Detection device

Abstract

This detection device has: an optical sensor including a sensor substrate and a plurality of light detection elements that are disposed in a planar manner on the sensor substrate; and a light source including a light source substrate and a plurality of light-emitting elements that are disposed in a planar manner on the light source substrate, the light source being disposed to face the optical sensor. The sensor substrate and the light source substrate are each a flexible substrate. The sensor substrate and the light source substrate are connected in a bag-like shape having an opening along one side. The detection device also has an external connection terminal provided on at least one of the optical sensor and 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). 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, multiple photodiodes mounted on the sensor substrate, and a light source that irradiates the multiple photodiodes with light.

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

[0004] In a detection device using such an optical sensor, the sensor output from the multiple photodiodes may vary depending on the distance between the multiple photodiodes and the light source, the state of the object to be detected such as a finger, etc. This may result in a decrease in the accuracy of detecting the object to be detected.

[0005] An object of the present invention is to provide a detection device that can improve detection accuracy.

[0006] A detection device of one aspect of the present disclosure includes a sensor substrate, an optical sensor including a plurality of light detection elements arranged in a plane on the sensor substrate, a light source substrate, and a plurality of light-emitting elements arranged in a plane on the light source substrate, and a light source arranged opposite the optical sensor, wherein the sensor substrate and the light source substrate are each flexible substrates, and the sensor substrate and the light source substrate are connected in a bag-like shape having an opening along one side.

[0007] FIG. 1 is a schematic diagram showing an example of the appearance of a detection device according to the first embodiment with a finger placed inside. FIG. 2 is a cross-sectional view taken along line II-II' of FIG. 1. FIG. 3 is a development showing an example of a sensor substrate and a light source substrate of the detection device according to the first embodiment. FIG. 4 is a plan view showing an example of the configuration of a scanning circuit, external connection terminals, and wiring of the detection device according to the first embodiment. FIG. 5 is a block diagram showing an example of the configuration of a control circuit. FIG. 6 is a circuit diagram showing multiple sensor pixels of an optical sensor. FIG. 7 is a circuit diagram showing a light source drive circuit. FIG. 8 is a timing chart showing an example of the operation of the detection device according to the first embodiment. FIG. 9 is a flowchart showing an example of the operation of the detection device according to the first embodiment. FIG. 10 is a flowchart showing an example of a method of generating sensor correction data. FIG. 11 is an explanatory diagram illustrating step ST11 in FIG. 10. FIG. 12 is an explanatory diagram illustrating a method of generating sensor correction data in FIG. 10. FIG. 13 is an explanatory diagram illustrating an example of a method of detecting a finger region in FIG. 9. FIG. 14 is a development showing an example of a sensor substrate and a light source substrate of a detection device according to a first modified example. Fig. 15 is a development view showing an example of development of a sensor substrate and a light source substrate of a detection device according to a second embodiment. Fig. 16 is a cross-sectional view of a detection device according to a second embodiment. Fig. 17 is a plan view showing an example of a configuration of a scanning circuit, external connection terminals, and wiring of a detection device according to a second embodiment. Fig. 18 is a plan view showing an example of a configuration of a scanning circuit, external connection terminals, and wiring of a detection device according to a third embodiment. Fig. 19 is a circuit diagram showing a light source according to a third embodiment. Fig. 20 is a timing chart showing an example of operation of a detection device according to a third embodiment.

[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] First Embodiment Fig. 1 is a schematic diagram showing an example of the appearance of a detection device according to a first embodiment in a state where a finger is placed inside the detection device. 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 first embodiment is a bag-like device that has an opening OP on one side and can be attached to and detached from the human body. The detection device 1 is attached to, 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 detection device 1 can detect biological information about a living body from the finger Fg on which it is attached. The finger Fg is an example of a measurement target.

[0012] The detection device 1 includes an optical sensor 10 and a light source 20 facing the optical sensor 10. The detection device 1 is substantially rectangular and has a first side S1, a second side S2 opposite the first side S1, and a third side S3 and a fourth side S4 between the first side S1 and the second side S2. An opening OP is formed between the optical sensor 10 and the light source 20 along the first side S1. The optical sensor 10 and the light source 20 are also formed into a bag shape by bonding together edges along the second side S2, the third side S3, and the fourth side S4.

[0013] 2 , the optical sensor 10 includes a sensor substrate 11, a plurality of light detection elements 12 arranged in a planar manner on the sensor substrate 11, and a sealing film 13. The light source 20 includes a light source substrate 21, a plurality of light emitting elements 22 arranged in a planar manner on the light source substrate 21, and a protective film 23. The light source 20 is arranged corresponding to the optical sensor 10. The optical sensor 10 of this embodiment is a planar optical sensor, and the light source 20 is a planar light source.

[0014] The sensor substrate 11 and the light source substrate 21 are disposed opposite each other. A plurality of light detection elements 12 are provided on the surface of the sensor substrate 11 facing the light source substrate 21. A plurality of light-emitting elements 22 are provided on the surface of the light source substrate 21 facing the sensor substrate 11. The sensor substrate 11 and the light source substrate 21 are each a flexible substrate formed from a sheet-like resin material. The sensor substrate 11 and the light source substrate 21 are configured to be deformable according to the shape of a detection object such as a finger Fg.

[0015] The light detection elements 12 output electrical signals corresponding to the light irradiated thereon. More specifically, the light detection elements 12 are photodiodes, and are configured, for example, as PIN (Positive Intrinsic Negative) photodiodes or OPDs (Organic Photodiodes) using organic semiconductors.

[0016] The sealing film 13 is provided on the sensor substrate 11 to cover the multiple light detection elements 12. An inorganic film such as a silicon nitride film or an aluminum oxide film, or a resin film such as an acrylic film is used as the sealing film 13. The sealing film 13 is not limited to a single layer, but may be a laminated film of two or more layers that combines the inorganic film and the resin film.

[0017] The plurality of light-emitting elements 22 are disposed opposite the plurality of light-detecting elements 12. The plurality of light-emitting elements 22 may be, for example, inorganic light-emitting diodes (LEDs) or organic light-emitting diodes (OLEDs). The plurality of light-emitting elements 22 emit light of a predetermined wavelength. In this embodiment, the plurality of light-emitting elements 22 include a plurality of first light-emitting elements 22IR and a plurality of second light-emitting elements 22R (see FIG. 3 ) that can emit near-infrared light and red light.

[0018] The protective film 23 covers the plurality of light-emitting elements 22 and is provided on the surface of the light source substrate 21 facing the sensor substrate 11. The protective film 23 is made of an inorganic film similar to the sealing film 13, or a resin film. The protective film 23 may be a single layer or a laminated film.

[0019] Light emitted from the plurality of light-emitting elements 22 of the light source 20 passes through a detection object such as a finger Fg and enters the plurality of light-detecting elements 12 of the optical sensor 10. This allows the detection device 1 to detect information about a living body inside the finger Fg or the like. The information about the living body includes, for example, the pulse wave, pulse rate, and blood vessel image of the finger or palm. In other words, the detection device 1 may be configured as a vein detection device that detects blood vessel patterns such as veins.

[0020] 3 is a development view showing an example of the sensor substrate and the light source substrate of the detection device according to the first embodiment. Fig. 3 is a development view showing the sensor substrate 11 and the light source substrate 21 developed into a flat plate shape around a virtual central axis along the first side S1. In Fig. 3, the first side S1a, the second side S2a, the third side S3a, and the fourth side S4a of the sensor substrate 11 and the first side S1b, the second side S2b, the third side S3b, and the fourth side S4b of the light source substrate 21 correspond to the first side S1, the second side S2, the third side S3, and the fourth side S4 of the detection device 1 (see Fig. 1), respectively.

[0021] In the following description, the first direction Dx is a direction in a plane parallel to the sensor substrate 11 and the light source substrate 21 when the sensor substrate 11 and the light source substrate 21 are unfolded. The second direction Dy is a direction in a plane parallel to the sensor substrate 11 and the light source 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 a normal direction to the sensor substrate 11 or the light source substrate 21. Furthermore, "planar view" refers to the positional relationship when viewed from a direction perpendicular to the sensor substrate 11 or the light source substrate 21.

[0022] 3 , an adhesive layer 14 is provided in an area along the second side S2a, the third side S3a, and the fourth side S4a of the sensor substrate 11. The adhesive layer 14 is not provided in an area along the first side S1a of the sensor substrate 11. Similarly, an adhesive layer 24 is provided in an area along the second side S2b, the third side S3b, and the fourth side S4b of the light source substrate 21. The adhesive layer 24 is not provided in an area along the first side S1b of the light source substrate 21.

[0023] The adhesive layers 14 and 24 bond together the areas along the second side S2a, the third side S3a, and the fourth side S4a of the sensor substrate 11 and the areas along the second side S2b, the third side S3b, and the fourth side S4b of the light source substrate 21. The area along the first side S1a of the sensor substrate 11 and the area along the first side S1b of the light source substrate 21 are not bonded together, and an opening OP is formed.

[0024] In the optical sensor 10, the multiple photodetection elements 12 are arranged in a matrix on the sensor substrate 11. That is, the multiple photodetection elements 12 are arranged side by side on the sensor substrate 11 in the first direction Dx and the second direction Dy.

[0025] In the light source 20, the plurality of light-emitting elements 22 are arranged in a matrix on the light source substrate 21. That is, the plurality of light-emitting elements 22 are arranged side by side on the light source substrate 21 in the first direction Dx and the second direction Dy. The plurality of light-emitting elements 22 include a plurality of first light-emitting elements 22IR that emit near-infrared light and a plurality of second light-emitting elements 22R that emit red light. The plurality of first light-emitting elements 22IR and the plurality of second light-emitting elements 22R are arranged alternately in the first direction Dx and alternately in the second direction Dy. Note that in FIG. 3, the plurality of first light-emitting elements 22IR and the plurality of second light-emitting elements 22R are shown with different hatching to make the drawing easier to understand.

[0026] The number of the light-emitting elements 22 is greater than the number of the light-detecting elements 12. In other words, the arrangement pitch of the light-emitting elements 22 is smaller than the arrangement pitch of the light-detecting elements 12. For example, in the example shown in Fig. 3, four light-emitting elements 22 (two first light-emitting elements 22IR and two second light-emitting elements 22R) are provided corresponding to one light-detecting element 12.

[0027] This allows the light from the first light-emitting element 22IR and the second light-emitting element 22R to be evenly irradiated onto each of the multiple light-detecting elements 12. In other words, in terms of the arrangement relationship between the multiple light-detecting elements 12 and the multiple light-emitting elements 22, it is possible to prevent the near-infrared light from the first light-emitting element 22IR or the near-infrared light from the second light-emitting element 22R from being unevenly irradiated onto a specific light-detecting element 12.

[0028] The sensor substrate 11 is provided with a third external connection terminal 15, and the light source substrate 21 is provided with a second external connection terminal 25. When the sensor substrate 11 and the light source substrate 21 are arranged opposite each other, the third external connection terminal 15 and the second external connection terminal 25 are arranged overlapping each other and are electrically connected. The plurality of light-emitting elements 22 provided on the light source substrate 21 are electrically connected to an external wiring substrate 30 through the third external connection terminal 15 and the second external connection terminal 25.

[0029] The third external connection terminal 15 and the second external connection terminal 25 shown in Figure 3 are schematically depicted with a simplified configuration, and the connection configuration between the multiple light-emitting elements 22 and the external wiring board 30 will be described later in Figure 4.

[0030] 3 are merely examples and are not intended to be limiting. The photodetector elements 12 are arranged in four rows and four columns, but the arrangement is not limited to this and may be three rows and three columns or less, or five rows and five columns or more. The number of the photodetector elements 12 arranged along the first direction Dx may be different from the number of the photodetector elements 12 arranged along the second direction Dy.

[0031] Fig. 4 is a plan view showing an example of the configuration of the scanning circuit, external connection terminals, and wiring of the detection device according to the first embodiment. Fig. 5 is a block diagram showing an example of the configuration of the control circuit. As shown in Fig. 4, the detection device 1 further includes a sensor scanning circuit 16, a light source scanning circuit 26, a first external connection terminal T1, a third external connection terminal 15, a second external connection terminal 25, wirings L1, L2, L3, L11, L12, L13, L14, and L15, a wiring substrate 30, and a control circuit 50.

[0032] In the optical sensor 10, the first external connection terminal T1 and the third external connection terminal 15 are provided in an area along the second side S2a of the sensor substrate 11. An external wiring substrate 30 is connected to the first external connection terminal T1.

[0033] The sensor scanning circuit 16 includes two sensor scanning circuits 16A and 16B. The sensor scanning circuit 16A is provided in an area along a third side S3a that intersects with the second side S2a of the sensor substrate 11. The sensor scanning circuit 16B is provided in an area along a fourth side S4a that intersects with the second side S2a of the sensor substrate 11. In other words, the sensor scanning circuits 16A and 16B are provided in areas along sides of the sensor substrate 11 that are different from the sides on which the first external connection terminals T1 and the third external connection terminals 15 are provided. In addition, the multiple photodetection elements 12 are arranged between the sensor scanning circuit 16A and the sensor scanning circuit 16B in the second direction Dy.

[0034] A plurality of sensor scanning lines GL are connected to each of the sensor scanning circuits 16A and 16B. The plurality of sensor scanning lines GL extend in the second direction Dy and are connected to a plurality of photodetection elements 12 arranged in the second direction Dy. More specifically, the plurality of sensor scanning lines GL are connected to the gates of the drive transistors Tr (see FIG. 6 ) corresponding to the plurality of photodetection elements 12.

[0035] For example, half of the photodetection elements 12 located on one side in the second direction Dy (the third side S3a side) are connected to the sensor scanning circuit 16A through the sensor scanning lines GL. Also, half of the photodetection elements 12 located on the other side in the second direction Dy (the fourth side S4a side) are connected to the sensor scanning circuit 16B through the sensor scanning lines GL. However, this is not limiting, and the sensor scanning circuits 16A and 16B and the photodetection elements 12 may be connected in any manner.

[0036] The sensor scanning circuit 16A is electrically connected to the wiring board 30 through wiring L1 and the first external connection terminal T1. The sensor scanning circuit 16B is electrically connected to the wiring board 30 through wiring L2 and the first external connection terminal T1. Furthermore, the plurality of photodetection elements 12 provided on the sensor board 11 are electrically connected to the external wiring board 30 through wiring L3 and the first external connection terminal T1.

[0037] In the light source 20 , the second external connection terminal 25 is provided in an area along the second side S2 b of the light source substrate 21 .

[0038] The light source scanning circuit 26 includes two light source scanning circuits 26A and 26B. The light source scanning circuit 26A is provided in an area along a third side S3b that intersects with the second side S2b of the light source substrate 21. The light source scanning circuit 26B is provided in an area along a fourth side S4b that intersects with the second side S2b of the light source substrate 21. In other words, the light source scanning circuits 26A and 26B are provided in areas along a side of the light source substrate 21 that is different from the side on which the second external connection terminals 25 are provided. Furthermore, the multiple light emitting elements 22 are arranged between the light source scanning circuit 26A and the light source scanning circuit 26B in the second direction Dy.

[0039] A plurality of light source scanning lines GUL are connected to each of the light source scanning circuits 26A and 26B. The plurality of light source scanning lines GUL extend in the second direction Dy and are connected to a plurality of light emitting elements 22 arranged in the second direction Dy. Specifically, the plurality of light source scanning lines GUL are connected to gates of light source control transistors TrU (see FIG. 7 ) corresponding to the plurality of light emitting elements 22.

[0040] For example, half of the plurality of light-emitting elements 22 located on one side in the second direction Dy (the side of the third side S3b) are connected to the light source scanning circuit 26A through the plurality of light source scanning lines GUL. Also, half of the plurality of light-detecting elements 12 located on the other side in the second direction Dy (the side of the fourth side S4b) are connected to the light source scanning circuit 26B through the plurality of light source scanning lines GUL. However, this is not limiting, and the light source scanning circuits 26A, 26B and the plurality of light-emitting elements 22 may be connected in any manner.

[0041] The second external connection terminals 25 provided on the light source substrate 21 include second external connection terminals 25a, 25b, 25c, 25d, 25e, and 25f. The third external connection terminals 15 provided on the sensor substrate 11 include third external connection terminals 15a, 15b, 15c, 15d, 15e, and 15f. The third external connection terminals 15a, 15b, 15c, 15d, 15e, and 15f are electrically connected to the second external connection terminals 25a, 25b, 25c, 25d, 25e, and 25f, respectively.

[0042] The light source scanning circuit 26A is electrically connected to the third external connection terminal 15c on the sensor substrate 11 side through the wiring L11 and the second external connection terminal 25c. The light source scanning circuit 26A is electrically connected to the wiring substrate 30 through the third external connection terminal 15c and the first external connection terminal T1.

[0043] The light source scanning circuit 26B is electrically connected to the third external connection terminal 15d on the sensor substrate 11 side through the wiring L14 and the second external connection terminal 25d. The light source scanning circuit 26B is also electrically connected to the wiring substrate 30 through the third external connection terminal 15c and the first external connection terminal T1.

[0044] The plurality of light-emitting elements 22 arranged on the light source substrate 21 are electrically connected to the outside through the second external connection terminal 25. More specifically, among the plurality of light-emitting elements 22, the first light-emitting element 22IR is electrically connected to the third external connection terminal 15a on the sensor substrate 11 side through the wiring L12 and the second external connection terminal 25a. The first light-emitting element 22IR is electrically connected to the wiring substrate 30 through the third external connection terminal 15a and the first external connection terminal T1.

[0045] Of the multiple light-emitting elements 22, the second light-emitting element 22R is electrically connected to the third external connection terminal 15b on the sensor substrate 11 side via the wiring L13 and the second external connection terminal 25b. The second light-emitting element 22R is electrically connected to the wiring substrate 30 via the third external connection terminal 15b and the first external connection terminal T1. The first light-emitting element 22IR and the second light-emitting element 22R are electrically connected to the third external connection terminals 15e and 15f on the sensor substrate 11 side via the wiring L15 and the second external connection terminals 25e and 25f. The first light-emitting element 22IR and the second light-emitting element 22R are supplied with power (drive current) via the wiring L12 and L13. The first light-emitting element 22IR and the second light-emitting element 22R are supplied with a brightness control signal via the wiring L15.

[0046] The control circuit 50 supplies various control signals to the optical sensor 10 through the wiring board 30 and controls the detection of the multiple light detection elements 12 of the optical sensor 10. The control circuit 50 also supplies various control signals to the light source 20 through the wiring board 30 and controls the lighting of the multiple light emitting elements 22 of the light source 20.

[0047] As shown in FIG. 5, the control circuit 50 includes a detection circuit 48, a sensor control circuit 51, a light source control circuit 52, a correction data generation circuit 53, and a memory circuit 54.

[0048] The detection circuit 48 is, for example, an analog front end (AFE) circuit. The detection circuit 48 is electrically connected to the photodetection element 12 of the optical sensor 10, receives a detection signal from the photodetection element 12, and performs predetermined signal processing. Details of the detection circuit 48 will be described later with reference to FIG. 6.

[0049] The sensor control circuit 51 outputs various control signals to the sensor scanning circuit 16 of the optical sensor 10 to control detection by the multiple light detection elements 12. The sensor control circuit 51 also supplies various voltage signals such as a reference potential COM and a sensor power supply signal VDDSNS to the multiple light detection elements 12.

[0050] The light source control circuit 52 outputs various control signals to the light source scanning circuit 26 of the light source 20 to control the lighting of the plurality of light emitting elements 22. The light source control circuit 52 also supplies a drive current to the plurality of light emitting elements 22.

[0051] The correction data generation circuit 53 generates correction data for calibrating the plurality of light detection elements 12. That is, the correction data generation circuit 53 generates correction data so that the plurality of light detection elements 12 will have a constant sensor output when light is irradiated from the plurality of light emitting elements 22 of the light source 20. The generation of correction data will be described later with reference to FIGS.

[0052] The memory circuit 54 stores various information such as the sensor outputs of the multiple light detection elements 12 output from the detection circuit 48 and correction data.

[0053] The control circuit 50 shown in Fig. 5 is merely an example and can be modified as appropriate. For example, the various circuits shown in Fig. 5 may be provided as separate circuits. The control circuit 50 may also include other circuits necessary to realize detection by the optical sensor 10 and lighting of the light source 20.

[0054] Next, an example of the circuit configuration of the optical sensor 10 will be described. Fig. 6 is a circuit diagram showing a plurality of sensor pixels of the optical sensor 10. Note that Fig. 6 also shows the circuit configuration of the detection circuit 48.

[0055] As shown in FIG. 6 , the optical sensor 10 has a plurality of sensor pixels PX arranged in a matrix. Each sensor pixel PX includes a photodetection element 12, a capacitance element Ca, and a drive transistor Tr. The optical sensor 10 has a plurality of sensor scanning lines GL provided on a sensor substrate 11 and a plurality of sensor signal lines SL intersecting the plurality of sensor scanning lines GL. FIG. 6 shows two of the plurality of sensor scanning lines GL, namely, sensor scanning lines GL(m) and GL(m+1), aligned in the second direction Dy. Also shown are two of the plurality of sensor signal lines SL, namely, sensor signal lines SL(n) and SL(n+1), aligned in the first direction Dx. A sensor pixel PX is a region surrounded by the sensor scanning lines GL and the sensor signal lines SL.

[0056] The drive transistor Tr is provided corresponding to the light detection element 12. The drive transistor Tr is configured by a thin film transistor, and in this example, is configured by an n-channel MOS (Metal Oxide Semiconductor) type TFT (Thin Film Transistor).

[0057] Each of the plurality of sensor scanning lines GL is connected to the gates of each of the plurality of drive transistors Tr arranged along the sensor scanning line GL. Each of the plurality of sensor signal lines SL is connected to one of the source and drain of each of the plurality of drive transistors Tr arranged along the sensor signal line SL. The other of the source and drain of each of the plurality of drive transistors Tr is connected to the cathode of the light detection element 12 and the capacitance element Ca.

[0058] A sensor power supply signal VDDSNS is supplied to the anode of the light detection element 12 from the control circuit 50. Furthermore, a reference potential COM, which serves as the initial potential of the sensor signal line SL and the capacitance element Ca, is supplied to the sensor signal line SL and the capacitance element Ca from the control circuit 50 via the reset transistor TrR.

[0059] When light is irradiated onto the sensor pixel PX, a current corresponding to the amount of light flows through the photodetection element 12, causing charge to accumulate in the capacitance element Ca. When the drive transistor Tr is turned on, a current corresponding to the charge accumulated in the capacitance element Ca flows through the sensor signal line SL. The sensor signal line SL is connected to the detection circuit 48 via the connection transistor TrS. This allows the detection device 1 to detect a signal corresponding to the amount of light irradiated onto the photodetection element 12 for each sensor pixel PX.

[0060] During the readout period, the switch SSW of the detection circuit 48 is turned on, and the detection circuit 48 is connected to the sensor signal line SL. The detection signal amplifier circuit 42 of the detection circuit 48 converts the current or charge supplied from the sensor signal line SL into a voltage corresponding to the current or charge. A reference potential (Vref) having a fixed potential is input to the non-inverting input terminal (+) of the detection signal amplifier circuit 42, and the sensor signal line SL is connected to the inverting input terminal (-). In the first embodiment, a signal equal to the reference potential COM is input as the reference potential (Vref). The A / D conversion circuit 43 converts the analog signal output from the detection signal amplifier circuit 42 into a digital signal and outputs it as sensor output data. The detection signal amplifier circuit 42 also has a capacitance element Cb and a reset switch RSW. During the reset period, the reset switch RSW is turned on, and the charge of the capacitance element Cb is reset.

[0061] The driving transistor Tr is not limited to an n-type TFT, but may be a p-type TFT. The pixel circuit of the sensor pixel PX shown in FIG. 3 is merely an example, and the sensor pixel PX may be provided with multiple transistors corresponding to one photodetection element 12.

[0062] Next, an example of the circuit configuration of the light source 20 will be described. Fig. 7 is a circuit diagram showing a drive circuit of the light source. As shown in Fig. 7, the drive circuit of the light source 20 includes a light-emitting element 22, a light-source drive transistor TrD, a light-source control transistor TrU, and a storage capacitor Cc. The light source 20 also has a plurality of light-source scanning lines GUL provided on a light source substrate 21, and a plurality of light-source signal lines SUL that intersect with the plurality of light-source scanning lines GUL.

[0063] The light source drive transistor TrD and the light source control transistor TrU are formed of thin film transistors, and are each configured as an n-type TFT. The light source drive transistor TrD and the light source control transistor TrU are provided for each of the plurality of light emitting elements 22.

[0064] The gate of the light-source driving transistor TrD is connected to the output side of the light-source control transistor TrU. The source of the light-source driving transistor TrD is supplied with anode potentials Vad_IR and Vad_R. The drain of the light-source driving transistor TrD is connected to the anode of the light-emitting element 22. The cathode of the light-emitting element 22 is supplied with cathode potentials Vcd_IR and Vcd_R.

[0065] The gate of the light source control transistor TrU is connected to the light source scanning line GUL. One of the source and drain of the light source control transistor TrU is connected to the light source signal line SUL. The other of the source and drain of the light source control transistor TrU is connected to the gate of the light source drive transistor TrD. In the example shown in FIG. 7 , multiple light-emitting elements 22 arranged in one column are connected to one light source signal line SUL. Furthermore, multiple light-emitting elements 22 in two rows are connected to one light source scanning line GUL. In other words, the first light-emitting element 22IR and the second light-emitting element 22R, which are adjacent to each other across the light source scanning line GUL, are connected to a common light source scanning line GUL.

[0066] When the light source control transistor TrU is turned on (conductive), a predetermined voltage signal (hereinafter referred to as the light source control signal) is supplied from the light source control circuit 52 (see FIG. 5) to the gate of the light source drive transistor TrD. The light source control signal is set according to the light intensity of the light-emitting element 22. That is, the on state (drive current) of the light source drive transistor TrD changes according to the magnitude of the light source control signal supplied to the gate of the light source drive transistor TrD. For example, if the light source control signal corresponds to a voltage signal that maximizes the light intensity of the light-emitting element 22, the source-drain voltage of the light source drive transistor TrD will open to a voltage corresponding to the maximum light intensity. As a result, the light source drive transistor TrD passes a current corresponding to the maximum light intensity and supplies it to the light-emitting element 22. At this time, the anode potential Vad is determined according to the drive current.

[0067] On the other hand, if the light source control signal corresponds to the minimum light intensity of the light emitting element 22 , that is, the signal potential for black, the light source drive transistor TrD is turned off and no current is supplied to the light emitting element 22 .

[0068] In this way, the on state (drive current) of the light source drive transistor TrD changes with a magnitude corresponding to the potential of the light source control signal, and as a result, the current supplied to the light emitting element 22 also corresponds to the on state of the light source drive transistor TrD.

[0069] Furthermore, the storage capacitor Cc is a capacitance formed between the gate and source (input side) of the light-source driving transistor TrD. The drive circuit for the light source 20 shown in FIG. 7 is merely an example and can be modified as appropriate. For example, the transistors shown in FIG. 7 are not limited to p-type TFTs and may be configured with n-type TFTs. For example, while FIG. 7 illustrates a configuration in which the drive circuit for the light source 20 includes two transistors (the light-source driving transistor TrD and the light-source control transistor TrU), this is not limited thereto and the drive circuit may include three or more transistors as necessary. Furthermore, a light-source scanning line GUL may be provided for each of the plurality of light-emitting elements 22 in one row. Furthermore, a light-source scanning line GUL may be provided corresponding to each of the first light-emitting element 22IR and the second light-emitting element 22R.

[0070] Next, a method for detecting a detectable object such as a finger Fg using the detection device 1 will be described. Fig. 8 is a timing chart showing an example of the operation of the detection device according to the first embodiment. In the example shown in Fig. 8, the light source 20 simultaneously turns on or off the first light-emitting element 22IR or the second light-emitting element 22R, and the optical sensor 10 sequentially scans the multiple light-detecting elements 12 in a time-division manner.

[0071] As shown in FIG. 8 , at time t1, the light source scanning circuit 26 supplies a high-level voltage to the light source scanning line GUL of the light source 20 corresponding to the line to be lit, turning on the light source control transistor TrU. In the drive circuit for the light source 20 shown in FIG. 7 , the first light-emitting element 22IR and the second light-emitting element 22R are connected to a common light source scanning line GUL, so that the light source drive transistors TrD of the first light-emitting element 22IR and the second light-emitting element 22R are driven. At time t1, a drive current is supplied to the first light-emitting element 22IR, but not to the second light-emitting element 22R. As a result, at time t1, the first light-emitting element 22IR of the line to be lit is lit, and the second light-emitting element 22R is not lit. At this time, the anode potential Vad is determined according to the drive current.

[0072] When light is irradiated onto the photodetection elements 12 of the optical sensor 10, a current corresponding to the amount of near-infrared light from the first light-emitting element 22IR flows through the photodetection elements 12, causing charge to accumulate in the capacitance element Ca. At time t2, the light source control transistor TrU turns off. At time t3, a predetermined period after time t2, the sensor scanning circuit 16 of the optical sensor 10 sequentially supplies high-level voltages to the sensor scanning lines GL1, GL2, GL3, ..., GL(m). This sequentially turns on the drive transistors Tr of the optical sensor 10 row by row, causing a current to flow through the integration circuit of the detection circuit 48 in accordance with the charge accumulated in the capacitance element Ca. As a result, the detection device 1 calculates the photocurrent for each sensor pixel PX.

[0073] At time t4, the optical sensor 10 finishes scanning the photodetector elements 12 from the first row to the last row, and completes detection for one frame based on the near-infrared light from the first light-emitting element 22IR.

[0074] At time t5, the light source scanning circuit 26 supplies a high-level voltage to the light source scanning line GUL of the light source 20 corresponding to the line to be lit, turning on the light source control transistor TrU. At time t5, no drive current is supplied to the first light-emitting element 22IR, but a drive current is supplied to the second light-emitting element 22R. As a result, at time t5, the first light-emitting element 22IR is turned off, and the second light-emitting element 22R of the line to be lit is turned on. At this time, the anode potential Vad is determined according to the drive current.

[0075] When light is irradiated onto the photodetection elements 12 of the optical sensor 10, a current corresponding to the amount of red light from the second light-emitting element 22R flows through the photodetection elements 12, causing charge to accumulate in the capacitance element Ca. At time t6, the light source control transistor TrU turns off. At time t7, a predetermined period after time t6, the sensor scanning circuit 16 of the optical sensor 10 sequentially supplies high-level voltages to the sensor scanning lines GL1, GL2, GL3, ..., GL(m). This sequentially turns on the drive transistors Tr of the optical sensor 10 row by row, causing a current to flow through the integration circuit of the detection circuit 48 in accordance with the charge accumulated in the capacitance element Ca. As a result, the detection device 1 calculates the photocurrent for each sensor pixel PX.

[0076] At time t8, the optical sensor 10 finishes scanning the photodetector elements 12 from the first row to the last row, and completes detection for one frame based on the red light from the second light-emitting element 22R.

[0077] Fig. 9 is a flowchart showing an example of the operation of the detection device according to the first embodiment. Fig. 10 is a flowchart showing an example of a method for generating sensor correction data. Fig. 11 is an explanatory diagram for explaining step ST11 in Fig. 10. Fig. 12 is an explanatory diagram for explaining a method for generating sensor correction data in Fig. 10. Fig. 13 is an explanatory diagram for explaining an example of a method for detecting a finger region in Fig. 9.

[0078] 9 , the detection device 1 first generates sensor correction data (step ST1). The sensor correction data is generated based on sensor output data acquired from the light detection elements 12 when the light-emitting elements 22 are lit in the absence of a predetermined detection object such as a finger Fg.

[0079] More specifically, in the flow of generating sensor correction data, as shown in FIGS. 10 and 11 , when there is no object to be detected, such as a finger Fg, the light intensity adjustment sheet 32 ​​is inserted between the optical sensor 10 and the light source 20 (step ST11). The light intensity adjustment sheet 32 ​​is a translucent, flat-plate-like member. By passing through the light intensity adjustment sheet 32, light emitted from the light source 20 is attenuated to a light intensity detectable by each light detection element 12 of the optical sensor 10. The light intensity adjustment sheet 32 ​​has a constant thickness, allowing the distance between the light source 20 and the optical sensor 10 to be adjusted to a constant value. Note that the light intensity adjustment sheet 32 ​​may be omitted. In this case, the light source 20 and the optical sensor 10 may be arranged opposite each other so that their entire surfaces are in contact with each other.

[0080] 12, in the flow of generating sensor correction data, the light source 20 turns on the light-emitting element 22 at different light intensities, and the optical sensor 10 acquires sensor output data for each of the different light intensities. In the example shown in FIG. 12, the light source 20 turns on the light-emitting element 22 at 10 different light intensities.

[0081] 10, first, the light source control circuit 52 (see FIG. 5) sets the light intensity of the light emitted from the light source 20 (step ST12). The light source control circuit 52 supplies a light source control signal corresponding to the set light intensity to the light source signal line SUL. As a result, each light emitting element 22 of the light source 20 lights up at the set light intensity (step ST13).

[0082] Light emitted from the light-emitting element 22 passes through the light intensity adjustment sheet 32 ​​and is irradiated onto the light detection element 12 of the optical sensor 10. The light detection element 12 outputs an electrical signal corresponding to the intensity of the irradiated light. The detection circuit 48 performs the predetermined processing described above based on the electrical signal output from the light detection element 12 and outputs sensor output data. As a result, the correction data generation circuit 53 (see FIG. 5) obtains sensor output data corresponding to the set light intensity (step ST14).

[0083] Next, the correction data generating circuit 53 determines whether or not the detection of all preset light intensities has been completed (step ST15).

[0084] If detection of all preset light intensities has not been completed (No in step ST15), the light source control circuit 52 changes the light intensity and executes steps ST12 to ST14.

[0085] When detection of all light intensities has been completed (Yes in step ST15), the correction data generation circuit 53 generates sensor correction data based on the acquired sensor output data So (step ST16).

[0086] 12, in step ST16, the correction data generation circuit 53 generates sensor correction data a1, a2, a3, ..., a10 for each different light intensity based on the difference between the acquired sensor output data So and the sensor reference data REF. The correction data generation circuit 53 also generates sensor correction data a1, a2, a3, ..., a10 for each of the multiple light detection elements 12. The sensor reference data REF is a reference value that indicates the relationship between the light intensity and the sensor output data So, and is stored in advance in the memory circuit 54 (see FIG. 5).

[0087] As described above, the correction data generation circuit 53 generates sensor correction data according to the flows shown in Figures 10 to 12. The sensor correction data is stored in the memory circuit 54 (see Figure 5). The sensor correction data is generated at a predetermined timing, for example, when the detection device 1 is powered on. If the sensor correction data has already been acquired, step ST1 may be omitted.

[0088] 9 , the light source control circuit 52 supplies a control signal to the light source 20 to turn on the plurality of light-emitting elements 22 (step ST2). In step ST2, among the plurality of light-emitting elements 22, the plurality of first light-emitting elements 22IR are simultaneously turned on and the plurality of second light-emitting elements 22R are simultaneously turned off. Alternatively, among the plurality of light-emitting elements 22, the plurality of first light-emitting elements 22IR are simultaneously turned off and the plurality of second light-emitting elements 22R are simultaneously turned on.

[0089] Next, the detection device 1 acquires sensor output data (step ST3). Specifically, the multiple light detection elements 12 of the optical sensor 10 output electrical signals corresponding to the light intensity of light emitted from the multiple light emitting elements 22 and transmitted through the finger Fg. The detection circuit 48 performs the predetermined processing described above based on the electrical signals output from the light detection elements 12 and outputs sensor output data. Also, in step ST3, the sensor control circuit 51 corrects the sensor output data based on the sensor correction data when measuring the finger Fg. The sensor output data acquired in step ST3, or the sensor output data acquired and corrected in step ST3, is stored in the memory circuit 54.

[0090] The sensor control circuit 51 acquires the finger region threshold value TH stored in advance in the memory circuit 54 (step ST4). The finger region threshold value TH is a value obtained by multiplying the sensor output data in an area where a finger Fg is not present by a predetermined coefficient. In the example shown in FIG. 13, the finger region threshold value TH is a value obtained by multiplying the sensor output data in an area where a finger Fg is not present by a coefficient of approximately 0.4. The finger region threshold value TH may be automatically set for each measurement of a finger Fg, or the relationship between the light intensity of the light source 20 and the threshold value TH may be stored in advance in the memory circuit 54.

[0091] 9 and 13, the sensor control circuit 51 detects, as a finger region, a region where the sensor output data output from the plurality of photodetector elements 12 is equal to or less than a predetermined threshold value TH (step ST5). Note that the graph shown in Fig. 13 shows the relationship between the sensor output data and the finger region in the region along the first direction Dx and the second direction Dy. However, the sensor control circuit 51 detects the finger region two-dimensionally based on the sensor output data from the photodetector elements 12 arranged in a matrix.

[0092] The detection device 1 begins measuring the pulse wave in the finger area detected in step ST5 (step ST6). In step ST6, the photodetector elements 12 in the area not overlapping the finger area are driven simultaneously with the photodetector elements 12 in the finger area. However, the sensor control circuit 51 does not use the sensor output data from the photodetector elements 12 in the area not overlapping the finger area to measure the pulse wave, and measures the pulse wave based on the sensor output data from the photodetector elements 12 in the finger area. This allows the detection device 1 to reduce the computational load in measuring the pulse wave. Note that in step ST6, the sensor control circuit 51 may correct the sensor output data based on sensor correction data when measuring the pulse wave.

[0093] The measurement methods shown in FIGS. 9 to 13 are merely examples and may be modified as appropriate.

[0094] 14 is a development view showing an example of the sensor substrate and the light source substrate of the detection device according to the first modification. In the following description, the same components as those described in the above embodiment are denoted by the same reference numerals, and redundant description will be omitted.

[0095] 14 , in the detection device 1A according to the first modification, the plurality of first light-emitting elements 22IR and the plurality of second light-emitting elements 22R of the light source 20A are arranged in a stripe pattern. That is, the plurality of first light-emitting elements 22IR and the plurality of second light-emitting elements 22R are arranged alternately in the second direction Dy. Furthermore, the plurality of first light-emitting elements 22IR and the plurality of second light-emitting elements 22R each extend in the first direction Dx.

[0096] In the first modified example, the arrangement pitch of the first light-emitting elements 22IR and the second light-emitting elements 22R in the second direction Dy is smaller than the arrangement pitch of the light-detecting elements 12 of the optical sensor 10A in the second direction Dy. In other words, the first light-emitting elements 22IR and the second light-emitting elements 22R are arranged so as to overlap one light-detecting element 12.

[0097] In the first embodiment and the first modification, the plurality of first light-emitting elements 22IR and the plurality of second light-emitting elements 22R of the light source 20, 20A are arranged in a matrix or stripe pattern, but this is not limited thereto and other arrangement patterns may be used. Furthermore, the light source 20, 20A is not limited to a configuration that emits two different wavelengths of near-infrared light and red light, but may emit three or more different wavelengths. The light source 20, 20A may have a light-emitting element 22 that emits, for example, green light or blue light.

[0098] Second Embodiment Fig. 15 is a development view showing an example of a sensor substrate and a light source substrate of a detection device according to a second embodiment, and Fig. 16 is a cross-sectional view of the detection device according to the second embodiment.

[0099] 15, in a detection device 1B according to the second embodiment, an optical sensor 10B and a light source 20B share a common substrate 11A. That is, the multiple light detection elements 12 of the optical sensor 10B and the multiple light emitting elements 22 of the light source 20B are formed on the same surface of the substrate 11A.

[0100] The substrate 11A has a sensor region 11Aa, a light source region 11Ab, and a bending region 11Ac. The sensor region 11Aa corresponds to the sensor substrate 11 of the first embodiment and is provided with a plurality of light detection elements 12. The light source region 11Ab corresponds to the light source substrate 21 of the first embodiment and is provided with a plurality of light emitting elements 22. The bending region 11Ac is located between the sensor region 11Aa and the light source region 11Ab. The substrate 11A is formed of a flexible substrate.

[0101] The first side S1a of the sensor region 11Aa and the first side S1b of the light source region 11Ab are provided along the same side of the substrate 11A. The second side S2a of the sensor region 11Aa and the second side S2b of the light source region 11Ab are located on the opposite side of the first sides S1a and S1b and are provided along the same side of the substrate 11A. The third side S3a of the sensor region 11Aa and the third side S3b of the light source region 11Ab are imaginary sides located at the boundary between the sensor region 11Aa and the folding region 11Ac and the boundary between the light source region 11Ab and the folding region 11Ac. The fourth side S4a of the sensor region 11Aa and the fourth side S4b of the light source region 11Ab are located between the first sides S1a and S1b and the second sides S2a and S2b.

[0102] The adhesive layer 14 is provided in the region along the second side S2a, the third side S3a, and the fourth side S4a of the sensor region 11Aa. The adhesive layer 14 is not provided in the region along the first side S1a of the sensor region 11Aa. Similarly, the adhesive layer 24 is provided in the region along the second side S2b, the third side S3b, and the fourth side S4b of the light source region 11Ab. The adhesive layer 24 is not provided in the region along the first side S1b of the light source region 11Ab.

[0103] 16, the substrate 11A is folded at the folding region 11Ac, and the adhesive layer 14 of the sensor region 11Aa and the adhesive layer 24 of the light source region 11Ab are bonded together. That is, in the substrate 11A, the region along the second side S2a, the third side S3a, and the fourth side S4a of the sensor region 11Aa and the region along the second side S2b, the third side S3b, and the fourth side S4b of the light source region 11Ab are bonded together. An opening OP is then formed along the first side S1a of the sensor region 11Aa and the first side S1b of the light source region 11Ab. Furthermore, the plurality of photodetector elements 12 of the sensor region 11Aa and the plurality of light-emitting elements 22 of the light source region 11Ab are arranged to face each other.

[0104] Furthermore, support substrates 17 and 27 are provided in areas of the substrate 11A that overlap with the sensor region 11Aa and the light source region 11Ab, thereby ensuring the strength of the sensor region 11Aa and the light source region 11Ab of the substrate 11A.

[0105] FIG. 17 is a plan view showing an example of the configuration of a scanning circuit, external connection terminals, and wiring of a detection device according to the second embodiment.

[0106] 17, the first external connection terminal T1 is provided only on the optical sensor 10B out of the optical sensor 10B and the light source 20B. The first external connection terminal T1 is provided on the outer edge along the fourth side S4a in the sensor region 11Aa of the substrate 11A. In this embodiment, the third external connection terminal 15 and the second external connection terminal 25 (see FIG. 4) are not provided.

[0107] In the optical sensor 10B, the sensor scanning circuit 16A is provided in an area along the second side S2a that intersects with the fourth side S4a of the sensor area 11Aa. The sensor scanning circuit 16B is provided in an area along the first side S1a that intersects with the fourth side S4a of the sensor area 11Aa. That is, the sensor scanning circuits 16A and 16B are provided in areas along a side of the substrate 11A that is different from the area along the side on which the first external connection terminals T1 are provided. Furthermore, the multiple photodetection elements 12 are arranged between the sensor scanning circuit 16A and the sensor scanning circuit 16B in the second direction Dy.

[0108] The sensor scanning circuit 16A is electrically connected to the first external connection terminal T1 through a wiring L1. The sensor scanning circuit 16B is electrically connected to the first external connection terminal T1 through a wiring L2. The photodetector elements 12 are electrically connected to the first external connection terminal T1 through a wiring L3.

[0109] In the light source 20B, the light source scanning circuit 26A is provided in an area along the second side S2b of the light source region 11Ab. The light source scanning circuit 26B is provided in an area along the first side S1b of the light source region 11Ab. In the second direction Dy, the plurality of light-emitting elements 22 are disposed between the light source scanning circuit 26A and the light source scanning circuit 26B.

[0110] The light source scanning circuit 26A is electrically connected to the first external connection terminal T1 through a wiring L4. The wiring L4 passes between the sensor scanning circuit 16A of the sensor region 11Aa and the second side S2a and is connected to the first external connection terminal T1. The light source scanning circuit 26B is electrically connected to the first external connection terminal T1 through a wiring L5. The wiring L5 passes between the sensor scanning circuit 16B of the sensor region 11Aa and the first side S1a and is connected to the first external connection terminal T1.

[0111] The plurality of light-emitting elements 22 arranged in the light source 20B that is not provided with the first external connection terminal T1 are electrically connected to the first external connection terminal T1 through wirings L6, L7, and L16 provided in the optical sensor 10B and the light source 20B. The wiring L6 passes between the sensor scanning circuit 16A and the plurality of light detection elements 12 in the sensor region 11Aa and is connected to the first external connection terminal T1. The wiring L7 passes between the sensor scanning circuit 16B and the plurality of light detection elements 12 in the sensor region 11Aa and is connected to the first external connection terminal T1. The plurality of wirings L16 are connected to the first external connection terminal T1 through common wiring provided between the sensor scanning circuit 16A and the plurality of light detection elements 12 and between the sensor scanning circuit 16B and the plurality of light detection elements 12.

[0112] In this embodiment, the optical sensor 10B and the light source 20B do not have the third external connection terminal 15 and the second external connection terminal 25, so the process of bonding the sensor region 11Aa and the light source region 11Ab together can be simplified.

[0113] The first external connection terminal T1 is provided in the sensor region 11Aa of the substrate 11A, but is not limited thereto. The first external connection terminal T1 may also be provided in the light source region 11Ab of the substrate 11A. That is, the first external connection terminal T1 may be provided only in the light source 20B out of the optical sensor 10B and the light source 20B. In this case, the multiple light detection elements 12 arranged in the optical sensor 10B that does not have the first external connection terminal T1 are electrically connected to the first external connection terminal T1 through wiring provided in the optical sensor 10B and the light source 20B.

[0114] 18 is a plan view showing an example of the configuration of a scanning circuit, external connection terminals, and wiring of a detection device according to a third embodiment. As shown in FIG. 18, a detection device 1C according to the third embodiment differs from the first and second embodiments in that a light source 20C does not have light source scanning circuits 26A and 26B. In other words, the light source scanning circuits 26A and 26B are not provided in the areas along the third side S3b and the fourth side S4b of the light source substrate 21.

[0115] In the optical sensor 10C, the third external connection terminal 15A is provided in an area along the second side S2a of the sensor substrate 11. The third external connection terminal 15A includes a plurality of third external connection terminals 15Aa, 15Ab, 15Ac, and 15Ad.

[0116] In addition, in the light source 20C, the second external connection terminal 25A is provided in an area along the second side S2b of the light source substrate 21. The second external connection terminal 25A includes a plurality of second external connection terminals 25Aa, 25Ab, 25Ac, and 25Ad. When the sensor substrate 11 and the light source substrate 21 are bonded together facing each other, the plurality of second external connection terminals 25Aa, 25Ab, 25Ac, and 25Ad of the light source 20C are connected to the plurality of third external connection terminals 15Aa, 15Ab, 15Ac, and 15Ad of the optical sensor 10C.

[0117] The plurality of light-emitting elements 22 (first light-emitting element 22IR and second light-emitting element 22R) of light source 20C are electrically connected to second external connection terminals 25Aa, 25Ab, 25Ac, and 25Ad through wiring L8, L9, and L10. The plurality of light-emitting elements 22 are electrically connected to wiring substrate 30 through wiring L8, L9, and L10, third external connection terminal 15A, second external connection terminal 25A, and first external connection terminal T1. As a result, a drive current is supplied to the plurality of light-emitting elements 22 from control circuit 50 (light source control circuit 52).

[0118] 19 is a circuit diagram showing a light source according to the third embodiment. As shown in FIG. 19, the cathode of the first light-emitting element 22IR and the cathode of the second light-emitting element 22R are electrically connected to second external connection terminals 25Aa and 25Ab via wiring L8. The anode of the first light-emitting element 22IR is electrically connected to second external connection terminal 25Ac via wiring L9. The anode of the second light-emitting element 22R is electrically connected to second external connection terminal 25Ad via wiring L10.

[0119] The control circuit 50 (light source control circuit 52) ​​supplies cathode potentials Vcd_IR and Vcd_R to the cathode of the first light-emitting element 22IR and the cathode of the second light-emitting element 22R. The control circuit 50 (light source control circuit 52) ​​also supplies a drive current to the anode of the first light-emitting element 22IR. The control circuit 50 (light source control circuit 52) ​​supplies a drive current to the anode of the second light-emitting element 22R.

[0120] As a result, the first light-emitting element 22IR and the second light-emitting element 22R are lit with light intensities according to the drive current.

[0121] 20 is a timing chart showing an example of operation of the detection device according to the third embodiment. As shown in FIG. 20 , in the example of operation of the detection device 1C according to the third embodiment, the control circuit 50 (light source control circuit 52) ​​supplies drive current to all of the first light-emitting elements 22IR and does not supply drive current to all of the second light-emitting elements 22R at time t1. As a result, during a predetermined period from time t1 to time t2, all of the first light-emitting elements 22IR are simultaneously lit and all of the second light-emitting elements 22R are not lit. In other words, the entire surface of the multiple first light-emitting elements 22IR of the light source 20C is lit simultaneously.

[0122] Furthermore, at time t5, the control circuit 50 (light source control circuit 52) ​​does not supply drive current to any of the first light-emitting elements 22IR, but supplies drive current to all of the second light-emitting elements 22R. As a result, during the period from time t5 to time t6, all of the first light-emitting elements 22IR are turned off, and all of the second light-emitting elements 22R are turned on simultaneously. In other words, the entire surface of the multiple second light-emitting elements 22R of the light source 20C is lit collectively. As a result, the multiple photodetector elements 12 of the optical sensor 10C perform time-division detection of the finger Fg based on near-infrared light and detection of the finger Fg based on red light.

[0123] As described above, the detection device 1C of this embodiment does not have the light source scanning circuits 26A and 26B, and therefore it is possible to reduce the area of ​​the outer edge of the light source substrate 21. Furthermore, since it is not necessary to drive the light source scanning circuits 26A and 26B, it is possible to simplify the configuration of the control circuit 50 (light source control circuit 52).

[0124] 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.

[0125] DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C Detection device 10, 10A, 10B, 10C Optical sensor 11 Sensor substrate 11A Substrate 12 Photodetection element 15, 15a, 15b, 15c, 15d, 15A, 15Aa, 15Ab, 15Ac, 15Ad Third external connection terminal 16, 16A, 16B Sensor scanning circuit 20, 20A, 20B, 20C Light source 21 Light source substrate 22 Light-emitting element 22IR First light-emitting element 22R Second light-emitting element 25, 25a, 25b, 25c, 25d, 25A, 25Aa, 25Ab, 25Ac, 25Ad Second external connection terminal 26, 26A, 26B Light source scanning circuit 30 Wiring substrate 32 Light intensity adjustment sheet 48 Detection circuit OP Opening T1 First external connection terminal

Claims

1. A detection device comprising: a sensor substrate; an optical sensor including a plurality of light detection elements arranged in a plane on the sensor substrate; a light source substrate; and a light source including a plurality of light emitting elements arranged in a plane on the light source substrate and arranged opposite the optical sensor, wherein the sensor substrate and the light source substrate are each flexible substrates, and the sensor substrate and the light source substrate are connected in the shape of a bag having an opening along one side.

2. The detection device according to claim 1, wherein an external connection terminal is provided on only one of the optical sensor and the light source, and the plurality of light detection elements or the plurality of light-emitting elements arranged on the other of the optical sensor and the light source that is not provided with the external connection terminal are electrically connected to the external connection terminal through wiring provided on the optical sensor and the light source.

3. The detection device according to claim 1, comprising a first external connection terminal provided on the sensor substrate and a second external connection terminal provided on the light source substrate, wherein the plurality of light detection elements arranged on the sensor substrate are electrically connected to the outside through the first external connection terminal, and the plurality of light-emitting elements arranged on the light source substrate are electrically connected to the outside through the second external connection terminal.

4. The detection device according to claim 1, wherein the plurality of light detection elements are arranged in a matrix on the sensor substrate, the plurality of light emitting elements are arranged in a matrix on the light source substrate, and the detection device further comprises: a plurality of sensor scanning lines provided on the sensor substrate and a plurality of sensor signal lines intersecting with the plurality of sensor scanning lines; a first external connection terminal provided in an area along one side of the sensor substrate; a sensor scanning circuit provided in an area along an edge intersecting with the one side of the sensor substrate and connected to the plurality of sensor scanning lines; a plurality of light source scanning lines provided on the light source substrate and a plurality of light source signal lines intersecting with the plurality of light source scanning lines; a second external connection terminal provided in an area along the one side of the light source substrate; and a light source scanning circuit provided in an area along the edge intersecting with the one side of the light source substrate and connected to the plurality of light source scanning lines.

5. The detection device according to claim 1, wherein the number of said plurality of light-emitting elements is greater than the number of said plurality of light-detecting elements.

6. The detection device according to claim 1, wherein the plurality of light-emitting elements include a plurality of first light-emitting elements that emit near-infrared light and a plurality of second light-emitting elements that emit red light, and the first light-emitting elements and the second light-emitting elements are arranged alternately.

7. The detection device according to claim 1, further comprising a detection circuit connected to the plurality of photodetector elements, which determines an area where sensor output data output from the plurality of photodetector elements is below a predetermined threshold value as a finger area, and starts measuring a pulse wave in the finger area.

8. The detection device according to claim 1, wherein the plurality of light-emitting elements are lit when a predetermined finger is not present, the detection device has sensor correction data based on sensor output data acquired from the plurality of light-detecting elements, and the detection device corrects the sensor output data based on the sensor correction data when measuring the predetermined finger.

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