Detection device

Abstract

This detection device comprises: a ring-shaped housing; a sensor substrate that is provided inside the housing and that is curved so as to follow the shape of the housing; a first optical sensor and a second optical sensor that are provided on the sensor substrate; a light source that is disposed inside the housing; and a plurality of wirings that connect each of the first optical sensor and the second optical sensor and a terminal provided to the sensor substrate. When expanded in a plate shape, the sensor substrate includes: a first side extending in a first direction; a second side parallel to the first side; and a notch formed by notching the second side. The notch includes an arc-shaped first section the entirety of which is curved, and the notch is provided between the first optical sensor and the second optical sensor in the first direction. The light source is disposed in a region overlapping the notch.

Description

Detection device

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

[0002] Optical sensors capable of detecting fingerprint patterns and vein patterns are known (see, for example, Patent Document 1). Such optical sensors are incorporated into the housings of wearable devices such as smartwatches, wristwatches, and wristbands to acquire biometric information such as pulse waves. The optical sensor includes a sensor substrate and multiple photodiodes mounted on the sensor substrate.

[0003] Japanese Patent Application Laid-Open No. 2009-32005

[0004] In a detection device using such an optical sensor, if the sensor substrate is deformed to fit the shape of the device's housing, stress may be concentrated at a specific location on the sensor substrate, which may result in a disconnection or a deterioration in the detection performance of the photodiode.

[0005] An object of the present invention is to provide a detection device that can suppress the concentration of stress on a sensor substrate.

[0006] A detection device according to one aspect of the present disclosure includes a ring-shaped housing, a sensor substrate provided inside the housing and curved to follow the shape of the housing, a first optical sensor and a second optical sensor provided on the sensor substrate, a light source disposed inside the housing, and a plurality of wirings connecting each of the first optical sensor and the second optical sensor to a terminal portion provided on the sensor substrate, wherein when the sensor substrate is unfolded into a flat plate, the sensor substrate has a first side extending in a first direction, a second side parallel to the first side, and a cutout portion formed by cutting out the second side, the cutout portion including a first arc-shaped portion having a curvature throughout, and is provided between the first optical sensor and the second optical sensor in the first direction, and the light source is disposed in an area overlapping the cutout portion.

[0007] A detection device according to one aspect of the present disclosure includes a ring-shaped housing, a sensor substrate provided inside the housing and curved to follow the shape of the housing, a first optical sensor and a second optical sensor provided on the sensor substrate, a light source disposed inside the housing, and a plurality of wirings connecting each of the first optical sensor and the second optical sensor to terminal portions provided on the substrate, wherein when the sensor substrate is unfolded into a flat plate, the sensor substrate has a first side extending in a first direction, a second side parallel to the first side, and an opening provided between the first side and the second side, wherein a first width of the sensor substrate between an outer edge of the opening and the first side is larger than a second width of the sensor substrate between the outer edge of the opening and the second side, the opening is provided between the first optical sensor and the second optical sensor in the first direction, and the light source is disposed in an area overlapping with the opening.

[0008] FIG. 1 is a schematic diagram showing an example of the appearance of a detection device according to the first embodiment, when a finger is placed inside the detection device, as viewed from the side of the housing. FIG. 2 is a cross-sectional view taken along II-II' in FIG. 1. FIG. 3 is a development view showing an example of a development of a flexible substrate of the detection device according to the first embodiment. FIG. 4 is a plan view showing an example of the configuration of the sensor substrate shown in FIG. 3. FIG. 5 is a cross-sectional view taken along V-V' in FIG. 4. FIG. 6 is a cross-sectional view taken along VI-VI' in FIG. 4. FIG. 7 is a plan view showing an example of the configuration of a sensor substrate according to a first modified example of the first embodiment. FIG. 8 is a plan view showing an example of the configuration of a sensor substrate according to a second modified example of the second embodiment. FIG. 9 is a plan view showing an example of the configuration of a sensor substrate according to a second modified example of the second embodiment.

[0009] Modes (embodiments) for carrying out the present disclosure 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.

[0010] In the present disclosure, 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.

[0011] 1 is a schematic diagram showing an example of the appearance of a detection device according to a first embodiment, when a finger is placed inside the detection device, as viewed from the side of the housing. FIG. 2 is a cross-sectional view taken along line II-II′ of FIG. 1.

[0012] As shown in FIG. 1 , the detection device 1 according to the first embodiment is a ring-shaped device that can be attached to and detached from the human body. The detection device 1 is worn on, for example, a finger Fg of the human body. The finger Fg includes 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 finger Fg on which it is worn. The finger Fg is an example of a measurement target. The measurement target is a living organism or a 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 1 is used as a ring.

[0013] Although the detection device 1 is a ring-shaped device, the invention is not limited to this, and the detection device 1 may be built into a wristwatch or a wristband to be configured as a wearable device.

[0014] 2, the detection device 1 includes a housing 200, a light source 60, a first optical sensor 10A, a second optical sensor 10B, and a flexible printed circuit board 70. The detection device 1 includes a battery (not shown) inside the housing 200 and operates on power from the battery.

[0015] The housing 200 is formed in a ring shape (annular shape) that can be worn on a finger Fg, and is a wearing member that is worn on a living body. As shown in Fig. 2, the housing 200 includes a first housing 210 and a second housing 220. The housing 200 is formed in a ring shape by integrating the first housing 210 and the second housing 220.

[0016] The first housing 210 is a member that comes into contact with the human body on which the housing 200 is worn. The first housing 210 houses the light source 60, the first optical sensor 10A, the second optical sensor 10B, etc. The first housing 210 is formed in a ring shape from a housing material such as a transparent synthetic resin or silicone.

[0017] 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 from a material such as metal or non-transparent synthetic resin. The housing 200 accommodates a flexible printed circuit board 70, on which the light source 60, the first optical sensor 10A, the second optical sensor 10B, etc. are mounted, inside the first housing 210. The flexible printed circuit board 70 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.

[0018] In this embodiment, the first optical sensor 10A and the second optical sensor 10B are provided so as to sandwich the light source 60 in the circumferential direction 200C. That is, the detection device 1 is arranged in the circumferential direction 200C with the first optical sensor 10A, the light source 60, and the second optical sensor 10B lined up in this order. By arranging the first optical sensor 10A and the second optical sensor 10B so as to sandwich the light source 60 in the circumferential direction 200C, the first optical sensor 10A and the second optical sensor 10B can detect light emitted by the light source 60 over a wide range of the housing 200.

[0019] Each of the first optical sensor 10A and the second optical sensor 10B detects light emitted by the light source 60 and reflected by a finger Fg or the like, directly incident light, etc. The first optical sensor 10A and the second optical sensor 10B are organic photodiodes (OPDs). The first optical sensor 10A is provided on the housing 200 so as to be adjacent to one end 61 of the light source 60 in the circumferential direction 200C of the housing 200. The second optical sensor 10B is provided on the housing 200 so as to be adjacent to the other end 62 of the light source 60 in the circumferential direction 200C of the housing 200.

[0020] 2, the light source 60 is provided inside the first housing 210 of the housing 200 and is configured to be able to irradiate light toward the finger Fg wearing the housing 200. For example, an inorganic LED (Light Emitting Diode) or an organic EL (OLED) is used as the light source 60. The light source 60 irradiates light of a predetermined wavelength. In this embodiment, the light source 60 has a plurality of light sources so as to be able to irradiate near-infrared light, red light, and green light.

[0021] Light emitted from the light source 60 is reflected by the surface of the object to be detected, such as a finger Fg, and enters the first optical sensor 10A and the second optical sensor 10B. This allows the detection device 1 to detect a fingerprint by detecting the shape of the projections and recesses on the surface of the finger Fg. Alternatively, the light emitted from the light source 60 may be reflected inside the finger Fg or pass through the finger Fg before entering the first optical sensor 10A and the second optical sensor 10B. This allows the detection device 1 to detect information about a living body inside the finger Fg. Examples of information about a living body include pulse waves, pulse rates, and blood vessel images of the finger or palm. That is, the detection device 1 may be configured as a fingerprint detection device that detects fingerprints, or a vein detection device that detects vascular patterns such as veins.

[0022] 3 is a development view showing an example of the development of the flexible substrate of the detection device according to the first embodiment. As shown in FIG. 3, the flexible printed circuit board 70 is formed in a deformable band shape, and is formed into a ring shape by connecting one end 71 and the other end 72. The flexible printed circuit board 70 has a first mounting area 73 and a second mounting area 74. The first mounting area 73 is an area where the light source 60 and the like are mounted. The second mounting area 74 is an area where the control circuit 51, the power supply circuit 52, and the like are mounted.

[0023] The sensor board 21 is mounted on the flexible printed circuit board 70 so as to straddle the vicinity of the light source 60 in the first mounting area 73. The first optical sensor 10A, the second optical sensor 10B, etc. are mounted on the sensor board 21. The sensor board 21 is an insulating board, and is formed, for example, in a strip shape using a film-like resin or the like, making it a deformable board. The sensor board 21 is provided inside the housing 200 and curves to fit the shape of the housing 200. The flexible printed circuit board 70 electrically connects the first optical sensor 10A and the second optical sensor 10B on the sensor board 21, the light source 60, and the control circuit 51.

[0024] 2 , the flexible printed circuit board 70 is housed inside the housing 200 so that the surface on which the first optical sensor 10A, the second optical sensor 10B, and the light source 60 are mounted is located on the inner periphery of the housing 200. If the flexible printed circuit board 70 is translucent, the first optical sensor 10A, the second optical sensor 10B, and the light source 60 may be mounted on the back surface opposite to the front surface. In this case, the light source 60 may be disposed so that it emits light toward the flexible printed circuit board 70 and the light that has passed through the flexible printed circuit board 70 is emitted toward the outside of the housing 200.

[0025] Next, the detailed configuration of the sensor substrate will be described with reference to Fig. 4. Fig. 4 is a plan view showing an example of the configuration of the sensor substrate shown in Fig. 3. Fig. 4 shows a plan view of the sensor substrate 21 when it is developed into a flat plate.

[0026] In the following description, the first direction Dx is a direction in a plane parallel to the sensor substrate 21. The second direction Dy is a direction in a plane parallel to the sensor 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 sensor substrate 21. Furthermore, "planar view" refers to the positional relationship when viewed from a direction perpendicular to the sensor substrate 21.

[0027] As shown in FIG. 4 , the sensor board 21 has a cutout portion 22 between both ends in the circumferential direction 200C of the housing 200, i.e., in the longitudinal direction (first direction Dx) of the sensor board 21. The sensor board 21 has a plurality of first optical sensors 10A mounted on one end 21A of the cutout portion 22, and a plurality of second optical sensors 10B mounted on the other end 21B of the cutout portion 22. In other words, the cutout portion 22 is located between the first optical sensors 10A and the second optical sensors 10B in the first direction Dx. The terminal portion 40 is provided at one end 21A of the sensor board 21 in the longitudinal direction. The terminal portion 40 supplies power from a power supply circuit 52 (see FIG. 3 ) to the first optical sensors 10A and the second optical sensors 10B.

[0028] The sensor substrate 21 also includes a connecting portion 23 corresponding to the portion where the cutout portion 22 is provided. The connecting portion 23 contacts the cutout portion 22 and connects the region of the sensor substrate 21 where the first optical sensor 10A is provided and the region of the sensor substrate 21 where the second optical sensor 10B is provided. This allows the region of the sensor substrate 21 where the first optical sensor 10A is provided and the region of the sensor substrate 21 where the second optical sensor 10B is provided to be integrally formed.

[0029] More specifically, the sensor substrate 21 has a first side S1 extending in the first direction Dx, a second side S2 extending in a direction parallel to the first side S1, and a third side S3 and a fourth side S4 extending in the second direction Dy between the first side S1 and the second side S2. The cutout portion 22 is formed by cutting out the second side S2 of the sensor substrate 21.

[0030] The cutout portion 22 includes a first portion 22a and a second portion 22b. The cutout portion 22 is provided in the first direction Dx in the order of the second portion 22b, the first portion 22a, and the second portion 22b. The first portion 22a is arc-shaped with a curvature over its entirety. More specifically, in the first portion 22a, the outer edge of the sensor substrate 21 is formed in a concave shape recessed from the second side S2 toward the first side S1, and has a continuous curved shape from one end side in the first direction Dx to the other end side in the first direction Dx. More preferably, in the first portion 22a, the outer edge of the sensor substrate 21 does not substantially include a straight portion. The curvature of the first portion 22a of the cutout portion 22 is, for example, 1 / (4×10 －３ ) or more than 1 / (3 x 10 －３ ) rad / m or less.

[0031] The second portion 22b is provided between the first portion 22a and the second side S2. More specifically, on the side of one end 21A of the sensor substrate 21, the second portion 22b is provided between one end of the first portion 22a and the second side S2. On the side of the other end 21B of the sensor substrate 21, the second portion 22b is provided between the other end of the first portion 22a and the second side S2. The second portions 22b each extend at an angle different from the tangent direction at the end of the first portion 22a.

[0032] The light source 60 is disposed in an area overlapping the cutout portion 22. The cutout portion 22 is formed over a distance in the first direction Dx that is longer than the length of the light source 60. The cutout portion 22 is formed over a distance in the second direction Dy that is longer than the length of the light source 60 and shorter than the length (width) of the sensor substrate 21. More specifically, the distance in the first direction Dx between one end side of the first portion 22a in the first direction Dx and the other end side in the first direction Dx is longer than the length of the light source 60. The distance in the second direction Dy between the center of the first portion 22a in the first direction Dx and the second side S2 of the sensor substrate 21 is longer than the length of the light source 60. This allows the cutout portion 22 of the sensor substrate 21 to secure a space for disposing the light source 60.

[0033] In the sensor substrate 21 of this embodiment, the cutout portions 22 are formed in a continuous arc shape, so that the width of the connecting portions 23 corresponding to the cutout portions 22 changes continuously in the second direction Dy. The connecting portions 23 have the smallest width at the center in the first direction Dx. Furthermore, the width of the connecting portions 23 in the second direction Dy increases continuously from the center in the first direction Dx toward the first optical sensor 10A or the second optical sensor 10B. This makes it possible to suppress local stress concentration on the sensor substrate 21, even when the sensor substrate 21 is curved in a ring shape to conform to the shape of the housing 200, compared to a configuration in which the cutout portions 22 do not have a continuous arc shape overall but are formed, for example, in a rectangular shape.

[0034] 4, it is assumed that stress will be large in the central portion of first portion 22a in the first direction Dx, i.e., in the portion where connecting portion 23 has the smallest width in the second direction Dy. Even in this case, because cutout portion 22 is provided in a continuous arc shape, stress is dispersed along the arc of cutout portion 22, and stress generated in the central portion of first portion 22a in the first direction Dx can be suppressed.

[0035] Furthermore, because the cutout portion 22 has the second portion 22b, no corner is formed between the end of the cutout portion 22 and the second side S2 of the sensor substrate 21. Therefore, when the sensor substrate 21 is deformed into a ring shape and stored inside the housing 200, the portion of the sensor substrate 21 corresponding to the second portion 22b can deform smoothly to conform to the shape of the housing 200, compared to a case where the second portion 22b is not provided and the end of the cutout portion 22 and the second side S2 of the sensor substrate 21 are connected at a substantially right angle. This makes it possible to suppress stress generation at the end of the sensor substrate 21 on the side of the second side S2 of the cutout portion 22.

[0036] Next, the configurations of the first optical sensor 10A and the second optical sensor 10B will be described with reference to Figures 4 to 6. Figure 5 is a cross-sectional view taken along line VV' in Figure 4. Figure 6 is a cross-sectional view taken along line VI-VI' in Figure 4.

[0037] 4, the first optical sensor 10A has a stacked configuration in which two lower electrodes 11 aligned in the first direction Dx are covered by one upper electrode 15A. The second optical sensor 10B has a stacked configuration in which two lower electrodes 11 aligned in the first direction Dx are covered by one upper electrode 15B. The upper electrode 15 includes the upper electrode 15A of the first optical sensor 10A and the upper electrode 15B of the second optical sensor 10B. The upper electrodes 15A and 15B have rectangular surfaces and are independent electrodes that are not electrically connected.

[0038] The first power supply electrode 25A and the second power supply electrode 25B are provided on the sensor substrate 21 and extend along the second direction Dy. The first power supply electrode 25A is provided between one end 21A of the sensor substrate 21 and the first optical sensor 10A in the first direction Dx. The second power supply electrode 25B is provided between the other end 21B of the sensor substrate 21 and the second optical sensor 10B in the first direction Dx. The first power supply electrode 25A is electrically connected to a terminal 40 of the sensor substrate 21 via a first wiring 26A, and a power signal is supplied from a power supply circuit 52 (see FIG. 3 ) via the terminal 40. The second power supply electrode 25B is electrically connected to a terminal 40 of the sensor substrate 21 via a second wiring 26B, and a power signal is supplied from the power supply circuit 52 via the terminal 40.

[0039] The upper electrode 15A of the first optical sensor 10A is connected to the first power supply electrode 25A via the conductive material 24 and is electrically connected to the terminal 40 via the first wiring 26A connected to the first power supply electrode 25A. The upper electrode 15B of the second optical sensor 10B is connected to the second power supply electrode 25B via the conductive material 24 and is electrically connected to the terminal 40 via the second wiring 26B connected to the second power supply electrode 25B. As a result, the upper electrode 15A and the upper electrode 15B are each supplied with power from the independent power systems of the first power supply electrode 25A and the second power supply electrode 25B. The conductive material 24 is made of a conductive material and covers the entire surface of the first power supply electrode 25A or the second power supply electrode 25B, electrically connecting the first power supply electrode 25A to the upper electrode 15A and the second power supply electrode 25B to the upper electrode 15B. The upper electrode 15A and the first power supply electrode 25A, and the upper electrode 15B and the second power supply electrode 25B may be directly connected without the conductive material 24 interposed therebetween.

[0040] The third wiring 26C connects each of the lower electrodes 11 of the first optical sensor 10A and the second optical sensor 10B to a terminal 40 provided on the sensor substrate 21. The third wiring 26C connected to the lower electrode 11 of the first optical sensor 10A is connected to the terminal 40 through a region on the first side S1 of the sensor substrate 21. The third wiring 26C connected to the lower electrode 11 of the second optical sensor 10B is connected to the terminal 40 through a region on the second side S2 of the sensor substrate 21 and the connecting portion 23. The multiple third wirings 26C are connected to a detection circuit included in the control circuit 51 via the terminal 40 and signal lines of the flexible printed circuit board 70. In other words, the detection circuit included in the control circuit 51 is electrically connected to the lower electrodes 11 of the first optical sensor 10A and the second optical sensor 10B via signal lines. The detection circuit may be formed as a circuit separate from the control circuit 51.

[0041] The first power supply electrode 25A and the second power supply electrode 25B receive a power supply signal from a power supply circuit 52 via the terminal portion 40, and supply the power supply signal to the upper electrode 15A and the upper electrode 15B. In the example shown in Fig. 4, the first power supply electrode 25A and the second power supply electrode 25B are formed in a substantially rectangular shape extending in the second direction Dy in a plan view, and have the same area (size).

[0042] As shown in FIG. 5, the photodiode PD constituting the first optical sensor 10A is provided on the sensor substrate 21 via an insulating layer 27.

[0043] The third wiring 26C is provided on the upper surface of the sensor substrate 21. The third wiring 26C is formed, for example, of a metal wiring, and is formed of a material having better conductivity than the lower electrode 11 of the first optical sensor 10A. The third wiring 26C is provided in a layer between the sensor substrate 21 and the photodiode PD in the third direction Dz. The third wiring 26C is electrically connected to the terminal portion 40 on the sensor substrate 21 (see FIG. 4 ). Note that the third wiring 26C may be formed, for example, in the same layer as the lower electrode 11, or may be formed of metal. The insulating layer 27 is provided on the sensor substrate 21, covering the third wiring 26C. The insulating layer 27 may be an inorganic insulating film or an organic insulating film.

[0044] The photodiode PD is provided as a sensor element on the insulating layer 27. The photodiode 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 (upper electrode 15A). In the photodiode PD, the lower electrode 11, the lower buffer layer 12, the active layer 13, the upper buffer layer 14, and the upper electrode 15 are stacked in this order in a third direction Dz perpendicular to the sensor substrate 21.

[0045] The lower electrode 11 is made of a light-transmitting conductive material such as ITO (Indium Tin Oxide).

[0046] The characteristics (for example, voltage-current characteristics and resistance value) of the active layer 13 change depending on the light irradiated thereto. An organic material is used as the material of the active layer 13. Specifically, the active layer 13 has a bulk heterostructure in which a p-type organic semiconductor and an n-type organic semiconductor, an n-type fullerene derivative (PCBM), are mixed. For example, a low-molecular organic material, C ６０ (fullerene), PCBM (phenyl C ６１ Phenyl C61-butyric acid methyl ester), CuPc (Copper Phthalocyanine), F １６ CuPc (fluorinated copper phthalocyanine), rubrene (5,6,11,12-tetraphenyltetracene), PDI (a derivative of perylene), or the like can be used.

[0047] The active layer 13 can be formed by a vapor deposition (dry process) using these low molecular weight organic materials. In this case, the active layer 13 is formed by, for example, CuPc and F １６ CuPc laminated film or rubrene and C ６０ The active layer 13 may be a laminated film of the above-mentioned low molecular weight organic material and high molecular weight organic material. The active layer 13 may also be formed by a coating process (wet process). In this case, the active layer 13 is made of a material that combines the above-mentioned low molecular weight organic material and 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 may be a film in which P3HT and PCBM are mixed, or a film in which F8BT and PDI are mixed.

[0048] 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. One of the lower buffer layer 12 and the upper buffer layer 14 is a hole transport layer. The other of the lower buffer layer 12 and the upper buffer layer 14 is an electron transport layer. The material of the hole transport layer is a metal oxide layer. As the metal oxide layer, tungsten oxide (WO ３), molybdenum oxide, etc. The material of the electron transport layer is ethoxylated polyethyleneimine (PEIE).

[0049] 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.

[0050] The upper electrode 15 is provided on the upper buffer layer 14. The upper electrode 15 is formed continuously over the entire photodiode PD of the first optical sensor 10A. In other words, the upper electrode 15 is provided continuously over the multiple photodiodes 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 15a of the upper electrode 15 is electrically connected to a conductive material 24. The conductive material 24 is electrically connected to a first power supply electrode 25A and supplies a power signal from the first power supply electrode 25A to the upper electrode 15.

[0051] The sealing film 90 is provided on the upper electrode 15. The sealing film 90 is made of an inorganic film such as a silicon nitride film or an aluminum oxide film, or a resin film such as acrylic. The sealing film 90 is not limited to a single layer, but may be a laminated film of two or more layers combining the inorganic film and the resin film. The sealing film 90 effectively seals the photodiode PD and can prevent moisture from entering from the upper surface side. In this embodiment, the photodiode PD is configured to protect the terminal portion 40, the sensor substrate 21, etc. by covering the sealing film 90 to a part of the terminal portion 40 with a resin 91.

[0052] As shown in FIG. 6 , the two lower electrodes 11 of the second optical sensor 10B are provided in a different region of the sensor substrate 21 from the lower electrodes 11 of the first optical sensor 10A. The lower electrodes 11 are covered with a lower buffer layer 12, an active layer 13, an upper buffer layer 14, and an upper electrode 15B. The photodiode PD constituting the second optical sensor 10B has the same configuration as the photodiode PD of the first optical sensor 10A. That is, the photodiode PD of the second optical sensor 10B has a lower electrode 11, a lower buffer layer 12, an active layer 13, an upper buffer layer 14, and an upper electrode 15B. In this embodiment, the first optical sensor 10A and the second optical sensor 10B are organic photodiodes.

[0053] In the second optical sensor 10B, a portion of an end of the upper surface 15a of the upper electrode 15 is electrically connected to the conductive material 24, and the conductive material 24 is electrically connected to the second power supply electrode 25B. In the second optical sensor 10B, a power supply signal is supplied from the second power supply electrode 25B to the upper electrode 15. In the second optical sensor 10B, a sealing film 90 is provided on the upper electrode 15, the conductive material 24, etc., so that the photodiode PD is well sealed.

[0054] In this embodiment, as described above, the sensor substrate 21 is provided with the cutout portion 22, and the cutout portion 22 is provided in a continuous arc shape over the entire surface. This makes it possible to suppress the occurrence of cracks, buckling, and the like in the sensor substrate 21 due to stress concentration. As a result, in this embodiment, it is possible to suppress breakage of the wiring (second wiring 26B and third wiring 26C) provided in the coupling portion 23 and damage to the photodiode PD.

[0055] The configurations shown in FIGS. 1 to 6 are merely examples, and the configurations of the sensor substrate 21, photodiode PD, and the like can be modified as appropriate. For example, the shape of the cutout portion 22 of the sensor substrate 21 is not limited to the configuration shown in FIG. 4. For example, the radius of curvature (curvature) of the first portion 22a of the cutout portion 22 is not limited to a constant value and may vary along the arc. Alternatively, the cutout portion 22 of the sensor substrate 21 may not have the second portion 22b. Although the detection device 1 has four photodiodes PD, the number may be three or less, or five or more. Although the housing 200 shown in FIG. 2 is ring-shaped and has a curvature along its entire circumference, the housing 200 may have a flat area on a portion of its circumference, such as the area where the light source 60 is located.

[0056] 7 is a plan view showing a configuration example of a sensor substrate according to a first modification of the first embodiment. In the following description, the same components as those described in the above embodiment are denoted by the same reference numerals, and redundant description will be omitted.

[0057] As shown in Fig. 7 , in the detection device 1A according to the first modification, arc-shaped portions having curvature are formed at the corners of the cutout portion 22 of the sensor substrate 21. More specifically, the cutout portion 22 includes curved portions 22c and 22d and straight portions 22e, 22f, and 22g. The curved portions 22c and 22d are each arc-shaped having curvature. The curved portions 22c and 22d connect the adjacent straight portions 22e, 22f, and 22g along the outer edge of the cutout portion 22.

[0058] The straight line portion 22e extends in the second direction Dy, with one end connected to the second side S2 of the sensor substrate 21 and the other end connected to the curved line portion 22c. The straight line portion 22f extends in the first direction Dx, with one end connected to the curved line portion 22c and the other end connected to the curved line portion 22d. The straight line portion 22g extends in the second direction Dy, with one end connected to the curved line portion 22d and the other end connected to the second side S2 of the sensor substrate 21.

[0059] In the first modification, the corners of the cutout portion 22, where stress concentration is likely to occur, are provided with the arc-shaped curved portions 22c and 22d having curvature, thereby effectively suppressing the occurrence of stress in the sensor substrate 21. Furthermore, in the first modification, the area of ​​the cutout portion 22 can be increased to ensure space for arranging the light source 60.

[0060] In the first modified example, the linear portions 22e and 22g of the cutout portion 22 are directly connected to the second side S2 of the sensor substrate 21, but this is not limiting. For example, the cutout portion 22 may have the second portion 22b between the linear portions 22e and 22g and the second side S2, similar to the first embodiment.

[0061] 8 is a plan view showing a configuration example of a sensor substrate according to a second embodiment. In the second embodiment and a second modified example described later, the configurations of the first optical sensor 10A and the second optical sensor 10B are the same as those in the first embodiment (see FIGS. 5 and 6), and therefore repeated description will be omitted.

[0062] 8 , in the detection device 1B according to the second embodiment, an opening 28 is provided in the sensor substrate 21. The opening 28 is formed in the first direction Dx between the region of the sensor substrate 21 where the first optical sensor 10A is provided and the region of the sensor substrate 21 where the second optical sensor 10B is provided. The opening 28 is also formed in the second direction Dy between the first side S1 and the second side S2 of the sensor substrate 21. The opening 28 has a substantially rectangular shape with long sides aligned with the first side S1 and the second side S2, and the corners are smoothly curved in an arc shape.

[0063] The sensor substrate 21 has connecting portions 23A and 23B that contact the opening 28 and extend in the first direction Dx. The connecting portion 23A is provided between the outer edge of the opening 28 and the first side S1. The connecting portion 23B is provided between the outer edge of the opening 28 and the second side S2. The region of the sensor substrate 21 where the first optical sensor 10A is provided and the region where the second optical sensor 10B is provided are integrally connected by the two connecting portions 23A and 23B.

[0064] More specifically, the outer edge of the opening 28 has straight line portions 28a, 28b, 28c, and 28d and four curved line portions 28e. The straight line portion 28a extends in a direction (first direction Dx) parallel to the first side S1 of the sensor substrate 21. The straight line portion 28b extends in a direction (first direction Dx) parallel to the second side S2 of the sensor substrate 21. The straight line portions 28c and 28d are provided between the straight line portions 28a and 28b and extend in a direction (second direction Dy) parallel to the third side S3 and the fourth side S4 of the sensor substrate 21, respectively.

[0065] Each of the four curved portions 28e has an arc shape with a certain curvature. The four curved portions 28e are provided between adjacent straight portions 28a, 28b, 28c, and 28d along the outer edge of the opening 28. As a result, the adjacent straight portions 28a, 28b, 28c, and 28d are smoothly connected by the curved portions 28e.

[0066] The light source 60 is disposed in an area overlapping with the opening 28. The opening 28 is formed over a distance in the first direction Dx that is longer than the length of the light source 60. The opening 28 is formed over a distance in the second direction Dy that is longer than the length of the light source 60 and shorter than the length (width) of the sensor substrate 21. This allows the opening 28 of the sensor substrate 21 to secure a space for disposing the light source 60.

[0067] The sensor substrate 21 of this embodiment is provided with arc-shaped curved portions 28e having curvature at the corners of the opening 28, where stress concentration is likely to occur. This allows the detection device 1B of the second embodiment to suppress the generation of stress in the sensor substrate 21.

[0068] Furthermore, connecting portion 23A of sensor substrate 21 is formed between first side S1 and straight portion 28a, which is the outer edge of opening 28. Connecting portion 23B of sensor substrate 21 is formed between second side S2 and straight portion 28b, which is the outer edge of opening 28. As a result, in detection device 1B of the second embodiment, it is possible to prevent twisting of sensor substrate 21, for example, when sensor substrate 21 is deformed into a ring shape along housing 200.

[0069] The first width in the second direction Dy of the connecting portion 23A of the sensor substrate 21 is larger than the second width in the second direction Dy of the connecting portion 23B of the sensor substrate 21. This allows the sensor substrate 21 to secure space for providing the second wiring 26B and the third wiring 26C.

[0070] 9 is a plan view showing a configuration example of a sensor substrate according to a second modification of embodiment 2. As shown in Fig. 9, in detection device 1C according to the second modification, the outer edge of opening 28A on the first side S1 side is arc-shaped.

[0071] More specifically, the outer edge of opening 28A has a first curved portion 28Aa, a straight portion 28Ab, and two second curved portions 28Ac and 28Ad. Straight portion 28Ab extends in a direction (first direction Dx) parallel to second side S2 of sensor substrate 21. First curved portion 28Aa is located closer to first side S1 than straight portion 28Ab and has an arc shape with a curvature overall.

[0072] The two second curved portions 28Ac, 28Ad are arc-shaped with smaller radii of curvature than the first curved portion 28Aa, and connect the straight portion 28Ab and the first curved portion 28Aa. The second curved portion 28Ac connects one end (the left end in FIG. 9 ) of the straight portion 28Ab to one end (the left end in FIG. 9 ) of the first curved portion 28Aa. The second curved portion 28Ad connects the other end (the right end in FIG. 9 ) of the straight portion 28Ab to the other end (the right end in FIG. 9 ) of the first curved portion 28Aa.

[0073] In this modification, the first curved portion 28Aa of the outer edge of the opening 28A, which is close to the first side S1 (connecting portion 23A) of the sensor substrate 21, is formed in an arc shape having a curvature throughout. This allows stress to be dispersed along the first curved portion 28Aa, and stress concentration at the center portion of the connecting portion 23A in the first direction Dx (the portion with the smallest width in the second direction Dy) can be suppressed. Therefore, in this modification, breakage of the second wiring 26B and the third wiring 26C provided in the connecting portion 23A can be suppressed.

[0074] The shape, size, width, etc. of the openings 28, 28A shown in the second embodiment and the second modified example are merely examples and can be changed as appropriate. For example, the openings 28 in the second embodiment are substantially rectangular with long sides along the first direction Dx, but are not limited to this and may be other shapes, such as substantially square.

[0075] Although preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible within the scope of the present disclosure. Appropriate modifications made within the scope of the present disclosure naturally fall within the technical scope of the present disclosure. At least one of various omissions, substitutions, and modifications of components can be made within the scope of the gist of each of the above-described embodiments and modifications.

[0076] REFERENCE SIGNS LIST 1, 1A, 1B, 1C Detecting device 10A First optical sensor 10B Second optical sensor 11 Lower electrode 12 Lower buffer layer 13 Active layer 14 Upper buffer layer 15, 15A, 15B Upper electrode 21 Sensor substrate 22 Notch portion 22a First portion 22b Second portion 23, 23A, 23B Connecting portion 26A First wiring 26B Second wiring 26C Third wiring 28, 28A Opening 40 Terminal portion 60 Light source 70 Flexible printed circuit board 200 Housing PD Photodiode

Claims

1. A detection device comprising: a ring-shaped housing; a sensor board provided inside the housing and curved to follow the shape of the housing; a first optical sensor and a second optical sensor provided on the sensor board; a light source disposed inside the housing; and a plurality of wirings connecting each of the first optical sensor and the second optical sensor to a terminal portion provided on the sensor board, wherein the sensor board, when developed into a flat plate, has a first side extending in a first direction, a second side parallel to the first side, and a cutout portion formed by cutting out the second side, the cutout portion including a first portion having a curvature throughout, and is provided between the first optical sensor and the second optical sensor in the first direction, and the light source is disposed in a region overlapping with the cutout portion.

2. The detection device according to claim 1, wherein the cutout portion includes a second portion provided between the first portion and the second side, and the second portion extends in a direction different from a tangent direction at an end of the first portion.

3. The detection device according to claim 1, wherein each of the first optical sensor and the second optical sensor is formed by stacking a lower electrode, a lower buffer layer, an active layer, an upper buffer layer and an upper electrode on the sensor substrate in that order, and the wiring is connected to the lower electrode.

4. The detection device according to claim 1, wherein the housing is in the shape of a ring that can be worn on a finger.

5. A detection device comprising: a ring-shaped housing; a sensor board provided inside the housing and curved along the shape of the housing; a first optical sensor and a second optical sensor provided on the sensor board; a light source disposed inside the housing; and a plurality of wirings connecting each of the first optical sensor and the second optical sensor to a terminal portion provided on the sensor board, wherein the sensor board, when developed into a flat plate, has a first side extending in a first direction, a second side parallel to the first side, and an opening provided between the first side and the second side, wherein a first width of the sensor board between an outer edge of the opening and the first side is larger than a second width of the sensor board between the outer edge of the opening and the second side, wherein the opening is provided between the first optical sensor and the second optical sensor in the first direction, and the light source is disposed in a region overlapping with the opening.

6. The detection device according to claim 5, wherein the outer edge of the opening on the first side is arc-shaped.

7. The detection device according to claim 5, wherein each of the first optical sensor and the second optical sensor is formed by stacking a lower electrode, a lower buffer layer, an active layer, an upper buffer layer and an upper electrode on the sensor substrate in that order, and the wiring is connected to the lower electrode.

8. The detection device according to claim 5, wherein the housing is in the shape of a ring that can be worn on a finger.

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