Detection device

Abstract

The present invention provides a detection device capable of improving light utilization efficiency of a light source. This detection device comprises a substrate, a light source disposed on the substrate, and a first optical sensor disposed on the substrate so as to be adjacent to the light source. The detection device has a reflection member disposed on the side, of the light source, opposite of that of the substrate and at a prescribed interval from the light source. A reflection surface of the reflection member is provided at a prescribed angle with respect to a virtual line connecting the center of gravity of the reflection member and the center of light emitted by a light-emitting element of the light source.

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 such an optical sensor, if the direct light from the light source to the object to be detected is biased directly above the light source, the reflected light received by the optical sensor will be limited, which may result in a decrease in the light utilization efficiency of the light source.

[0005] An object of the present invention is to provide a detection device that can improve the light utilization efficiency of a light source.

[0006] A detection device according to one aspect of the present invention comprises a substrate, a light source disposed on the substrate, and a first optical sensor disposed on the substrate adjacent to the light source, and further comprises a reflective member disposed on the opposite side of the light source from the substrate at a predetermined distance from the light source, the reflective surface of the reflective member being at a predetermined angle with respect to a virtual line connecting the light-emitting center of the light-emitting element of the light source and the center of gravity of the reflective member.

[0007] FIG. 1 is a schematic diagram illustrating an example of the external appearance of the 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 schematic cross-sectional view taken along the line II-II' in FIG. 1. FIG. 3 is a schematic cross-sectional view illustrating an example of the external appearance of a detection device according to a modified example of the first embodiment, when a human body is placed inside the detection device, as viewed from the side of the housing. FIG. 4 is a schematic cross-sectional view taken along the line IV-IV' in FIG. 3. FIG. 5 is a development view illustrating an example of the optical sensor of the detection device shown in FIG. 1. FIG. 6 is a schematic diagram illustrating an example of the configuration of the light source of the detection device shown in FIG. 2. FIG. 7 is a schematic top view illustrating an example of the configuration of the substrate shown in FIG. 5. FIG. 8 is a schematic cross-sectional view illustrating an example of the stacked configuration of the optical sensor taken along the line VIII-VIII' in FIG. 7. FIG. 9 is a schematic cross-sectional view illustrating an example of the stacked configuration of the optical sensor taken along the line IX-IX' in FIG. 7. FIG. 10 is a schematic top view illustrating an assembled state of the light-shielding wall, the reflective member, and the optical sensor. Fig. 11 is a cross-sectional schematic diagram showing the arrangement of the light source, optical sensor, light-shielding wall, etc. in the XI-XI' cross section shown in Fig. 10. Fig. 12 is a top view schematic diagram of the detection device according to embodiment 2 in a state in which the light-shielding wall, reflective member, and optical sensor are assembled. Fig. 13 is a cross-sectional schematic diagram showing the arrangement of the light source, optical sensor, light-shielding wall, etc. in the XIII-XIII' cross section shown in Fig. 12.

[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] 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.

[0011] The detection device 1 shown in FIG. 1 is a ring-shaped device that can be attached and detached to the human body, and is worn on a detection target Fg on the human body. The detection target Fg is, for example, a finger, and includes the thumb, index finger, middle finger, ring finger, little finger, etc. The human body is an authenticated person 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 worn on 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 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 first light-shielding wall 90, a second light-shielding wall 50, and a reflective member 91 (see FIGS. 10 and 11 ) described below. 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 attached to the detection subject Fg and is an attachment 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 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] (Modification of Embodiment 1) Fig. 3 is a schematic diagram showing an example of the appearance of a detection device according to a modification of Embodiment 1, when a human body is placed inside the detection device, as viewed from the side of the housing. Fig. 4 is a schematic cross-sectional view taken along the line IV-IV' shown in Fig. 3. The configuration of detection device 1a is the same as that of detection device 1, and therefore will not be described.

[0015] The detection device 1a according to a modified example of the first embodiment shown in Fig. 3 is a ring-shaped device that can be attached to and detached from the human body HB, and is worn on the arm of the human body HB and placed on a plane as shown in Fig. 4. The detection device 1a is, for example, a smartwatch, a wristwatch, a wristband, or the like. The human body HB is the body of the person to be authenticated whose identity is verified by the detection device 1, and includes the wrist, arm, leg, etc. The detection device 1 can detect biometric information related to the living body from the worn human body HB.

[0016] Fig. 5 is a development view showing an example of the optical sensor of the detection device shown in Fig. 1. Fig. 6 is a schematic diagram showing an example of the configuration of the light source of the detection device shown in Fig. 2. Fig. 7 is a schematic top view showing an example of the configuration of the substrate shown in Fig. 5. Fig. 8 is a schematic cross-sectional view showing an example of the layered configuration of the optical sensor in the VIII-VIII' cross section shown in Fig. 7. Fig. 9 is a schematic cross-sectional view showing an example of the layered configuration of the optical sensor in the IX-IX' cross section shown in Fig. 7.

[0017] As shown in FIG. 5 , 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.

[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] The detection device 1 further includes a substrate 21 and a terminal portion 40. The substrate 21 is an insulating substrate formed, for example, in a strip shape using a film-like resin or the like. The substrate 21 is deformable and has a first optical sensor 10A and a second optical sensor 10B mounted thereon. The substrate 21 is attached to a flexible printed circuit board 70, thereby positioning the first optical sensor 10A and the second optical sensor 10B on either side 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.

[0020] 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.

[0021] 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 detection object Fg to which the housing 200 is attached. For example, an inorganic LED (Light Emitting Diode) or an organic EL (Organic Light Emitting Diode) is used as the light source 60. In the first embodiment, the light source 60 is a single light source that irradiates light of a predetermined wavelength.

[0022] 6, the light source 60 is, for example, a PLCC (Plastic leaded chip carrier) type LED, and includes a frame 610, a lead frame 620, a sealing portion 630, and a light-emitting element 640.

[0023] The light source 60 has a structure in which a frame body 610 and a lead frame 620 are integrated together, and a light-transmitting resin that becomes a sealing portion 630 is injected into the frame body 610, and a light-emitting element 640 is mounted on the frame body 610. The light-emitting element 640 is surrounded by the wall of the frame body 610.

[0024] As a result, the light emitted from the light emitting element 640 is reflected by the frame body 610 , so that the light has a high directivity directly above the light source 60 and is easily collected on the reflecting member 91 .

[0025] Light emitted from the light source 60 is reflected by the surface of the object to be detected, such as the object 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 irregularities on the surface of the object Fg. Alternatively, the light emitted from the light source 60 may be reflected inside the object to be detected, such as the object Fg, or may pass through the object to be detected, and then enter 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 object to be detected, such as the pulse wave, pulse rate, and blood vessel image of a finger or palm. In other words, the detection device 1 may be configured as a fingerprint detection device that detects fingerprints, or a vein detection device that detects blood vessel patterns such as veins.

[0026] Each of the first optical sensor 10A and the second optical sensor 10B detects light emitted by the light source 60 and reflected by the detection object Fg, etc., as well as directly incident light. The first optical sensor 10A and the second optical sensor 10B are organic photodiodes (OPDs). The first optical sensor 10A is provided in the housing 200 so as to be adjacent to one terminal 61 of the light source 60 in the circumferential direction 200C of the housing 200. The second optical sensor 10B is provided in the housing 200 so as to be adjacent to the other terminal 62 of the light source 60 in the circumferential direction 200C of the housing 200.

[0027] As shown in FIG. 5 , the first optical sensor 10A and the second optical sensor 10B each have a photodiode PD (see FIG. 7 ), 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.

[0028] In addition, a second optical sensor 10B is provided adjacent to the light source 60 and arranged on a substrate 21 that does not overlap with the first optical sensor 10A, and the area of ​​the first optical sensor 10A and the area of ​​the second optical sensor 10B are arranged so as to sandwich the area in which the light source 60 is arranged.

[0029] Furthermore, the light source 60 is disposed inside the cutout portion 22 , and the first optical sensor 10A and the second optical sensor 10B are disposed on the substrate 21 on both sides of the cutout portion 22 .

[0030] 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.

[0031] As shown in FIG. 7 , 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.

[0032] 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 the power supply circuit 123 (see FIG. 5 ) 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 power from the power supply circuit 123 via the terminal 40.

[0033] 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.

[0034] 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.

[0035] The first and second power supply electrodes 25A and 25B receive power from the power supply circuit 123 via the terminals 40, and supply power to the upper electrodes 15A and 15B. In the example shown in Fig. 4, the first and second power supply electrodes 25A and 25B are formed in a substantially rectangular shape extending in the second direction Dy in a plan view, and have the same area (size).

[0036] 8, 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 900.

[0037] 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.

[0038] 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.

[0039] 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).

[0040] 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.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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 900 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.

[0045] The sealing film 900 is provided on the upper electrode 15. The sealing film 900 is light-transmitting and may be an inorganic film such as a silicon nitride film or an aluminum oxide film, or a resin film such as acrylic. The sealing film 900 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 900 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 900 to a portion of the terminal portion 40 with a resin 901.

[0046] As shown in FIG. 9 , 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).

[0047] 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 900 is provided on the upper electrode 15, the conductive material 24, etc., so that the photodiode PD is well sealed.

[0048] 7 , 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.

[0049] 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.

[0050] The terminal unit 40 is electrically connected to the flexible printed circuit board 70 (see FIG. 8 ). 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.

[0051] 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 Fg based on the detection signals Vdet from the multiple photodiodes PD.

[0052] Fig. 10 is a schematic top view of the assembled light-shielding wall, reflecting member, and light sensor. Fig. 11 is a schematic cross-sectional view showing the arrangement of the light source, light sensor, light-shielding wall, etc., along the XI-XI' cross section shown in Fig. 10.

[0053] 10 , the first light-shielding wall 90 is disposed to surround the light source 60 in a plan view. The detection device 1 also includes a second light-shielding wall 50 that surrounds the first optical sensor 10A and the second optical sensor 10B. The first light-shielding wall 90 and the second light-shielding wall 50 are non-transparent members.

[0054] 11 , the detection device 1 has a reflective member 91 disposed directly above the light source 60 at a predetermined distance from the light source 60. A reflective surface 910 of the reflective member 91 is provided at a predetermined angle α with respect to an imaginary line AX connecting the center of light emission of the light-emitting element 640 of the light source 60 and the center of gravity of the reflective member 91.

[0055] The shape of the reflective member 91 is, for example, a cone. The angle α is, for example, 30°±5°. The light-emitting center can be determined, for example, by turning on the light-emitting element 640 of the light source at maximum brightness and identifying the brightest location as viewed in the third direction Dz in Fig. 10. In Figs. 10 and 11, the center of gravity of the reflective member 91 is, for example, located on a line passing through the apex of the cone shape.

[0056] As a result, light emitted directly upward from the light source 60 is reflected by the reflecting member 91, making it easier to focus the light on the detection object Fg side, thereby improving light efficiency.

[0057] The reflective member 91 is surface-treated to make it more reflective. The color of the reflective member 91 is natural. The natural color is milky white, which is a color that does not easily transmit light, and the color change is small even when the light from the light source is reflected. The material of the reflective member 91 is, for example, urethane rubber. The color of the reflective member 91 may also be black as long as it has a glossy finish.

[0058] The device also includes a sealing layer 80 that covers the light source 60, the first optical sensor, and the second optical sensor, and the sealing layer 80 is disposed on the first light-shielding wall 90 and the second light-shielding wall 50. The sealing layer 80 has a first surface 801 and a second surface 802 opposite to the first surface 801, and a reflective member 91 is provided on the first surface 801 that faces the light source 60.

[0059] The side surface of the first light-shielding wall 90 is shaped like a mortar.

[0060] This makes it easier for the light emitted from the light source 60 to reach the detection object Fg even if it is reflected by the side surface of the first light-shielding wall 51.

[0061] The angle θ of the side surface of the first light-shielding wall 90 is equal to or greater than 65 degrees and equal to or less than 80 degrees.

[0062] This allows the light emitted from the light source 60 to be reflected by the reflecting member 91 and easily focused on the detection object Fg, thereby improving the light efficiency.

[0063] 11 , the second surface 802 is provided with optically transparent protrusions 81 at positions corresponding to the light source 60, the first optical sensor 10A, and the second optical sensor 10B in a plan view, the protrusions 81 protruding from the sealing layer 80 in a direction perpendicular to the substrate 21 (third direction Dz). The protrusions 81 are, for example, dome-shaped.

[0064] This makes it easier to bring the protrusions 81 into close contact with the detection object Fg, and therefore makes it easier for the light emitted from the light source 60 to penetrate into the detection object Fg.

[0065] (Embodiment 2) Fig. 12 is a schematic top view of a detection device according to embodiment 2, in which a light-shielding wall, a reflecting member, and an optical sensor are assembled. Fig. 13 is a schematic cross-sectional view showing the arrangement of the light source, the optical sensor, the light-shielding wall, etc., along the XIII-XIII' cross section shown in Fig. 12. In the following description, the same components as those described in the above-mentioned embodiment are designated by the same reference numerals, and redundant description will be omitted.

[0066] 12 , the light source 60 of the detection device 1A according to the second embodiment includes a first light source 601, a second light source 602, and a third light source 603. The first light source 601, the second light source 602, and the third light source 603 emit near-infrared light, red light, and green light, respectively.

[0067] As shown in FIG. 12, in a plan view, the first light-shielding wall 90A is disposed so as to surround the light source 60 in the first direction Dx.

[0068] 12 and 13 , the detection device 1A has a reflective member 91A disposed at a predetermined distance from the light source 60 at a position directly above the light source 60 on the side opposite the substrate 21 of the light source 60. A reflective surface 910 of the reflective member 91A is formed at a predetermined angle β with respect to an imaginary line AY connecting the center of light emission of the light-emitting element 640 of the light source 60 and the center of gravity of the reflective member 91.

[0069] The reflecting member 91A has a triangular prism shape. The angle β is, for example, 45°±5°. The inclined surface, which is the reflecting surface 910 of the reflecting member 91A, is inclined toward the first optical sensor 10A or the second optical sensor 10B.

[0070] As a result, light emitted directly upward from the light source 60 is reflected by the reflecting member 91A, making it easier to focus the light on the detection object Fg side, thereby improving light efficiency.

[0071] 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.

[0072] REFERENCE SIGNS LIST 1, 1a, 1A 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 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 Second light-shielding wall 60 Light source 61 One terminal portion of light source 62 Other terminal portion of 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 portion 90, 90A First light-shielding wall 91, 91A Reflecting member 150 Upper surface 200 Housing 210 First housing 220 Second housing 601 First light source 602 Second light source 603 Third light source 610 Frame 620 Lead frame 630 Sealing portion 640 Light emitting element 801 First surface 802 Second surface 900 Sealing film 901 Resin 910 Reflecting surface AX, AY Virtual line

Claims

1. A detection device comprising: a substrate; a light source arranged on said substrate; and a first optical sensor arranged on said substrate adjacent to said light source; wherein a reflective member is arranged on the opposite side of said light source from said substrate at a predetermined distance from said light source, and the reflective surface of said reflective member is at a predetermined angle with respect to an imaginary line connecting the light-emitting center of the light-emitting element of said light source and the center of gravity of said reflective member.

2. The detection device according to claim 1, wherein the light source is a PLCC type LED.

3. The detection device according to claim 2, further comprising a second optical sensor arranged on the substrate adjacent to the light source and not overlapping with the first optical sensor, the region of the first optical sensor and the region of the second optical sensor being arranged so as to sandwich the region in which the light source is arranged.

4. The detection device according to claim 3, wherein the substrate has a cutout portion between both ends in the first direction, the light source is disposed inside the cutout portion, and the first optical sensor and the second optical sensor are disposed on the substrate on both sides of the cutout portion.

5. The detection device according to claim 4, wherein the reflecting member has a conical shape.

6. The detection device according to claim 4, wherein the reflecting member is shaped like a triangular prism, and the inclined surface of the reflecting member is inclined toward the first optical sensor or the second optical sensor.

7. The detection device according to claim 5, further comprising a sealing layer that covers the light source, the first optical sensor, and the second optical sensor, the sealing layer having a first surface and a second surface opposite to the first surface, and the reflective member being provided on the first surface that faces the light source.

8. The detection device according to claim 6, further comprising a first light-shielding wall surrounding the periphery of the light source, the side surface of the first light-shielding wall being shaped like a mortar.

9. The detection device according to claim 7, wherein the angle of the side surface of the first light-shielding wall is between 65 degrees and 80 degrees.

10. The detection device according to claim 8, further comprising a second light-shielding wall surrounding each of the light source, the first optical sensor, and the second optical sensor in a plan view, and the sealing layer is disposed on the first light-shielding wall and the second light-shielding wall.

11. The detection device according to claim 9, wherein the second surface is provided with optically transparent protrusions at positions corresponding to the light source, the first optical sensor, and the second optical sensor in a plan view.

12. The detection device according to claim 10, wherein the first optical sensor and the second optical sensor are OPDs (organic photodiodes).

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