Method for manufacturing detection device

Abstract

Provided is a method for manufacturing a detection device that has: a ring-shaped housing; a sensor member stored inside the housing and in which a flexible substrate, a sensor substrate, an organic optical sensor layer, and a sealing layer are stacked in this order; and a light source disposed inside the housing. The method includes: a first bending step of bending a portion of the sensor member corresponding to a curved part of the sensor substrate at a first angle which is smaller than a buckling limit; a flattening step of returning the sensor member to a flat state, after the first bending step; a second bending step of bending the portion of the sensor member corresponding to the curved part of the sensor substrate at a second angle larger than the first angle, after the flattening step; and a storage step of storing the sensor member in the housing, after the second bending step.

Description

Method for manufacturing a detection device

[0001] The present invention relates to a method for manufacturing 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 cause damage to the sensor substrate, such as cracking or buckling, or wire breakage.

[0005] An object of the present invention is to provide a method for manufacturing a detection device that can suppress damage to a sensor substrate.

[0006] A method for manufacturing a detection device according to one aspect of the present disclosure is a method for manufacturing a detection device having a ring-shaped housing, a sensor member stored inside the housing and including a flexible substrate, a sensor substrate, an organic photosensor layer, and a sealing layer stacked in this order, and a light source disposed inside the housing, wherein the organic photosensor layer includes a first photosensor and a second photosensor disposed spaced apart from the first photosensor, and the sensor substrate has a first portion where the first photosensor is disposed, a second portion where the second photosensor is disposed, and a third portion having a width narrower than the first portion and the second portion and connecting the first portion and the second portion, and each of the connection points between the second part and the third part has a curved part, and the light source is disposed in a region between the first part and the second part that overlaps with a cutout part corresponding to the third part, and the method includes a first bending step of bending a part of the sensor member corresponding to the curved part of the sensor substrate at a first angle smaller than a buckling limit, a flattening step of returning the sensor member to a flat state after the first bending step, a second bending step of bending a part of the sensor member corresponding to the curved part of the sensor substrate at a second angle larger than the first angle after the flattening step, and a storing step of storing the sensor member in the housing after the second bending step.

[0007] FIG. 1 is a schematic diagram illustrating 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 cross-sectional view taken along line II-II' in FIG. 1. FIG. 3 is a development view illustrating an example of a development of a flexible substrate of the detection device according to an embodiment. FIG. 4 is a cross-sectional view illustrating a layered configuration of a sensor member according to the present embodiment. FIG. 5 is a plan view illustrating an example of the configuration of the sensor substrate shown in FIG. 3. FIG. 6 is a cross-sectional view taken along line VI-VI' in FIG. 5. FIG. 7 is a cross-sectional view taken along line VII-VII' in FIG. 5. FIG. 8 is an explanatory diagram illustrating a manufacturing method of a detection device according to an embodiment. FIG. 9 is a graph schematically illustrating the relationship between the radius of curvature and the angle when the sensor substrate is bent. FIG. 10 is an explanatory diagram illustrating the radius of curvature and the angle when the sensor substrate is bent. FIG. 11 is a schematic diagram illustrating the bending process of the sensor member in FIG. 8. FIG. 12 is a graph schematically illustrating the relationship between strain and stress in the sensor substrate.

[0008] 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.

[0009] 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.

[0010] 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 a housing. FIG. 2 is a cross-sectional view taken along line II-II′ of FIG. 1.

[0011] As shown in FIG. 1 , the detection device 1 according to the 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.

[0012] 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.

[0013] 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 substrate 70. The detection device 1 includes a battery (not shown) inside the housing 200 and operates on power from the battery.

[0014] 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.

[0015] 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.

[0016] 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 substrate 70 mounted with the light source 60, the first optical sensor 10A, the second optical sensor 10B, etc., inside the first housing 210. The flexible substrate 70 is accommodated inside the housing 200 by, for example, bending the flexible substrate 70 at predetermined angles at multiple locations so as to fit the ring-shaped housing 200, and filling the surrounding area with a filler to form the housing 200.

[0017] The flexible substrate 70 has flat surfaces in the region where the light source 60 is provided, the region where the first optical sensor 10A is provided, and the region where the second optical sensor 10B is provided. The flexible substrate 70 is bent at a predetermined angle in the region between the light source 60 and the first optical sensor 10A, and is bent at a predetermined angle in the region between the light source 60 and the second optical sensor 10B. It is sufficient that at least the region where the light source 60 is provided of the flexible substrate 70 is flat, and at least one of the region where the first optical sensor 10A and the region where the second optical sensor 10B are provided may be curved along the housing 200.

[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] In this embodiment, a member housed inside the housing 200 and including the flexible substrate 70, the first optical sensor 10A, the second optical sensor 10B, the light source 60, etc. will be referred to as the sensor member 100. The detailed configuration of the sensor member 100 will be described below with reference to FIGS. 3 to 7.

[0023] 3 is a development view showing an example of development of the flexible substrate of the detection device according to the embodiment. As shown in FIG. 3, the flexible substrate 70 is formed in a deformable band shape and has one end 71 and the other end 72 along the circumferential direction 200C. The flexible substrate 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.

[0024] The sensor substrate 21 is mounted on the flexible substrate 70 so as to straddle the vicinity of the light source 60 in the first mounting region 73. The first optical sensor 10A, the second optical sensor 10B, etc. are mounted on the sensor substrate 21. The sensor substrate 21 is an insulating substrate, and is formed, for example, in a strip shape using a film-like resin or the like, making it a deformable substrate. The sensor substrate 21 is provided inside the housing 200 and is bent to fit the shape of the housing 200. The flexible substrate 70 electrically connects the first optical sensor 10A and the second optical sensor 10B on the sensor substrate 21, the light source 60, and the control circuit 51.

[0025] 4 is a cross-sectional view showing the layered structure of the sensor member according to this embodiment. As shown in FIG. 4 , the sensor member 100 is formed by layering a flexible substrate 70, an adhesive layer 80, a sensor substrate 21, an organic photosensor layer 10L, an adhesive layer 81, and a sealing film 90 in this order. The organic photosensor layer 10L is an OPD layer including the first photosensor 10A and the second photosensor 10B disposed spaced apart from the first photosensor 10A. The adhesive layers 80 and 81 are translucent functional films having double-sided adhesive properties, such as optical clear adhesive (OCA).

[0026] The sealing film 90 may be an inorganic film such as a silicon nitride film or an aluminum oxide film, or a resin film such as an acrylic film. 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 organic photosensor layer 10L (the first photosensor 10A and the second photosensor 10B) and can prevent moisture from entering from the upper surface.

[0027] 2 , the flexible substrate 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 substrate 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 substrate 70 and the light that has passed through the flexible substrate 70 is emitted toward the outside of the housing 200.

[0028] Fig. 5 is a plan view showing an example of the configuration of the sensor substrate shown in Fig. 3. Fig. 5 shows a plan view of the sensor substrate 21 when developed into a flat plate.

[0029] 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.

[0030] As shown in FIG. 5 , the sensor board 21 has a cutout 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. A plurality of first optical sensors 10A are mounted on one end 21A of the sensor board 21, and a plurality of second optical sensors 10B are mounted on the other end 21B of the sensor board 21, sandwiching the cutout 22. In other words, the cutout 22 is located between the first optical sensors 10A and the second optical sensors 10B in the first direction Dx. The terminal 40 is provided at one end 21A of the sensor board 21 in the longitudinal direction. The terminal 40 supplies power from a power supply circuit 52 (see FIG. 3 ) to the first optical sensors 10A and the second optical sensors 10B.

[0031] The sensor substrate 21 has a first portion 21a where the first optical sensor 10A is arranged, a second portion 21b where the second optical sensor 10B is arranged, and a third portion 21c that connects the first portion 21a and the second portion 21b. The first portion 21a where the first optical sensor 10A is provided, the second portion 21b where the second optical sensor 10B is provided, and the third portion 21c of the sensor substrate 21 are integrally formed.

[0032] The width of the third portion 21c in the second direction Dy is smaller than the widths of the first portion 21a and the second portion 21b in the second direction Dy. The notch 22 is provided at a position corresponding to the third portion 21c.

[0033] 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.

[0034] 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 and have curvature. The curved portion 22d is provided at the connection point between the first portion 21a and the third portion 21c of the sensor substrate 21. The curved portion 22c is provided at the connection point between the second portion 21b and the third portion 21c of the sensor substrate 21.

[0035] More specifically, the straight 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 portion 22c. The straight portion 22f extends in the first direction Dx, with one end connected to the curved portion 22c and the other end connected to the curved portion 22d. The straight portion 22g extends in the second direction Dy, with one end connected to the curved portion 22d and the other end connected to the second side S2 of the sensor substrate 21.

[0036] In the sensor substrate 21, stress concentration is likely to occur at the corners of the cutout portion 22, i.e., the connection between the first portion 21a and the third portion 21c and the connection between the second portion 21b and the third portion 21c. In this embodiment, arc-shaped curved portions 22c and 22d having curvature are provided at the corners of the cutout portion 22 where stress concentration is likely to occur. This allows stress to be dispersed by the curved portions 22c and 22d, thereby effectively suppressing the generation of stress in the sensor substrate 21. Furthermore, even when the sensor substrate 21 is bent at a predetermined angle to follow the shape of the housing 200, it is possible to suppress the generation of local stress concentration in the sensor substrate 21.

[0037] The light source 60 is disposed in an area overlapping the cutout portion 22. The length 22a of the cutout portion 22 in the first direction Dx is longer than the length of the light source 60 in the first direction Dx. The length 22a of the cutout portion 22 in the second direction Dy is longer than the length of the light source 60 in the second direction Dy. This allows the cutout portion 22 of the sensor substrate 21 to secure space for disposing the light source 60.

[0038] Next, the configurations of the first optical sensor 10A and the second optical sensor 10B will be described with reference to Figures 5 to 7. Figure 6 is a cross-sectional view taken along line VI-VI' in Figure 5. Figure 7 is a cross-sectional view taken along line VII-VII' in Figure 5.

[0039] 5, 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.

[0040] 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.

[0041] 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 therebetween.

[0042] 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 passes through a region on the second side S2 of the sensor substrate 21 to be connected to the terminal 40. The third wiring 26C connected to the lower electrode 11 of the second optical sensor 10B passes through a region on the first side S1 of the sensor substrate 21 and the third portion 31c to be connected to the terminal 40. 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 substrate 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.

[0043] 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. 5, 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).

[0044] As shown in FIG. 6, the photodiode PD constituting the first optical sensor 10A is provided on the first portion 21a of the sensor substrate 21 via an insulating layer 27.

[0045] 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. 5 ). 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.

[0046] 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.

[0047] The lower electrode 11 is made of a light-transmitting conductive material such as ITO (Indium Tin Oxide).

[0048] 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 ６１Phenyl 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.

[0049] 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.

[0050] 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).

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 7 , the two lower electrodes 11 of the second optical sensor 10B are provided in a second portion 21b of the sensor 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 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.

[0055] 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.

[0056] In this embodiment, as described above, the sensor substrate 21 is provided with the cutout portion 22, and the arc-shaped curved portions 22c and 22d are provided at the corners of the cutout portion 22. 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 third portion 21c and damage to the photodiode PD.

[0057] Note that the configurations shown in FIGS. 1 to 7 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. 5. For example, the radius of curvature (curvature) of the curved portions 22c and 22d of the cutout portion 22 is merely an example and can be modified as appropriate. Furthermore, while the detection device 1 has four photodiodes PD, it may have three or fewer or five or more. Furthermore, the housing 200 shown in FIG. 2 is ring-shaped with a curvature along its entire circumference, but is not limited thereto. The housing 200 may have a flat region in a portion of its circumference, for example, in the portion where the light source 60 is disposed.

[0058] (Method of Manufacturing Detection Device) Next, a method of manufacturing the detection device 1 will be described with reference to Fig. 8 to Fig. 12. Fig. 8 is an explanatory diagram for explaining a method of manufacturing a detection device according to an embodiment. Note that each of Fig. 8 diagrams schematically shows the cross-sectional configurations of the flexible substrate 70, the sensor substrate 21, and the light source 60 of the sensor member 100, and omits the configurations of the first optical sensor 10A, the second optical sensor 10B, various wirings, etc.

[0059] 8, first, the flexible substrate 70 and the sensor substrate 21 are laminated in a flat state to form the sensor member 100 (step ST1). More specifically, the sensor member 100 is formed by laminating the flexible substrate 70, the adhesive layer 80, the sensor substrate 21, the organic photosensor layer 10L, the adhesive layer 81, and the sealing film 90 in this order (see FIG. 4). The light source 60 is also disposed on the flexible substrate 70.

[0060] Next, in a first bending step, the portions of the sensor member 100 corresponding to the curved portions 22c and 22d (see FIG. 5) of the sensor substrate 21 are bent at a first angle θ1 smaller than the buckling limit (step ST2).

[0061] Here, we will explain how to set the first angle θ1 of the sensor substrate 21, and the definitions of the radius of curvature and angle of the sensor substrate 21. Fig. 9 is a graph schematically showing the relationship between the radius of curvature and the angle when the sensor substrate is bent.

[0062] The horizontal axis of the graph shown in Fig. 9 represents the radius of curvature of the sensor substrate 21, and the vertical axis represents the angle when the sensor substrate 21 is bent. The relationship between the radius of curvature and the angle of the sensor substrate 21 shown in Fig. 9 is data obtained by previously conducting a bending test on the sensor substrate 21. In Fig. 9, the "OK" region represents the range of the radius of curvature and the angle in which cracks, buckling, wiring breaks, etc. occur in the sensor substrate 21. The "NG" region represents the range of the radius of curvature and the angle in which cracks, buckling, wiring breaks, etc. occur in the sensor substrate 21.

[0063] The first angle θ1 in step ST2 and the second angle θ2 described later are set in advance at angles that will not cause defects such as buckling of the sensor substrate 21, based on the relationship between the radius of curvature and the angle of the sensor substrate shown in Fig. 9 and the shape (curvature) of the housing 200 in which the sensor member 100 is stored. The "buckling limit" in step ST2 described above indicates the boundary between the "OK" region and the "NG" region in Fig. 9. That is, the first angle θ1 and the second angle θ2 described later are set in the "OK" region in the relationship between the radius of curvature and the angle shown in Fig. 9, i.e., at angles smaller than the buckling limit.

[0064] 10 is an explanatory diagram for explaining the radius of curvature and the angle when the sensor substrate is bent. As shown in Fig. 10, the radius of curvature R and the angle (first angle θ1, second angle θ2) of the sensor member 100 are defined based on the sensor substrate 21 located on the inner peripheral surface side of the cross-sectional shape of the sensor member 100.

[0065] 10 , the angle of the sensor member 100 (sensor board 21) is the angle formed between an extension of the straight portion of the second portion 21b and an extension of the straight portion of the third portion 21c of the sensor board 21. The radius of curvature R of the sensor member 100 (sensor board 21) is the radius of curvature of the curved portion that curves in an arc shape between the straight portion of the third portion 21c of the sensor board 21 and the straight portion of the second portion 21b.

[0066] 10 illustrates the connection point between the second portion 21b and the third portion 21c of the sensor substrate 21, the definitions of the radius of curvature and angle of the connection point between the first portion 21a and the third portion 21c are the same. Preferably, the radius of curvature and angle of the connection point between the second portion 21b and the third portion 21c of the sensor substrate 21 are equal to the radius of curvature and angle of the connection point between the first portion 21a and the third portion 21c. However, the radius of curvature and angle of the connection point between the second portion 21b and the third portion 21c of the sensor substrate 21 may be different from the radius of curvature and angle of the connection point between the first portion 21a and the third portion 21c.

[0067] FIG. 11 is a schematic diagram illustrating the bending process of the sensor member in FIG. 8 . As shown in FIG. 11 , the first bending process is performed using a support member 111 and a cylindrical member 110 having a predetermined radius of curvature. One end 71 of the flexible substrate 70 (corresponding to the first portion 21 a and the third portion 21 c of the sensor substrate 21) is fixed to the base portion 111 a of the support member 111. The other end 72 of the flexible substrate 70 (corresponding to the second portion 21 b of the sensor substrate 21) is fixed to the wall portion 111 b of the support member 111. The cylindrical member 110 is then positioned so as to extend along the second direction Dy (see FIG. 5 ) at a position overlapping the curved portion 22 c of the sensor substrate 21. The portion of the sensor member 100 corresponding to the curved portion 22 c of the sensor substrate 21 is bent along the outer periphery of the cylindrical member 110. As a result, the connection portion between the second portion 21b and the third portion 21c of the sensor substrate 21 is bent at a predetermined first angle θ1.

[0068] Figure 11 shows the first bending process of the connection point between the second part 21b and the third part 21c of the sensor substrate 21, but the first bending process of the connection point between the first part 21a and the third part 21c is also performed in the same way using a support member 111 and a cylindrical member 110 having a predetermined radius of curvature.

[0069] Returning to FIG. 8, after the first bending step (step ST2), the sensor member 100 (flexible substrate 70 and sensor substrate 21) is returned to a flat state in a flattening step (step ST3).

[0070] After the flattening step, in a second bending step, the portions of the sensor member 100 corresponding to the curved portions 22c and 22d of the sensor substrate 21 are bent at a second angle θ2 larger than the first angle θ1 (step ST4).

[0071] In the second bending process shown in step ST4, a support member 111 and a columnar member 110 having a predetermined radius of curvature are used, as in Fig. 11. However, in the second bending process, the flexible substrate 70 is bent at a second angle θ2 that is larger than the first angle θ1, as compared to the first bending process shown in Fig. 11. Note that any method may be used to vary the bending angle. For example, the height of the wall portion 111b may be increased, or another member (wall portion) may be added to one end 71 of the flexible substrate 70.

[0072] After the second bending step, in the storing step, the sensor member 100 is stored in the ring-shaped housing 200 with the portions of the sensor board 21 corresponding to the curved portions 22c and 22d bent (step ST5).

[0073] Fig. 12 is a graph schematically showing the relationship between the strain and stress of the sensor substrate 21. The horizontal axis of the graph shown in Fig. 12 represents the strain of the sensor substrate 21, and the vertical axis represents the stress of the sensor substrate 21. The graph shown in Fig. 12 is merely a schematic diagram for explaining the effect of the manufacturing method of the detection device 1, and differs from the actual relationship between the strain and stress of the sensor substrate 21.

[0074] 12 , in the first bending process (step ST2), as the distortion of the sensor substrate 21 increases (the angle of the sensor substrate 21 increases), the stress increases, as indicated by arrow 121. When the stress of the sensor substrate 21 exceeds the yield point in the first bending process, the sensor substrate 21 undergoes plastic deformation, and the slope indicating the relationship between distortion and stress decreases, as indicated by arrow 122.

[0075] The first angle θ1 is set in a region where the sensor substrate 21 does not buckle, so the stress σ when bent at the first angle θ1 is ｘ is smaller than (σ a <σ<σ x ).

[0076] When the sensor substrate 21 is planarized in the planarization step (step ST3), the sensor substrate 21 is unloaded, and the stress σ approaches 0 as indicated by the arrow 123 .

[0077] After the flattening process, in the second bending process (step ST4), as shown by arrow 124, the stress increases as the distortion of the sensor substrate 21 increases (the angle of the sensor substrate 21 increases). In this embodiment, the kinematic hardening law is applied, so the yield point in the second bending process is higher than the yield point in the first bending process. Once the yield point in the second bending process is exceeded, the sensor substrate 21 undergoes plastic deformation, and the slope of the relationship between distortion and stress decreases, as shown by arrow 125.

[0078] As shown in FIG. 12, after the first bending step, the flattening step, and the second bending step, the stress σ at which the sensor substrate 21 breaks is ｘ The strain of the sensor substrate 21 corresponding to this is defined as ε2. In contrast, if the sensor substrate 21 is bent in a single bending process (see arrow 126), the stress σ at which the sensor substrate 21 breaks is defined as ｘ In this embodiment, since the first bending process, the flattening process, and the second bending process are performed, the strain ε2 when the sensor substrate 21 breaks is larger than the strain ε1 when the sensor substrate 21 breaks in a single bending process.

[0079] Therefore, the manufacturing method of the detection device 1 of this embodiment includes the first bending step, the flattening step, and the second bending step, and therefore, even if the sensor substrate 21 is deformed to the second angle θ2 that is larger than the first angle θ1, it is possible to suppress damage such as cracking and buckling of the sensor substrate 21. Furthermore, the manufacturing method of the detection device 1 of this embodiment includes the first bending step, the flattening step, and the second bending step, and therefore, even if the sensor substrate 21 is provided with the cutout portion 22 and is bent at positions corresponding to the corners of the cutout portion 22 where stress concentration is likely to occur (the connection portion between the first portion 21 a and the third portion 21 c and the connection portion between the second portion 21 b and the third portion 21 c), it is possible to suppress damage such as cracking and buckling of the sensor substrate 21.

[0080] 8, an example in which the sensor substrate 21 is bent at the first angle θ1 and the second angle θ2 has been described, but the present invention is not limited to this. In step ST2 shown in FIG. 8, the sensor substrate 21 may be bent at a first radius of curvature R1, and in step ST4, the sensor substrate 21 may be bent at a second radius of curvature R2 that is smaller than the first radius of curvature R1.

[0081] 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.

[0082] REFERENCE SIGNS LIST 1 Detector 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 21a First portion 21b Second portion 21c Third portion 22 Notch portion 22c, 22d Curved portion 60 Light source 70 Flexible substrate 80, 81 Adhesive layer 90 Sealing film 100 Sensor member 200 Housing 210 First housing 220 Second housing PD Photodiode

Claims

1. A method for manufacturing a detection device having: a ring-shaped housing; a sensor member stored inside the housing and formed by stacking a flexible substrate, a sensor substrate, an organic photosensor layer, and a sealing layer in this order; and a light source arranged inside the housing, wherein the organic photosensor layer includes a first photosensor and a second photosensor arranged spaced apart from the first photosensor; the sensor substrate has a first portion where the first photosensor is arranged, a second portion where the second photosensor is arranged, and a third portion having a width narrower than the first and second portions and connecting the first and second portions; the connection point between the first and third portions and the connection point between the second and third portions each have a curved portion; the light source is arranged in a region between the first and second portions that overlaps with a cutout portion corresponding to the third portion; a first bending step of bending a portion of the sensor member corresponding to the curved portion of the sensor substrate at a first angle smaller than a buckling limit; and a flattening step of returning the sensor member to a flat state after the first bending step. a second bending step of bending, after the flattening step, a portion of the sensor member corresponding to the curved portion of the sensor substrate at a second angle larger than the first angle; and a storing step of storing the sensor member in the housing after the second bending step.

2. A method for manufacturing a detection device as described in claim 1, wherein in the first bending process and the second bending process, a cylindrical member having a predetermined radius of curvature is used, and the portion of the sensor member corresponding to the curved portion of the sensor substrate is bent along the outer periphery of the cylindrical member.

3. A method for manufacturing a detection device as described in claim 1, wherein the first angle is determined based on the relationship between the radius of curvature and the angle when the sensor substrate is bent along the circumference of a cylindrical member, and the curvature of the housing.

4. The method for manufacturing a 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 this order.

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