Detection device and method for manufacturing light guide part

Abstract

Light is appropriately guided to a light receiving element. A detection device (1) is provided with a plurality of light-receiving elements (PD) that receive light, and a light guide section (102), one surface (102b) of which is provided so as to face the light-receiving elements (PD). The light guide section (102) includes a plurality of light guide paths (110) provided from one surface (102b) of the light guide section (102) to the other surface (102a) of the light guide section (102), and a light absorbing section (112) having a higher light absorption rate than the light guide paths (110). A plurality of light guide paths (110) overlap with one light receiving element (PD) when viewed from a direction in which the light receiving element (PD) overlaps the light guide section (102).

Description

[0001] This invention is based on a divisional application of an invention application with an international application date of March 31, 2020, an international application number of PCT / JP2020 / 014905, a national application number entering the Chinese national phase of 202080033086.1, and an invention name of “Detection device and method for manufacturing a detection device”. Technical Field

[0002] The present invention relates to a detection device and a method for manufacturing a light guide portion. Background Art

[0003] In recent years, optical biometric sensors have been known as biometric sensors for personal authentication and the like (for example, Patent Document 1). An optical biometric sensor has a light receiving element whose output signal changes according to the amount of light received. In the biometric sensor described in Patent Document 1, a plurality of light receiving elements such as light emitting diodes are arranged on a substrate.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: U.S. Patent Application Publication No. 2018 / 0012069 Summary of the invention

[0007] Optical detection devices including biosensors need to guide light to a light receiving element. In optical detection devices, there is room for improvement in order to appropriately guide light to a light receiving element.

[0008] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a detection device and a method for manufacturing the detection device that can appropriately guide light to a light receiving element.

[0009] A detection device according to one aspect of the present invention comprises: a plurality of light receiving elements for receiving light; and an IDE light guiding portion arranged on a surface of one side relative to the light receiving elements, the light guiding portion comprising a plurality of light guiding paths arranged from the surface of the one side to the surface of the other side, and a light absorbing portion having a higher absorption rate of the light than the light guiding path, wherein a plurality of the light guiding paths overlap with respect to one light receiving element when observed from a direction in which the light receiving element and the light guiding portion overlap. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 This is a schematic diagram showing the detection device according to the first embodiment.

[0011] Figure 2 It is a top view of the detection device including the sensor unit.

[0012] Figure 3 It is a block diagram showing a configuration example of a detection device including a sensor unit.

[0013] Figure 4 is a circuit diagram showing a detection device.

[0014] Figure 5 is a circuit diagram showing a local detection area.

[0015] Figure 6 It is a timing waveform diagram showing an operation example of the detection device.

[0016] Figure 7 It is a plan view schematically showing a partial detection area of ​​the detection device according to the first embodiment.

[0017] Figure 8 is along Figure 7 Cross-sectional view along line AA.

[0018] Fig. 9 It is a schematic diagram of the light guide body of the first embodiment.

[0019] Fig.10 It is a schematic diagram of the light guide body of the first embodiment.

[0020] Fig.11A This is a schematic diagram for explaining an example of a method for manufacturing a light guide according to the present embodiment.

[0021] Fig. 11B This is a schematic diagram for explaining another example of the method for manufacturing the light guide according to the present embodiment.

[0022] Fig.12 This is a schematic diagram for explaining an example of the case where light is guided to the light receiving element in the configuration of the first embodiment.

[0023] Fig.13 It is a schematic diagram of a light guide according to a modified example.

[0024] Fig.14 It is a schematic diagram of a light guide according to a modified example.

[0025] Fig.15 It is a schematic diagram of a light guide according to a modified example.

[0026] Fig.16 It is a schematic diagram of a light guide body according to the second embodiment.

[0027] Fig.17 It is a schematic diagram of a light guide body according to the second embodiment.

[0028] Fig.18 It is a schematic diagram of a light guide according to a modified example.

[0029] Fig.19It is a schematic diagram of a light guide according to a modified example.

[0030] Fig. 20 It is a schematic diagram of a light guide according to the third embodiment.

[0031] Fig.21 It is a schematic diagram of a light guide according to a modified example.

[0032] The reference numerals are described as follows:

[0033] 1. Detection device

[0034] 10Sensor unit

[0035] 100 light guide

[0036] 102 Light guide

[0037] 102a, 102b surface

[0038] 104, 106 light-transmitting layer

[0039] 110 light guide path

[0040] 112 light absorption part

[0041] 114 low refractive index part

[0042] PD light receiving element. DETAILED DESCRIPTION

[0043] Hereinafter, various embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the present disclosure is only an example, and appropriate changes that maintain the gist of the invention and are easily conceivable by those skilled in the art are of course included in the scope of the present invention. In addition, in order to make the description clearer, the width, thickness, shape, etc. of each part of the drawings are sometimes schematically indicated compared to the actual form, but this is only an example and does not limit the interpretation of the present invention. In addition, in this specification and the drawings, the same elements as those described in the drawings that have already appeared are marked with the same figure numbers, and the detailed description is sometimes appropriately omitted.

[0044] (First embodiment)

[0045] (Overall structure of the detection device)

[0046] Figure 1 1 is a schematic diagram showing a detection device according to a first embodiment. The detection device 1 according to the first embodiment is a device for detecting information by receiving light L. In this embodiment, the detection device 1 detects biological information of a user. Figure 1 As shown, the detection device 1 includes a light source unit S, a sensor unit 10, a light guide 100, and a cover glass G. The light source unit S, the sensor unit 10, the light guide 100, and the cover glass G are stacked in this order.

[0047] The light source unit S has a light irradiation surface Sa for irradiating light, and irradiates light L0 from the light irradiation surface Sa toward the sensor unit 10. The light source unit S is a backlight. As a light source, the light source unit S may also have, for example, a light emitting diode (LED) that emits light of a predetermined color. In addition, the light source unit S may also be a so-called side-lit backlight having a light guide plate provided at a position corresponding to the sensor unit 10, and a plurality of light sources arranged at one end or both ends of the light guide plate. In addition, the light source unit S may also be a so-called directly below-type backlight having a light source (for example, LED) provided directly below the sensor unit 10. In addition, the light source unit S is not limited to a backlight, and may be provided on the side or above the sensor unit 10, or may irradiate light L0 from the side or above the user's finger Fg. That is, the light source unit S may also be provided on the side of the detected object (finger Fg) compared to the light guide 100. In addition, when natural light is used as the light L, the light source unit S may not be provided.

[0048] The sensor unit 10 is disposed opposite to the light irradiation surface Sa of the light source unit S. The light L0 irradiated from the light source unit S is transmitted through the sensor unit 10, the light guide 100, and the cover glass G. The sensor unit 10 is, for example, a light reflection type biological information sensor, and detects the light L as the reflected light of the light L0, thereby being able to detect the surface unevenness (for example, fingerprint) of the user's finger Fg or palm. In addition, the sensor unit 10 can detect a blood vessel pattern or other biological information by detecting the light L reflected inside the finger Fg or palm. In addition, the wavelength of the light L from the light source unit S can also be made different depending on the detection object. For example, in the case of fingerprint detection, the light L0 of visible light can be irradiated from the light source unit S, and in the case of blood vessel pattern detection, the light L0 of near-infrared light can be irradiated from the light source unit S. Visible light is light in the wavelength domain of the visible light region, and near-infrared light is light in the wavelength domain of the near-infrared region, for example, a wavelength domain of 700 nm or more and 950 nm or less.

[0049] The light guide 100 is provided on the detection object (finger Fg) side of the sensor unit 10 and faces the sensor unit 10. The light guide 100 is an optical element that guides the light L to the sensor unit 10. The configuration of the light guide 100 will be described later.

[0050] The cover glass G is a member for protecting the sensor unit 10 and the light source unit S, and covers the light guide 100, the sensor unit 10, and the light source unit S. The cover glass G is, for example, a glass substrate. In addition, the cover glass G is not limited to a glass substrate, and may also be a resin substrate, etc. In addition, the cover glass G may not be provided.

[0051] The detection device 1 may also be provided with a display panel instead of the light source unit S. The display panel may be, for example, an organic EL display panel (OLED: Organic Light Emitting Diode) or an inorganic EL display (μ-LED, Mini-LED). Alternatively, the display panel may be a liquid crystal display panel (LCD: Liquid Crystal Display) using a liquid crystal element as a display element, or an electrophoretic display panel (EPD: Electrophoretic Display) using an electrophoretic element as a display element. In this case, the display light irradiated from the display panel is also transmitted from the sensor unit 10, and the user's biological information can be detected based on the light L reflected by the finger Fg.

[0052] (Sensor part)

[0053] Next, the sensor unit 10 will be described. Figure 2 It is a top view of the detection device including the sensor unit. Figure 3 1 is a block diagram showing an example of the configuration of a detection device including a sensor unit. Figure 2 As shown, the detection device 1 includes an insulating substrate 21 , a sensor unit 10 , a gate line driving circuit 15 , a signal line selecting circuit 16 , an analog front end circuit (hereinafter referred to as AFE (Analog Front End)) 48 , a control circuit 20 , and a power supply circuit 203 .

[0054] like Figure 2 As shown, the insulating substrate 21 is electrically connected to the control substrate 201 via the flexible printed substrate 71. The flexible printed substrate 71 is provided with an AFE 48. The control substrate 201 is provided with a control circuit 202 and a power supply circuit 203. The control circuit 202 is, for example, an FPGA (Field Programmable Gate Array). The control circuit 202 supplies control signals to the sensor unit 10, the gate line driving circuit 15, and the signal line selection circuit 16 to control the detection operation of the sensor unit 10. The power supply circuit 203 transmits the power supply signal SVS (refer to Figure 5 ) and the like are supplied to the sensor unit 10 and the gate line driving circuit 15.

[0055] like Figure 2 As shown in FIG. 1 , the insulating substrate 21 has a detection area AA and a peripheral area GA. The detection area AA is a region corresponding to the plurality of light receiving elements PD (see FIG. 1 ) included in the sensor unit 10. Figure 5 The peripheral area GA is an area outside the detection area AA and is an area that does not overlap with the light receiving element PD. The gate line driving circuit 15 and the signal line selecting circuit 16 are provided in the peripheral area GA.

[0056] like Figure 3 As shown, the detection device 1 further includes a detection control unit 11 and a detection unit 40. A part or all of the functions of the detection control unit 11 are included in the control circuit 202. In addition, a part or all of the functions of the detection unit 40 other than the AFE 48 are included in the control circuit 202.

[0057] The sensor unit 10 is a light sensor having a light receiving element PD as a photoelectric conversion element. The light receiving element PD is a photoelectric conversion element, more specifically, a light emitting diode, and outputs an electrical signal corresponding to the received light as a detection signal Vdet to the signal line selection circuit 16. In addition, the sensor unit 10 performs detection according to the gate drive signal VGCL supplied from the gate line drive circuit 15.

[0058] The detection control unit 11 is a circuit that supplies control signals to the gate line driving circuit 15, the signal line selection circuit 16, and the detection unit 40 to control these operations. The detection control unit 11 supplies various control signals such as a start signal STV, a clock signal CK, and a reset signal RST1 to the gate line driving circuit 15. In addition, the detection control unit 11 supplies various control signals such as a selection signal SEL to the signal line selection circuit 16.

[0059] The gate line driving circuit 15 drives a plurality of gate lines GCL based on various control signals (see Figure 4 The gate line driving circuit 15 selects a plurality of gate lines GCL sequentially or simultaneously and supplies a gate driving signal VGCL to the selected gate lines GCL. Thus, the gate line driving circuit 15 selects a plurality of light receiving elements PD connected to the gate lines GCL.

[0060] The signal line selection circuit 16 selects a plurality of signal lines SGL in sequence or simultaneously (see Figure 4 The signal line selection circuit 16 connects the selected signal line SGL and the AFE 48 based on the selection signal SEL supplied from the detection control unit 11. Thus, the signal line selection circuit 16 outputs the detection signal Vdet of the light receiving element PD to the detection unit 40.

[0061] The detection unit 40 includes an AFE 48, a signal processing unit 44, a coordinate extraction unit 45, a storage unit 46, and a detection timing control unit 47. The detection timing control unit 47 controls the AFE 48, the signal processing unit 44, and the coordinate extraction unit 45 to operate synchronously based on a control signal supplied from the detection control unit 11.

[0062] The AFE 48 is a signal processing circuit having at least the functions of the detection signal amplifier 42 and the A / D converter 43. The detection signal amplifier 42 amplifies the detection signal Vdet. The A / D converter 43 converts the analog signal output from the detection signal amplifier 42 into a digital signal.

[0063] The signal processing unit 44 is a logic circuit that detects a predetermined physical quantity input to the sensor unit 10 based on the output signal of the AFE 48. The signal processing unit 44 can detect biological information based on the signal from the AFE 48 when a finger contacts or approaches the detection surface.

[0064] The storage unit 46 temporarily stores the signal calculated by the signal processing unit 44. The storage unit 46 may be, for example, a RAM (Random Access Memory), a register circuit, or the like.

[0065] The coordinate extraction unit 45 is a logic circuit that obtains the detection coordinates of the concave and convex surface of the finger, etc. when the signal processing unit 44 detects the contact or approach of the finger. The coordinate extraction unit 45 combines the detection signals Vdet output from each light receiving element PD of the sensor unit 10 to generate two-dimensional information representing the shape of the concave and convex surface of the finger, etc. In addition, the coordinate extraction unit 45 may output the detection signal Vdet as the sensor output Vo without calculating the detection coordinates.

[0066] Next, a circuit configuration example and an operation example of the detection device 1 will be described. Figure 4 is a circuit diagram showing a detection device. Figure 5 is a circuit diagram showing a local detection area. Figure 6 It is a timing waveform diagram showing an operation example of the detection device.

[0067] like Figure 4 As shown in FIG. 1 , the sensor unit 10 has a plurality of local detection areas PAA arranged in a matrix. Figure 5 As shown, the local detection area PAA includes a light receiving element PD, a capacitor element Ca, and a first switch element Tr. The first switch element Tr is provided corresponding to the light receiving element PD. The first switch element Tr is composed of a thin film transistor, and in this example, is composed of an n-channel MOS (Metal Oxide Semiconductor) type TFT (Thin Film Transistor). The gate of the first switch element Tr is connected to the gate line GCL. The source of the first switch element Tr is connected to the signal line SGL. The drain of the first switch element Tr is connected to the anode of the light receiving element PD and the capacitor element Ca.

[0068] A power supply signal SVS is supplied to the cathode of the light receiving element PD from the power supply circuit 203. In addition, a reference signal VR1 serving as an initial potential of the capacitive element Ca is supplied to the capacitive element Ca from the power supply circuit 203.

[0069] When light is irradiated to the local detection area PAA, a current corresponding to the amount of light flows to the light receiving element PD, thereby accumulating charge in the capacitor element Ca. When the first switch element Tr is turned on, a current flows to the signal line SGL corresponding to the charge accumulated in the capacitor element Ca. The signal line SGL is connected to the AFE 48 via the signal line selection circuit 16. Thus, the detection device 1 can detect a signal corresponding to the amount of light irradiated to the light receiving element PD for each local detection area PAA.

[0070] like Figure 4 As shown, the gate line GCL extends in the first direction Dx and is connected to a plurality of local detection areas PAA arranged in the first direction Dx. In addition, a plurality of gate lines GCL1, GCL2, ..., GCL8 are arranged in the second direction Dy and are respectively connected to the gate line driving circuit 15. In addition, in the following description, when it is not necessary to distinguish between a plurality of gate lines GCL1, GCL2, ..., GCL8, they are only represented as gate lines GCL. The number of gate lines GCL is 8, but this is just an example, and the gate lines GCL can be more than 8, for example, 256 gate lines are arranged.

[0071] In addition, the first direction Dx is a direction in a plane parallel to the insulating substrate 21, for example, a direction parallel to the gate line GCL. In addition, the second direction Dy is a direction in a plane parallel to the insulating substrate 21, and is a direction orthogonal to the first direction Dx. In addition, the second direction Dy may not be orthogonal to the first direction Dx but may cross it. In addition, the direction orthogonal to the first direction Dx and the second direction Dy is set as the third direction Dz. The third direction Dz is a direction orthogonal to the plane parallel to the insulating substrate 21.

[0072] The signal line SGL extends in the second direction Dy and is connected to a plurality of local detection areas PAA arranged in the second direction Dy. In addition, a plurality of signal lines SGL1, SGL2, ..., SGL12 are arranged in the first direction Dx and are connected to the signal line selection circuit 16 and the reset circuit 17, respectively. The number of signal lines SGL is 12, but this is only an example, and the number of signal lines SGL may be more than 12, for example, 252. In addition, Figure 4 In the embodiment, the sensor unit 10 is provided between the signal line selection circuit 16 and the reset circuit 17. However, the present invention is not limited thereto, and the signal line selection circuit 16 and the reset circuit 17 may be connected to the ends of the signal line SGL in the same direction.

[0073] The gate line driving circuit 15 receives various control signals such as a start signal STV, a clock signal CK, and a reset signal RST via a level converter 151. The gate line driving circuit 15 includes a plurality of second switching elements TrG (see Figure 8 ), and a shift register (not shown). The gate line driving circuit 15 selects a plurality of gate lines GCL1, GCL2, ..., GCL8 in sequence in time division according to the operation of the shift register and the second switching element TrG. The gate line driving circuit 15 supplies a gate driving signal VGCL to a plurality of first switching elements Tr via the selected gate lines GCL. Thus, a plurality of local detection areas PAA arranged in the first direction Dx are selected as detection objects.

[0074] The signal line selection circuit 16 has a plurality of selection signal lines Lsel, a plurality of output signal lines Lout, and a third switch element TrS. The plurality of third switch elements TrS are respectively provided corresponding to the plurality of signal lines SGL. The six signal lines SGL1, SGL2, ..., SGL6 are connected to a common output signal line Lout1. The six signal lines SGL7, SGL8, ..., SGL12 are connected to a common output signal line Lout2. The output signal lines Lout1 and Lout2 are respectively connected to the AFE 48.

[0075] Here, the signal lines SGL1, SGL2, ..., SGL6 are set as the first signal line block, and the signal lines SGL7, SGL8, ..., SGL12 are set as the second signal line block. A plurality of selection signal lines Lsel are respectively connected to the gates of the third switch elements TrS contained in one signal line block. In addition, one selection signal line Lsel is connected to the gates of the third switch elements TrS of a plurality of signal line blocks. Specifically, the selection signal lines Lsel1, Lsel2, ..., Lsel6 are connected to the third switch elements TrS corresponding to the signal lines SGL1, SGL2, ..., SGL6. In addition, the selection signal line Lsel1 connects the third switch element TrS corresponding to the signal line SGL1 and the third switch element TrS corresponding to the signal line SGL7. The selection signal line Lsel2 connects the third switch element TrS corresponding to the signal line SGL2 and the third switch element TrS corresponding to the signal line SGL8.

[0076] Control circuit 202 (see Figure 2) supplies the selection signal SEL to the selection signal line Lsel in sequence via the level converter 161. Thus, the signal line selection circuit 16 sequentially selects the signal lines SGL in a time-division manner in one signal line block through the operation of the third switch element TrS. In addition, the signal line selection circuit 16 selects the signal lines SGL one by one in a plurality of signal line blocks at the same time. According to this configuration, the detection device 1 can reduce the number of ICs (Integrated Circuits) including the AFE 48, or the number of IC terminals.

[0077] like Figure 4 As shown, the reset circuit 17 has a reference signal line Lvr, a reset signal line Lrst, and a fourth switch element TrR. The fourth switch element TrR is provided corresponding to the plurality of signal lines SGL. The reference signal line Lvr is connected to one of the source or drain of the plurality of fourth switch elements TrR. The reset signal line Lrst is connected to the gate of the plurality of fourth switch elements TrR.

[0078] The control circuit 202 supplies the reset signal RST2 to the reset signal line Lrst via the level converter 171. As a result, the plurality of fourth switch elements TrR are turned on, and the plurality of signal lines SGL are electrically connected to the reference signal line Lvr. The power supply circuit 203 supplies the reference signal VR1 to the reference signal line Lvr. As a result, the reference signal VR1 is supplied to the capacitive elements Ca included in the plurality of local detection areas PAA.

[0079] like Figure 6 As shown, the detection device 1 has a reset period Prst, an exposure period Pex, and a reading period Pdet. The power supply circuit 203 supplies the power supply signal SVS to the cathode of the light receiving element PD through the reset period Prst, the exposure period Pex, and the reading period Pdet. In addition, before the reset period Prst starts, the control circuit 202 supplies the reference signal VR1 of the high level voltage signal and the reset signal RST2 to the reset circuit 17. The control circuit 202 supplies the start signal STV to the gate line drive circuit 15 to start the reset period Prst.

[0080] During the reset period Prst, the shift register included in the gate line driving circuit 15 sequentially selects the gate line GCL based on the start signal STV, the clock signal CK, and the reset signal RST1. The gate line driving circuit 15 sequentially supplies the gate driving signal VGCL to the gate line GCL. The gate driving signal VGCL has a pulse waveform having a high level voltage VGH and a low level voltage VGL. Figure 6 In the embodiment, 256 gate lines GCL are provided, and gate driving signals VGCL1, ..., VGCL256 are sequentially supplied to the gate lines GCL.

[0081] Thus, in the reset period Prst, the capacitive elements Ca of all the partial detection areas PAA are electrically connected to the signal line SGL in sequence and supplied with the reference signal VR1 , thereby resetting the capacitance of the capacitive element Ca.

[0082] After the gate drive signal VGCL256 is supplied to the gate line GCL, the exposure period Pex begins. In addition, the actual start timing and end timing of the exposure periods Pex1, ..., Pex256 in the local detection area PAA corresponding to each gate line GCL are different. The exposure periods Pex1, ..., Pex256 start at the timing when the gate drive signal VGCL changes from the high level voltage VGH to the low level voltage VGL in the reset period Prst, respectively. In addition, the exposure periods Pex1, ..., Pex256 end at the timing when the gate drive signal VGCL changes from the low level voltage VGL to the high level voltage VGH in the reading period Pdet, respectively. The exposure time of the exposure periods Pex1, ..., Pex256 is equal in length.

[0083] In the exposure period Pex, a current flows in each local detection area PAA in accordance with the light irradiated to the light receiving element PD, and as a result, electric charge is accumulated in each capacitive element Ca.

[0084] At a timing before the start of the reading period Pdet, the control circuit 202 sets the reset signal RST2 to a low level voltage. As a result, the operation of the reset circuit 17 stops. In the reading period Pdet, similarly to the reset period Prst, the gate line drive circuit 15 sequentially supplies the gate drive signals VGCL1, ..., VGCL256 to the gate lines GCL.

[0085] For example, during the period when the gate drive signal VGCL1 is a high-level voltage VGH, the control circuit 202 sequentially supplies the selection signals SEL1, ..., SEL6 to the signal line selection circuit 16. Thus, the signal line SGL of the local detection area PAA selected by the gate drive signal VGCL1 is connected to the AFE48 sequentially or simultaneously. As a result, the detection signal Vdet is supplied to the AFE48. Similarly, for each period in which each gate drive signal VGCL becomes a high-level voltage VGH, the signal line selection circuit 16 sequentially selects the signal line SGL. Thus, during the reading period Pdet, the detection device 1 outputs the detection signal Vdet of all local detection areas PAA to the AFE48.

[0086] The detection device 1 may repeatedly execute the reset period Prst, the exposure period Pex, and the reading period Pdet to perform fingerprint detection. Alternatively, the detection device 1 may start the detection operation at the timing when it detects that a finger or the like has contacted or approached the detection surface.

[0087] Next, the detailed configuration of the detection device 1 will be described. Figure 7 It is a plan view schematically showing a partial detection area of ​​the detection device according to the first embodiment. Figure 8 It is along Figure 7 The AA line cross-sectional view. Figure 8 In order to show the relationship between the layer structure of the detection area AA and the layer structure of the surrounding area GA, a cross section along the AA line and a cross section of a portion including the second switching element TrG of the surrounding area GA are schematically shown in succession. Figure 8 , a cross section of a portion including the terminal portion 72 of the peripheral area GA is schematically shown continuously.

[0088] In the description of the detection device 1, in the direction perpendicular to the surface of the insulating substrate 21 (third direction Dz), the direction from the insulating substrate 21 toward the light receiving element PD is referred to as the "upper side". The direction from the light receiving element PD toward the insulating substrate 21 is referred to as the "lower side". In addition, "viewed from above" means the situation of observing from the direction perpendicular to the surface of the insulating substrate 21.

[0089] like Figure 7 As shown in FIG. 1 , the local detection area PAA is an area surrounded by the gate line GCL and the signal line SGL. In the present embodiment, the gate line GCL includes a first gate line GCLA and a second gate line GCLB. The first gate line GCLA and the second gate line GCLB are overlapped. The first gate line GCLA and the second gate line GCLB are connected to each other via an insulating layer (the third inorganic insulating layer 22c and the fourth inorganic insulating layer 22d (see FIG. 1 ). Figure 8 )) are provided in different layers. The first gate line GCLA and the second gate line GCLB are electrically connected at any point and are supplied with a gate drive signal VGCL having the same potential. At least one of the first gate line GCLA and the second gate line GCLB is connected to the gate line drive circuit 15. In addition, Figure 7 In the embodiment, the first gate line GCLA and the second gate line GCLB have different widths, but may also have the same width.

[0090] The light receiving element PD is provided in a region surrounded by the gate line GCL and the signal line SGL. The light receiving element PD includes a third semiconductor 31, an upper electrode 34, and a lower electrode 35. The light receiving element PD is, for example, a PIN (Positive Intrinsic Negative Diode) type light emitting diode or a light emitting diode composed of an organic semiconductor.

[0091] Specifically, if Figure 8As shown, the light receiving element PD is stacked with a lower electrode 35, a third semiconductor 31, and an upper electrode 34 in the order of a lower electrode 35, a third semiconductor 31, and an upper electrode 34 on the first organic insulating layer 23a of the back plate 2. The back plate 2 is a driving circuit substrate for driving the sensor for each specified detection area. The back plate 2 has an insulating substrate 21, a first switching element Tr provided on the insulating substrate 21, a second switching element TrG, and various wirings.

[0092] The third semiconductor 31 is amorphous silicon (a-Si). The third semiconductor 31 includes an i-type semiconductor 32a, a p-type semiconductor 32b, and an n-type semiconductor 32c. The i-type semiconductor 32a, the p-type semiconductor 32b, and the n-type semiconductor 32c are a specific example of a photoelectric conversion element. Figure 8 In the direction perpendicular to the surface of the insulating substrate 21, an n-type semiconductor 32c, an i-type semiconductor 32a, and a p-type semiconductor 32b are stacked in the order of an n-type semiconductor 32c, an i-type semiconductor 32a, and a p-type semiconductor 32b. However, the opposite structure may be used, that is, a p-type semiconductor 32b, an i-type semiconductor 32a, and an n-type semiconductor 32c may be stacked in the order of a p-type semiconductor 32b, an i-type semiconductor 32a, and an n-type semiconductor 32c. In addition, the third semiconductor 31 may be a photoelectric conversion element composed of an organic semiconductor. In this case, the semiconductor 32a is a bulk heterojunction of a p-type semiconductor and an n-type semiconductor, and the semiconductor 32b and the semiconductor 32c are respectively composed of a charge transport layer or a charge blocking layer for electrons and holes.

[0093] The lower electrode 35 is the anode of the light receiving element PD and is an electrode for reading the detection signal Vdet. The lower electrode 35 uses a metal material such as molybdenum (Mo) or aluminum (Al). Alternatively, the lower electrode 35 may be a laminated film in which a plurality of these metal materials are laminated. The lower electrode 35 may be a light-transmitting conductive material such as ITO (Indium Tin Oxide).

[0094] The n-type semiconductor 32c is formed by doping impurities into a-Si to form an n+ region. The p-type semiconductor 32b is formed by doping impurities into a-Si to form a p+ region. The i-type semiconductor 32a is, for example, an undoped intrinsic semiconductor and has lower conductivity than the n-type semiconductor 32c and the p-type semiconductor 32b.

[0095] The upper electrode 34 is a cathode of the light receiving element PD and is an electrode for supplying a power supply signal SVS to the photoelectric conversion layer. The upper electrode 34 is a light-transmitting conductive layer such as ITO, and a plurality of upper electrodes are provided for each light receiving element PD.

[0096] like Figure 8As shown in the figure, a sixth inorganic insulating layer 22f and a seventh inorganic insulating layer 22g are provided on the first organic insulating layer 23a. The sixth inorganic insulating layer 22f covers the peripheral portion of the upper electrode 34, and is provided with an opening at a position overlapping with the upper electrode 34. The connection wiring 36 is connected to the upper electrode 34 at a portion of the upper electrode 34 where the sixth inorganic insulating layer 22f is not provided. The seventh inorganic insulating layer 22g covers the upper electrode 34 and the connection wiring 36, and is provided on the sixth inorganic insulating layer 22f. The second organic insulating layer 23b as a planarization layer is provided on the seventh inorganic insulating layer 22g. In addition, in the case of an organic semiconductor light-emitting diode, there is a case where an eighth inorganic insulating layer 22h is further provided thereon.

[0097] like Figure 7 As shown, the upper electrode 34 is connected to the power signal line Lvs via the connecting wiring 36. The power signal line Lvs is a wiring for supplying the power signal SVS to the light receiving element PD. In the present embodiment, the power signal line Lvs overlaps with the signal line SGL and extends in the second direction Dy. A plurality of local detection areas PAA arranged in the second direction Dy are connected to a common power signal line Lvs. According to this configuration, the opening of the local detection area PAA can be enlarged. The lower electrode 35, the third semiconductor 31 and the upper electrode 34 are quadrilateral in a plan view. However, it is not limited thereto, and the shapes of the lower electrode 35, the third semiconductor 31 and the upper electrode 34 can be appropriately changed.

[0098] like Figure 7 As shown in FIG. 1 , the first switching element Tr is provided near the intersection of the gate line GCL and the signal line SGL. The first switching element Tr includes a first semiconductor 61 , a source electrode 62 , a drain electrode 63 , a first gate electrode 64A, and a second gate electrode 64B.

[0099] The first semiconductor 61 is an oxide semiconductor. More preferably, the first semiconductor 61 is a transparent amorphous oxide semiconductor (TAOS) among oxide semiconductors. By using an oxide semiconductor for the first switching element Tr, the leakage current of the first switching element Tr can be suppressed. Figure 6 In the reading period Pdet shown, the leakage current from the non-selected local detection area PAA can be reduced. Therefore, the detection device 1 can improve the S / N ratio.

[0100] The first semiconductor 61 is arranged along the first direction Dx, and intersects with the first gate electrode 64A and the second gate electrode 64B when viewed from above. The first gate electrode 64A and the second gate electrode 64B are arranged to branch from the first gate line GCLA and the second gate line GCLB, respectively. In other words, the portions of the first gate line GCLA and the second gate line GCLB that overlap with the first semiconductor 61 function as the first gate electrode 64A and the second gate electrode 64B. The first gate electrode 64A and the second gate electrode 64B use aluminum (Al), copper (Cu), silver (Ag), molybdenum (Mo) or alloys thereof. In addition, a channel region is formed in the portion of the first semiconductor 61 that overlaps with the first gate electrode 64A and the second gate electrode 64B.

[0101] One end of the first semiconductor 61 is connected to the source electrode 62 via the contact hole H1. The other end of the first semiconductor 61 is connected to the drain electrode 63 via the contact hole H2. The portion of the signal line SGL that overlaps with the first semiconductor 61 serves as the source electrode 62. In addition, the portion of the third conductive layer 67 that overlaps with the first semiconductor 61 functions as the drain electrode 63. The third conductive layer 67 is connected to the lower electrode 35 via the contact hole H3. According to this configuration, the first switching element Tr can switch the connection and disconnection between the light receiving element PD and the signal line SGL.

[0102] Next, the layer structure of the first switching element Tr will be described. Figure 8 As shown, the first switch element Tr is provided on an insulating substrate 21. The insulating substrate 21 is, for example, a glass substrate. Alternatively, the insulating substrate 21 may be a resin substrate or a resin film made of a resin such as polyimide. The first switch element Tr including an oxide semiconductor of the detection device 1 is formed on the insulating substrate 21. Therefore, the detection device 1 can easily increase the area of ​​the detection area AA compared to the case where a semiconductor substrate such as a silicon substrate is used.

[0103] The second gate electrode 64B is provided on the insulating substrate 21 via the first inorganic insulating layer 22a and the second inorganic insulating layer 22b. The inorganic insulating layers such as the first inorganic insulating layer 22a and the second inorganic insulating layer 22b use silicon oxide film (SiO), silicon nitride film (SiN) or silicon oxynitride film (SiON). In addition, each inorganic insulating layer is not limited to a single layer, and may be a laminated film.

[0104] The third inorganic insulating layer 22c covers the second gate electrode 64B and is provided on the second inorganic insulating layer 22b. The first semiconductor 61, the first conductive layer 65, and the second conductive layer 66 are provided on the third inorganic insulating layer 22c. The first conductive layer 65 is provided to cover the end portion of the first semiconductor 61 connected to the source electrode 62. The second conductive layer 66 is provided to cover the end portion of the first semiconductor 61 connected to the drain electrode 63.

[0105] The fourth inorganic insulating layer 22d covers the first semiconductor 61, the first conductive layer 65, and the second conductive layer 66 and is provided on the third inorganic insulating layer 22c. The first gate electrode 64A is provided on the fourth inorganic insulating layer 22d. The first semiconductor 61 is provided between the first gate electrode 64A and the second gate electrode 64B in a direction perpendicular to the insulating substrate 21. That is, the first switching element Tr is a so-called double gate structure. However, the first switching element Tr may be a top gate structure in which the first gate electrode 64A is provided and the second gate electrode 64B is not provided, or may be a bottom gate structure in which the first gate electrode 64A is not provided and only the second gate electrode 64B is provided.

[0106] The fifth inorganic insulating layer 22e covers the first gate electrode 64A and is provided on the fourth inorganic insulating layer 22d. The source electrode 62 (signal line SGL) and the drain electrode 63 (third conductive layer 67) are provided on the fifth inorganic insulating layer 22e. In the present embodiment, the drain electrode 63 is the third conductive layer 67 provided on the first semiconductor 61 via the fourth inorganic insulating layer 22d and the fifth inorganic insulating layer 22e. The fourth inorganic insulating layer 22d and the fifth inorganic insulating layer 22e are provided with a contact hole H1 and a contact hole H2. The first conductive layer 65 is exposed at the bottom of the contact hole H1. The source electrode 62 is electrically connected to the first semiconductor 6 via the contact hole H1 and the first conductive layer 65. Similarly, the second conductive layer 66 is exposed at the bottom of the contact hole H2. The drain electrode 63 is electrically connected to the first semiconductor 61 via the contact hole H2 and the second conductive layer 66.

[0107] The first conductive layer 65 is provided between the source electrode 62 and the first semiconductor 61, at least in a portion overlapping with the bottom of the contact hole H1, and is in contact with the first semiconductor 61. The second conductive layer 66 is provided between the drain electrode 63 and the first semiconductor 61, at least in a portion overlapping with the bottom of the contact hole H2, and is in contact with the first semiconductor 61. Since the first conductive layer 65 and the second conductive layer 66 are provided, the detection device 1 can remove the first semiconductor 61 by an etching solution when the contact holes H1 and H2 are formed by etching. That is, the detection device 1 can form the first switching element Tr of the detection area AA and the second switching element TrG of the peripheral area GA by the same process, and thus the manufacturing cost can be suppressed.

[0108] Metal materials such as aluminum (Al), copper (Cu), silver (Ag), molybdenum (Mo), or alloys thereof are used for the first conductive layer 65, the second conductive layer 66, and the third conductive layer 67. The first conductive layer 65 and the second conductive layer 66 may be made of any conductive material as long as the progress of etching is suppressed when the contact holes H1 and H2 are formed.

[0109] The third conductive layer 67 is provided in a region overlapping with the light receiving element PD in a plan view. The third conductive layer 67 is also provided on the upper side of the first semiconductor 61, the first gate electrode 64A, and the second gate electrode 64B. That is, the third conductive layer 67 is provided between the first gate electrode 64A and the lower electrode 35 in a direction perpendicular to the insulating substrate 21. Thus, the third conductive layer 67 has a function as a protective layer for protecting the first switching element Tr.

[0110] The second conductive layer 66 extends opposite to the third conductive layer 67 in a region not overlapping with the first semiconductor 61. In addition, a fourth conductive layer 68 is provided on the fourth inorganic insulating layer 22d in a region not overlapping with the first semiconductor 61. The fourth conductive layer 68 is provided between the second conductive layer 66 and the third conductive layer 67. Thus, a capacitor is formed between the second conductive layer 66 and the fourth conductive layer 68, and a capacitor is formed between the third conductive layer 67 and the fourth conductive layer 68. The capacitor formed by the second conductive layer 66, the third conductive layer 67, and the fourth conductive layer 68 is Figure 5 The capacitance of the capacitive element Ca is shown.

[0111] The first organic insulating layer 23a is provided on the fifth inorganic insulating layer 22e so as to cover the source electrode 62 (signal line SGL) and the drain electrode 63 (third conductive layer 67). The first organic insulating layer 23a is a flattening layer that flattens the concavities and convexities formed by the first switching element Tr or various conductive layers. The light receiving element PD is provided on the first organic insulating layer 23a. The lower electrode 35 is electrically connected to the third conductive layer 67 via the contact hole H3 provided in the first organic insulating layer 23a. That is, the third conductive layer 67 is electrically connected to the lower electrode 35 as the anode of the light receiving element PD, and is provided between the light receiving element PD and the first gate electrode 64A of the first switching element Tr.

[0112] The second switching element TrG of the gate line driving circuit 15 is provided in the peripheral area GA. The second switching element TrG and the first switching element Tr are provided on the same insulating substrate 21. The second switching element TrG includes a second semiconductor 81, a source electrode 82, a drain electrode 83, and a gate electrode 84.

[0113] The second semiconductor 81 is polycrystalline silicon. More preferably, the second semiconductor 81 is low temperature polycrystalline silicon (hereinafter referred to as LTPS (Low Temperature Polycrystalline Silicone)). The second switching element TrG using LTPS can be manufactured at a process temperature below 600°C. Therefore, circuits such as the gate line driving circuit 15 or the signal line selection circuit 16 can be formed on the same substrate as the first switching element Tr. Polycrystalline silicon has higher carrier mobility than a-Si. Therefore, the detection device 1 can miniaturize the gate line driving circuit 15 by using polycrystalline silicon for the second switching element TrG. As a result, the detection device 1 can reduce the area of ​​the peripheral area GA. In addition, the second switching element TrG using polycrystalline silicon has higher reliability than a-Si.

[0114] The second semiconductor 81 is provided on the first inorganic insulating layer 22a. That is, the first semiconductor 61 of the first switching element Tr is provided at a position farther from the insulating substrate 21 than the second semiconductor 81 of the second switching element TrG in a direction perpendicular to the insulating substrate 21. Thus, the second semiconductor 81 composed of polycrystalline silicon and the first semiconductor 61 composed of an oxide semiconductor can be formed on the same insulating substrate 21.

[0115] The gate electrode 84 is provided on the upper side of the second semiconductor 81 via the second inorganic insulating layer 22b. The gate electrode 84 is provided in the same layer as the second gate electrode 64B. The second switching element TrG has a so-called top gate structure. However, the second switching element TrG may have a double gate structure or a bottom gate structure.

[0116] The source electrode 82 and the drain electrode 83 are provided on the fifth inorganic insulating layer 22e. The source electrode 82 and the drain electrode 83 are provided on the same layer as the source electrode 62 and the drain electrode 63 of the first switching element Tr. The contact holes H4 and H5 are provided from the second inorganic insulating layer 22b to the fifth inorganic insulating layer 22e. The source electrode 82 is electrically connected to the second semiconductor 81 via the contact hole H4. The drain electrode 83 is electrically connected to the second semiconductor 81 via the contact hole H5.

[0117] The contact holes H4 and H5 are formed in four layers of inorganic insulating layers (the second inorganic insulating layer 22b to the fifth inorganic insulating layer 22e), and the contact holes H1 and H2 are formed in two layers of inorganic insulating layers (the fourth inorganic insulating layer 22d and the fifth inorganic insulating layer 22e). That is, the length of the contact holes H4 and H5 in the direction perpendicular to the insulating substrate 21 is longer than that of the contact holes H1 and H2. In this case, the first conductive layer 65 and the second conductive layer 66 are also provided in the first switching element Tr, so that the detection device 1 can form the contact holes H1 and H2 and the contact holes H4 and H5 by the same process.

[0118] also, Figure 4 The third switch element TrS of the signal line selection circuit 16 shown can also be configured in the same manner as the second switch element TrG. That is, the semiconductor of the third switch element TrS is polysilicon, preferably LTPS. In this case, the detection device 1 can suppress the circuit scale of the signal line selection circuit 16. However, the semiconductor of the third switch element TrS can also be an oxide semiconductor including TAOS. Similarly, Figure 4 The fourth switch element TrR of the reset circuit 17 shown can also be configured in the same manner as the second switch element TrG. That is, the semiconductor of the fourth switch element TrR is polysilicon, more preferably LTPS. In this case, the detection device 1 can suppress the circuit scale of the reset circuit 17. However, the present invention is not limited thereto, and the semiconductor of the fourth switch element TrR can also be an oxide semiconductor including TAOS.

[0119] The terminal portion 72 is provided at a position different from the region in the peripheral region GA where the gate line driving circuit 15 is provided. The terminal portion 72 includes a first terminal conductive layer 73, a second terminal conductive layer 74, a third terminal conductive layer 75, and a fourth terminal conductive layer 76. The first terminal conductive layer 73 is provided on the second inorganic insulating layer 22b in the same layer as the second gate electrode 64B. The contact hole H6 is provided to connect the third inorganic insulating layer 22c, the fourth inorganic insulating layer 22d, the fifth inorganic insulating layer 22e, and the first organic insulating layer 23.

[0120] The second terminal conductive layer 74, the third terminal conductive layer 75, and the fourth terminal conductive layer 76 are stacked in this order in the contact hole H6 and are electrically connected to the first terminal conductive layer 73. The second terminal conductive layer 74 can be formed using the same material and the same process as the third conductive layer 67. In addition, the third terminal conductive layer 75 can be formed using the same material and the same process as the lower electrode 35. The fourth terminal conductive layer 76 can be formed using the same material and the same process as the connection wiring 36 and the power signal line Lvs (see Figure 7 ) are made of the same materials and formed by the same process.

[0121] In addition, Figure 8 1 shows a terminal portion 72, and a plurality of terminal portions 72 are arranged at intervals. The plurality of terminal portions 72 are connected to a flexible printed substrate 71 ( Figure 1 Reference) Electrical connection.

[0122] The sensor unit 10 has the above-described structure, and therefore can appropriately detect the biological information of the user. However, the sensor unit 10 is not limited to the structure described above as long as it can detect the biological information of the user by receiving the light L using the light receiving element PD. In addition, the sensor unit 10 can detect information other than biological information by receiving the light L using the light receiving element PD.

[0123] (Light guide)

[0124] Next, the light guide 100 is described. The light guide 100 is a member that guides the light L to the light receiving element PD. In the present embodiment, the light guide 100 is made of an organic material, more specifically, a polymer material, and is elastically deformable. However, the light guide 100 may be made of any material described below, and is not limited to an organic material.

[0125] Fig. 9 as well as Fig.10 It is a schematic diagram of the light guide body of the first embodiment. Fig. 9 is a cross-sectional view of the light guide 100, Fig.10 1 is a diagram showing the light guide 100 when viewed from the third direction Dz. Fig. 9 As shown, the light guide 100 is provided on the sensor unit 10 in the third direction Dz. That is, the third direction Dz can be said to be a direction in which the light guide 100 (light guide unit 102) and the sensor unit 10 (light receiving element PD) overlap. The light guide 100 includes a light guide unit 102, and light-transmitting layers 104 and 106. The light guide 100 is a plate-shaped laminated body in which the light-transmitting layer 106, the light guide unit 102, and the light-transmitting layer 104 are laminated in the order of the light-transmitting layer 106, the light guide unit 102, and the light-transmitting layer 104 in the third direction Dz. In the third direction Dz, the light-transmitting layer 106 is provided on the sensor unit 10 side, that is, on the light receiving element PD side, and the light-transmitting layer 104 is provided on the side of the detected object (finger Fg, etc.).

[0126] The light-transmitting layer 106 is a sheet-shaped member. The upper surface 106a of the light-transmitting layer 106 is in contact with the light-guiding portion 102, and the surface 106b on the opposite side (lower side) of the surface 106a is in contact with the sensor portion 10 (in the Figure 8In the example of the second organic insulating layer 23b or the eighth inorganic insulating layer 22h). The light-transmitting layers 104 and 106 are composed of a component that transmits light L. The light-transmitting layers 104 and 106 are, for example, PET (Polyethylene Terephthalate), PC (Polycarbonate), PEN (Polyethylene Naphthalate), polyimide, or transparent polyimide, alicyclic epoxy resin, fluoropolyester, PPS (Polyphenylene sulfide), but the material is not limited to this as long as it is a component that transmits light L. In addition, the light-transmitting layers 104 and 106 preferably have a transmittance of light L equal to that of the light guide path 110 of the light guide portion 102 described later. The refractive index of the light L of the light-transmitting layers 104 and 106 is preferably greater than the refractive index of the light L of the light guide path 110 of the light guide portion 102, for example, preferably not less than 1.4 and not more than 1.8. In addition, the light-transmitting layer 104 and the light-transmitting layer 106 may have different transmittances or refractive indices.

[0127] In addition, the light-transmitting layers 104 and 106 are not essential components and may not be included in the light guide 100. For example, the light guide 100 may not include the light-transmitting layer 104 and the light-transmitting layer 106, or may include at least one of the light-transmitting layers 104 and 106.

[0128] The light guide 102 is a sheet-like member. The upper surface 102a of the light guide 102 is in contact with the light-transmitting layer 104b, and the surface 102b on the opposite side (lower side) of the surface 102a is in contact with the surface 106a of the light-transmitting layer 106. That is, the surface 102b of the light guide 102 is opposite to the sensor unit 10 (light-receiving element PD) via the light-transmitting layer 106. The light guide 102 includes a light guide path 110 and a light absorbing unit 112.

[0129] The light guide path 110 is a path that can transmit light L. In the present embodiment, the light guide path 110 is a solid member that can transmit light L. The transmittance of light in the light guide path 110 is higher than the transmittance of light L in the light absorption portion 112 described later. The transmittance of light in the light guide path 110 is preferably not less than 50% and not more than 100%. The transmittance of light L here refers to the ratio of the intensity of the emitted light L to the intensity of the incident light L. In addition, the refractive index of light in the light guide path 110 is preferably not less than 1.40 and not more than 1.70. The light guide path 110 is an organic material, more specifically a polymer material, such as a silicone resin, an acrylic resin, an epoxy resin, etc. Further, the light guide path 110 is preferably a photopolymer that is cured by receiving irradiation with light, such as a silicone photopolymer, an acrylic photopolymer, an epoxy photopolymer, etc. In addition, the light guide path 110 may also be a path containing a material having a higher refractive index of light L than the organic material such as silicone-based photopolymers, acrylic-based photopolymers, epoxy-based photopolymers, etc. As the material with a high refractive index, for example, there are transition metal alkoxides such as titanium oxide or zirconium oxide. However, the light guide path 110 is not limited to the material composition described above as long as it is a path that can transmit light L. For example, the light guide path 110 is not solid, but may be a space containing a gas such as air. In this case, the light guide path 110 can also be said to be an opening of the light guide portion 102, and the refractive index of light L becomes 1.

[0130] like Fig.10 As shown in FIG. 1 , a plurality of light guide paths 110 are provided in a matrix in the first direction Dx and the second direction Dy. Fig.10 In the example of , the light guide paths 110 are arranged in a square lattice in the light guide portion 102 when viewed from the third direction Dz, but the arrangement method is not limited thereto and is arbitrary, for example, they may be arranged in a hexagonal lattice. The spacing of the light guide paths 110, that is, the distance between the centers of adjacent light guide paths 110, is preferably equal for all light guide paths 110, but is not limited thereto and may be different for each light guide path 110.

[0131] In addition, if Fig. 9 As shown, the light guide path 110 is provided from the surface 102a to the surface 102b of the light guide portion 102. That is, it can be said that the upper surface 110a of the light guide path 110 constitutes the surface 102a of the light guide portion 102, and the surface 110b on the opposite side (lower side) of the surface 110a constitutes the surface 102b of the light guide portion 102. In addition, the central axis Ax of the light guide path 110 is substantially along the third direction Dz, and is substantially orthogonal to the first direction Dx and the second direction Dy.

[0132] In the present embodiment, the light guide path 110 is cylindrical, and the diameter D1 is fixed in the third direction Dz. In addition, in the present embodiment, the diameter D1 of all the light guide paths 110 is equal. However, the light guide path 110 may not be cylindrical, for example, it may be a polygonal prism such as a quadrangular prism. In addition, the length in the third direction Dz from the surface 110a to the surface 110b of the light guide path 110 is set to length D2. The length D2 can also be referred to as the length of the light guide portion 102 in the third direction Dz. The length D2 is preferably not less than 10 μm and not more than 300 μm. By setting the length D2 within this numerical range, the light guide 100 can be flexibly elastically deformed, so that it can be applied to detection devices 1 of various shapes.

[0133] In addition, the ratio of the length D2 to the diameter D1 is set as the aspect ratio of the light guide path 110. The aspect ratio of the light guide path 110 is preferably greater than 2, more preferably greater than 5, and further preferably greater than 10. By setting such an aspect ratio, the viewing angle when acquiring an image of the object to be detected (finger Fg, etc.) can be reduced, and the blur when photographing the object to be detected separated by a distance can be reduced. In addition, the aspect ratio of the light guide path 110 is preferably, for example, less than 20. By setting the aspect ratio to less than 20, it is possible to appropriately manufacture.

[0134] In addition, if Fig.10 As shown, when viewed from the third direction Dz, the light guide path 110 is arranged to overlap with the light receiving element PD. More specifically, when viewed from the third direction Dz, a plurality of light guide paths 110 overlap with respect to one light receiving element PD. Further, a plurality of light guide paths 110 overlap with respect to each light receiving element PD. That is, when viewed from the third direction Dz, a plurality of light guide paths 110 are arranged in an area where one light receiving element PD is formed. Fig.10 In the example, nine light guide paths 110 overlap one light receiving element PD, but the number of light guide paths 110 overlapping one light receiving element PD is not limited to nine, and any number of light guide paths 110 may be used as long as it is a plurality. In addition, light guide paths 110 may exist between adjacent light receiving elements PD, or a portion of light guide paths 110 may be located between adjacent light receiving elements PD.

[0135] The light absorbing portion 112 is provided in a manner surrounding the light guide path 110. In the present embodiment, the light absorbing portion 112 is provided in the entire region of the portion of the light guide portion 102 where the light guide path 110 is not provided. Therefore, the light guide path 110 of the present embodiment can be said to be formed in the portion surrounded by the light absorbing portion 112 in the light guide portion 102. The light absorbing portion 112 is provided from the surface 102a of the light guide portion 102 to the surface 102b. That is, it can be said that the surface 112a on the upper side of the light absorbing portion 112 constitutes the surface 102a of the light guide portion 102, and the surface 112b on the opposite side (lower side) to the surface 112a constitutes the surface 102b of the light guide portion 102.

[0136] The light absorbing part 112 is composed of a component that absorbs light L, and the absorption rate of light L is higher than that of the light guiding path 110. The absorption rate of light L of the light absorbing part 112 is preferably 70% to 100%, and more preferably 100%. The absorption rate of light L here refers to the ratio of the difference between the intensity of incident light L and the intensity of emitted light L relative to the intensity of incident light L. The light absorbing part 112 is an organic material, more specifically a polymer material, such as acrylic resin, epoxy resin, polyimide resin or siloxane polymer resin. The light absorbing part 112 is also preferably a polymer that is cured by irradiation with light or heat treatment, for example, an acrylic photopolymer with a small curing shrinkage rate. Moreover, the light absorbing part 112 may also include carbon black or titanium black such as titanium oxide or titanium oxynitride, metal oxides such as iron oxide, and dyes or organic pigments that absorb light L in addition to these organic materials.

[0137] The light guide 100 has the above-described configuration. Next, an example of a method for manufacturing the light guide 100 will be described. Fig.11A Schematic diagram for explaining an example of a method for manufacturing a light guide according to the present embodiment. Fig.11A As shown, initially, as shown in step S10 (first coating step), a light-transmitting layer 106 is formed on a substrate SUB, and a first organic material M1 is coated on the light-transmitting layer 106. The substrate SUB is a substrate used for forming the light guide 100, such as a glass substrate. The first organic material M1 is, for example, formed on the entire area of ​​the surface 106a of the light-transmitting layer 106. The first organic material M1 is a component of an uncured light guide path 110. The first organic material M1 is, for example, an organic material having fluidity including one or more photopolymerizable monomer components. In addition, the first organic material M1 may be an organic material having fluidity including one or more photopolymerizable monomer components and a plurality of components of oligomers that are difficult to photopolymerize. In addition, the first organic material M1 may include both an organic material having fluidity including one or more photopolymerizable monomer components and an organic material having fluidity including one or more photopolymerizable monomer components and a plurality of components of oligomers that are difficult to photopolymerize.

[0138] Next, as shown in step S12 (light guide path forming step), the first organic material M1 provided on the light-transmitting layer 106 is irradiated with patterned light U. Fig.11A In the example, a light source unit 300 and a pattern forming unit 302 are used to irradiate patterned light U. The light source unit 300 is a light source that generates the light U. The pattern forming unit 302 is a component provided with a plurality of transmission units 302A. The transmission units 302A are configured to transmit the light U. The transmission units 302A have an inner diameter corresponding to the diameter D1 of the light guide path 110 (for example, an inner diameter equal to the diameter D1). In addition, the transmission units 302A are arranged in a manner corresponding to the pitch of the light guide path 110 (for example, at the same pitch as the pitch of the light guide path 110). The transmission units 302A may be a component that transmits the light U, or may be an opening. In addition, the light U is light that can cure the first organic material M1, for example, ultraviolet light.

[0139] In step S12, the pattern forming section 302 is arranged between the light source section 300 and the first organic material M1, and the light U is irradiated from the light source section 300 toward the upper surface of the first organic material M1. The light L from the light source section 300 is irradiated, for example, onto the entire area of ​​the pattern forming section 302. The light U irradiated onto the pattern forming section 302 passes through the transmission section 302A of the pattern forming section 302 and irradiates onto the upper surface of the first organic material M1. Therefore, only the portion of the first organic material M1 corresponding to the pattern of the transmission section 302A is irradiated with the light U. The portion of the first organic material M1 irradiated with the light U is cured and becomes the light guide path 110. Moreover, the portion not irradiated with the light U is not cured and remains as the first organic material M1. That is, in step S12, a plurality of light guide paths 110 standing upright along the third direction Dz are formed in the first organic material M1 that is not photopolymerized and not cured.

[0140] In step S12 , the pattern forming section 302 is used to irradiate the first organic material M1 with the patterned light U, but the present invention is not limited to using the pattern forming section 302 . Fig. 11B is a schematic diagram illustrating another example of a method for manufacturing a light guide according to the present embodiment. Fig. 11B As shown, the light source unit 300 includes a plurality of light sources 301 arranged in a pattern without providing a pattern forming unit, and light U (collimated light) having a straight-forward property may be directly irradiated from each light source 301. By irradiating such collimated light, when a cylindrical microphase separation pattern is formed in the first organic material M1 by the self-organization function of the material, a plurality of light guide paths 110 standing upright along the third direction Dz are formed in the first organic material M1 that is not photopolymerized and not cured.

[0141] Next, as shown in step S14 (removal step), the first organic material M1 that is not photopolymerized and not cured is removed from the substrate SUB. For example, the first organic material M1 is removed by immersing it in a dissolving liquid. As a result, only the plurality of light guide paths 110 remain on the light-transmitting layer 106.

[0142] Next, as shown in step S16 (second coating step), the second organic material M2 is coated on the light-transmitting layer 106. The second organic material M2 is coated on the area of ​​the light-transmitting layer 106 where the light-guiding path 110 is not provided (the area where the first organic material M1 is removed). That is, the second organic material M2 is coated around each light-guiding path 110. The second organic material M2 is an uncured light-absorbing portion 112 and has fluidity. In addition, in step S16, it is preferred that the surface 110a on the upper side of the light-guiding path 110 is not covered by the second organic material M2. However, even if the surface 110a is covered by the second organic material M2, the surface 110a can be exposed by removing the upper surface of the light-absorbing portion 112 formed by the second organic material M2 by subsequent machining or etching.

[0143] Next, as shown in step S18 (light absorbing portion forming step), the second organic material M2 provided on the light-transmitting layer 106 is irradiated with light U1 from the light source unit 310. The second organic material M2 is cured by the irradiation of the light U1 to form the light absorbing portion 112. Thus, the light-guiding portion 102 is formed on the light-transmitting layer 106. In addition, the light U1 can be ultraviolet light or the like, similarly to the light U. In addition, the second organic material M2 can also be cured by heat to form the light absorbing portion 112. In this case, in step S18, the second organic material M2 is heated to be cured instead of being irradiated with the light U1. Alternatively, curing can be performed by using both light and heat. In this case, the shape is maintained by irradiation with the light U1, and curing is performed by subsequent heat.

[0144] Next, as shown in step S20, a light-transmitting layer 104 is formed on the light-guiding portion 102. Thus, the light-guiding body 100 is formed on the substrate SUB. Alternatively, the light-transmitting layer 104 may be cured after being applied, or a solid light-transmitting layer 104 may be attached to the light-guiding portion 102.

[0145] Next, as shown in step S22, the light guide 100 is removed from the substrate SUB and is provided on the sensor unit 10. In addition, the detection device 1 is manufactured through a process of also installing other components of the detection device 1. In addition, in the case of removing the light guide 100 from the substrate SUB, the light guide 100 can also be peeled off from the substrate SUB using a laser lift-off method. In this case, a laser is irradiated from the surface opposite to the surface of the light guide 100 on which the substrate SUB is provided. The laser is transmitted through the substrate SUB and irradiated to the surface (surface 106b) of the light guide 100 that is in contact with the substrate SUB. The surface of the light guide 100 that is in contact with the substrate SUB is peeled off from the substrate SUB using the laser.

[0146] Next, a case where the light L is guided to the light receiving element PD will be described. Fig.12 This is a schematic diagram for explaining an example of the case where light is directed to the photosensitive element in the configuration of the first embodiment. Here, in a detection device that receives light L and detects information, it is necessary to properly direct the light L to the photosensitive element PD. For example, if the intensity of the light L directed to the photosensitive element PD is very small or light from a part other than the part to be detected is directed to the photosensitive element PD, there is a concern that the information cannot be properly detected. In addition, when light L from a wide range is directed to the photosensitive element PD, the intensity of the light L received by each photosensitive element PD will be close to equal, resulting in a phenomenon such as blurred images. In contrast, if Fig.12 As shown in FIG. 1 , the detection device 1 of this embodiment includes a light guide unit 102 for guiding light to the light receiving element PD. The light guide unit 102 overlaps a plurality of light guide paths 110 with respect to one light receiving element PD. Fig.12 As shown, the light L passing through the plurality of light guide paths 110 can be guided to the light receiving element PD. Therefore, according to the detection device 1, it is possible to suppress, for example, a situation where the intensity of the light L guided to the light receiving element PD decreases. In addition, the light guide path 110 can be used to limit the range of the incident angle of the light L that can be incident on the light receiving element PD through the light guide path 110, that is, the incident range angle θ. That is, the light La whose angle formed by the central axis Ax of the light guide path 110 and the direction of travel of the light is within the range of the incident range angle θ passes through the light guide path 110 and reaches the light receiving element PD. On the other hand, the light Lb whose angle formed by the central axis Ax of the light guide path 110 and the direction of travel of the light is outside the range of the incident range angle θ is irradiated to the inner peripheral surface of the light absorbing portion 112 in the light guide path 110 and is absorbed, and does not reach the light receiving element PD. Therefore, according to the detection device 1, it is possible to suppress the light L from a wide range from reaching the light receiving element PD, thereby deepening the depth of the depth of field. In addition, even if light Lc from outside the area to be detected (for example, light from the area to be detected by an adjacent light receiving element PD) approaches the light receiving element PD, it can be blocked by the light absorbing portion 112, thereby preventing light Lc from outside the range to be detected from reaching the light receiving element PD.

[0147] As described above, the detection device 1 of the first embodiment has a plurality of light receiving elements PD that receive light L, and a light guide portion 102 whose surface 102b is arranged opposite to the light receiving element PD. The light guide portion 102 includes a plurality of light guide paths 110 and a light absorbing portion 112. The light guide path 110 is arranged from the surface 102a of the light guide portion 102 to the surface 102b. The light absorbing portion 112 has a higher absorption rate of light L than the light guide path 110. Moreover, when the detection device 1 is observed from the direction (the third direction Dz) in which the light receiving element PD and the light guide portion 102 overlap, a plurality of light guide paths 110 overlap with respect to one light receiving element PD. The detection device 1 of this embodiment overlaps a plurality of light guide paths 110 with respect to one light receiving element PD, thereby being able to guide the light L passing through the plurality of light guide paths 110 to the light receiving element PD, thereby suppressing a decrease in the intensity of the light L guided to the light receiving element PD. Furthermore, the detection device 1 can suppress light L from a wide range or light L from outside the range to be detected from reaching the light receiving element PD by including the light absorbing portion 112. Thus, the detection device 1 of this embodiment can appropriately guide the light L to the light receiving element PD.

[0148] The light guide path 110 is formed of a solid member having a higher transmittance of light L than the light absorbing portion 112. By forming the light guide path 110 of a solid member having a high transmittance of light L, the light L can be appropriately guided to the light receiving element PD.

[0149] In addition, the light guide unit 102 is preferably made of an organic material. By forming the light guide unit 102 with an organic material, the light guide unit 102 can be elastically deformed flexibly, and can be applied to detection devices 1 of various shapes.

[0150] In addition, the manufacturing method of the detection device 1 of the present embodiment includes a first coating step, a light guide path forming step, a removal step, a second coating step, and a light absorbing portion forming step. In the first coating step, the first organic material M1 is coated on the substrate SUB. In the light guide path forming step, the area of ​​the light guide path 110 formed by the first organic material M1 coated on the substrate SUB is irradiated with light U, so that the first organic material M1 in the area irradiated with light U is cured, and the cured first organic material M1 is set as the light guide path 110. In the removal step, the uncured first organic material M1 is removed from the substrate SUB. In the second coating step, the area on the substrate SUB where the light guide path 110 is not formed is coated with the second organic material M2. In the light absorbing portion forming step, the second organic material M2 on the substrate SUB is irradiated with light U1 so that the second organic material M2 is cured, thereby forming a light absorbing portion 112. According to the manufacturing method of this embodiment, the detection device 1 that appropriately guides the light L to the light receiving element PD can be appropriately manufactured.

[0151] (Variation Example)

[0152] Next, a modification of the first embodiment will be described. In the first embodiment, all the light guide paths 110 have the same diameter, but as shown in the following modification, the diameters may be different for different light guide paths. Fig.13 Schematic diagram of a light guide of a modified example. Fig.13 As shown, the inner diameters of the light guide paths 110A1 and 110A2 of the light guide portion 102A of the light guide body 100A of the modified example are different. The light guide paths 110A1 and 110A2 overlap with the same light receiving element PD. The diameter D1A2 of the light guide path 110A2 is larger than the diameter D1A1 of the light guide path 110A1. Therefore, the aspect ratios of the light guide paths 110A1 and 110A2 are different, and the aspect ratio of the light guide path 110A2 (the ratio of the length D2 to the diameter D1A2) is smaller than the aspect ratio of the light guide path 110A1 (the ratio of the length D2 to the diameter D1A1). For example, the aspect ratio of the light guide path 110A2 is greater than 2, and the aspect ratio of the light guide path 110A1 is preferably greater than 10. By making the aspect ratio different in this way, the range of the incident angle of the light L that can enter the light receiving element PD through the light guide path 110A1, that is, the incident range angle θA1, can be set to be smaller than the range of the incident angle of the light L that can enter the light receiving element PD through the light guide path 110A2, that is, the incident range angle θA2. As a result, the depth of field in the light guide path 110A1 can be deepened.

[0153] As described above, in the light guide path 110A, the aspect ratios of the plurality of light guide paths overlapping with one light receiving element PD are different from each other. By making the aspect ratios different in this way, different types of biological information can be appropriately detected. For example, by irradiating visible light as light L0 and guiding the visible light L as the reflected light to the light receiving element PD, biological information can be detected as a fingerprint. In addition, for example, by irradiating near-infrared light as light L0 and guiding the near-infrared light L as the reflected light to the light receiving element PD, a blood vessel pattern can be detected as biological information. In this case, by allowing the visible light L to pass through the light guide path 110A1 and reach the light receiving element PD, a fingerprint can be detected with high precision. In addition, by allowing the near-infrared light L to pass through the light guide path 110A2 and reach the light receiving element PD, a blood vessel pattern can be detected with high precision. For example, by providing a filter that transmits visible light and absorbs near-infrared light in the light guide path 110A1, and providing a filter that transmits near-infrared light and absorbs visible light in the light guide path 110A2, the respective light guide paths can be appropriately distinguished for use, but such filters are not necessarily required. Fig.13In the figure, the light guide path 110A1 and the light guide path 110A2 are illustrated as having different diameters and aspect ratios. However, three or more light guide paths may have different diameters and aspect ratios.

[0154] In the first embodiment, the diameter D1 of the light guide path 110 is constant at each position in the third direction Dz, but the diameter D1 of the light guide path 110 may be different at each position in the third direction Dz. Fig.14 as well as Fig.15 Schematic diagram of a light guide of a modified example. Fig.14 As shown in FIG. 1 , in the light guide portion 102B of the light guide 100B of the modified example, the diameter of the light guide path 110B is different at each position in the third direction Dz. In other words, the light guide path 110B has a positive cone shape in which the diameter decreases as it approaches the surface 110b (surface 102b) toward the surface 110a (102a). That is, the diameter D1B1 of the light guide path 110B on the surface 110a side is smaller than the diameter D1B2 of the light guide path 110B on the surface 110b side.

[0155] As the diameter of the light guide path 110B decreases as it approaches the surface 102a, the range of the incident angle of the light L that can be incident on the light receiving element PD through the light guide path 110B, that is, the incident range angle θB can be reduced compared to, for example, a case where the diameter is fixed. That is, by setting the light guide 110B to a positive cone shape while achieving the same aspect ratio as when the diameter D1 of the light guide path 110 is fixed, the thickness of the light guide portion 102B can be effectively reduced. Therefore, it is possible to suppress the light L from a wide range from reaching the light receiving element PD, deepen the depth of field, and appropriately guide the light L to the light receiving element PD.

[0156] In addition, if Fig.15 As shown, the portions of the surfaces 110b of the adjacent light guide paths 110B may also be in contact with each other. In other words, the light absorbing portion 112 may not be provided between the peripheral portion of the surface 110b of the light guide path 110B and the peripheral portion of the surface 110b of the light guide path 110B adjacent to the light guide path 110B. By making the surfaces 110b of the adjacent light guide paths 110B contact each other in this way, the light La passing through the respective light guide paths 110B can reach the light receiving element PD in an overlapping state, and the intensity of the light can be increased.

[0157] Furthermore, the two modifications described above may be combined to make the aspect ratio different and the diameter of the light guide path 110 different for each position in the third direction Dz. These two modifications may also be applied to the second embodiment and the third embodiment described below.

[0158] (Second embodiment)

[0159] Next, the second embodiment is described. In the first embodiment, the light guide portion 102 includes the light guide path 110 and the light absorption portion 112, but in the second embodiment, a low refractive index portion is further included. In the second embodiment, description of the same parts as in the first embodiment is omitted.

[0160] Fig.16 as well as Fig.17 Schematic diagram of the light guide of the second embodiment. Fig.16 As shown, the light guide portion 102C of the light guide 100C of the second embodiment includes a light guide path 110, a light absorbing portion 112, and a low refractive index portion 114. The low refractive index portion 114 is a component whose refractive index of light L is lower than that of the light guide path 110. The refractive index of light L in the low refractive index portion 114 is preferably greater than 1.3 and less than 1.6. In addition, the transmittance of light L in the low refractive index portion 114 is preferably smaller than that of the light absorbing portion 112. The transmittance of light in the low refractive index portion 114 is preferably greater than 50% and less than 100%.

[0161] like Fig.17 As shown in FIG. 1 , the low refractive index portion 114 is provided for each light guide path 110, and each low refractive index portion 114 is provided so as to surround the periphery of the light guide path 110. That is, a plurality of low refractive index portions 114 are provided corresponding to the light guide paths 110. Fig.16 As shown, the low refractive index portion 114 is provided from the surface 102a to the surface 102b of the light guide portion 102. That is, it can be said that the surface 114a on the upper side of the low refractive index portion 114 constitutes the surface 102a of the light guide portion 102, and the surface 114b on the opposite side (lower side) of the surface 114a constitutes the surface 102b of the light guide portion 102. When the outer diameter of the low refractive index portion 114 is set to the diameter D3, the diameter D3 is preferably 1.0 times or more and 1.2 times or less relative to the diameter D1 of the light guide path 110. In addition, in the second embodiment, the light absorption portion 112 is provided in a manner surrounding the low refractive index portion 114. That is, the light absorption portion 112 is provided in the entire area of ​​the portion where the low refractive index portion 114 and the light guide path 110 are not provided in the light guide portion 102. Therefore, it can be said that the light guide path 110 of the second embodiment is formed in the portion surrounded by the low refractive index portion 114 in the light guide portion 102.

[0162] The material of the low refractive index portion 114 is arbitrary, but for example, it may be the same material as the light guide path 110. In this case, for example, Fig.11A The first organic material M1 described in the above is a material including a low molecular weight acrylic monomer having a π electron conjugated system and an oligomer having a siloxane bond with a low refractive index and difficult to photopolymerize. The molecular weight of the oligomer component is larger than that of the monomer. When the first organic material M1 is used to perform Fig.11A In step S12, the acrylic monomer component increases in the central part of the area irradiated with the light L, so the central part becomes a high refractive index, and the outer part in the radial direction becomes a low refractive index compared to the central part. That is, the central part becomes the light guide path 110, and the outer part in the radial direction becomes the low refractive index part 114, and the light guide path 110 and the low refractive index part 114 can be formed. However, this manufacturing method and material are just an example.

[0163] As described above, the light guide 102C further includes the low refractive index portion 114 having a lower refractive index than the light guide path 110. The low refractive index portion 114 surrounds each light guide path 110, and the light absorbing portion 112 surrounds each low refractive index portion 114. Fig.16 As shown, the light Lb incident into the light guide path 110 and irradiated to the outer peripheral surface of the light guide path 110 is reflected at the interface with the low refractive index portion 114 and travels to reach the light receiving element PD. In the case of the first embodiment, the low refractive index portion 114 is not provided, and therefore, the light Lb incident into the light guide path 110 and irradiated to the outer peripheral surface of the light guide path 110 is absorbed by the light absorbing portion 112 and does not reach the light receiving element PD. Therefore, in the first embodiment, it is possible to suppress the light L from a wide range from reaching the light receiving element PD. Since the light Lb does not reach the light receiving element PD, it is also considered that there is a situation where the intensity of the light is insufficient. In this case, if the low refractive index portion 114 is provided as in the second embodiment, the arrival of the light L (for example, the light Lc) from a wide range can be suppressed, and the light Lb is made to reach the light receiving element PD, and the insufficient intensity of the light can also be appropriately suppressed. Therefore, according to the second embodiment, the light L can be appropriately guided to the light receiving element PD.

[0164] (Variation Example)

[0165] Next, a modification of the second embodiment will be described. Fig.18 Schematic diagram of a light guide of a modified example. In the second embodiment, the low refractive index portion 114 surrounds the periphery of the light guide path 110, and the light absorbing portion 112 surrounds the periphery of the low refractive index portion 144. However, the structure of the light guide path 110, the low refractive index portion 114, and the light absorbing portion 112 is not limited to this structure. For example, Fig.18As shown in the light guide portion 102D of the light guide body 100D of the modified example, it can also be a structure having a light guide path 110, a low refractive index portion 114D and a light absorbing portion 112D. The low refractive index portion 114D is configured to surround the periphery of the light guide path 110, but does not surround the entire area of ​​the light guide path 110 in the third direction Dz, and only surrounds a part of the area of ​​the light guide path 110 in the third direction Dz. Specifically, a surface 114Db on the lower side of the low refractive index portion 114D is located at the same position as the surface 102b of the light guide portion 102, but a surface 114Da on the upper side of the low refractive index portion 114D is located on the side of the surface 102b compared to the surface 102a of the light guide portion 102, that is, on the lower side. The low refractive index portion 114D covers the periphery of the light guide path 110 in the area from the surface 114Da to the surface 114Db.

[0166] In addition, the light absorbing portion 112D is provided on the surface 114Da of the low refractive index portion 114D, and covers the periphery of the light guide path 110. The lower surface 112Db of the light absorbing portion 112D is in contact with the surface 114Da of the low refractive index portion 114D, and the upper surface 112Da is located at the same position as the surface 102a of the light guide portion 102. The light absorbing portion 112D covers the periphery of the light guide path 110 in the region from the surface 112Da to the surface 112Db. In addition, the length D4 of the light absorbing portion 112D in the third direction Dz is preferably not less than 0.3 times and not more than 1.0 times the length D2 of the light guide path 110 in the third direction Dz.

[0167] As described above, in the light guide portion 102D, the low refractive index portion 114D surrounds the respective light guide paths 110, and the light absorbing portion 112D is provided on the surface 114Da side of the low refractive index portion 114D. By configuring in this way, the light absorbing portion 112D on the upper side can absorb light Lc from a wide range, thereby suppressing the light from reaching the light absorbing portion 112D. In addition, the light Lb incident into the light guide path 110 and irradiated to the outer peripheral surface of the light guide path 110 is reflected on the inner peripheral surface of the low refractive index portion 114D and reaches the light receiving element PD, and the light Ld having a smaller incident angle than the light Lb (smaller incident angle relative to the surface 102a) is absorbed on the inner peripheral surface of the light absorbing portion 112D on the upper side, thereby suppressing the light L from a wide range from reaching.

[0168] Next, other modified examples of the second embodiment will be described. Fig.19 is a schematic diagram of a light guide of a modified example. Fig.19As shown, the light absorbing portion 112D of the light guide 100D may also include a first light absorbing portion 112D1 and a second light absorbing portion 112D2. The first light absorbing portion 112D1 is a portion provided on the surface 114Da of the low refractive index portion 114D in the light absorbing portion 112D. The second light absorbing portion 112D2 extends from the end 112D1a of the first light absorbing portion 112D1 that is connected to the light guide portion 102D to the end 112Dc toward the surface 102b side, that is, the light receiving element PD side. The second light absorbing portion 112D2 surrounds the periphery of the light guide path 110 from the end 112D1a to the end 112Dc. In addition, the second light absorbing portion 112D2 is surrounded by the low refractive index portion 114D from the end 112D1a to the end 112Dc. Since the second light absorbing portion 112D2 is not provided from the end portion 112Dc to the surface 102 b , the low refractive index portion 114D surrounds the light guiding path 110 .

[0169] The length D5 of the second light absorbing part 112D2 in the third direction Dz is preferably 0.2 to 1.0 times the length D2 of the light guide 110 . The inner diameter D6 of the second light absorbing part 112D2 is preferably 0.7 to 1.0 times the diameter D1 of the light guide 110 .

[0170] Like this, in Fig.19 In the example of FIG. 1 , the light absorbing portion 112D includes: a first light absorbing portion 112D1 provided on the surface 114Da side of the low refractive index portion 114D; and a second light absorbing portion 112D2 extending from an end 112D1a of the first light absorbing portion 112D1 on the light guiding portion 102D side toward the surface 102b side, and surrounding the periphery of the light guiding path 110. In the case of such a structure, the light Lb incident into the light guiding path 110 can be reflected at the low refractive index portion 114D below the second light absorbing portion 112D2 and reach the light receiving element PD. In addition, the light Ld having a smaller incident angle than the light Lb (smaller incident angle relative to the surface 102a) is absorbed at the inner peripheral surface of the second light absorbing portion 112D2, and is prevented from reaching the light receiving element PD.

[0171] (Third embodiment)

[0172] Next, the third embodiment will be described. The third embodiment is different from the first embodiment in that the light guide portion includes a selective light absorption portion 118. In the third embodiment, description of the same components as those of the first embodiment will be omitted.

[0173] Fig. 20 Schematic diagram of the light guide of the third embodiment. Fig. 20As shown, the light guide portion 102E of the light guide 100E of the third embodiment includes a light guide path 110, a light absorption portion 112, and a selective light absorption portion 118. In the third embodiment, the light guide path 110 transmits both the visible light L and the near-infrared light L. In addition, the light absorption portion 112 absorbs both the visible light L and the near-infrared light L. In addition, the selective light absorption portion 118 absorbs the visible light L, but transmits the near-infrared light L. The absorption rate of the visible light L of the selective light absorption portion 118 is higher than that of the light guide path 110, and the transmittance of the near-infrared light L is higher than that of the light absorption portion 112. The absorption rate of the visible light L of the selective light absorption portion 118 is preferably 70% to 100%, and more preferably 100%. The transmittance of the near-infrared light L of the selective light absorption portion 118 is preferably 70% to 100%, and more preferably 100%.

[0174] The selective light absorption portion 118 is provided for each light guide path 110 similarly to the low refractive index portion 114 of the second embodiment, and each selective light absorption portion 118 is provided so as to surround the periphery of the light guide path 110. That is, a plurality of the selective light absorption portions 118 are provided corresponding to the light guide paths 110. The selective light absorption portion 118 is provided from the surface 102a to the surface 102b of the light guide portion 102. That is, it can be said that the upper surface 118a of the selective light absorption portion 118 constitutes the surface 102a of the light guide portion 102, and the surface 118b on the opposite side (lower side) of the surface 118a constitutes the surface 102b of the light guide portion 102. When the outer diameter of the selective light absorption portion 118 is set to the diameter D7, the ratio of the length D2 to the diameter D7, that is, the aspect ratio of the selective light absorption portion 118 is smaller than the ratio of the length D2 to the diameter D1, that is, the aspect ratio of the light guide path 110. The aspect ratio of the selective light absorption portion 118 is preferably 0.2 times or more and 1.0 times or less relative to the aspect ratio of the light guide path 110. By setting such an aspect ratio, near-infrared light and visible light are appropriately received, and blood vessel patterns and fingerprints can be appropriately detected. In addition, the aspect ratio of the selective light absorption portion 118 is preferably 2 or more and preferably 20 or less.

[0175] The selective light absorbing portion 118 is made of an organic material, more specifically, a polymer material, for example, a polymer material containing a pigment dye that absorbs visible light.

[0176] In the third embodiment, the light absorbing portion 112 is provided so as to surround the selective light absorbing portion 118. That is, the light absorbing portion 112 is provided in the entire region of the portion where the selective light absorbing portion 118 and the light guide path 110 are not provided in the light guide portion 102. Therefore, it can be said that the light guide path 110 of the third embodiment is formed in the portion surrounded by the selective light absorbing portion 118 in the light guide portion 102.

[0177] As described above, the light guide 102E further includes the selective light absorption section 118. The selective light absorption section 118 has a higher absorption rate for visible light L than the light guide path 110, and a higher transmittance for near-infrared light L than the light absorption section 112. In addition, the selective light absorption section 118 surrounds the periphery of each light guide path 110, and the light absorption section 112 surrounds the periphery of each selective light absorption section 118. In the third embodiment, as Fig. 20 As shown, the visible light Lc and the near-infrared light L1c from other than the part to be detected are absorbed by the light absorbing portion 112, and can be suppressed from reaching the light receiving element PD. In addition, the visible light La and the near-infrared light L1a that are incident into the light guide path 110 but do not reach the inner peripheral surface of the selective light absorbing portion 118 pass through the light guide path 110 and reach the light receiving element PD. In addition, the visible light Lb with a smaller incident angle than the visible light La (smaller incident angle relative to the surface 102a) reaches the inner peripheral surface of the selective light absorbing portion 118 in the light guide path 110 and is absorbed by the selective light absorbing portion 118, and is suppressed from reaching the light receiving element PD. On the other hand, the visible light L1b with a smaller incident angle than the near-infrared light L1a reaches the inner peripheral surface of the selective light absorbing portion 118 in the light guide path 110, but is transmitted through the selective light absorbing portion 118 and reaches the light receiving element PD. That is, in the third embodiment, the depth of field of visible light can be deepened compared to the depth of field of near-infrared light, and fingerprint detection using visible light and blood vessel pattern detection using near-infrared light can be appropriately performed.

[0178] (Variation Example)

[0179] Next, a modification of the third embodiment will be described. Fig.21 Schematic diagram of a light guide of a modified example. In the third embodiment, the selective light absorption portion 118 surrounds the periphery of the light guide path 110, and the light absorption portion 112 surrounds the periphery of the selective light absorption portion 118. However, the structure of the light guide path 110, the selective light absorption portion 118, and the light absorption portion 112 is not limited to this structure. For example, Fig.21 As shown in the modified example of FIG. 1 , the selective light absorption portion 118 is configured to surround the light guide path 110, but does not surround the entire area of ​​the light guide path 110 in the third direction Dz, but only surrounds a portion of the light guide path 110 in the third direction Dz. That is, the lower surface 118b of the selective light absorption portion 118 is located at the same position as the surface 102b of the light guide portion 102, but the upper surface 118a of the selective light absorption portion 118 is located on the surface 102b side, that is, on the lower side, compared to the surface 102a of the light guide portion 102. The selective light absorption portion 118 surrounds the light guide path 110 in the area from the surface 118a to the surface 118b.

[0180] In addition, the light absorbing portion 112 is provided on the surface 112a of the selective light absorbing portion 118, and surrounds the periphery of the light guide path 110. The lower surface 112b of the light absorbing portion 112 contacts the surface 118a of the selective light absorbing portion 118, and the upper surface 112a is located at the same position as the surface 102a of the light guide portion 102. The light absorbing portion 112 surrounds the periphery of the light guide path 110 from the surface 112a to the surface 112b. In addition, the length D8 of the light absorbing portion 112 in the third direction Dz is preferably not less than 0.2 times and not more than 1.0 times the length D2 of the light guide path 110 in the third direction Dz.

[0181] Like this, in Fig.21 In the configuration of , the light Lb of visible light having a smaller incident angle than the light La of visible light (smaller incident angle relative to the surface 102a) reaches the inner peripheral surface of the selective light absorption portion 118 in the light guide path 110, is absorbed by the selective light absorption portion 118, and is suppressed from reaching the light receiving element PD. On the other hand, the light L1b of visible light having a smaller incident angle than the light L1a of near-infrared light reaches the inner peripheral surface of the selective light absorption portion 118 in the light guide path 110, but is transmitted through the selective light absorption portion 118 and reaches the light receiving element PD. That is, in this case, the depth of field of visible light can be deepened compared to the depth of field of near-infrared light, and fingerprint detection based on visible light and blood vessel pattern detection based on near-infrared light can be performed.

[0182] In addition, it should be understood that other effects brought about by the form described in this embodiment that can be clearly obtained from the description of this specification or can be appropriately imagined by a person skilled in the art are of course brought about by the present invention.

Claims

1. A method for manufacturing a light guide portion, characterized in that: include: Applying a first organic material on the substrate; irradiating light to a region of the first organic material coated on the substrate where a light guide path is formed; curing the first organic material in the region irradiated with light to form the light guide path made of the cured first organic material; removing the uncured first organic material from the substrate; Applying a second organic material to a region of the substrate where the light guide path is not formed; irradiating the second organic material on the substrate with light or heat to cure the second organic material to form a light absorbing portion; Disposing or adding a light-transmitting layer on the light-guiding portion to form a light-guiding body on the substrate; removing the substrate from the light guide; as well as The light guide is arranged on the sensor.

2. The method for manufacturing a light guide portion according to claim 1, wherein: The first organic material is a material including a low molecular weight acrylic monomer having a π electron conjugated system and an oligomer having a siloxane bond with a low refractive index and being difficult to photopolymerize. The oligomer has a molecular weight greater than that of the low molecular weight acrylic monomer, When curing the first organic material, the acrylic monomer increases in the central part of the area irradiated with light, so that the central part with a high refractive index becomes the light guide path, and the outer part in the radial direction of the central part with a low refractive index becomes a low refractive index part.

3. The method for manufacturing a light guide portion according to claim 1, wherein: , The light for curing the first organic material is ultraviolet light.

4. The method for manufacturing a light guide portion according to claim 1, wherein: , The light for curing the first organic material is collimated light.

5. The method for manufacturing a light guide portion according to claim 1, wherein: , The light that cures the first organic material is irradiated so that the light guide paths have different aspect ratios, which are ratios of lengths from one surface to the other surface to diameters of the light guide paths.

6. The method for manufacturing a light guide portion according to claim 1, wherein: Also includes: The selective light absorption portion is formed by irradiating light or heat to the polymer material on the substrate and curing the polymer material.

7. The method for manufacturing a light guide portion according to claim 6, wherein: , The polymer material contains a pigment or dye that absorbs visible light.

8. The method for manufacturing a light guide portion according to claim 6, wherein: , The selective light absorbing portion absorbs visible light but transmits infrared light.

9. The method for manufacturing a light guide portion according to claim 1, wherein: , The light absorbing portion absorbs visible light and infrared light.

10. The method for manufacturing a light guide portion according to claim 6, wherein: , The selective light absorption portion is formed thinner than the light absorption portion in a direction in which the first organic material and the second organic material are stacked on the substrate.

11. A method for manufacturing a light guide portion, characterized in that: include: Applying a first organic material on the substrate; irradiating light to a region of the first organic material coated on the substrate where a light guide path is formed; curing the first organic material in the region irradiated with light to form the light guide path made of the cured first organic material; removing the uncured first organic material from the substrate; Applying a second organic material to a region of the substrate where the light guide path is not formed; as well as The second organic material on the substrate is irradiated with light or heat to cure the second organic material, thereby forming a light absorbing portion.

12. A detection device, characterized in that: have: a plurality of light receiving elements for receiving light; and A light guide portion having a surface on one side arranged opposite to the light receiving element, The light guide portion includes a plurality of light guide paths provided from the one surface of the light guide portion to the other surface thereof, and a light absorbing portion having a higher light absorption rate than the light guide paths. When viewed from a direction in which the light receiving element and the light guiding portion overlap, a plurality of light guiding paths overlap with respect to one light receiving element. The plurality of light guide paths overlapping one light receiving element have different aspect ratios, wherein the aspect ratio is a ratio of a length from the surface of one side to the surface of the other side to a diameter. Each of the light guiding paths overlaps with the same light receiving element.

13. A detection device, characterized in that: have: a plurality of light receiving elements for receiving light; A light guide portion having a surface on one side arranged opposite to the light receiving element; and Multiple light-transmitting layers that transmit light, The light guide portion includes a plurality of light guide paths provided from the one surface of the light guide portion to the other surface thereof, and a light absorbing portion having a higher light absorption rate than the light guide paths. When viewed from a direction in which the light receiving element and the light guiding portion overlap, a plurality of light guiding paths overlap with respect to one light receiving element. The light guide portion further includes a low refractive index portion having a refractive index lower than that of the light guide path, The low refractive index portion surrounds each of the light guide paths, and the light absorbing portion surrounds each of the low refractive index portions. The light guide portion is sandwiched by a plurality of light-transmitting layers. The light-transmitting layer overlaps the plurality of light guide paths from the one surface to the other surface of the light guide portion.

14. A detection device, characterized in that: have: a plurality of light receiving elements for receiving light; and A light guide portion having a surface on one side arranged opposite to the light receiving element, The light guide portion includes a plurality of light guide paths provided from the one surface of the light guide portion to the other surface thereof, and a light absorbing portion having a higher light absorption rate than the light guide paths. When viewed from a direction in which the light receiving element and the light guiding portion overlap, a plurality of light guiding paths overlap with respect to one light receiving element. The low refractive index portion surrounds each of the light guide paths, and the light absorbing portion is provided on the other surface side of the low refractive index portion. The light absorbing portion is stacked on the low refractive index portion, The low refractive index portion is arranged on the light receiving element side.

15. A detection device, characterized in that: have: a plurality of light receiving elements for receiving light; and A light guide portion having a surface on one side arranged opposite to the light receiving element, The light guide portion includes a plurality of light guide paths provided from the one surface of the light guide portion to the other surface thereof, and a light absorbing portion having a higher light absorption rate than the light guide paths. When viewed from a direction in which the light receiving element and the light guiding portion overlap, a plurality of light guiding paths overlap with respect to one light receiving element. The light guide portion further includes a low refractive index portion having a refractive index lower than that of the light guide path, The low refractive index portion surrounds each of the light guide paths, and the light absorbing portion surrounds each of the low refractive index portions. The light guide portion has a plurality of light guide paths provided in the low refractive index portion, The surface of the low refractive index portion opposite to the light receiving element and a part of the inner surface of the light guide path are covered by the light absorbing portion. An end portion of the light absorbing portion in the light guiding path is located between an upper surface and a lower surface of the light guiding path.

16. A detection device, characterized in that: have: a plurality of light receiving elements for receiving light; and A light guide portion having a surface on one side arranged opposite to the light receiving element, The light guide portion includes a plurality of light guide paths provided from the one surface of the light guide portion to the other surface thereof, and a light absorbing portion having a higher light absorption rate than the light guide paths. When viewed from a direction in which the light receiving element and the light guiding portion overlap, a plurality of light guiding paths overlap with respect to one light receiving element. The light absorbing portion includes a first light absorbing portion that absorbs visible light but transmits infrared light, and a second light absorbing portion that absorbs visible light and infrared light. The first light absorbing portion is disposed between the light guiding path and the second light absorbing portion.

17. A detection device, characterized in that: have: a plurality of light receiving elements for receiving light; and A light guide portion having a surface on one side arranged opposite to the light receiving element, The light guide portion includes a plurality of light guide paths provided from the one surface of the light guide portion to the other surface thereof, and a light absorbing portion having a higher light absorption rate than the light guide paths. When viewed from a direction in which the light receiving element and the light guiding portion overlap, a plurality of light guiding paths overlap with respect to one light receiving element. The light absorbing part includes a first light absorbing part that absorbs visible light but transmits infrared light, and a second light absorbing part that absorbs visible light and infrared light. The first light absorbing portion is stacked on the second light absorbing portion, The first light absorbing portion is disposed on the light receiving element side.

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