Detection device

Abstract

Provided is a detection device capable of suppressing direct light from a light source to an optical sensor and improving detection accuracy. The detection device has a first optical sensor and a second optical sensor in each of which a lower electrode, a lower buffer layer, an active layer, an upper buffer layer, and an upper electrode are laminated on a substrate in this order. The detection device comprises, in a plan view, a notch portion and a light-shielding layer that covers the first optical sensor and the second optical sensor. The light-shielding layer is provided with a plurality of openings. The openings include a first opening, a second opening, and a third opening. The first opening is provided with a first light-shielding wall surrounding the periphery of the light source. The second opening is provided with a second light-shielding wall surrounding the periphery of the first optical sensor. The third opening is provided with a third light-shielding wall surrounding the periphery of the second optical sensor.

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). Among these optical sensors, a sensor having multiple photodiodes with an active layer made of an organic semiconductor material is known. The organic semiconductor material is disposed between a lower electrode and an upper electrode, and a signal line is electrically connected to the lower electrode of the photodiode for outputting a detection signal to a detection circuit.

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

[0004] In conventional technology, light from the light source directly enters the optical sensor, which may prevent accurate measurement of the pulse wave.

[0005] An object of the present invention is to provide a detection device that can block direct light irradiated from a light source onto an optical sensor, thereby improving detection accuracy.

[0006] A detection device according to one aspect of the present invention includes a substrate having a cutout between both ends in a first direction, a terminal provided at one end of the substrate in the first direction, a first optical sensor provided on the substrate between the cutout and the terminal, a second optical sensor provided on the substrate between the cutout and the other end of the substrate, and a light source disposed in the cutout of the substrate, wherein each of the first optical sensor and the second optical sensor includes a lower electrode, a lower buffer layer, and a light source disposed in the cutout of the substrate. an active layer, an upper buffer layer, and an upper electrode are stacked in this order, and a light-shielding layer is provided that covers the first photosensor and the second photosensor in a planar view, and the light-shielding layer is provided with a plurality of openings, the openings including a first opening, a second opening, and a third opening, a first light-shielding wall that surrounds the light source is provided in the first opening, a second light-shielding wall that surrounds the first photosensor is provided in the second opening, and a third light-shielding wall that surrounds the second photosensor is provided in the third opening.

[0007] FIG. 1 is a schematic diagram showing an example of the appearance of a detection device according to an embodiment, 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 developed view showing an example of the optical sensor of the detection device shown in FIG. 1. FIG. 4 is a schematic top view showing an example of the configuration of the substrate shown in FIG. 3. FIG. 5 is a schematic cross-sectional view showing an example of the stacked configuration of the optical sensor taken along the line V-V' in FIG. 4. FIG. 6 is a schematic cross-sectional view showing an example of the stacked configuration of the optical sensor taken along the line VI-VI' in FIG. 4. FIG. 7 is a plan view of the light-shielding layer of the detection device according to an embodiment. FIG. 8 is a schematic cross-sectional view taken along the line VIII-VIII' in FIG. 7. FIG. 9 is a plan view of the back side of the light-shielding layer of the detection device according to an embodiment. FIG. 10 is a schematic cross-sectional view taken along the line X-X' in FIG. 9. FIG. 11 is a schematic top view showing the light-shielding layer and the optical sensor assembled together. Fig. 12 is a cross-sectional view showing the arrangement of the light source, the optical sensor, and the light-shielding wall along the XII-XII' cross section shown in Fig. 11. Fig. 13 is a cross-sectional view showing the arrangement of the light source, the optical sensor, and the light-shielding wall along the XIII-XIII' cross section shown in Fig. 11.

[0008] Modes for carrying out the invention (embodiments) will be described in detail with reference to the drawings. The present invention 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. The disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the invention are naturally included within the scope of the present invention. Furthermore, for clarity of explanation, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present invention. Furthermore, in this specification 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] (Embodiments) Fig. 1 is a schematic diagram showing an example of the appearance of a detection device according to an embodiment, 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 developed view showing an example of an optical sensor of the detection device shown in Fig. 1. Fig. 4 is a schematic top view showing an example of the configuration of the substrate shown in Fig. 3. Fig. 5 is a schematic cross-sectional view showing an example of the stacked configuration of the optical sensor taken along the line V-V' in Fig. 4. Fig. 6 is a schematic cross-sectional view showing an example of the stacked configuration of the optical sensor taken along the line VI-VI' in Fig. 4.

[0011] The detection device 1 shown in FIG. 1 is a ring-shaped device that can be attached to and detached from the human body, and is worn on 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 body 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 body or part of a living body, 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.

[0012] 2, the detection device 1 includes a housing 200, a light source 60, a first optical sensor 10A, a second optical sensor 10B, a flexible printed circuit board 70, and a light-shielding layer 50 (see FIG. 7), which will be described later. The detection device 1 includes a battery (not shown) inside the housing 200 and is operated by power from the battery.

[0013] The housing 200 is formed in a ring shape (annular shape) that can be worn on a finger Fg and is a wearable member that is worn on 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 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 using a housing material such as optically 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 metal or optically non-transparent synthetic resin. The housing 200 accommodates the 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, for example, by forming the housing 200 in a ring shape using a mold and filling the surrounding area with a filling material.

[0014] 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 122, the power supply circuit 123, and the like are mounted. The flexible printed circuit board 70 has a substrate 21 mounted so as to straddle the vicinity of the light source 60 in the first mounting area 73. The substrate 21 is a sensor substrate on which the first optical sensor 10A, the second optical sensor 10B, and the like are mounted. The flexible printed circuit board 70 electrically connects the light source 60, the first optical sensor 10A, the second optical sensor 10B, and the like to the control circuit 122.

[0015] 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.

[0016] The detection device 1 further includes a substrate 21 and a terminal portion 40. The substrate 21 is a rectangular insulating substrate, for example, formed in a strip shape using a film-like resin or the like. The substrate 21 is a deformable, flexible substrate on which the first optical sensor 10A and the second optical sensor 10B are mounted. The substrate 21 is attached to the flexible printed circuit board 70, thereby positioning the first optical sensor 10A and the second optical sensor 10B on both sides of the light source 60 in the circumferential direction 200C of the housing 200. The substrate 21 has a cutout portion 22 between both ends of the substrate 21 in the circumferential direction 200C of the housing 200, i.e., in the longitudinal direction. The substrate 21 has the first optical sensor 10A mounted on one end 21A of the substrate 21 and the second optical sensor 10B mounted on the other end 21B of the substrate 21, sandwiching the cutout portion 22. The terminal portion 40 is provided at one end 21A of the substrate 21 in the longitudinal direction. The terminal portion 40 supplies power from the power supply circuit 123 to the first optical sensor 10A and the second optical sensor 10B.

[0017] 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 faces the inner circumferential surface 200B 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.

[0018] 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 light emitting diode (LED) or an organic light emitting diode (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 capable of irradiating near-infrared light, red light, and green light.

[0019] Light emitted from the light source 60 is reflected by a detection object 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.

[0020] 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.

[0021] As shown in FIG. 3 , the first optical sensor 10A and the second optical sensor 10B each have a photodiode PD (see FIG. 4 ), which is an organic photodiode. Each of the first optical sensor 10A and the second optical sensor 10B has two lower electrodes 11 aligned along the circumferential direction 200C. The first optical sensor 10A and the second optical sensor 10B are mounted on a single substrate 21 and electrically connected to the flexible printed circuit board 70 via the substrate 21. The substrate 21 has a cutout portion 22 between the first optical sensor 10A and the second optical sensor 10B in the circumferential direction 200C of the housing 200. The cutout portion 22 will be described later.

[0022] In the following description, the first direction Dx is a direction in a plane parallel to the substrate 21 and is the same direction as the circumferential direction 200C. 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 with the first direction Dx without being perpendicular thereto. 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.

[0023] As shown in FIG. 4 , the first optical sensor 10A is configured such that two lower electrodes 11 aligned in the first direction Dx are covered by one upper electrode 15A. The second optical sensor 10B is configured such that 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. Each of the upper electrode 15A and the upper electrode 15B covers two lower electrodes 11 in a plan view. The upper electrodes 15A and 15B have rectangular surfaces and are independent electrodes that are not electrically connected.

[0024] The substrate 21 has a first power supply electrode 25A and a second power supply electrode 25B extending along the second direction Dy. The first power supply electrode 25A is provided between one end 21A of the 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 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 substrate 21 via a first wiring 26A, and receives power from a power supply circuit 123 (see FIG. 3 ) via the terminal 40. The second power supply electrode 25B is electrically connected to the terminal 40 of the substrate 21 via a second wiring 26B, and receives a power signal from the power supply circuit 123 via the terminal 40.

[0025] 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 may be directly connected to the first and second power supply electrodes 25A and 25B without the conductive material 24 therebetween.

[0026] The lower electrodes 11 of the first optical sensor 10A and the second optical sensor 10B are each connected to the terminal portion 40 via the third wiring 26C. The plurality of third wirings 26C of the substrate 21 are connected to the detection circuit 48 of the control circuit 122 via the terminal portion 40 and signal lines of the flexible printed circuit board 70. In other words, the detection circuit 48 is electrically connected to the lower electrodes 11 of the first optical sensor 10A and the second optical sensor 10B via the signal lines. The detection circuit 48 may be formed as a circuit separate from the control circuit 122.

[0027] An adhesive layer 240 is provided so as to entirely cover the first power supply electrode 25A and the conductive material 24. The adhesive layer 240 bonds the light-shielding layer 50, which will be described later with reference to Fig. 7, to the substrate 21. The adhesive layer 240 is, for example, a double-sided tape. The adhesive layer 240 may also be an adhesive.

[0028] The first power supply electrode 25A and the second power supply electrode 25B receive a power supply signal from the power supply circuit 123 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).

[0029] 5, the first optical sensor 10A includes a substrate 21 and a photodiode PD. In this embodiment, the first optical sensor 10A further includes a third wiring 26C, an insulating layer 27, and a sealing film 90.

[0030] The substrate 21 has a third wiring 26C provided on its upper surface. 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 photodiode PD. The third wiring 26C is provided in a layer between the substrate 21 and the photodiode PD in the third direction Dz. The third wiring 26C is electrically connected to a terminal portion 40 in the 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. An insulating layer 27 is provided on the substrate 21, covering the third wiring 26C. The insulating layer 27 may be an inorganic insulating film or an organic insulating film.

[0031] 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 (15A). In the photodiode 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.

[0032] The lower electrode 11 is an anode electrode of the photodiode PD and is formed of a light-transmitting conductive material such as indium tin oxide (ITO). The characteristics (e.g., voltage-current characteristics and resistance value) of the active layer 13 change 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).

[0033] 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.

[0034] 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 to reach the lower electrode 11 or the upper electrode 15. The lower buffer layer 12 (hole transport layer) is in direct contact with the lower electrode 11, and is also provided in the region between adjacent lower electrodes 11. The active layer 13 is in direct contact with the lower buffer layer 12. The material of the hole transport layer is a metal oxide layer. As the metal oxide layer, tungsten oxide (WO ３ ), molybdenum oxide, etc. are used.

[0035] 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.

[0036] 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.

[0037] The upper electrode 15 is provided on the upper buffer layer 14. The upper electrode 15 is a cathode electrode of the photodiode PD and is continuously formed across the entire first optical sensor 10A and the second optical sensor 10B. In other words, the upper electrode 15 is continuously provided on the multiple photodiodes PD. The upper electrode 15 faces the multiple lower electrodes 11, sandwiching the lower buffer layer 12, the active layer 13, and the upper buffer layer 14 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 150 of the upper electrode 15 is electrically connected to the conductive material 24. The conductive material 24 is electrically connected to the first power supply electrode 25A and supplies a power signal from the first power supply electrode 25A to the upper electrode 15. In the first optical sensor 10A, the photodiode PD is well sealed by the sealing film 90 provided on the upper electrode 15, the conductive material 24, etc. The upper electrode 15 may be a laminated film of a plurality of light-transmitting conductive materials.

[0038] The sealing film 90 is provided on the upper electrode 15. The sealing film 90 is light-transmitting and 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. In this embodiment, the first optical sensor 10A is configured to protect the terminal portion 40, the substrate 21, etc. by covering the sealing film 90 to a portion of the terminal portion 40 with a resin 91.

[0039] As shown in FIG. 6 , the second optical sensor 10B has two lower electrodes 11 in a region of the substrate 21 different 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 15 (15B). In this embodiment, the second optical sensor 10B has a substrate 21, a photodiode PD, a third wiring 26C, and an insulating layer 27. The photodiode PD, the third wiring 26C, and the insulating layer 27 have the same configuration as the photodiode PD, the third wiring 26C, and the insulating layer 27 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 15 (15B).

[0040] In the second optical sensor 10B, a portion of an end of an upper surface 150 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.

[0041] 4, the substrate 21 has an area for the first optical sensor 10A and an area for the second optical sensor 10B, and is formed as a single, integrally formed common substrate. The substrate 21 has a cutout portion 22 formed between the area for the first optical sensor 10A and the area for the second optical sensor 10B in the first direction Dx. The substrate 21 has the cutout portion 22 between the first optical sensor 10A and the second optical sensor 10B, and a connecting portion 23 that contacts the cutout portion 22 and is located between the first optical sensor 10A and the second optical sensor 10B.

[0042] 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 but shorter than the length (width) of the substrate 21. The substrate 21 is integrally formed by connecting the regions of the first optical sensor 10A and the second optical sensor 10B at a connecting portion 23 of the cutout portion 22. The cutout portion 22 is formed in a shape that allows the light source 60 to be disposed therein. In this embodiment, the cutout portion 22 is formed in a substantially rectangular shape in a plan view, but may be shaped, for example, semicircular, triangular, polygonal, or the like. The connecting portion 23 is provided with a second wiring 26B and a third wiring 26C.

[0043] The terminal unit 40 is electrically connected to the flexible printed circuit board 70 (see FIG. 5 ). The terminal unit 40 is a device for electrically connecting the first optical sensor 10A area and the second optical sensor 10B area of ​​the substrate 21 to the control circuit 122 and the power supply circuit 123 of the flexible printed circuit board 70. The terminal unit 40 is mounted on the substrate 21 and electrically connected to the first wiring 26A, the second wiring 26B, the third wiring 26C, etc. of the substrate 21. The first wiring 26A, the second wiring 26B, and the third wiring 26C are metal wires on the same layer of the substrate 21. The terminal unit 40 supplies a power signal (power) from the power supply circuit 123 to the first optical sensor 10A via the first wiring 26A. The terminal unit 40 supplies a power signal (power) from the power supply circuit 123 to the second optical sensor 10B via the second wiring 26B. The terminal unit 40 has multiple terminals and is configured to be electrically connectable to multiple wirings.

[0044] The control circuit 122 is a circuit that supplies control signals to the multiple photodiodes PD to control the detection operation. The multiple photodiodes PD output electrical signals corresponding to the light irradiated thereon as detection signals Vdet to the detection circuit 48. In this embodiment, the detection signals Vdet from the multiple photodiodes PD are output to the detection circuit 48 sequentially in a time-division manner. In other words, the multiple signal lines SL are electrically connected to the detection circuit 48 sequentially in a time-division manner. As a result, the detection device 1 detects information about the object to be detected based on the detection signals Vdet from the multiple photodiodes PD.

[0045] Fig. 7 is a plan view of a light-shielding layer of a detection device according to an embodiment. Fig. 8 is a cross-sectional schematic diagram taken along the line VIII-VIII' in Fig. 7. Fig. 9 is a plan view of the rear surface side of a light-shielding layer of a detection device according to an embodiment. Fig. 10 is a cross-sectional schematic diagram taken along the line XX' in Fig. 9.

[0046] 7, the detection device 1 has a light-shielding layer 50. The light-shielding layer 50 is a non-light-transmitting member that has a long side 501 and a short side 502, is formed in a deformable, flexible strip shape, and has a long side 501 and a short side 502. The light-shielding layer 50 is bonded to the substrate 21 and is housed in a ring-shaped housing.

[0047] A plurality of openings OP are provided in the light-shielding layer 50. The openings OP include a first opening OP1, a second opening OP2, and a third opening OP3.

[0048] 8 , the light-shielding layer 50 has a first surface 511 and a second surface 512 opposite to the first surface 511. A first opening OP1, a second opening OP2, and a third opening OP3 are provided so as to penetrate from the first surface 511 to the second surface 512.

[0049] 9 , an adhesive portion 55 is provided on the rear surface of the light-shielding layer 50 near the third opening OP3 on one end side of the short side 502 of the light-shielding layer 50. The adhesive portion 55 bonds the light-shielding layer 50 and the substrate 21. The adhesive portion 55 is made of the same material as the adhesive layer 240.

[0050] By providing only one adhesive surface, it is possible to prevent the adhesive surface from expanding and causing variations in thickness.

[0051] Also, as shown in Figures 9 and 10, the light-shielding layer 50 has convex portions on both ends of the long side 501 that extend along the longitudinal direction of the substrate 21 (first direction Dx) and protrude toward the substrate 21 (third direction Dz).

[0052] Fig. 11 is a schematic top view of the assembled light-shielding layer and light sensor. Fig. 12 is a schematic cross-sectional view showing the arrangement of the light source, light sensor, and light-shielding wall along the XII-XII' cross section shown in Fig. 11. Fig. 13 is a schematic cross-sectional view along the XIII-XIII' cross section shown in Fig. 11.

[0053] 11 , an adhesive portion 55 provided on the back surface of the light-shielding layer is joined to an adhesive layer 240 provided on the sensor side. The light-shielding layer 50 is disposed so as to cover the first optical sensor 10A and the second optical sensor 10B in a plan view.

[0054] 12 , a first light-shielding wall 51 surrounding the periphery of the light source 60 is provided in the first opening OP1. A second light-shielding wall 52 surrounding the periphery of the lower electrode 11 is provided in the second opening OP2. A third light-shielding wall 53 surrounding the periphery of the lower electrode 11 is provided in the third opening OP3. The height of the first light-shielding wall 51 is greater than the height of the light source 60. Light emitted from the light source 60 reaches a detection object such as a finger Fg through the first opening OP1. Light reflected by the detection object such as a finger Fg enters the first optical sensor 10A through the second opening OP2 and enters the second optical sensor 10B through the third opening OP3.

[0055] As a result, direct light irradiated from the light source 60 onto the first optical sensor 10A and the second optical sensor 10B is blocked by the first light-shielding wall 51, thereby improving detection accuracy.

[0056] The side surface of the first light-shielding wall 51 is shaped like a mortar, so that the light source light emitted from the light source 60 can easily reach the finger Fg even when reflected by the side surface of the first light-shielding wall 51.

[0057] The angle θ of the side surface of the first light-shielding wall 51 is equal to or greater than 65 degrees and equal to or less than 80 degrees.

[0058] This allows the light emitted from the light source 60 to be reflected by the first light-shielding wall 51 and easily focused on the finger Fg, thereby improving light efficiency.

[0059] The light-shielding layer 50 has light-shielding properties and has a glossy surface. The color of the light-shielding layer 50 is a natural color. The natural color is milky white, which is a color that does not easily transmit light, and the color changes little even when light from a light source is reflected. The material of the light-shielding layer 50 is, for example, urethane rubber. The color of the light-shielding layer 50 may be black as long as it has a glossy finish.

[0060] This allows the light emitted from the light source 60 to be more easily reflected by the first light-shielding wall 51, thereby improving the light efficiency.

[0061] 12 and 13 , the detection device 1 further includes a light-transmitting sealing layer 80 on the light-shielding layer 50. Each of the light source 60, the first optical sensor 10A, and the second optical sensor 10B is provided with a protrusion 81 that protrudes from the sealing layer 80 in a direction (third direction Dz) perpendicular to the substrate 21. The protrusion 81 has, for example, a dome shape.

[0062] This makes it easier to bring the protrusions 81 into close contact with the finger Fg, and therefore makes it easier for the light emitted from the light source 60 to penetrate into the finger Fg.

[0063] As shown in FIG. 13, the height of the convex portion 54 is equal to or greater than the thickness of the substrate 21 and the flexible printed circuit board 70 .

[0064] This blocks external light from entering the side surfaces of the convex portions 54, thereby improving the SNR.

[0065] 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.

[0066] REFERENCE SIGNS LIST 1 Detection 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 Substrate 21A One end 21B Other end 22 Notch portion 23 Connecting portion 24 Conductive material 25A First power supply electrode 25B Second power supply electrode 26A First wiring 26B Second wiring 26C Third wiring 27 Insulating layer 40 Terminal portion 48 Detection circuit 50 Light-shielding layer 51 First light-shielding wall 52 Second light-shielding wall 53 Third light-shielding wall 54 Convex portion 55 Adhesive portion 60 Light source 61 One end of the light source 62 Other end of the light source 70 Flexible printed circuit board 71 One end 72 Other end 73 First mounting area 74 Second mounting area 80 Sealing layer 81 Protrusion 90 Sealing film 91 Resin 122 Control circuit 123 Power supply circuit 150 Top surface 200 Housing 210 First housing 220 Second housing 240 Adhesive layer 501 Long side 502 Short side 511 First surface 512 Second surface OP Opening OP1 First opening OP2 Second opening OP3 Third opening

Claims

1. A substrate having a cutout portion between both ends in a first direction; a terminal portion provided at one end of the substrate in the first direction; a first optical sensor provided on the substrate between the cutout portion and the terminal portion; a second optical sensor provided on the substrate between the cutout portion and the other end of the substrate; and a light source arranged in the cutout portion of the substrate, 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 substrate in this order, and a light-shielding layer covering the first optical sensor and the second optical sensor in a planar view, the light-shielding layer having a plurality of openings, the openings having a first opening, a second opening, and a third opening, a first light-shielding wall surrounding the periphery of the light source is provided in the first opening, and a second light-shielding wall surrounding the periphery of the first optical sensor is provided in the second opening, The detection device, wherein a third light-shielding wall is provided in the third opening to surround the second optical sensor.

2. The detection device according to claim 1, wherein the side surface of the first light-shielding wall is shaped like a mortar.

3. The detection device according to claim 2, wherein the light-shielding layer has light-shielding properties and a glossy surface.

4. The detection device according to claim 3, wherein the angle of the side surface of the first light-shielding wall is between 65 degrees and 80 degrees.

5. The detection device according to claim 4, further comprising a light-transmitting sealing layer on the light-shielding layer, wherein each of the light source, the first optical sensor and the second optical sensor is provided with a protrusion that protrudes from the sealing layer in a direction perpendicular to the substrate.

6. The detection device according to claim 5, wherein the light-shielding layer has long sides and short sides, and an adhesive portion is provided on one end side of the short sides to bond the light-shielding layer to the substrate.

7. The detection device according to claim 6, wherein the light-shielding layer has protrusions on both ends of the long side that extend along the longitudinal direction of the substrate and protrude toward the substrate.

8. The detection device according to claim 7, wherein the substrate and the light-shielding layer are flexible and housed in a ring-shaped housing.

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