Detection device

Abstract

Provided is a detection device in which the component-mounting areas for a light source and a photodiode can be reduced to improve the utilization efficiency of light. The detection device is provided with: a substrate; a light source for irradiating an object to be detected with light; and an organic photodiode in which a lower electrode, a lower buffer layer, an active layer, an upper buffer layer and an upper electrode are laminated in this order. The organic photodiode is provided on the substrate, the surface of the substrate is exposed through an opening provided so as to penetrate through the organic photodiode, and the light source is provided on the substrate in the opening.

Description

Detection device

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

[0002] Optical sensors capable of measuring fingertip pulse waves are known (see, for example, Patent Document 1). In such optical sensors, light emitted from a light-emitting unit (light source) is scattered and reflected by the object to be detected, and then enters a light-receiving unit (photodiode). In this way, the light-receiving unit detects biological information from the object to be detected.

[0003] JP 2015-33820 A

[0004] In the optical sensor described in Patent Document 1, the light source and photodiode are mounted on the same light-transmitting member and arranged in a horizontal row. This increases the mounting area of ​​the components, posing a challenge to miniaturizing the entire device. Furthermore, when light is irradiated onto the photodiode, the amount of light that the photodiode can absorb is limited, which may reduce the light utilization efficiency.

[0005] An object of the present invention is to provide a detection device that can reduce the area where components such as a light source and a photodiode are mounted, thereby improving the efficiency of light utilization.

[0006] A detection device according to one embodiment of the present invention comprises a substrate, a light source for irradiating a detected object with light, and an organic photodiode having a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode stacked in this order, wherein the organic photodiode is provided on the substrate, an opening extending through the organic photodiode exposes the surface of the substrate, and the light source is provided on the substrate at the opening.

[0007] FIG. 1 is a schematic diagram showing an example of the external appearance of a detection device according to embodiment 1, when a finger is placed inside the detection device, as viewed from the side of the housing. FIG. 2 is a schematic cross-sectional view taken along the line II-II' in FIG. 1. FIG. 3 is a schematic cross-sectional view showing an example of the configuration of an optical sensor and a light source of the detection device shown in FIG. 2. FIG. 4 is a plan view showing the bottom layer of a substrate according to the first embodiment. FIG. 5 is a schematic cross-sectional view taken along the line V-V' in FIG. 3. FIG. 6 is a schematic cross-sectional view taken along the line VI-VI' in FIG. 3. FIG. 7 is a circuit diagram showing an example of the configuration of a detection device according to embodiment 1. FIG. 8 is a flowchart showing an example of processing related to output of blood oxygen saturation in embodiment 1. FIG. 9 is a timing waveform diagram showing an example of operation of the first light source and the second light source of the detection circuit according to embodiment 1. FIG. 10 is a plan view showing pulse wave detection ranges of the first light source and the second light source of the detection device according to embodiment 1. FIG. 11 is a circuit diagram showing an example of the configuration of a detection device according to embodiment 1. FIG. 12 is a flowchart showing an example of the processing flow related to output of a heart rate in embodiment 1. Fig. 13 is a timing waveform diagram showing an example of operation of the third light source of the detection circuit according to embodiment 1. Fig. 14 is a plan view showing a pulse wave detection range of the third light source of the detection device according to embodiment 1. Fig. 15 is a plan view showing a pulse wave detection range of the third light source of a detection device according to a comparative example.

[0008] Modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate. Note that the disclosure is merely an example, and any appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the present disclosure are naturally included within the scope of the present disclosure. Furthermore, for clarity of explanation, the drawings may schematically depict the width, thickness, shape, etc. of each part compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this disclosure and each figure, elements similar to those described above with reference to the previous figures may be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0009] In this specification and claims, when expressing an aspect of placing another structure on top of a certain structure, the term "on top" is used, unless otherwise specified, to include both a case in which another structure is placed directly on top of a certain structure so as to be in contact with the certain structure, and a case in which another structure is placed above a certain structure via yet another structure.

[0010] (Embodiment 1) Fig. 1 is a schematic diagram showing an example of the appearance of a detection device according to embodiment 1 when a finger is placed inside the detection device, as viewed from the side of the housing. Fig. 2 is a schematic cross-sectional view taken along line II-II' in Fig. 1. Fig. 3 is a schematic diagram showing an example configuration of an optical sensor and a light source of the detection device shown in Fig. 1. Fig. 4 is a plan view showing a substrate according to embodiment 1. Fig. 5 is a schematic cross-sectional view taken along line V-V' in Fig. 3. Fig. 6 is a schematic cross-sectional view taken along line VI-VI' in Fig. 3. Note that Fig. 2 shows only the basic configuration of the detection device according to embodiment 1, and omits other configurations.

[0011] The detection device 100 shown in FIG. 1 is a ring-shaped device that can be attached to or detached from the human body, and is worn on a detection target Fg on the human body. The detection target Fg is a finger, and may be any of the thumb, index finger, middle finger, ring finger, little finger, etc. The human body is an individual to be authenticated, whose identity is verified by the detection device 1. The detection device 1 can detect biometric information about a living organism from the detection target Fg attached to it. The detection target Fg is an example of a measurement target. The measurement target is a living organism or part of a living organism, and is a measurement target. The detection device 1 is made into a ring or wristband, making it easy for the user to carry. In the following description, it is assumed that the detection device 100 is used as a ring.

[0012] 2, the detection device 100 includes a housing 200, a substrate 21, a first light source 61, a second light source 62, third light sources 63 and 64, and an optical sensor PD. The optical sensor PD includes a first optical sensor PD1, a second optical sensor PD2, and a third optical sensor PD3. The detection device 100 includes a battery (not shown) inside the housing 200 and is a device that operates on battery power.

[0013] As shown in FIGS. 3 and 5 , the optical sensor PD is provided on a substrate 21. An opening OP penetrating the optical sensor PD exposes the surface of the substrate 21. As shown in FIG. 3 , each of the first optical sensor PD1, the second optical sensor PD2, and the third optical sensor PD3 includes a plurality of lower electrodes 11 arranged side by side along the circumferential direction 200C. The openings OP are provided so as to penetrate each of the lower electrodes 11. The openings OP include a first opening OP1, a second opening OP2, and a third opening OP3. The first light source 61, the second light source 62, and the third light sources 63 and 64 are each provided on the substrate 21. In the circumferential direction 200C along the first direction Dx, the first opening OP1 is provided with the first light source 61 and the second light source 62. The second opening OP2 and the third opening OP3 are provided with the third light sources 63 and 64, respectively. The first opening OP1 is provided between the second opening OP2 and the third opening OP3. The first light source 61, the second light source 62, and the third light sources 63 and 64 are each surrounded by the lower electrode 11.

[0014] As shown in FIGS. 1 and 2 , the housing 200 is formed in a ring shape (annular shape) that can be attached to the subject Fg and is a mounting member that is attached to a living body. In the example shown in FIG. 2 , the housing 200 includes a first housing 210 and a second housing 220. The first housing 210 and the second housing 220 are integrally formed into a ring shape. The first housing 210 is a member that comes into contact with the human body on which the housing 200 is attached. The first housing 210 houses a first light source 61, a second light source 62, a third light source 63, 64, an optical sensor PD, etc. The first housing 210 is formed in a ring shape using a housing material such as a transparent synthetic resin or silicone. The second housing 220 has a surface of the housing 200 that covers the outer peripheral surface 210A of the first housing 210. The second housing 220 is formed in a ring shape using a material such as a metal or a non-transparent synthetic resin. The housing 200 accommodates the substrate 21, on which the first light source 61, the second light source 62, the third light sources 63 and 64, the optical sensor PD, etc. are mounted, inside the first housing 210. The substrate 21 is accommodated inside the housing 200 by, for example, forming the housing 200 in a ring shape in a mold and filling the surrounding area with a filling material.

[0015] As shown in FIG. 3 , the substrate 21 is formed in a deformable band shape. The substrate 21 is a base material formed by laminating two layers together. The substrate 21 is an insulating substrate, such as a light-transmitting flexible printed circuit (FPC). A first light source 61, a second light source 62, and third light sources 63 and 64 are mounted on the surface of the top layer of the substrate 21. The substrate 21 electrically connects the first light source 61, the second light source 62, the third light source 63 and 64, the optical sensor PD, and the control circuit 122.

[0016] In the following description, the first direction Dx is a direction in a plane parallel to the substrate 21. The second direction Dy is a direction in a plane parallel to the substrate 21, and is a direction perpendicular to the first direction Dx. The second direction Dy may intersect the first direction Dx without being perpendicular to it. The third direction Dz is a direction perpendicular to the first direction Dx and the second direction Dy. The third direction Dz is the normal direction of the substrate 21. Furthermore, "planar view" refers to the positional relationship when viewed from a direction perpendicular to the substrate 21.

[0017] 2 , the substrate 21 is housed inside the housing 200 so that the surface on which the optical sensor PD, the first light source 61, the second light source 62, and the third light sources 63 and 64 are mounted faces the inner circumferential surface 210B of the housing 200. Note that if the substrate 21 is translucent, the optical sensor PD, the first light source 61, the second light source 62, and the third light sources 63 and 64 may be mounted on the back surface opposite the front surface. In this case, the first light source 61, the second light source 62, and the third light sources 63 and 64 may be arranged so that they emit light toward the substrate 21 and the light that has passed through the substrate 21 is emitted to the outside from the inner circumferential surface 210B side of the housing 200.

[0018] As shown in FIG. 2 , the first light source 61, the second light source 62, and the third light sources 63, 64 are provided inside the housing 200 and are configured to irradiate light toward the detection object Fg attached to the ring-shaped housing 200. The first light source 61, the second light source 62, and the third light sources 63, 64 are, for example, inorganic light-emitting diodes (LEDs) or organic light-emitting diodes (OLEDs). The first light source 61, the second light source 62, and the third light sources 63, 64 irradiate light of a predetermined wavelength. In this embodiment, the first light source 61 has multiple light sources capable of irradiating red light. The second light source 62 has multiple light sources capable of irradiating infrared light. The third light sources 63, 64 have multiple light sources capable of irradiating green light.

[0019] 2 and 3 , light emitted from the first light source 61 and the second light source 62 and reflected by the detection object Fg is incident on the first optical sensor PD1. Light emitted from the third light source 63 and reflected by the surface of the detection object Fg is incident on the second optical sensor PD2. Light emitted from the third light source 64 and reflected by the surface of the detection object Fg is incident on the third optical sensor PD3. This allows the detection device 100 to detect information about the living body inside the detection object Fg. Examples of information about the living body include pulse waves and pulse rates of the fingers and palms. That is, the detection device 100 may be configured as a vein detection device that detects biological information such as veins.

[0020] The optical sensor PD is provided inside the first housing 210 of the housing 200 and is a sensor capable of detecting light incident from the irradiation sides of the first light source 61, the second light source 62, and the third light sources 63 and 64. The irradiation sides of the first light source 61, the second light source 62, and the third light sources 63 and 64 are inside the ring-shaped housing 200 and are the sides that irradiate the detection target Fg to which the housing 200 is attached. The optical sensor PD is an organic photodiode (OPD). The optical sensor PD is attached to the substrate 21 and is provided inside the housing 200 so as to be aligned with the first light source 61, the second light source 62, and the third light sources 63 and 64 in the circumferential direction 200C of the housing 200 (first direction Dx).

[0021] The first optical sensor PD1, the second optical sensor PD2, and the third optical sensor PD3 are electrically connected to the uppermost layer of the substrate 21. The first optical sensor PD1, the second optical sensor PD2, and the third optical sensor PD3 are configured by stacking a lower electrode 11 and one upper electrode 15. The upper electrode 15 covers the three lower electrodes 11 in a plan view.

[0022] 3 , one ends of the first wirings Rx1, Rx2, and Rx3 provided on the surface of the top layer of the substrate 21 are connected to the detection circuit 48 of the control circuit 122 via a plurality of signal lines SL. The other ends of the first wirings Rx1, Rx2, and Rx3 are electrically connected to the lower electrode 11. The first wirings Rx1, Rx2, and Rx3 are formed, for example, from metal wiring, and are formed from a material having better conductivity than the lower electrode 11 of the photosensor PD. The first wirings Rx1, Rx2, and Rx3 are formed, for example, from a transparent conductive material such as ITO (Indium Tin Oxide).

[0023] 3 and 6 , the detection device 100 has a power supply electrode 211 extending in the second direction Dy. The power supply electrode 211 is electrically connected to a connection portion 212 via a conductive material 213, and a sensor power supply signal is supplied from the power supply circuit 123 via the connection portion 212. The upper electrode 15 is electrically connected to the power supply electrode 211 by the conductive material 213. The conductive material 213 is provided on the substrate 21 so as to straddle the upper electrode 15 and the power supply electrode 211, and is made of a conductive material. As a result, the upper electrode 15 is supplied with a sensor power supply signal from the power supply circuit 123 via the power supply electrode 211.

[0024] The second wiring 260 is electrically connected to the power supply electrode 211 by a conductive material 213. The second wiring 260 is formed, for example, of a metal wiring and is formed of a material having conductivity. The second wiring 260 is formed of a material having better conductivity than the upper electrode 15. The second wiring 260 is provided in a layer between the uppermost layer side of the substrate 21 and the photosensor PD in the third direction Dz. The second wiring 260 is electrically connected to the upper electrode 15 and the connection portion 212. The second wiring 260 is connected to the control circuit 122 via a wiring 261 that supplies a power supply voltage to the second wiring 260.

[0025] The control circuit 122 is a circuit that supplies control signals to the optical sensors PD to control the detection operation. Each of the optical sensors PD outputs an electrical signal corresponding to the light irradiated thereon as a detection signal to the detection circuit 48.

[0026] As shown in FIG. 4 , the bottom layer of the substrate 21 has an anode connection wiring 23 and a cathode connection wiring 24. The bottom layer of the substrate 21 also has through-holes TH1 and TH2 that penetrate in the third direction Dz. One end of the anode connection wiring 23 is connected to the anode sides of the first light source 61, the second light source 62, and the third light sources 63 and 64 via the through-hole TH1. One end of the cathode connection wiring 24 is connected to the cathode sides of the first light source 61, the second light source 62, and the third light sources 63 and 64 via the through-hole TH2. The other ends of the anode connection wiring 23 and the cathode connection wiring 24 are connected to the control circuit 122. The first light source 61, the second light source 62, and the third light sources 63 and 64 are switched between an lit state and an unlit state based on a control signal from the control circuit 122.

[0027] 3 and 5 , the detection device 100 further includes a first light-shielding wall 55 and a second light-shielding wall 56. The first light-shielding wall 55 is disposed at each of the first opening OP1, the second opening OP2, and the third opening OP3. The first light-shielding wall 55 is disposed to surround the first light source 61, the second light source 62, and the third light sources 63 and 64, respectively, and blocks light incident on the first light source 61, the second light source 62, and the third light sources 63 and 64. The first light-shielding wall 55 protrudes higher in the third direction Dz than the first light source 61, the second light source 62, and the third light sources 63 and 64.

[0028] The second light-shielding wall 56 is disposed on the outer periphery of the optical sensor PD. The second light-shielding wall 56 blocks light incident on the optical sensor PD. The second light-shielding wall 56 protrudes higher than the optical sensor PD in the third direction Dz. The first light-shielding wall 55 and the second light-shielding wall 56 are formed of black resin or a metal material such as aluminum. The first light-shielding wall 55 can prevent light emitted from the first light source 61, the second light source 62, and the third light sources 63 and 64 from directly entering the optical sensor PD. Furthermore, the second light-shielding wall 56 can prevent external light from entering the optical sensor PD.

[0029] 5, the detection device 100 further includes a protective member 80 and a protrusion 81. The protective member 80 and the protrusion 81 are made of a light-transmitting resin.

[0030] The protrusion 81 protrudes in the third direction Dz. The first light source 61 and the second light source 62 are covered by the protrusion 81. This makes it easier for the protrusion 81 to be pressed toward the object to be detected Fg when it comes into contact with the object to be detected Fg, making it easier for light to be incident on the object to be detected Fg.

[0031] Furthermore, the protective member 80 is provided in contact with the first light-shielding wall 55 and the second light-shielding wall 56 in the third direction Dz. The optical sensor PD, the first light source 61, the second light source 62, and the third light sources 63, 64 are covered by the protective member 80. This prevents the detection object Fg from coming into contact with the optical sensor PD, the first light source 61, the second light source 62, and the third light sources 63, 64. The protective member 80 may be formed integrally with the protrusion 81.

[0032] As shown in FIG. 6, the detection device 100 includes a substrate 21, an insulating layer 27, and a photosensor PD.

[0033] The insulating layer 27 is provided on the uppermost layer of the substrate 21. The insulating layer 27 is disposed between the substrate 21 and the photosensor PD. The insulating layer 27 may be an inorganic insulating film or an organic insulating film.

[0034] The photosensor PD is provided on the insulating layer 27. The photosensor PD has a lower electrode 11, a lower buffer layer 12, an active layer 13, an upper buffer layer 14, and an upper electrode 15. In the photosensor PD, the lower electrode 11, the lower buffer layer 12 (hole transport layer), the active layer 13, the upper buffer layer 14 (electron transport layer), and the upper electrode 15 are stacked in this order in a third direction Dz perpendicular to the substrate 21.

[0035] The lower electrode 11 is an anode electrode of the photosensor PD and is formed of a transparent conductive material such as indium tin oxide (ITO). The active layer 13 changes its characteristics (e.g., voltage-current characteristics and resistance value) depending on the light irradiated thereon. An organic material is used as the material for the active layer 13. Specifically, the active layer 13 has a bulk heterostructure in which a p-type organic semiconductor and an n-type fullerene derivative (PCBM), which is an n-type organic semiconductor, are mixed. The active layer 13 may be made of, for example, a low molecular weight organic material such as C60 (fullerene), PCBM (phenyl C61-butyric acid methyl ester), CuPc (copper phthalocyanine), F16CuPc (fluorinated copper phthalocyanine), rubrene (5,6,11,12-tetraphenyltetracene), or PDI (a perylene derivative).

[0036] The active layer 13 can be formed using these low-molecular-weight organic materials by a vapor deposition (dry process). In this case, the active layer 13 may be, for example, a laminated film of CuPc and F16CuPc, or a laminated film of rubrene and C60. The active layer 13 can also be formed by a coating (wet process). In this case, the active layer 13 is made of a material that combines the above-mentioned low-molecular-weight organic material with a high-molecular-weight organic material. Examples of high-molecular-weight organic materials that can be used include P3HT (poly(3-hexylthiophene)) and F8BT (F8-alt-benzothiadiazole). The active layer 13 can be a film in which P3HT and PCBM are mixed, or a film in which F8BT and PDI are mixed.

[0037] The lower buffer layer 12 is a hole transport layer. The upper buffer layer 14 is an electron transport layer. The lower buffer layer 12 and the upper buffer layer 14 are provided to facilitate the holes and electrons generated in the active layer 13 reaching the lower electrode 11 or the upper electrode 15. The lower buffer layer 12 (hole transport layer) is directly in contact with the lower electrode 11 and is also provided in the region between adjacent lower electrodes 11. The active layer 13 is directly in contact with the lower buffer layer 12. The material of the hole transport layer is a metal oxide layer. Tungsten oxide (WO3), molybdenum oxide, etc. are used as the metal oxide layer.

[0038] The upper buffer layer 14 (electron transport layer) is in direct contact with the active layer 13, and the upper electrode 15 is in direct contact with the upper buffer layer 14. Ethoxylated polyethyleneimine (PEIE) is used as the material for the electron transport layer.

[0039] The materials and manufacturing methods of the lower buffer layer 12, the active layer 13, and the upper buffer layer 14 are merely examples, and other materials and manufacturing methods may be used. For example, the lower buffer layer 12 and the upper buffer layer 14 are not limited to single-layer films, and may be formed as multilayer films including an electron blocking layer and a hole blocking layer.

[0040] The upper electrode 15 is provided on the upper buffer layer 14. The upper electrode 15 is a cathode electrode of the photosensor PD and is formed continuously over the entire photosensor PD. In other words, the upper electrode 15 is provided continuously over the multiple photosensors PD. The upper electrode 15 faces the multiple lower electrodes 11, with the lower buffer layer 12, the active layer 13, and the upper buffer layer 14 sandwiched between them. The upper electrode 15 is formed of a light-transmitting conductive material such as ITO or IZO. A portion of the end of the upper surface of the upper electrode 15 is electrically connected to the conductive material 213.

[0041] [Operation Example 1 of the Detection Device] Next, the detection device 100 measures the oxygen saturation in the blood (hereinafter referred to as the blood oxygen saturation (SpO ２) will be described. FIG. 7 is a circuit diagram showing an example of the configuration of the detection device according to the first embodiment. FIG. 8 is a flowchart showing an example of processing related to output of blood oxygen saturation in the first embodiment. FIG. 9 is a timing waveform diagram showing an example of operation of the first light source and the second light source of the detection circuit according to the first embodiment. FIG. 10 is a plan view showing the pulse wave detection range of the first light source and the second light source of the detection device according to the first embodiment.

[0042] As shown in FIG. 7, the detection circuit 48 includes switch circuits SSW1, SSW2, and SSW3, a reset transistor RST, and an A / D conversion circuit 43.

[0043] The first wirings Rx1, Rx2, and Rx3 are connected to a detection circuit 48. The detection circuit 48 is electrically connected to the lower electrode 11. The detection circuit 48 may be formed as a circuit separate from the control circuit 122.

[0044] A storage capacitor Cs is formed between the anode side of each of the first optical sensor PD1, the second optical sensor PD2, and the third optical sensor PD3 and the first wiring Rx1, Rx2, and Rx3.

[0045] The anode side of the photosensor PD is connected to GND. The switch circuits SSW1, SSW2, and SSW3 are connected to the cathode side of the photosensor PD via first wirings Rx1, Rx2, and Rx3.

[0046] One of the source and drain of the reset transistor RST is connected to one of the switch circuits SSW1, SSW2, SSW3 and the A / D conversion circuit 43. The other of the source and drain of the reset transistor RST is connected to GND. When the reset transistor RST is turned on (conductive), the cathode potential of the photosensor PD is reset, and the sensor signal is reset.

[0047] Although the reset transistor RST has a single gate structure, the reset transistor RST may have a so-called double gate structure in which two transistors are connected in series, or may have a structure in which three or more transistors are connected in series.

[0048] The A / D conversion circuit 43 converts the analog signal output by the first optical sensor PD1 into a digital signal. An external control device processes the digital signal from the A / D conversion circuit 43.

[0049] In the first operational example of the detection device 100, the switch circuit SSW1 is in an on state (see FIG. 7). The reset transistor RST is in an on state, and the sensor signal is reset (see FIG. 9).

[0050] 8, the first light source 61 is turned on to irradiate the detection object Fg with red light (step ST101). In step ST101, the reset transistor RST is in an off state (see FIG. 9).

[0051] Next, the red light IL1 (see FIG. 10) reflected by the object Fg is irradiated onto the first optical sensor PD1, and the first optical sensor PD1 is read out (step ST102, see FIG. 9).

[0052] Next, the first light source 61 is turned off, and the red light IL1 stops irradiating the first optical sensor PD1 (step ST103).In step ST103, the reset transistor RST is in the on state (see FIG. 9).

[0053] Next, the second light source 62 is turned on to irradiate the detection object Fg with infrared light (step ST104). In step ST104, the reset transistor RST is in the OFF state (see FIG. 9).

[0054] Next, the infrared light IL2 (see FIG. 10) reflected by the object Fg is irradiated onto the first optical sensor PD1, and the first optical sensor PD1 is read out (step ST105, see FIG. 9).

[0055] Next, the second light source 62 is turned off, and the irradiation of the infrared light IL2 onto the first optical sensor PD1 is stopped (step ST106).In step ST106, the reset transistor RST is in the on state (see FIG. 9).

[0056] The first light source 61 and the second light source 62 are statically lit (DC lit) during the period when they are lit, and light is constantly irradiated onto the detection object Fg. In the processing up to step ST106, the first light source 61 and the second light source 62 are lit during the period when the third light sources 63 and 64 are not lit. After the processing up to step ST106 is completed, the system transitions to a standby state (step ST107), and the first optical sensor PD1 measures pulse wave data. An externally disposed control device calculates blood oxygen saturation (SpO ) from the pulse wave data. ２ ) and calculate the blood oxygen saturation (SpO ２ The process for outputting the blood oxygen saturation (SpO ２ ) is the ratio of the amount of oxygen actually bound to hemoglobin to the total amount of oxygen that would be expected if all hemoglobin in the blood were oxygen-bound. ２ When acquiring blood oxygen saturation (SpO ２ ), a vein image acquired using red light and a vein image acquired using infrared light may be used.

[0057] [Operation Example 2 of the Detection Device] Next, an operation example 2 of calculating the heart rate by the detection device 100 will be described. FIG. 11 is a circuit diagram showing an example of the configuration of the detection device according to the first embodiment. FIG. 12 is a flowchart showing an example of the flow of processing related to the output of the heart rate according to the first embodiment. FIG. 13 is a timing waveform diagram showing an example of the operation of the third light source of the detection circuit according to the first embodiment. FIG. 14 is a plan view showing the pulse wave detection range of the third light source of the detection device according to the first embodiment. Note that the description of the components in FIG. 11 is omitted because they are the same as those in FIG. 7.

[0058] In the second operational example of the detection device 100, the switch circuits SSW2 and SSW3 are in the on state (see FIG. 11). The reset transistor RST is in the on state, and the sensor signal is reset (see FIG. 13), which is the initial state.

[0059] 12, the third light sources 63 and 64 are turned on to irradiate the detection object Fg with green light (step ST201). In step ST201, the reset transistor RST is in the off state (see FIG. 13).

[0060] Next, green light IL3 (see FIG. 14) reflected by the object Fg is irradiated onto the second optical sensor PD2 and the third optical sensor PD3, and the second optical sensor PD2 and the third optical sensor PD3 are read out (step ST202, see FIG. 13).

[0061] Next, the third light sources 63 and 64 are turned off, and the green light is stopped from being irradiated onto the second optical sensor PD2 and the third optical sensor PD3 (step ST203). In step ST203, the reset transistor RST is in the on state (see FIG. 13).

[0062] During the period when the third light sources 63 and 64 are turned on, they are statically lit (DC lit), and light is constantly irradiated onto the object to be detected Fg. In the processing up to step ST203, the third light sources 63 and 64 are turned on during the period when the first light source 61 and the second light source 62 are not lit. After the processing up to step ST203 is completed, the device transitions to a standby state (step ST204), and the second optical sensor PD2 and the third optical sensor PD3 measure pulse wave data. An external control device calculates the heart rate from the pulse wave data. Then, the processing related to the output of the heart rate is completed.

[0063] Fig. 15 is a plan view showing the pulse wave detection range of a detection device according to a comparative example. As shown in Fig. 15, detection device 100A according to the comparative example includes optical sensor PD4, first light source 61, second light source 62, third light sources 63 and 64, and light-shielding wall 57 on substrate 21. Optical sensor PD4, first light source 61, and second light source 62 are each surrounded by light-shielding wall 57.

[0064] In the detection device 100A according to the comparative example, compared to the detection device 100, the optical sensor PD4, the first light source 61, the second light source 62, and the third light sources 63 and 64 are arranged in a horizontal row on the substrate 21.

[0065] In the detection device 100A of the comparative example, the third light sources 63 and 64 each irradiate the object to be detected Fg, and the green light IL3 reflected by the object to be detected Fg is irradiated only onto a portion of the optical sensor PD4. Therefore, the amount of light that can be absorbed by the optical sensor PD4 is limited, and there is room for improving the light utilization efficiency.

[0066] In contrast, in the detection device 100 according to the first embodiment, as shown in FIG. 10, the red light IL1 and the infrared light IL2 reflected by the object to be detected Fg are irradiated onto the entire first optical sensor PD1, thereby enabling the detection of the pulse wave, thereby improving the efficiency of light utilization.

[0067] Furthermore, in the detection device 100 according to embodiment 1, as shown in FIG. 14, the green light IL3 reflected by the object to be detected Fg is irradiated onto the entire second optical sensor PD2 and the entire third optical sensor PD3, thereby enabling detection of the pulse wave, thereby improving the efficiency of light utilization.

[0068] In the detection device 100A according to the comparative example, the distance between the optical sensor PD4 and the range in which the first light source 61, second light source 62, and third light sources 63 and 64 are mounted is large.

[0069] In contrast, the detection device 100 of embodiment 1 has multiple openings OP that penetrate the optical sensor PD, and a first light source 61, a second light source 62, and third light sources 63 and 64 are arranged in each of the multiple openings OP, so that the distance between the light source and the area in which the photodiode components are mounted can be reduced, and the entire detection device 100 can be made smaller.

[0070] Although preferred embodiments of the present invention have been described above, the present invention is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible without departing from the spirit of the present invention. Appropriate modifications made without departing from the spirit of the present invention naturally fall within the technical scope of the present invention. At least one of various omissions, substitutions, and modifications of components can be made without departing from the gist of each of the above-described embodiments and modifications.

[0071] 100, 100A Detector Fg Object to be detected 11 Lower electrode 12 Lower buffer layer 13 Active layer 14 Upper buffer layer 15 Upper electrode 21 Substrate 55 First light-shielding wall 56 Second light-shielding wall 61 First light source 62 Second light source 63, 64 Third light source PD Photosensor PD1 First photosensor PD2 Second photosensor PD3 Third photosensor OP Opening OP1 First opening OP2 Second opening OP3 Third opening

Claims

1. A detection device comprising: a substrate; a light source which irradiates a detected object with light; and an organic photodiode which is laminated in the following order: a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode, wherein the organic photodiode is provided on the substrate, an opening which penetrates the organic photodiode exposes a surface of the substrate, and the light source is provided on the substrate at the opening.

2. The detection device according to claim 1, wherein a plurality of the lower electrodes are provided at different positions, a lower buffer layer, an active layer, an upper buffer layer and an upper electrode are stacked on the plurality of lower electrodes, a plurality of the openings are provided so as to penetrate each of the lower electrodes, and a plurality of the light sources are provided in each of the openings.

3. The detection device according to claim 2, wherein the opening is provided with a first light-shielding wall that surrounds the light source and blocks light incident on the light source, the first light-shielding wall protruding in a direction perpendicular to the substrate and being higher than the light source.

4. The detection device according to claim 3, wherein a second light-shielding wall for blocking light incident on the organic photodiode is provided on the outer periphery of the organic photodiode, the second light-shielding wall protruding in a direction perpendicular to the substrate and being higher than the organic photodiode.

5. The detection device described in claim 4, wherein the plurality of openings include a first opening, a second opening, and a third opening; the light source includes a first light source that emits red light, a second light source that emits infrared light, and a third light source that emits green light; the first opening is provided with the first light source and the second light source; the second opening and the third opening are each provided with the third light source; and the first opening is provided between the second opening and the third opening.

6. The detection device according to claim 5, wherein the first light source and the second light source are covered with a protrusion that has light-transmitting properties and protrudes in a direction perpendicular to the substrate.

7. The detection device according to claim 5 or 6, wherein the organic photodiode and the third light source are covered with a protective member having light-transmitting properties.

8. The detection device according to claim 7, wherein the third light source is turned on during a period in which the first light source and the second light source are not turned on, and the first light source and the second light source are turned on during a period in which the third light source is not turned on.

9. The detection device according to claim 8, further comprising an external control device, which calculates blood oxygen saturation from measured data when the first light source and the second light source are turned on, and calculates heart rate from measured data when the third light source is turned on.

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