with respect to the first light-receiving element 51.

[0093] In the case of the present embodiment, the degree of angle limitation of the first limiting region 31A in the second angle-limiting filter 31 is smaller than the degree of angle limitation of the first limiting region 21A in the first angle-limiting filter 21. Specifically, the distance between the light-shielding walls 35a and 35b adjacent to each other in the X-axis direction in the first limiting region 31A is larger than the distance between the light-shielding walls 25a and 25b adjacent to each other in the X-axis direction in the first limiting region 21A.

[0094] That is, the allowable incident angle of the first limiting region 31A in the second angle-limiting filter 31 is larger than the allowable incident angle of the first limiting region 21A in the first angle-limiting filter 21. By relatively increasing the allowable incident angle of the first limiting region 31A located on the light-emitting unit portion 11 side in the second angle-limiting filter 31 in this way, as described above, red light LR or near-infrared light LI incident at a large angle with respect to the second light-receiving element 61 can be made to enter the light-receiving surface 30a of the sensor 30 without being cut off.

[0095] Also, as shown in FIG. 5, since the red light LR or near-infrared light LI propagated in the blood vessel M1 is emitted in a state scattered from the living body, it contains scattering components. Some of such scattering components include scattering components LR1, LI1 that are directed toward the +X side rather than the specular reflection component from the living body.

[0096] The scattering components LR1, LI1 have a larger incident angle with respect to the second light receiving element 61 than the specular reflection component of the red light LR or near-infrared light LI propagated in the blood vessel M1 and emitted. In the second angle limiting filter 31 of the present embodiment, by making the angle limiting degree of the second light receiving element 61 (light receiving surface 30a of the sensor 30) smaller as it goes toward the +X side, the allowable incident angle on the +X side is made larger than the allowable incident angle on the -X side. Thereby, the second angle limiting filter 31 can make the scattering components LR1, LI1 enter the light receiving surface 30a of the sensor 30 through, for example, the second limiting region 31B or the third limiting region 31C that is located on the +X side and has a relatively large allowable incident angle.

[0097] According to the second light receiving element 61 of the present embodiment, since it includes the second angle limiting filter 31 whose angle limiting degree becomes smaller as it is separated from the light emitting elements 60, 70 toward the +X side, the scattering components LR1, LI1 that would be cut off by a conventional angle limiting filter can be taken into the sensor 30. Therefore, the second light receiving element 61 can achieve high detection accuracy by efficiently taking the red light LR or near-infrared light LI emitted from the light emitting unit portion 11 into the sensor 30 by reducing the variation in the amount of light received within the plane of the light receiving surface 30a of the sensor 30.

[0098] Also, in the detection device 3 of the present embodiment, the distance D1 between the first light emitting element 50 and the first light receiving element 51 is made smaller than the distance (distance D2 or distance D3) between the second light emitting element 60 or the third light emitting element 70 and the second light receiving element 61.

[0099] ]In the case of this embodiment, since the first light receiving element 51 is arranged at the closest position to the first light emitting element 50, it is possible to efficiently receive the green light LG that propagates in the living body and is incident on the first light receiving element 51. Further, as described above, the red light LR and the near-infrared light LI can propagate further in the living body than the green light LG. Therefore, the second light receiving element 61 can also efficiently receive the red light LR and the near-infrared light LI that have propagated a longer distance in the living body than the green light LG. Thus, the detection device 3 of this embodiment can accurately detect the green light LG, the red light LR, and the near-infrared light LI that have propagated in the living body by the light receiving unit 12.

[0100] In the detection device 3 of this embodiment, the distance that the red light LR and the near-infrared light LI propagate in the living body before being incident on the second light receiving element 61 is larger than the distance that the green light LG propagates in the living body before being incident on the first light receiving element 51.

[0101] As described above, the green light LG can propagate only a short distance in the living body compared to the red light LR or the near-infrared light LI. Therefore, if the green light LG propagates in the living body so as to reach the second light receiving element 61, the green light LG will be in a state of being sufficiently attenuated when passing through the living body. Thus, the green light LG cannot be incident on the second light receiving element 61.

[0102] On the other hand, the red light LR and the near-infrared light LI can propagate further in the living body than the green light LG. Therefore, the red light LR and the near-infrared light LI can be incident on the second light receiving element 61, which is farther from the light emitting unit 11, with a sufficient amount of light even when they propagate a longer distance in the living body than the green light LG.

[0103] In the case of this embodiment, since only red light LR and near-infrared light LI are incident on the second light-receiving element 61, it is not necessary to provide a band-pass filter that selectively transmits red light LR and near-infrared light LI and cuts green light LG to the second light-receiving element 61. That is, in the detection device 3 of this embodiment, only the first light-receiving element 51 includes the band-pass filter 22, and the above configuration in which the second light-receiving element 61 does not include a band-pass filter can be adopted. Therefore, the detection device 3 of this embodiment can reduce costs by omitting the band-pass filter of the second light-receiving element 61.

[0104] The first light-receiving element 51 of this embodiment can 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 20a of the sensor 20. Therefore, the first light-receiving element 51 can obtain a high S / N ratio by suppressing the incidence of the first stray light component SL1 and the second stray light component SL2 that become noise components. In addition, the second light-receiving element 61 of this embodiment can make it difficult for the third stray light component SL3 and the fourth stray light component SL4 to be incident on the light-receiving surface 30a of the sensor 30. Therefore, the second light-receiving element 61 can obtain a high S / N ratio by suppressing the incidence of the third stray light component SL3 and the fourth stray light component SL4 that become noise components.

[0105] As described above, according to the detection device 3 of this embodiment, by increasing the S / N ratio and increasing the amount of received light, the detection accuracy of the light-receiving unit 12 can be greatly improved. Therefore, in the detection device 3 of this embodiment, since high-precision light reception is possible in each light-receiving element 51, 61, the power consumption of the light-emitting unit 11 can be suppressed by suppressing the light emission amount of each light-emitting element 50, 60, 70. According to the measuring device 100 of this embodiment, by including the detection device 3, it is possible to provide a biological measurement device that enables high-precision detection while suppressing power consumption.

[0106] (Second Embodiment) Next, the detection device of the second embodiment will be described. The configuration of the first angle limiting filter and the second angle limiting filter as the angle limiting members of the detection device of this embodiment is different from that of the first embodiment. Hereinafter, the same reference numerals will be given to the configurations and members common to the first embodiment, and the details will be omitted.

[0107] FIG. 8 is a cross-sectional view showing the main configuration of the detection device 103 of this embodiment. As shown in FIG. 8, the detection device 103 of this embodiment further includes a light emitting unit 11, a light receiving unit 112, a case 40, and a sealing layer 42. The light receiving unit 112 of this embodiment has a first light receiving element 151 and a second light receiving element 161.

[0108] The first light receiving element 151 includes a sensor 20, a first angle limiting filter (angle limiting member) 81, and a bandpass filter 22. The second light receiving element 161 includes a sensor 30 and a second angle limiting filter (angle limiting member) 91.

[0109] In the detection device 103 of this embodiment, the first light receiving element 151 includes a first light receiving region IA11, a second light receiving region IB11, and a third light receiving region IC11. Hereinafter, when the first light receiving region IA11, the second light receiving region IB11, and the third light receiving region IC1 are not particularly distinguished, these are collectively referred to as "each light receiving region IA11, IB11, IC11". Each light receiving region IA11, IB11, IC11 corresponds to a part of the light receiving surface 20a of the sensor 20 of the first light receiving element 151. Each light receiving region IA11, IB11, IC11 is arranged side by side on the +X side on the light receiving surface 20a of the sensor 20 in this order.

[0110] The first angle limiting filter 81 includes a first limiting region 81A, a second limiting region 81B, and a third limiting region 81C. Hereinafter, when the first limiting region 81A, the second limiting region 81B, and the third limiting region 81C are not particularly distinguished, these are collectively referred to as "each limiting region 81A, 81B, 81C".

[0111] Each of the restricted areas 81A, 81B, and 81C corresponds to each of the light-receiving areas IA11, IB11, and IC11. In the detection device 103 of the present embodiment, as the restricted areas 81A, 81B, and 81C are separated from the first light-emitting element 50, the degree of angular restriction of each becomes smaller.

[0112] The first angular restriction filter 81 includes a silicon oxide layer 84 and a plurality of light-shielding walls (first light-shielding walls) 85 embedded in the silicon oxide layer 84. In the first angular restriction filter 81, the plurality of light-shielding walls 85 are provided on each of the light-receiving areas IA1, IB1, and IC1 of the first light-receiving element 151. The plurality of light-shielding walls 85 include light-shielding walls 85a, 85b, 85c, 85d, 85e, 85f, and 85g.

[0113] The light-shielding wall 85a and the light-shielding wall 85b are arranged in the X-axis direction in the first restricted area 81A. In the case of the present embodiment, for example, the height of each of the light-shielding wall 85a and the light-shielding wall 85b is set to 5 μm.

[0114] The light-shielding wall 85c and the light-shielding wall 85d are arranged in the X-axis direction in the second restricted area 81B. In the case of the present embodiment, for example, the height of each of the light-shielding wall 85c and the light-shielding wall 85d is set to 4 μm.

[0115] The light-shielding wall 85e, the light-shielding wall 85f, and the light-shielding wall 85g are arranged in the X-axis direction in the third restricted area 81C. In the case of the present embodiment, for example, the height of each of the light-shielding wall 85e, the light-shielding wall 85f, and the light-shielding wall 85g is set to 3 μm. Note that, for example, the interval in the X-axis direction between adjacent walls among the light-shielding walls 85a, 85b, 85c, 85d, 85e, 85f, and 85g is set to 3 μm.

[0116] The first angular restriction filter 81 of the present embodiment can be formed by embedding a plurality of light-shielding walls 85 having different heights in the silicon oxide layer 24, for example, by dividing the wiring formation process of the semiconductor process into a plurality of times and providing a portion for embedding a conductive plug such as a tungsten plug having light absorption and a portion not to be embedded.

[0117] In the case of this embodiment, the degree of angle limitation in each of the restriction regions 81A, 81B, and 81C is defined by the height of the light-shielding walls arranged in the X-axis direction.

[0118] In this embodiment, among the plurality of light-shielding walls 85, the heights of the light-shielding walls 85c and 85d arranged in the X-axis direction in the second restriction region 81B are lower than the heights of the light-shielding walls 85a and 85b arranged in the X-axis direction in the first restriction region 81A among the plurality of light-shielding walls 85. Also, among the plurality of light-shielding walls 85, the heights of the light-shielding walls 85e, 85f, and 85g arranged in the X-axis direction in the third restriction region 81C are lower than the heights of the light-shielding walls 85c and 85d arranged in the X-axis direction in the second restriction region 81B among the plurality of light-shielding walls 85.

[0119] As shown in FIG. 8, since the height of the light-shielding wall in the second restriction region 81B is lower than that in the first restriction region 81A, the allowable incident angle in the second restriction region 81B is larger than the allowable incident angle in the first restriction region 81A. In the first angle-limiting filter 81 of this embodiment, by adjusting the height of the light-shielding walls arranged in the X-axis direction as described above, the degree of angle limitation in the second restriction region 81B is made smaller than the degree of angle limitation in the first restriction region 81A.

[0120] Also, since the height of the light-shielding wall in the third restriction region 81C is lower than that in the second restriction region 81B, the allowable incident angle in the third restriction region 81C is larger than the allowable incident angle in the second restriction region 81B. In the first angle-limiting filter 81 of this embodiment, by adjusting the height of the light-shielding walls arranged in the X-axis direction as described above, the degree of angle limitation in the third restriction region 81C is made smaller than the degree of angle limitation in the second restriction region 81B.

[0121] Thus, by providing the first light-receiving element 151 of this embodiment with the first angle-limiting filter 81, the degree of angle limitation (allowable incident angle) in the first light-receiving element 151 becomes smaller as the distance from the first light-emitting element 50 to the +X side increases.

[0122] According to the first angle limiting filter 81 of this embodiment, for example, the scattered component LG1 can be made incident on the light receiving surface 20a of the sensor 20 via the second limiting region 81B or the third limiting region 81C, which have a relatively large allowable incident angle.

[0123] According to the first light receiving element 151 of this embodiment, the first angle limiting filter 81 has a degree of angle limiting that decreases the further away from the first light emitting element 50 it is on the +X side, so that the scattered component LG1 that is cut by a conventional angle limiting filter can be captured by the sensor 20. Therefore, the first light receiving element 151 reduces the variation in the amount of light received within the light receiving surface 20a of the sensor 20, thereby efficiently capturing the green light LG emitted from the light emitting unit 11 into the sensor 20, thereby achieving high detection accuracy.

[0124] The second light receiving element 161 has the same configuration as the first light receiving element 151 . The second light receiving element 161 has multiple light receiving regions including a first light receiving region IA21, a second light receiving region IB21, and a third light receiving region IC21. Hereinafter, when there is no particular distinction between the first light receiving region IA21, the second light receiving region IB21, and the third light receiving region IC21, they will be collectively referred to as the "respective light receiving regions IA21, IB21, and IC21."

[0125] Each of the light receiving regions IA21, IB21, and IC21 corresponds to a part of the light receiving surface 30a of the sensor 30 of the second light receiving element 161. The light receiving regions IA21, IB21, and IC21 are arranged side by side in this order on the +X side of the light receiving surface 30a of the sensor 30.

[0126] The second angle limiting filter 91 has the same configuration as the first angle limiting filter 81 . The second angle limiting filter 91 includes a first restriction area 91A, a second restriction area 91B, and a third restriction area 91C. Hereinafter, when the first restriction area 91A, the second restriction area 91B, and the third restriction area 91C are not particularly distinguished from each other, they will be collectively referred to as the "respective restriction areas 91A, 91B, and 91C."

[0127] The restriction areas 91A, 91B, and 91C correspond to the light receiving areas IA21, IB21, and IC21, respectively. In the detection device 103 of this embodiment, the degree of angular restriction of each of the restriction areas 91A, 91B, and 91C decreases as the restriction areas 91A, 91B, and 91C are farther away from the light emitting elements 60 and 70.

[0128] The second angle limiting filter 91 has a silicon oxide layer 94 and a plurality of light-shielding walls (second light-shielding walls) 95 embedded in the silicon oxide layer 94. In the second angle limiting filter 91, the plurality of light-shielding walls 95 are provided on the light-receiving regions IA21, IB21, and IC21 of the second light-receiving element 161. The plurality of light-shielding walls 95 include light-shielding walls 95a, 95b, 95c, 95d, 95e, 95f, and 95g. Note that the second angle limiting filter 91 can be formed by embedding a plurality of light-shielding walls 95 of different heights in the silicon oxide layer 24 by dividing the wiring formation step of the semiconductor process similar to that of the first angle limiting filter 81 into multiple steps.

[0129] The light-shielding walls 95a and 95b are aligned in the X-axis direction in the first restriction area 91 A. In the present embodiment, the heights of the light-shielding walls 95a and 95b are set to, for example, 4 μm.

[0130] The light-shielding walls 95c and 95d are aligned in the X-axis direction in the second restriction area 91B. In this embodiment, the heights of the light-shielding walls 95c and 95d are set to, for example, 3 μm.

[0131] The light-shielding walls 95e, 95f, and 95g are aligned in the X-axis direction in the third restriction area 91C. In this embodiment, the heights of the light-shielding walls 95e, 95f, and 95g are each set to 2 μm, for example. For example, the distance between adjacent light-shielding walls 95a, 95b, 95c, 95d, 95e, 95f, and 95g in the X-axis direction is set to 3 μm.

[0132] In this embodiment, the degree of angle restriction in each of the restriction areas 91A, 91B, and 91C is determined by the height of the light-shielding walls aligned in the X-axis direction.

[0133] In this embodiment, the height of the light-shielding walls 95c and 95d arranged in the X-axis direction in the second restriction area 91B among the multiple light-shielding walls 95 is lower than the height of the light-shielding walls 95a and 95b arranged in the X-axis direction in the first restriction area 91A among the multiple light-shielding walls 95. Furthermore, the height of the light-shielding walls 95e, 95f, and 95g arranged in the X-axis direction in the third restricted area 91C among the multiple light-shielding walls 95 is lower than the height of the light-shielding walls 95c and 95d arranged in the X-axis direction in the second restricted area 91B among the multiple light-shielding walls 95.

[0134] As shown in FIG. 8, in the second angle limiting filter 91 of this embodiment, by adjusting the height of the light-shielding walls aligned in the X-axis direction as described above, the degree of angle limiting (allowable incident angle) at the second light receiving element 161 decreases as the second light receiving element 161 moves away from the light emitting elements 60, 70 on the +X side.

[0135] In the case of the present embodiment, the degree of angle restriction of the first restriction area 91A in the second angle limiting filter 91 is smaller than the degree of angle restriction of the first restriction area 81A in the first angle limiting filter 81. Specifically, the height of the light-shielding walls 95a, 95b aligned in the X-axis direction in the first restriction area 91A of the second light receiving element 161 is smaller than the height of the light-shielding walls 85a, 85b aligned in the X-axis direction in the first restriction area 81A of the first light receiving element 151.

[0136] That is, the allowable incident angle of the first restriction area 91A in the second angle limiting filter 91 is larger than the allowable incident angle of the first restriction area 81A in the first angle limiting filter 81. By relatively increasing the allowable incident angle of the first restriction area 91A located on the light emitting unit section 11 side (-X side) in the second angle limiting filter 91 in this way, red light LR or near-infrared light LI that is incident on the second light receiving element 161 at a large angle can be incident on the light receiving surface 30a of the sensor 30 without being cut.

[0137] According to the second light receiving element 161 of the present embodiment, since the second angle limiting filter 91 with a smaller angle limiting degree as it is farther from the light emitting elements 60 and 70 in the +X direction is provided, the scattered components LR1 and LI1 that would be cut off by the conventional angle limiting filter can be taken into the sensor 30. Therefore, the second light receiving element 161 can realize high detection accuracy by reducing the variation in the light reception amount in the plane of the light receiving surface 30a of the sensor 30 and efficiently taking in the red light LR or near-infrared light LI emitted from the light emitting unit section 11.

[0138] As described above, according to the detection device 103 of the present embodiment, similar to the detection device 3 of the above embodiment, the detection accuracy of the light receiving unit section 112 can be improved by increasing the S / N ratio and the light reception amount. Therefore, according to the measuring device using the detection device 103 of the present embodiment, a biological measurement device that enables highly accurate detection while suppressing power consumption can be provided.

[0139] (Example) In order to demonstrate the effects of the detection devices 3 and 103 of the above embodiments, the present inventors performed simulations on the light reception amount according to the distance from the light emitting unit section in the light receiving element and the light reception amount ratio for the following Example 1, Example 2, and Comparative Example.

[0140] Specifically, the detection device 3 of the first embodiment was taken as Example 1, the detection device 103 of the second embodiment was taken as Example 2, and a detection device using an angle limiting filter in which light shielding walls were embedded at equal intervals was taken as the Comparative Example. In the angle limiting filter of the detection device of the Comparative Example, for example, the intervals between adjacent light shielding walls were each set to 3 μm, and the heights of each light shielding wall were each set to 5 μm.

[0141] For the detection devices of Example 1, Example 2, and the Comparative Example, the results of simulating the amount of light received by the light-receiving element according to the distance from the light-emitting unit are shown in the graph of FIG. 9. In FIG. 9, the horizontal axis of the graph indicates the distance from the light-emitting unit in the direction in which the light-emitting unit and the light-receiving unit are arranged (for example, the X-axis direction in FIG. 5), and the vertical axis of the graph indicates the amount of light received by the light-receiving element.

[0142] As shown in FIG. 9, it was confirmed that for the detection device of the Comparative Example, in the detection devices of Example 1 and Example 2, the amount of light received by the light-receiving element increases as the distance from the light unit increases. That is, it was confirmed that the detection devices of Example 1 and Example 2 can equalize the amount of light received within the plane of the light-receiving element by reducing the degree of angle limitation of the angle-limiting filter as the distance from the light unit increases.

[0143] In addition, for the detection devices of Example 1, Example 2, and the Comparative Example, the results of simulating the light-receiving ratio of the light-receiving element are shown in the graph of FIG. 10. In FIG. 10, each amount of light received by the detection devices of Example 1 and Example 2 is shown when the amount of light received by the light-receiving element in the detection device of the Comparative Example is set to 1.0.

[0144] As shown in FIG. 10, it was confirmed that for the detection device of the Comparative Example, the detection devices of Example 1 and Example 2 can increase the amount of light received by the light-receiving element to 1.36 or 1.27.

[0145] From the results shown in FIGS. 9 and 10, it was confirmed that the detection device of Example 1 has a higher effect of increasing the amount of light received by the light-receiving element than the detection device of Example 2. As described above, according to the detection devices 3 and 103 of the above-described embodiment, it was demonstrated that the amount of light received by each light-receiving element can be increased compared to the detection device of the Comparative Example.

[0146] Although the present invention has been described based on the above-described embodiment, the present invention is not limited to the above-described embodiment, and can be implemented in various aspects without departing from the gist thereof. For example, in the above embodiment, a human being is exemplified as the living body, but the present invention is also applicable to the measurement of biological information (for example, pulse) of other animals.

[0147] Also, in the measuring device 100 of the first embodiment, the case where the detection device 3 is provided in the main body 1 is taken as an example, but the installation location of the detection device 3 is not limited to this. For example, it may be embedded on the back side of the belt.

[0148] Also, as the measuring device 100 of the first embodiment, a wristwatch type configuration is taken as an example. However, for example, the present invention is also applicable to a configuration that is worn around the neck of the subject as a necklace type, a configuration that is attached to the body of the subject as a sticker type, or a configuration that is worn on the head of the subject as a head-mounted display type.

[0149] Also, in the detection device 3 of the first embodiment, the case where the sensor 20 of the first light receiving element 51 includes four light receiving areas is taken as an example, but the number of light receiving areas is not limited to this. For example, the light receiving area may be composed of at least two (the first light receiving area IA1 and the second light receiving area IB1), or may be composed of five or more. Note that the same applies to the sensor 30 of the second light receiving element 61, and it may be composed of at least two light receiving areas (the first light receiving area IA2 and the second light receiving area IB2), or may be composed of five or more light receiving areas.

[0150] Also, in the detection device 103 of the second embodiment, the case where the sensor 30 of the first light receiving element 151 includes three light receiving areas is taken as an example, but the sensor 20 of the first light receiving element 151 may be composed of at least two light receiving areas (the first light receiving area IA11 and the second light receiving area IB11), or may be composed of five or more light receiving areas. Also, the same applies to the sensor 30 of the second light receiving element 161, and it may be composed of at least two light receiving areas (the first light receiving area IA21 and the second light receiving area IB21), or may be composed of five or more light receiving areas.

[0151] In the detection device 3 of the first embodiment, although the case where each of the light-emitting elements 50, 60, and 70 emits light in a time-division manner has been taken as an example, since the first light-receiving element 51 corresponding to the green light LG of the first light-emitting element 50 is provided individually, the first light-emitting element 50 may be constantly lit instead of in a time-division manner. Note that, similarly in the second embodiment, the first light-emitting element 50 may be constantly lit instead of in a time-division manner.

[0152] The detection device according to one aspect of the present invention may have the following configuration. The detection device according to one aspect of the present invention includes a light-emitting unit that emits light, and a light-receiving unit that has an angle-limiting member that limits the incident angle of the light from the light-emitting unit. The light-receiving unit includes a first light-receiving region and a second light-receiving region that is separated from the light-emitting unit more than the first light-receiving region. The angle-limiting member includes a first limiting region corresponding to the first light-receiving region and a second limiting region corresponding to the second light-receiving region. The degree of angle limitation in the second limiting region is smaller than the degree of angle limitation in the first limiting region.

[0153] In the detection device according to one aspect of the present invention, when the direction in which the light-emitting unit and the light-receiving unit are arranged is defined as the first direction, the angle-limiting member has a plurality of light-shielding walls provided in the light-receiving unit, and the interval between the walls adjacent to each other in the first direction in the second limiting region among the plurality of light-shielding walls may be configured to be larger than the interval between the walls adjacent to each other in the first direction in the first limiting region among the plurality of light-shielding walls.

[0154] In the detection device according to one aspect of the present invention, the light-emitting unit includes a first light-emitting element that emits first light having a green wavelength band, and a second light-emitting element that is provided in a second direction intersecting the first direction with respect to the first light-emitting element and emits second light having a wavelength band longer than the green wavelength band. The light-receiving unit includes a first light-receiving element that receives the first light from the first light-emitting element and a second light-receiving element that receives the second light from the second light-emitting element. In the first direction, the first light-receiving element may be provided closer to the light-emitting unit than the second light-receiving element.

[0155] In one embodiment of the detection device of the present invention, the angle limiting member includes a first angle limiting filter that limits the angle of incidence of the first light to the first light receiving element, and a second angle limiting filter that limits the angle of incidence of the second light to the second light receiving element, and the degree of angle limiting of the first limiting region in the second angle limiting filter may be smaller than the degree of angle limiting of the first limiting region in the first angle limiting filter.

[0156] In one embodiment of the detection device of the present invention, the first angle limiting filter has a plurality of first light-shielding walls provided on the first light-receiving element, and the second angle limiting filter has a plurality of second light-shielding walls provided on the second light-receiving element, and the distance between adjacent second light-shielding walls in the first direction in the first restriction area of the second light-receiving element may be larger than the distance between adjacent first light-shielding walls in the first direction in the first restriction area of the first light-receiving element.

[0157] In one embodiment of the detection device of the present invention, when the direction in which the light-emitting unit and the light-receiving unit are arranged is defined as a first direction, the angle limiting member may have a plurality of light-shielding walls provided in the light-receiving unit, and the height of the light-shielding walls arranged in the first direction in the second restriction area may be lower than the height of the light-shielding walls arranged in the first direction in the first restriction area.

[0158] In one embodiment of the detection device of the present invention, the light-emitting unit includes a first light-emitting element that emits first light having a green wavelength band, and a second light-emitting element that is arranged in a second direction that intersects the first direction with respect to the first light-emitting element and emits second light having a wavelength band longer than the green wavelength band, and the light-receiving unit includes a first light-receiving element that receives the first light from the first light-emitting element, and a second light-receiving element that receives the second light from the second light-emitting element, and in the first direction, the first light-receiving element may be arranged closer to the light-emitting unit than the second light-receiving element.

[0159] In one embodiment of the detection device of the present invention, the angle limiting member includes a first angle limiting filter that limits the angle of incidence of the first light to the first light receiving element, and a second angle limiting filter that limits the angle of incidence of the second light to the second light receiving element, and the degree of angle limiting of the first limiting region in the second angle limiting filter may be smaller than the degree of angle limiting of the first limiting region in the first angle limiting filter.

[0160] In one embodiment of the detection device of the present invention, the first angle limiting filter has a plurality of first light-shielding walls provided on the first light-receiving element, and the second angle limiting filter has a plurality of second light-shielding walls provided on the second light-receiving element, and the height of the second light-shielding walls lined up in the first direction in the first restriction area of the second light-receiving element may be lower than the height of the first light-shielding walls lined up in the first direction in the first restriction area of the first light-receiving element.

[0161] In one embodiment of the detection device of the present invention, the light receiving unit may further include a third light receiving region that is farther away from the light emitting unit than the second light receiving region, and the angle limiting member may further include a third restriction region that corresponds to the third light receiving region and has a smaller degree of angle restriction than the second restriction region.

[0162] The detection device according to one aspect of the present invention may have the following configuration. A detection device according to one embodiment of the present invention comprises a light-emitting unit that emits light onto a living body, a light-receiving unit that is aligned in a first direction relative to the light-emitting unit and receives light from the living body, and a plurality of light-shielding walls that are aligned in the first direction and limit the angle of incidence of light onto the light-receiving unit, wherein the spacing between the light-shielding walls in an area far from the light-emitting unit is greater than the spacing between the light-shielding walls in an area close to the light-emitting unit.

[0163] The measurement device according to one aspect of the present invention may have the following configuration. A measurement device according to one aspect of the present invention includes the detection device according to the above aspect, and an information analysis unit that identifies biological information from a detection signal that indicates a detection result by the detection device. [Explanation of symbols]

[0164] 3,103...detection device, 5...control device (information analysis section), 11...light-emitting unit section (light-emitting section), 12...light-receiving unit section (light-receiving section), 21,81...first angle-limiting filter (angle-limiting member), 25,85...light-shielding wall (first light-shielding wall), 31,91...second angle-limiting filter (angle-limiting member), 35,95...light-shielding wall (second light-shielding wall), 50...first light-emitting element, 51,151...first light-receiving element, 60 ...second light-emitting element, 61, 161...second light-receiving element, 100...measuring device, 21A, 31A, 81A, 91A...first restriction area, 21B, 31B, 81B, 91B...second restriction area, IA1, IA11, IA2, IA21...first light-receiving area, IB1, IB11, IB2, IB21...second light-receiving area, LG...green light (first light), LR...red light (second light), M...measurement site (living body), S...detection signal.

Claims

1. A light-emitting unit that emits light, and a light-receiving unit having an angle-limiting member that limits the incident angle of light from the light-emitting unit, wherein the light-receiving unit includes a first light-receiving region and a second light-receiving region that is farther from the light-emitting unit than the first light-receiving region, the angle-limiting member includes a first limiting region corresponding to the first light-receiving region and a second limiting region corresponding to the second light-receiving region, the degree of angle limitation in the second limiting region is smaller than the degree of angle limitation in the first limiting region, when the direction in which the light-emitting unit and the light-receiving unit are arranged is defined as a first direction, the angle-limiting member has a plurality of light-shielding walls provided on the light-receiving unit, the distance between adjacent walls in the first direction in the second limiting region among the plurality of light-shielding walls is larger than the distance between adjacent walls in the first direction in the first limiting region among the plurality of light-shielding walls, the light-emitting unit includes a first light-emitting element that emits first light having a green wavelength band, and a second light-emitting element that is provided in a second direction intersecting the first direction with respect to the first light-emitting element and emits second light having a wavelength band longer than the green wavelength band, the light-receiving unit includes a first light-receiving element that receives the first light from the first light-emitting element and a second light-receiving element that receives the second light from the second light-emitting element, in the first direction, the first light-receiving element is provided closer to the light-emitting unit than the second light-receiving element, the angle-limiting member includes a first angle-limiting filter that limits the incident angle of the first light with respect to the first light-receiving element and a second angle-limiting filter that limits the incident angle of the second light with respect to the second light-receiving element, the degree of angle limitation of the first limiting region in the second angle-limiting filter is smaller than the degree of angle limitation of the first limiting region in the first angle-limiting filter, A detection device.

2. The first angle-limiting filter has a plurality of first light-shielding walls provided on the first light-receiving element, the second angle-limiting filter has a plurality of second light-shielding walls provided on the second light-receiving element, the distance between adjacent second light-shielding walls in the first direction in the first limiting region of the second light-receiving element is larger than the distance between adjacent first light-shielding walls in the first direction in the first limiting region of the first light-receiving element, The detection device according to Claim 1.

3. A light-emitting unit that emits light, and A light receiving unit having an angle limiting member that limits the incident angle of light from the light emitting unit, The light receiving unit includes a first light receiving region and a second light receiving region that is separated from the light emitting unit more than the first light receiving region, The angle limiting member includes a first limiting region corresponding to the first light receiving region and a second limiting region corresponding to the second light receiving region, The degree of angle limitation in the second limiting region is smaller than the degree of angle limitation in the first limiting region, When the direction in which the light emitting unit and the light receiving unit are arranged is defined as the first direction, The angle limiting member has a plurality of light shielding walls provided on the light receiving unit, The height of the light shielding walls arranged in the first direction in the second limiting region is lower than the height of the light shielding walls arranged in the first direction in the first limiting region, The light emitting unit includes a first light emitting element that emits first light having a green wavelength band, and a second light emitting element that is provided in a second direction intersecting the first direction with respect to the first light emitting element and emits second light having a wavelength band longer than the green wavelength band, The light receiving unit includes a first light receiving element that receives the first light from the first light emitting element and a second light receiving element that receives the second light from the second light emitting element, In the first direction, the first light receiving element is provided closer to the light emitting unit than the second light receiving element, The angle limiting member includes a first angle limiting filter that limits the incident angle of the first light with respect to the first light receiving element and a second angle limiting filter that limits the incident angle of the second light with respect to the second light receiving element, The degree of angle limitation of the first limiting region in the second angle limiting filter is smaller than the degree of angle limitation of the first limiting region in the first angle limiting filter, Detection device.

4. The first angle limiting filter has a plurality of first light shielding walls provided on the first light receiving element, The second angle limiting filter has a plurality of second light shielding walls provided on the second light receiving element, The height of the second light shielding walls arranged in the first direction in the first limiting region of the second light receiving element is lower than the height of the first light shielding walls arranged in the first direction in the first limiting region of the first light receiving element, The detection device according to claim 3.

5. The light receiving unit further includes a third light receiving region that is separated from the light emitting unit more than the second light receiving region, The angle limiting member corresponds to the third light receiving region and further includes a third limiting region having a smaller angle limiting degree than the second limiting region. The detection device according to any one of claims 1 to 4.

6. The detection device according to any one of claims 1 to 5, and an information analysis unit that specifies biological information from a detection signal indicating a detection result by the detection device. Measuring device.

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