Optical sensor

Abstract

To provide an optical sensor capable of obtaining a plurality of types of information by a plurality of wavelengths in a short time.SOLUTION: An optical sensor includes: a light receiving unit (sensor unit 610) that includes a plurality of pixels PX arranged in a matrix on a plane; a first pin hole layer 602 provided with a pin hole; a first transmission layer 604; a second pin hole layer 606 provided with a pin hole; a second transmission layer 608 that is arranged on the second pin hole layer and that transmits light; and a plurality of microlenses 610 belonging to a first group and a second group, the microlenses disposed at positions respectively overlapping the plurality of pixels on the second transmission layer. One of the plurality of microlenses belonging to the first group and the second group is a first wavelength selection unit 612 that transmits light in a first wavelength band, and at least one of the other of the plurality of microlenses belonging to the first group and the second group, the first transmission layer, and the second transmission layer is a second wavelength selection unit 614 that transmits light in a second wavelength band.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001] The present invention relates to an optical sensor.

Background Art

[0002] According to an optical sensor, by irradiating light in a specific wavelength band onto a measurement target and sensing reflected light or transmitted light from the measurement target, predetermined information can be obtained. For example, an optical sensor can irradiate visible light onto a finger and obtain fingerprint information by sensing the reflected light or transmitted light. Also, an optical sensor can irradiate near-infrared light onto a finger and obtain vein information by sensing the transmitted light.

[0003] Also, as a method of extracting only parallel light from scattered light, there is a method using a collimator (see Patent Document 1 below).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] An optical sensor can irradiate light in a plurality of wavelength bands onto a measurement target at intervals in sequence and sense reflected light or transmitted light from the measurement target respectively, thereby obtaining a plurality of types of information regarding the measurement target. However, doing so has a problem that it takes a long time to obtain all of the plurality of types of information.

[0006] The present invention has been made in view of the above problems, and an object thereof is to provide an optical sensor capable of obtaining a plurality of types of information with a plurality of wavelengths in a short time.

Means for Solving the Problems

[0007] An optical sensor according to one aspect of the present disclosure includes a light-receiving section that receives light from a target to be measured, comprising a plurality of pixels arranged in a matrix on a plane; a first pinhole layer having pinholes at positions overlapping with the plurality of pixels; a first light-transmitting layer disposed on the first pinhole layer and transmitting light; a second pinhole layer disposed on the first light-transmitting layer and having pinholes at positions overlapping with the plurality of pixels; a second light-transmitting layer disposed on the second pinhole layer and transmitting light; and a plurality of microlenses belonging to a first group and a plurality of microlenses belonging to a second group disposed on the second light-transmitting layer at positions overlapping with the plurality of pixels, wherein one of the plurality of microlenses belonging to the first group and the plurality of microlenses belonging to the second group is a first wavelength-selecting section that transmits light in a first wavelength band, and at least one of the other of the plurality of microlenses belonging to the first group and the plurality of microlenses belonging to the second group, the first light-transmitting layer, and the second light-transmitting layer is a second wavelength-selecting section that transmits light in a second wavelength band.

[0008] According to this disclosure, multiple types of information can be acquired in a short time using multiple wavelengths. [Brief explanation of the drawing]

[0009] [Figure 1] This is a plan view illustrating the general structure of an optical sensor. [Figure 2] This is a block diagram showing an example configuration of an optical sensor. [Figure 3] This is a circuit diagram showing an optical sensor. [Figure 4] This is a circuit diagram of a portion of the detection area. [Figure 5] Figure 1 is a partial cross-sectional view showing the cross-section of the VV line. [Figure 6] This is an overhead view of the microlens array according to the first embodiment. [Figure 7] This diagram shows a plan view and a cross-sectional view of an optical sensor, as well as a diagram illustrating its transmittance. [Figure 8]This diagram shows the time variation of the sensor output. [Figure 9] These are cross-sectional views of optical sensors according to modified examples 1 to 3. [Figure 10] These are plan views of the optical sensors according to modified examples 4 and 5. [Figure 11] This figure shows a method for manufacturing a microlens array using photolithography. [Figure 12] This figure shows a method for manufacturing a microlens array using an inkjet method. [Figure 13] This is a diagram illustrating a second embodiment. [Figure 14] This is a diagram illustrating the third embodiment. [Modes for carrying out the invention]

[0010] Embodiments of the present invention will be described below with reference to the drawings. However, the present invention can be implemented in various forms without departing from its spirit, and is not to be construed as being limited to the embodiments described below.

[0011] While drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment in order to clarify the explanation, these are merely examples and do not limit the interpretation of the present invention. In this specification and in each figure, elements having the same function as those described in previously shown figures are denoted by the same reference numerals, and redundant explanations may be omitted.

[0012] Furthermore, in the detailed description of the present invention, when defining the positional relationship between one component and another component, "above" and "below" include not only cases where the component is located directly above or directly below another component, but also cases where other components are interposed between them, unless otherwise specified.

[0013] [First Embodiment] FIG. 1 is a plan view showing an outline of an optical sensor 1 according to a first embodiment of the present invention. As shown in FIG. 1, the optical sensor 1 includes a resin substrate 100, a light receiving portion 10, a gate line driving circuit 15, a signal line selection circuit 16, a control circuit 26, a power supply circuit 28, a detection circuit 48, a flexible printed board 300, and a control board 400.

[0014] The control board 400 is electrically connected to the resin substrate 100 via the flexible printed board 300. The detection circuit 48 is provided on the flexible printed board 300. The control circuit 26 and the power supply circuit 28 are provided on the control board 400. The control circuit 26 supplies control signals to the light receiving portion 10, the gate line driving circuit 15, and the signal line selection circuit 16 to control the detection operation of the light receiving portion 10. The detection circuit 48 and the control circuit 26 are, for example, an IC (Integrated Circuit) or an FPGA (Field Programmable Gate Array). The power supply circuit 28 supplies a power supply voltage to the light receiving portion 10, the gate line driving circuit 15, and the signal line selection circuit 16.

[0015] The resin substrate 100 has a detection area DA and a frame area PA. The detection area DA is an area where the light receiving portion 10 is provided. The frame area PA is an area outside the detection area DA and is an area where the light receiving portion 10 is not provided.

[0016] The frame area PA has a bending area BA and a terminal area TA. The bending area BA and the terminal area TA are provided at one end of the frame area PA. Wiring connected to the detection area DA is arranged in the bending area BA and the terminal area TA. In the terminal area TA, the resin substrate 100 and the flexible printed board 300 are connected.

[0017] The light-receiving unit 10 comprises a plurality of pixels PX arranged in a matrix on a plane, and receives light from the object to be measured. Specifically, the light-receiving unit 10 comprises a plurality of pixels PX arranged in a matrix along a first direction Dx and a second direction Dy that is orthogonal to the first direction Dx in a plan view, and receives light from the object to be measured. The first direction Dx is the extension direction of the gate line GCL, and the second direction Dy is the extension direction of the signal line SGL. The plurality of pixels PX are arranged in a matrix in the detection region DA. The plurality of pixels PX include a photodiode, which is a light sensor 30 (see Figure 4), and each outputs an electrical signal corresponding to the light irradiated to it. Each pixel PX outputs an electrical signal corresponding to the light irradiated to it as a first detection signal Vdet to the signal line selection circuit 16. In addition, each pixel PX performs detection according to the gate drive signal Vgcl supplied from the gate line drive circuit 15.

[0018] The gate line drive circuit 15 and the signal line selection circuit 16 are provided in the frame region PA. Specifically, the gate line drive circuit 15 is provided in the region of the frame region PA that extends along the extension direction of the signal line SGL (second direction Dy). The signal line selection circuit 16 is provided in the region of the frame region PA that extends along the extension direction of the gate line GCL (first direction Dx), and is provided between the light receiving unit 10 and the bending region BA.

[0019] Figure 2 is a block diagram showing an example configuration of an optical sensor 1 according to the first embodiment of the present invention. As shown in Figure 2, the optical sensor 1 further includes a detection control unit 11 and a detection unit 40. Some or all of the functions of the detection control unit 11 are included in the control circuit 26. Also, some or all of the functions of the detection unit 40 are included in the control circuit 26.

[0020] The detection control unit 11 is a circuit that supplies control signals to the gate line drive circuit 15, the signal line selection circuit 16, and the detection unit 40, respectively, and controls their operation. The detection control unit 11 supplies various control signals such as the start signal STV, the clock signal CK, and the reset signal RST to the gate line drive circuit 15. The detection control unit 11 also supplies various control signals such as the selection signal ASW to the signal line selection circuit 16.

[0021] The gate line drive circuit 15 is a circuit that drives gate lines GCL based on various control signals. The gate line drive circuit 15 sequentially or simultaneously selects multiple gate lines GCL and supplies a gate drive signal Vgcl to the selected gate lines GCL. As a result, the gate line drive circuit 15 selects the pixel PX connected to the gate line GCL.

[0022] The signal line selection circuit 16 is a switch circuit that sequentially or simultaneously selects multiple signal lines SGL. The signal line selection circuit 16 is, for example, a multiplexer. Based on the selection signal ASW supplied from the detection control unit 11, the signal line selection circuit 16 connects the selected signal line SGL to the detection circuit 48. As a result, the signal line selection circuit 16 outputs the first detection signal Vdet of the pixel PX to the detection unit 40.

[0023] The detection unit 40 comprises a signal processing unit 44, a storage unit 45, a coordinate extraction unit 46, a detection timing control unit 47, and a detection circuit 48. The detection timing control unit 47 controls the signal processing unit 44, the coordinate extraction unit 46, and the detection circuit 48 to operate synchronously based on a control signal supplied from the detection control unit 11.

[0024] The detection circuit 48 is, for example, an analog front-end circuit (AFE). The detection circuit 48 is a signal processing circuit having at least the functions of a detection signal amplifier 42 and an A / D conversion unit 43. The detection signal amplifier 42 amplifies the first detection signal Vdet. The A / D conversion unit 43 converts the analog signal output from the detection signal amplifier 42 into a digital signal.

[0025] The signal processing unit 44 is a logic circuit that detects a predetermined physical quantity input to the light receiving unit 10 based on the output signal of the detection circuit 48. When the finger Fg is in contact with or close to the detection surface, the signal processing unit 44 can detect irregularities on the surface of the finger Fg or palm based on the signal from the detection circuit 48. The signal processing unit 44 can also detect information related to living organisms based on the signal from the detection circuit 48. This information related to living organisms includes, for example, the vascular image of the finger Fg or palm, pulse wave, pulse rate, blood oxygen saturation, etc. The signal processing unit 44 also calculates a signal ΔV, which is the difference between the first detection signal Vdet and the second detection signal Vdet-R.

[0026] The memory unit 45 temporarily stores the signals calculated by the signal processing unit 44. The memory unit 45 also stores information regarding past first detection signals Vdet, second detection signals Vdet-R, and difference signals ΔV. The memory unit 45 may be, for example, RAM (Random Access Memory), register circuits, etc.

[0027] The coordinate extraction unit 46 is a logic circuit that determines the detection coordinates of surface irregularities of the finger Fg, etc., when the signal processing unit 44 detects contact or proximity of the finger Fg. The coordinate extraction unit 46 is also a logic circuit that determines the detection coordinates of blood vessels in the finger Fg and palm. The coordinate extraction unit 46 generates two-dimensional information indicating the shape of surface irregularities of the finger Fg, etc., by combining the first detection signal Vdet output from each optical sensor 30 of the light receiving unit 10. The coordinate extraction unit 46 may also output the first detection signal Vdet and the second detection signal Vdet-R as sensor output Vo without calculating the detection coordinates.

[0028] Next, an example of the circuit configuration and operation of the optical sensor 1 will be described. Figure 3 is a circuit diagram showing the optical sensor 1. Figure 4 is a circuit diagram of a part of the detection area. In addition, Figure 4 also shows the circuit configuration of the detection circuit 48.

[0029] As shown in Figure 3, the light-receiving unit 10 has a plurality of partial detection regions PAA arranged in a matrix. Each of the plurality of partial detection regions PAA is provided with an optical sensor 30.

[0030] The gate line GCL extends in the first direction Dx and is connected to multiple partial detection regions PAA arranged in the first direction Dx. Furthermore, multiple gate lines GCL(1), GCL(2), ..., GCL(8) are arranged in the second direction Dy and are each connected to the gate line drive circuit 15. In the following description, when it is not necessary to distinguish between multiple gate lines GCL(1), GCL(2), ..., GCL(8), they will simply be referred to as gate line GCL. Also, while Figure 3 shows eight gate lines GCL for clarity, this is merely an example, and there may be M gate lines GCL (where M is 8 or more, for example, M=256) arranged.

[0031] The signal line SGL extends in the second direction Dy and is connected to the optical sensors 30 of multiple partial detection regions PAA arranged in the second direction Dy. Furthermore, the multiple signal lines SGL(1), SGL(2), ..., SGL(12) are arranged in the first direction Dx and are connected to the signal line selection circuit 16 and the reset circuit 17, respectively. In the following description, when it is not necessary to distinguish between the multiple signal lines SGL(1), SGL(2), ..., SGL(12), they will simply be referred to as signal line SGL.

[0032] Furthermore, for the sake of clarity, 12 signal lines SGL are shown, but this is merely an example, and the signal lines SGL may be arranged as N lines (N is 12 or more, for example, N=252). Also, the sensor resolution is, for example, 508 dpi (dots per inch), and the number of cells is 252 × 256. In addition, in Figure 3, the light receiving unit 10 is provided between the signal line selection circuit 16 and the reset circuit 17. However, it is not limited to this, and the signal line selection circuit 16 and the reset circuit 17 may be connected to the ends of the signal lines SGL in the same direction, respectively.

[0033] The gate line drive circuit 15 receives various control signals from the detection control unit 11, such as the start signal STV, the clock signal CK, and the reset signal RST1. Based on the various control signals, the gate line drive circuit 15 sequentially selects a plurality of gate lines GCL(1), GCL(2), ..., GCL(8) in a time-division manner. The gate line drive circuit 15 supplies a gate drive signal Vgcl to the selected gate line GCL. As a result, the gate drive signal Vgcl is supplied to a plurality of first switching elements Tr connected to the gate line GCL, and a plurality of partial detection regions PAA arranged in the first direction Dx are selected as detection targets.

[0034] The gate line drive circuit 15 may perform different drives for each detection mode of fingerprint detection and different types of biological information (pulse wave, pulse rate, vascular image, blood oxygen saturation, etc.). For example, the gate line drive circuit 15 may drive multiple gate lines GCLs together.

[0035] Specifically, the gate line drive circuit 15 may simultaneously select a predetermined number of gate lines GCL(1), GCL(2), ..., GCL(8) based on a control signal. For example, the gate line drive circuit 15 simultaneously selects gate line GCL(6) from the six gate lines GCL(1) and supplies a gate drive signal Vgcl. The gate line drive circuit 15 supplies the gate drive signal Vgcl to a plurality of first switching elements Tr via the six selected gate lines GCL. As a result, group regions PAG1 and PAG2, which include a plurality of partial detection regions PAA arranged in the first direction Dx and the second direction Dy, are selected as detection targets, respectively. The gate line drive circuit 15 drives a predetermined number of gate lines GCL in a bundle and sequentially supplies a gate drive signal Vgcl for each predetermined number of gate lines GCL. Hereinafter, when the positions of different group regions such as group regions PAG1 and PAG2 are not particularly distinguished, they will be referred to as group region PAG.

[0036] The signal line selection circuit 16 has a plurality of selection signal lines Lsel, a plurality of output signal lines Lout, and a second switching element TrS. Each of the plurality of second switching elements TrS is provided corresponding to a plurality of signal lines SGL. Six signal lines SGL(1), SGL (2), ..., SGL(6) are connected to a common output signal line Lout1. The six signal lines SGL(7), SGL(8), ..., SGL(12) are connected to a common output signal line Lout2. Output signal lines Lout1 and Lout2 are each connected to a detection circuit 48.

[0037] Here, signal lines SGL(1), SGL(2), ..., SGL(6) are designated as the first signal line block, and signal lines SGL(7), SGL(8), ..., SGL(12) are designated as the second signal line block. Multiple selection signal lines Lsel are each connected to the gate of a second switching element TrS contained in one signal line block. In addition, one selection signal line Lsel is connected to the gate of a second switching element TrS in multiple signal line blocks.

[0038] Specifically, the selection signal lines Lsel1, Lsel2, ..., Lsel6 are connected to the second switching elements TrS corresponding to the signal lines SGL(1), SGL(2), ..., SGL(6), respectively. In addition, selection signal line Lsel1 is connected to the second switching element TrS corresponding to signal line SGL(1) and the second switching element TrS corresponding to signal line SGL(7). Selection signal line Lsel2 is connected to the second switching element TrS corresponding to signal line SGL(2) and the second switching element TrS corresponding to signal line SGL(8).

[0039] The detection control unit 11 sequentially supplies the selection signal ASW to the selection signal line Lsel. As a result, the signal line selection circuit 16, through the operation of the second switching element TrS, sequentially selects the signal line SGL in a time-division manner within one signal line block. The signal line selection circuit 16 also selects one signal line SGL in each of multiple signal line blocks. With this configuration, the optical sensor 1 can reduce the number of integrated circuits (ICs) including the detection circuit 48, or the number of terminals of the ICs.

[0040] The signal line selection circuit 16 may also bundle multiple signal lines SGL and connect them to the detection circuit 48. Specifically, the detection control unit 11 simultaneously supplies a selection signal ASW to the selected signal line Lsel. As a result, the signal line selection circuit 16, through the operation of the second switching element TrS, selects multiple signal lines SGL (for example, six signal lines SGL) in one signal line block and connects the multiple signal lines SGL to the detection circuit 48. As a result, the signals detected in each group region PAG are output to the detection circuit 48. In this case, signals from multiple partial detection regions PAA (optical sensors 30) are integrated and output to the detection circuit 48 on a group region PAG basis.

[0041] The operation of the gate line drive circuit 15 and the signal line selection circuit 16 allows detection to be performed for each group region PAG, thereby improving the intensity of the first detection signal Vdet obtained in a single detection, and thus improving sensor sensitivity. Furthermore, the time required for detection can be shortened. As a result, the optical sensor 1 can perform detection repeatedly in a short time, improving the signal-to-noise ratio, and enabling accurate detection of temporal changes in biological information such as pulse waves.

[0042] The reset circuit 17 includes a reference signal line Lvr, a reset signal line Lrst, and a third switching element TrR. The third switching element TrR is provided corresponding to a plurality of signal lines SGL. The reference signal line Lvr is connected to either the source or the drain of the plurality of third switching elements TrR. The reset signal line Lrst is connected to the gate of the plurality of third switching elements TrR.

[0043] The detection control unit 11 supplies a reset signal RST2 to the reset signal line Lrst. This turns on multiple third switching elements TrR, and multiple signal lines SGL are electrically connected to the reference signal line Lvr. The power supply circuit 28 supplies a reference signal COM to the reference signal line Lvr. This supplies the reference signal COM to the additional capacitance Cad (see Figure 4) included in multiple partial detection regions PAA.

[0044] As shown in Figure 4, the partial detection region PAA includes the optical sensor 30, the additional capacitance Cad, and the first switching element Tr. In Figure 4, two gate lines GCL(m) and GCL(m+1) are shown among the multiple gate lines GCL, aligned in the second direction Dy. Also, two signal lines SGL(n) and SGL(n+1) are shown among the multiple signal lines SGL, aligned in the first direction Dx. The partial detection region PAA is the region enclosed by the gate lines GCL and the signal lines SGL. The first switching element Tr is provided corresponding to the optical sensor 30. The first switching element Tr is composed of a thin-film transistor TFT (see Figure 5), and in this example, it is composed of an n-channel MOS (Metal Oxide Semiconductor) type TFT (Thin Film Transistor).

[0045] The gates of the first switching elements Tr belonging to the multiple partial detection regions PAA aligned in the first direction Dx are connected to the gate line GCL. The sources of the first switching elements Tr belonging to the multiple partial detection regions PAA aligned in the second direction Dy are connected to the signal line SGL. The drains of the first switching elements Tr are connected to the cathode and additional capacitance Cad of the optical sensor 30.

[0046] The anode of the light sensor 30 is supplied with a sensor power signal VDDSNS from the power supply circuit 28. In addition, the signal line SGL and the additional capacitor Cad are supplied with a reference signal COM from the power supply circuit 28, which becomes the initial potential of the signal line SGL and the additional capacitor Cad.

[0047] When light is shone onto the partial detection region PAA, a current corresponding to the amount of light flows through the light sensor 30, causing charge to accumulate in the additional capacitor Cad. When the first switching element Tr is turned on, a current flows through the signal line SGL according to the charge accumulated in the additional capacitor Cad. The signal line SGL is connected to the detection circuit 48 via the second switching element TrS of the signal line selection circuit 16. As a result, the optical sensor 1 can detect a signal corresponding to the amount of light shone onto the light sensor 30 for each partial detection region PAA or each group region PAG.

[0048] The detection signal amplification unit 42 of the detection circuit 48 converts the current fluctuations supplied from the signal line SGL into voltage fluctuations and amplifies them. A reference potential Vref with a fixed potential is input to the non-inverting input (+) of the detection signal amplification unit 42. The signal line SGL is connected to the inverting input terminal (-) when the output switch SSW is ON. The same signal as the reference signal COM is input as the reference potential Vref. The detection signal amplification unit 42 also has a capacitive element Cb and a reset switch RSW. When the signal readout for one line is complete, the reset switch RSW is turned ON, and the charge of the capacitive element Cb is reset.

[0049] Next, the cross-sectional configuration of the optical sensor 1 will be described. Figure 5 is a partial cross-sectional view showing the VV line cross-section of Figure 1 in the first embodiment. Note that the microlens array 600 (described later) is omitted in Figure 5. Also, in Figure 5, a part of the detection region DA and a part of the frame region PA are shown in cross-sectional view. As mentioned above, the detection region DA has multiple pixels PX, and the frame region PA has a bent region BA and a terminal region TA. Each pixel PX has a corresponding lower electrode 210 and a corresponding thin-film transistor TFT. The circuit layer CL has a barrier inorganic film 110 to an inorganic insulating film 180, and the organic photoelectric conversion layer OPL has a lower electrode 210 to an upper electrode 230.

[0050] Note that while Figure 5 shows the cross-section in the second direction Dy, the same cross-sectional structure as in Figure 4 is observed when the detection region DA is cut in the first direction Dy. Also, in Figure 5, some hatching of certain layers has been omitted to make the cross-sectional structure easier to see.

[0051] From here, the laminated structure of the resin substrate 100 to the sealing film 260 will be described in order from the bottom layer. First, the circuit layer CL provided on the resin substrate 100 will be described.

[0052] A barrier inorganic film 110 is laminated on a resin substrate 100. The resin substrate 100 is made of polyimide. However, the resin substrate 100 may be made of other resin materials as long as it is a substrate with sufficient flexibility for use as a sheet-type optical sensor. On the other hand, the barrier inorganic film 110 has a three-layer laminated structure consisting of a first inorganic film 111 (e.g., a silicon oxide film), a second inorganic film 112 (e.g., a silicon nitride film), and a third inorganic film 113 (a silicon oxide film). The first inorganic film 111 is provided to improve adhesion to the substrate, the second inorganic film 112 as a blocking film for moisture and impurities from the outside, and the third inorganic film 113 as a blocking film to prevent hydrogen atoms contained in the second inorganic film 112 from diffusing towards the semiconductor layer 131, but the structure is not limited to this. Further lamination is also possible, and it may be a single layer or a double layer.

[0053] The additional film 120 may be formed in accordance with the area where the thin-film transistor TFT described later will be formed. The additional film 120 can suppress changes in the characteristics of the thin-film transistor TFT due to light intrusion from the back surface of the channel of the thin-film transistor TFT, or it can be formed from a conductive material and a predetermined potential can be applied to give the thin-film transistor TFT a back gate effect. Here, after forming the first inorganic film 111, the additional film 120 is formed in an island shape in accordance with the area where the thin-film transistor TFT will be formed, and then the second inorganic film 112 and the third inorganic film 113 are stacked to encapsulate the additional film 120 in the barrier inorganic film 110. However, this is not limited to this, and the additional film 120 may be formed first on the resin substrate 100, and then the barrier inorganic film 110 may be formed.

[0054] A thin-film transistor TFT is formed on the barrier inorganic film 110 for each pixel PX. The thin-film transistor TFT has a semiconductor layer 131, a gate electrode 132, a source electrode 133, and a drain electrode 134. Although only an Nch transistor is shown here, using a polysilicon thin-film transistor as an example, a Pch transistor may also be formed simultaneously. The semiconductor layer 131 of the thin-film transistor TFT has a structure in which a low-concentration impurity region or an intrinsic semiconductor region is provided between the channel region and the source / drain region. The gate electrode 132 is the part in each pixel PX where the gate line GCL is electrically connected to the semiconductor layer 131. Similarly, the source electrode 133 is the part in each pixel PX where the signal line SGL is electrically connected to the semiconductor layer 131.

[0055] A gate insulating film 140 is provided between the semiconductor layer 131 and the gate electrode 132. Here, a silicon oxide film is used as the gate insulating film 140. The gate electrode 132 is part of the first wiring layer W1 formed from MoW. In addition to the gate electrode 132, the first wiring layer W1 has a first retaining capacitance line CsL1. A portion of the retaining capacitance Cs is formed between the first retaining capacitance line CsL1 and the semiconductor layer 131 (source / drain region) via the gate insulating film 140.

[0056] An interlayer insulating film 150 is formed on the gate electrode 132. The interlayer insulating film 150 has a structure in which a silicon nitride film and a silicon oxide film are laminated. In the area corresponding to the bending region BA, the barrier inorganic film 110 to the interlayer insulating film 150 are removed by patterning. In the area corresponding to the bending region BA, the polyimide that constitutes the resin substrate 100 is exposed. Note that when the barrier inorganic film 110 is removed by patterning, the surface of the polyimide may be partially eroded, resulting in film reduction.

[0057] Wiring patterns are formed in the layers beneath the stepped portions at the edges of the interlayer insulating film 150 and the barrier inorganic film 110. When the routing wiring RW crosses the stepped portions, it passes over the wiring patterns. Between the interlayer insulating film 150 and the barrier inorganic film 110, there is, for example, a gate electrode 132, and between the barrier inorganic film 110 and the resin substrate 100, there is, for example, an additional film 120, so these layers are used to form the wiring patterns.

[0058] A second wiring layer W2 is formed on the interlayer insulating film 150, including a source electrode 133, a drain electrode 134, and a portion that will become a routing wiring RW. Here, a three-layer laminated structure of Ti, Al, and Ti is adopted. The interlayer insulating film 150 is used to form the other part of the retaining capacitance Cs by the first retaining capacitance line CsL1 (part of the first wiring layer W1) and the second retaining capacitance line CsL2 (part of the second wiring layer W2). The routing wiring RW extends from the bending region BA to the terminal region TA, forming a terminal portion T for connecting a flexible printed circuit board 300, etc.

[0059] Furthermore, since the routing wiring RW is formed to cross the bending region BA and reach the terminal portion T, it crosses the stepped portion of the interlayer insulating film 150 and the barrier inorganic film 110. As mentioned above, a wiring pattern is formed in the stepped portion, for example, by an additional film 120. Therefore, even if the routing wiring RW is interrupted in the recess of the step, an electrical connection can be maintained by making contact with the wiring pattern.

[0060] A planarization film 160 is provided so as to cover the source electrode 133, the drain electrode 134, and the interlayer insulating film 150. The planarization film 160 is made of a resin such as photosensitive acrylic because it has superior surface flatness compared to inorganic insulating materials formed by CVD (Chemical Vapor Deposition) or the like. The planarization film 160 is removed in the pixel contact area 170, the upper electrode contact area 171, the bending area BA, and the terminal area TA.

[0061] A transparent conductive film 190 made of indium tin oxide (ITO) is formed on the planarized film 160 for each pixel PX. The transparent conductive film 190 includes a first transparent conductive film 191 and a second transparent conductive film 192 that are separated from each other.

[0062] The first transparent conductive film 191 is electrically connected to the second wiring layer W2, whose surface is exposed by the removal of the planarization film 160, at the pixel contact portion 170. On the other hand, the second transparent conductive film 192 is provided below the lower electrode 210 (further below the inorganic insulating film 180), next to the pixel contact portion 170. The inorganic insulating film 180 (silicon nitride film) is then provided on top of the transparent conductive film 190 and the planarization film 160, covering the first transparent conductive film 191 except for the opening in the pixel contact portion 170.

[0063] The second transparent conductive film 192, the inorganic insulating film 180, and the lower electrode 210 overlap in a plan view, and these together form an additional capacitance Cad.

[0064] Furthermore, the transparent conductive film 190 may also be formed on the surface of the terminal portion T, forming a third transparent conductive film 193. The third transparent conductive film 193 formed on the surface of the terminal portion T may be provided for the purpose of protecting the exposed wiring portion from damage in a process after the formation of the third transparent conductive film 193.

[0065] A lower electrode 210 is provided on the inorganic insulating film 180 for each pixel PX, so as to conduct electricity to the drain electrode 134 through an opening in the inorganic insulating film 180 at the pixel contact portion 170. The lower electrode 210 is formed as a reflective electrode and has a three-layer stacked structure of indium zinc oxide film, Ag film, and indium zinc oxide film. Here, an indium tin oxide film may be used instead of the indium zinc oxide film. The lower electrode 210 extends laterally from the pixel contact portion 170 and reaches above the thin-film transistor TFT.

[0066] An organic material layer 220 is provided on the lower electrode 210. The organic material layer 220 includes, from bottom to top, a lower carrier transport layer 221, an organic light-receiving layer 222, and an upper carrier transport layer 223. When a surface irradiation type structure is adopted, the lower carrier transport layer 221 is used as a hole transport layer and the upper carrier transport layer 223 as an electron transport layer. When a back-illumination type structure is adopted, the lower carrier transport layer 221 is used as an electron transport layer and the upper carrier transport layer 223 as a hole transport layer. The organic light-receiving layer 222 may be formed by vapor deposition or by coating on a solvent dispersion. Here, it is formed as a solid layer covering the entire surface of the detection region DA, but this is not limited to this.

[0067] An upper electrode 230 is formed on the organic material layer 220, common to each pixel PX. When a surface-illuminated structure is adopted, the upper electrode 230 needs to be transparent. Here, after forming PEDOT:PSS on the surface in contact with the organic material layer 220, the upper electrode 230 is formed as a thin film that allows incident light to pass through, using a metallic material such as Ag or Al. The upper electrode 230 is formed extending from the organic material layer 220 provided in the detection region DA to the upper electrode contact portion 171 provided in the frame region PA. At the upper electrode contact portion 171, it is electrically connected to the routing wiring RW of the second wiring layer W2, and finally led out to the terminal portion T.

[0068] A sealing film 260 is formed on the upper electrode 230. One of the functions of the sealing film 260 is to protect the organic material layer 220 from moisture and other substances entering from the outside, and a high gas barrier function is required. Here, a laminated structure including a silicon nitride film is used, consisting of a silicon nitride film, an organic resin, and another silicon nitride film. A silicon oxide film or an amorphous silicon layer may be provided between the silicon nitride film and the organic resin, partly for the purpose of improving adhesion. However, since the film is provided on the light-receiving surface side, it is preferable to use a material that does not have an effect such as absorption on light of the wavelength to be detected.

[0069] Next, the microlens array 600 according to the first embodiment will be described with reference to Figures 6 to 7(c). Figure 6 is an overhead view of the microlens array 600. Figure 7(a) is a plan view of the optical sensor 1 to illustrate the wavelength of transmitted light. Figure 7(b) is a schematic diagram showing the VII-VII cross section of Figure 7. Figure 7(c) is a diagram to illustrate transmittance. In the figure, "Red" indicates the transmittance of the first wavelength selection section 612 of the microlens array 600, "NIR" indicates the transmittance of the second wavelength selection section 614 of the microlens array 600, and "colorless" indicates the transmittance of the first transmission layer 604 and the second transmission layer 608 of the microlens array 600.

[0070] In Figure 7(a), only a portion of the optical sensor 1 (a 4x5 area) is shown, and the wavelength of light passing through the microlens array 600 is represented by hatching. In Figure 7(b), the layers shown in Figure 5 are omitted to show the positional relationship between the microlens 610, the pinhole, and the pixel PX, and only the pixel PX is shown for the sensor section 601.

[0071] The optical sensor 1 includes a microlens array 600 and a sensor unit 601, the sensor unit 601 including the resin substrate 100 and sealing film 260 as shown in Figure 5. The microlens array 600 includes a first pinhole layer 602, a first transparent layer 604, a second pinhole layer 606, a second transparent layer 608, and a plurality of microlenses 610. The microlens array 600 and the sensor unit 601 are bonded together by a transparent adhesive layer (not shown), such as an optical clear adhesive (OCA). Furthermore, as will be explained in the manufacturing method described later, a transparent substrate 1100 or a resin layer may be placed between the second transparent layer 608 and the plurality of microlenses 610.

[0072] The first pinhole layer 602 has pinholes positioned to overlap with each of the multiple pixels PX. Specifically, for example, the first pinhole layer 602 is made of a material that shields visible light and infrared light. The first pinhole layer 602 has a thickness of, for example, 2 μm and has pinholes positioned to overlap with each pixel PX in a plan view. The diameter of the pinholes provided in the first pinhole layer 602 is, for example, 5 μm.

[0073] The first transparent layer 604 is placed on top of the first pinhole layer 602 and transmits light. Specifically, for example, the first transparent layer 604 is formed on top of the first pinhole layer 602 from a material that transmits the entire wavelength range of visible light and infrared light. The first transparent layer 604 also fills the pinholes in the first pinhole layer 602 and has a thickness of, for example, 20 μm.

[0074] The second pinhole layer 606 is provided with pinholes at positions that overlap with each of the multiple pixels PX, and is placed on top of the first transparent layer 604. Specifically, for example, the second pinhole layer 606 is made of a material that shields visible light and infrared light. The second pinhole layer 606 has a thickness of, for example, 2 μm and has pinholes at positions that overlap with each pixel PX in a plan view. The diameter of the pinholes provided in the second pinhole layer 606 is, for example, 10 μm.

[0075] The second transparent layer 608 is placed on top of the second pinhole layer 606 and transmits light. Specifically, for example, the second transparent layer 608 is formed on top of the second pinhole layer 606 from a material that transmits the entire wavelength range of visible light and infrared light. The second transparent layer 608 also fills the pinholes in the second pinhole layer 606 and has a thickness of, for example, 30 μm.

[0076] Multiple microlenses 610 are positioned on the second transmission layer 608, each overlapping with multiple pixels PX. Specifically, for example, the multiple microlenses 610 have a flattened spherical shape and collect incident visible light and infrared light. The collected light passes through the second transmission layer 608, the pinhole of the second pinhole layer 606, the first transmission layer 604, and the pinhole of the first pinhole layer 602 in that order, and illuminates the pixels PX.

[0077] Furthermore, the plurality of microlenses 610 include a plurality of microlenses 610 belonging to the first group and a plurality of microlenses 610 belonging to the second group. In the first embodiment, the first group and the second group are arranged in a planar configuration. Specifically, for example, as shown in Figures 6 and 7(a), the plurality of microlenses 610 belonging to the first group are arranged in a line toward the second direction Dy. Similarly, the plurality of microlenses 610 belonging to the second group are arranged in a line toward the second direction Dy. The plurality of microlenses 610, 612 belonging to the first group and the plurality of microlenses 610 belonging to the second group are arranged alternately in pairs of two rows toward the first direction Dx.

[0078] In this disclosure, one of the plurality of microlenses 610 belonging to the first group and the plurality of microlenses 610 belonging to the second group is a first wavelength selector 612 that transmits light in the first wavelength band. The other of the plurality of microlenses 610 belonging to the first group and the plurality of microlenses 610 belonging to the second group, and at least one of the first transmission layer 604 and the second transmission layer 608 is a second wavelength selector 614 that transmits light in the second wavelength band.

[0079] In the first embodiment, the plurality of microlenses 610 belonging to the first group constitute a first wavelength selector 612, and the plurality of microlenses 610 belonging to the second group constitute a second wavelength selector 614. Specifically, for example, the plurality of microlenses 610 belonging to the first group constitute a first wavelength selector 612 that transmits only light in the first wavelength band (for example, 640 nm to 680 nm centered at 660 nm). The plurality of microlenses 610 belonging to the second group constitute a second wavelength selector 614 that transmits only light in the second wavelength band (for example, 830 nm to 870 nm centered at 850 nm). In Figure 7(c), "Red" indicates the transmittance of the first wavelength selector 612, "NIR" indicates the transmittance of the second wavelength selector 614, and "Colorless" indicates the transmittance of the first and second transmission layers 604 and 608.

[0080] As described above, the multiple microlenses 610 focus the incident light, and the focused light passes through each pinhole in the first pinhole layer 602 and each pinhole in the second pinhole layer 606. That is, of the light incident on the partial detection area PAA of pixel PX, the component incident from an oblique direction is blocked, and only the component incident from a vertical direction reaches the partial detection area PAA. Therefore, the microlens array 600 functions as a collimator.

[0081] Furthermore, only light in the first wavelength band (for example, 640 nm to 680 nm, centered at 660 nm) reaches the partial detection region PAA that overlaps with the first wavelength selection unit 612 in a plan view. Only light in the second wavelength band (for example, 830 nm to 870 nm, centered at 850 nm) reaches the partial detection region PAA that overlaps with the second wavelength selection unit 614 in a plan view. As a result, the optical sensor 1 according to the first embodiment can acquire multiple types of information at multiple wavelengths.

[0082] As described above, the optical sensor 1 having a first wavelength selection unit 612 and a second wavelength selection unit 614 can acquire multiple types of information at multiple wavelengths in a short time. In the prior art, it was possible to acquire multiple types of information about a measurement target by irradiating the measurement target with light of multiple wavelength bands at intervals and sensing the reflected and transmitted light from the measurement target, respectively. However, according to this disclosure, multiple types of information can be acquired at multiple wavelengths in a short time.

[0083] Figure 8(a) is a diagram showing the time change of the sensor output in the prior art (time-division multiplexing), and Figure 8(b) is a diagram showing the time change of the sensor output in this disclosure. In Figures 8(a) and 8(b), the vertical axis is the sensor output Vo, and the horizontal axis is time. Here, the coordinate extraction unit 46 outputs a first detection signal Vdet as the sensor output Vo.

[0084] As shown in Figure 8(a), in the conventional technology, an LED emitting 850nm light and an LED emitting 660nm light are alternately lit. The sensor output Vo begins to increase as the LED is turned ON, increases to a certain voltage corresponding to the light intensity of the LED, and then stabilizes. Subsequently, the sensor output Vo output from all partial detection regions PAA is acquired once (or a predetermined number of times). Then, the power supply circuit 28 turns the LEDs OFF at the timing when a reference signal COM is supplied to the additional capacitance Cad (see Figure 4) included in the multiple partial detection regions PAA.

[0085] When the LED is turned OFF, the sensor output Vo gradually decreases, and after a certain period of time, it returns to the initial output voltage value (e.g., 0V). In order to acquire multiple types of information, it is necessary to avoid mixing sensor outputs Vo from 850nm and 660nm light. Therefore, in order to turn on the LED emitting 660nm light, a certain period of time is required after the LED emitting 850nm light is turned OFF. Similarly, in order to turn on the LED emitting 850nm light, a certain period of time is required after the LED emitting 660nm light is turned OFF. Consequently, conventional technology requires time to switch between LEDs.

[0086] On the other hand, according to this disclosure, as shown in Figure 8(b), even if an LED emitting 660nm light and an LED emitting 850nm light are kept ON at the same time, multiple types of information can be acquired based on the sensor output Vo of the pixel PX corresponding to the first wavelength selection unit 612 and the sensor output Vo of the pixel PX corresponding to the second wavelength selection unit 614. Therefore, the detection accuracy per unit of time can be improved.

[0087] Furthermore, by using an LED that emits both 660nm and 850nm light (for example, a white LED), it becomes unnecessary to provide LEDs that emit light at individual wavelengths.

[0088] In the above explanation, we used the example where the first wavelength band is shorter than the second wavelength band, the first wavelength band is red light, and the second wavelength band is infrared light. However, the bandwidths of the first and second wavelength bands can be set as appropriate depending on the application of the optical sensor 1.

[0089] Furthermore, the above description explains the case where a combination of one microlens 610, one pinhole in the first pinhole layer 602, and one pinhole in the second pinhole layer 606 (hereinafter referred to as a set of microlenses 610, etc.) corresponds to one pixel PX, but it is not limited to this. For example, a set of microlenses 610, etc. may correspond to four pixels PX arranged in two rows and two columns. Alternatively, four sets of microlenses 610, etc. arranged in two rows and two columns may correspond to one pixel PX.

[0090] [Example 1] Figure 9(a) is a cross-sectional view of the optical sensor 1 according to modification 1 of the first embodiment, and corresponds to Figure 7(b) of the first embodiment described above. The same configuration as in the first embodiment described above will not be explained.

[0091] In Modification 1, the pinholes in the first pinhole layer 602 located at positions corresponding to the multiple microlenses 610 belonging to the first group have a smaller diameter than the pinholes in the first pinhole layer 602 located at positions corresponding to the multiple microlenses 610 belonging to the second group. As a result, the pixels PX located at positions corresponding to the multiple microlenses 610 belonging to the first group receive light incident at a higher angle of incidence to the surface of the optical sensor 1 than the pixels PX located at positions corresponding to the multiple microlenses 610 belonging to the second group. In other words, a set of microlenses 610 belonging to the first group has higher collimation performance but lower transmittance than a set of microlenses 610 belonging to the second group.

[0092] Generally, fingerprint authentication and vein authentication require different resolutions because they involve different subject shapes. For example, fingerprint authentication requires a resolution of 500 dpi. Vein authentication requires a lower resolution because veins are thicker than fingerprints. Also, a pair of microlenses such as the 610 has higher transmittance as its collimation performance decreases. Therefore, it is preferable to design collimators for capturing fingerprints to have high collimation performance, and collimators for capturing veins, which experience greater light attenuation, to have lower collimation performance.

[0093] According to Modification 1, a pair of microlenses 610 belonging to the first group can have higher collimation performance than a pair of microlenses 610 belonging to the second group. Therefore, Modification 1, in which the first wavelength band is set shorter than the second wavelength band, a pair of microlenses 610 belonging to the first group is used for fingerprint authentication, and a pair of microlenses 610 belonging to the first group is used for vein authentication, is optimal when fingerprint authentication and vein authentication are performed simultaneously.

[0094] [Differentiation 2] Figure 9(b) is a cross-sectional view of the optical sensor 1 according to a modified example 2 of the first embodiment, and corresponds to Figure 7(b) of the first embodiment described above. The same configuration as in the first embodiment described above will not be explained.

[0095] In Modification 1, the multiple microlenses 610 belonging to the first group have a larger diameter and the same height as the multiple microlenses 610 belonging to the second group. According to the configuration of Modification 2, the pixels PX located at positions corresponding to the multiple microlenses 610 belonging to the first group receive light incident at a higher angle of incidence to the surface of the optical sensor 1 than the pixels PX located at positions corresponding to the multiple microlenses 610 belonging to the second group. Therefore, Modification 2, which, like Modification 1, sets the first wavelength band shorter than the second wavelength band, uses one set of microlenses 610 belonging to the first group for fingerprint authentication, and uses one set of microlenses 610 belonging to the first group for vein authentication, is optimal when performing fingerprint authentication and vein authentication simultaneously.

[0096] [Difference 3] Figure 9(c) is a cross-sectional view of the optical sensor 1 according to a modified example 2 of the first embodiment, and corresponds to Figure 7(b) of the first embodiment described above. The same configuration as in the first embodiment described above will not be explained.

[0097] In Modification 3, the multiple microlenses 610 belonging to the first group are shorter in height and have the same diameter as the multiple microlenses 610 belonging to the second group. According to the configuration of Modification 3, the pixels PX located at positions corresponding to the multiple microlenses 610 belonging to the first group receive light incident at a higher angle of incidence to the surface of the optical sensor 1 than the pixels PX located at positions corresponding to the multiple microlenses 610 belonging to the second group. Therefore, Modification 3, which sets the first wavelength band shorter than the second wavelength band, uses one set of microlenses 610 belonging to the first group for fingerprint authentication, and uses another set of microlenses 610 belonging to the first group for vein authentication, is optimal when fingerprint authentication and vein authentication are performed simultaneously. Note that the configurations of Modifications 1 to 3 may be applied in combination.

[0098] [Differentiation Example 4] Figure 10(a) is a plan view of the optical sensor 1 according to modification 4 of the first embodiment, and corresponds to Figure 7(a) of the first embodiment described above. The same configuration as in the first embodiment described above will not be explained.

[0099] In Modification 4, microlenses 610 belonging to the second group are arranged on all four sides of the microlenses 610 belonging to the first group. Specifically, the multiple microlenses 610 belonging to the first group are arranged in odd-numbered rows and odd-numbered columns. The multiple microlenses 610 belonging to the second group are arranged in even-numbered rows and even-numbered columns. In Modification 4 as well, the optical sensor 1 can acquire multiple types of information using multiple wavelengths. The arrangement layout of the microlenses 610 belonging to the first group and the microlenses 610 belonging to the second group is not limited to the layout in Modification 4 and can be changed as appropriate.

[0100] [Difference 5] Figure 10(b) is a plan view of the optical sensor 1 according to modification 5 of the first embodiment, and corresponds to Figure 7(a) of the first embodiment. The same configuration as in the first embodiment will not be described.

[0101] In modified example 5, the microlens 610 further includes a plurality of microlenses 610 belonging to a third group, which are positioned to overlap with a plurality of pixels PX on the second transmission layer 608. Specifically, the microlens 610 includes a plurality of microlenses 610 belonging to a first group, a plurality of microlenses 610 belonging to a second group, and a plurality of microlenses 610 belonging to a third group. As described above, the plurality of microlenses 610 belonging to the first group constitute a first wavelength selector 612, and the plurality of microlenses 610 belonging to the second group constitute a second wavelength selector 614. The plurality of microlenses 610 belonging to the third group constitute a third wavelength selector 1000 that transmits light in the third wavelength band. The third wavelength selector 1000 is, for example, a resin that transmits only light in the third wavelength band (for example, from 535 nm to 575 nm, centered around 555 nm).

[0102] Multiple microlenses 610 belonging to the first group are arranged in a line toward the second direction Dy. Multiple microlenses 610 belonging to the second group are arranged in a line toward the second direction Dy. Multiple microlenses 610 belonging to the third group are arranged in a line toward the second direction Dy. Multiple microlenses 610 belonging to the first group, multiple microlenses 610 belonging to the second group, and multiple microlenses 610 belonging to the third group are arranged alternately in this order, every three rows toward the first direction Dx. Note that the arrangement layout shown in Figure 10(b) is just an example and can be changed as appropriate.

[0103] According to Modification 5, three types of information can be acquired using three different wavelengths. Therefore, compared to the above embodiment, more information can be acquired in the same measurement time.

[0104] Next, a method for manufacturing the microlens array 600 according to the first embodiment will be described. Figure 11 is a diagram illustrating the method for manufacturing the microlens array 600 by photolithography.

[0105] First, the material for the microlens 610 is applied to the entire surface of the transparent substrate 1100. Here, it is assumed that the material for the microlens 610, which is the first wavelength selector 612, is applied to the entire surface of the transparent substrate 1100. Also, when the microlens array 600 is manufactured by photolithography, the material for the microlens 610 is a photosensitive resin 1102. Next, the entire transparent substrate 1100 is heated (pre-baked). This causes the solvent contained in the material for the microlens 610 to evaporate.

[0106] Next, a photomask with a pattern corresponding to the arrangement layout of the microlenses 610, which are the first wavelength selection section 612, is placed on the transparent substrate 1100. Furthermore, ultraviolet light is irradiated onto the transparent substrate 1100. This exposes the material of the microlenses 610 in areas of the photomask where the pattern 1108 is not formed.

[0107] Next, development is performed. Specifically, the entire transparent substrate 1100 is immersed in a developing solution to dissolve the material of the exposed microlenses 610. As a result, the microlens material in the unexposed areas remains on the transparent substrate 1100. The microlens material remaining on the transparent substrate 1100 is roughly rectangular in cross-sectional view.

[0108] Next, heat treatment is performed. Specifically, the transparent substrate 1100 is heated to a temperature at which the material of the microlens 610 remaining on the transparent substrate 1100 changes to a liquid state. Due to surface tension, the material of the microlens 610 deforms into a flattened spherical shape. Subsequently, by cooling, the microlens 610, which is the first wavelength selector 612, is formed in the shape shown in Figure 6.

[0109] Although not shown in the diagram, the same process is repeated to form the microlens 610, which is the second wavelength selector 614, on the transparent substrate 1100. Finally, the transparent substrate 1100 on which the microlens 610 is formed is bonded to the separately manufactured stack from the first pinhole layer 602 to the second transmission layer 608 to complete the microlens array 600.

[0110] Figure 12 is a diagram illustrating the manufacturing method of a microlens array 600 using inkjet technology.

[0111] First, prepare mold 1200. Mold 1200 has a shape corresponding to the arrangement layout of the microlenses 610, and has recesses at positions corresponding to each microlens 610.

[0112] Next, the material for the microlenses 610 is applied to each recess of the mold 1200 by an inkjet method. For example, multiple microlens 610 materials belonging to the first group and multiple microlens 610 materials belonging to the second group are applied alternately in two rows toward the right in the drawing.

[0113] Next, a transparent base 1202 made of resin is applied to the entire mold 1200. Here, for example, the resin base 1202 is applied to the entire mold 1200 by a slit-coat method.

[0114] Next, the base 1202 is separated from the mold 1200. During separation, the multiple microlenses 610 adhere to the base 1202 and separate from the mold 1200. Finally, the transparent base 1202 with the microlenses 610 attached is bonded to a separately manufactured stack from the first pinhole layer 602 to the second transparent layer 608 to complete the microlens array 600.

[0115] While the above describes methods for manufacturing the microlens array 600 using photolithography and inkjet methods, the present disclosure also describes other manufacturing methods for manufacturing the microlens array 600.

[0116] [Second Embodiment] Next, a second embodiment will be described. Figure 13(a) is an overhead view of the optical sensor 1 according to the second embodiment. Figure 13(b) is a diagram for explaining transmittance. In the figure, "Red" indicates the transmittance of the first wavelength selector 612 of the microlens array 600, "NIR" indicates the transmittance of the second wavelength selector 614 of the microlens array 600, and "high-pass filter" indicates the transmittance of the first transmission layer 604 and the second transmission layer 608 of the microlens array 600. The same configuration as in the first embodiment will not be described.

[0117] Similar to the first embodiment, the plurality of microlenses 610 belonging to the first group constitute the first wavelength selection unit 612, and the plurality of microlenses 610 belonging to the second group constitute the second wavelength selection unit 614. In Figure 13(a), the plurality of microlenses 610 belonging to the first group and the plurality of microlenses 610 belonging to the second group are arranged alternately in rows toward the first direction Dx, but the arrangement layout can be changed as appropriate.

[0118] In the second embodiment, at least one of the first transparent layer 604 and the second transparent layer 608 is a filter that transmits both light in the first wavelength band and light in the second wavelength band, and blocks light in a predetermined wavelength band other than the first and second wavelength bands. Specifically, for example, in the second embodiment, the first transparent layer 604 and the second transparent layer 608 are a high-pass filter 1300 as shown in Figure 13(b), which, for example, blocks light with a wavelength shorter than 640 nm and transmits light with a wavelength longer than 640 nm. That is, the high-pass filter 1300 transmits light that passes through both the first wavelength selection unit 612 and the second wavelength selection unit 614, while blocking light of wavelengths that should be blocked by the first wavelength selection unit 612 and the second wavelength selection unit 614 but have been transmitted for some reason.

[0119] Therefore, in the second embodiment, similar to the first embodiment, only light in the first wavelength band (for example, 640 nm to 680 nm centered at 660 nm) reaches the partial detection region PAA located in the region that overlaps with the first wavelength selection unit 612 in a plan view. Also, only light in the second wavelength band (for example, 830 nm to 870 nm centered at 850 nm) reaches the partial detection region PAA located in the region that overlaps with the second wavelength selection unit 614 in a plan view.

[0120] According to the second embodiment, a high-pass filter 1300 is provided in place of the transmission section that transmits the entire wavelength range of visible light and infrared light in the first embodiment. By blocking light of wavelengths that do not pass through the first wavelength selection section 612 and the second wavelength selection section 614 with the high-pass filter 1300, the optical density can be improved.

[0121] Furthermore, since the first transmission layer 604 and the second transmission layer 608 only need to transmit the wavelength of light transmitted by the first wavelength selection unit 612 and the second wavelength selection unit 614, they are not limited to a high-pass filter 1300, but may also be a band-pass filter or a low-pass filter.

[0122] [Third Embodiment] Next, a third embodiment will be described. Figure 14(a) is an overhead view of the optical sensor 1 according to the third embodiment. Figure 14(b) is a diagram for explaining transmittance. In the figure, "Magenta" indicates the transmittance of the microlens 610 belonging to the first group, "colorless" indicates the transmittance of the microlens 610 belonging to the second group, and "Yellow" indicates the transmittance of the first and second transparent layers 604 and 608. The same configuration as in Embodiment 1 will not be described.

[0123] In the third embodiment, a plurality of microlenses 610 belonging to either the first group or the second group constitute the first wavelength selector 612. Specifically, for example, a plurality of microlenses 610 belonging to the first group constitute the first wavelength selector 612. The plurality of microlenses 610 belonging to the first group transmit only light in the first wavelength band (e.g., 500 nm or less and 700 nm or more). On the other hand, the plurality of microlenses 610 belonging to the second group transmit the entire wavelength range of visible light and infrared light.

[0124] Furthermore, at least one of the first transparent layer 604 and the second transparent layer 608 is a second wavelength selector 614. Specifically, the first transparent layer 604 and the second transparent layer 608 are second wavelength selector 614 that transmit only light in the second wavelength band (for example, 500 nm or more).

[0125] According to the third embodiment, red light is incident on the pixel PX corresponding to the microlens array 600 belonging to the first group. Also, yellow light is incident on the pixel PX corresponding to the microlens array 600 belonging to the second group. As in the third embodiment, even if the multiple microlenses 610 belonging to either the first group or the second group are made transparent, the optical sensor 1 can acquire multiple types of information at multiple wavelengths by making at least one of the first transmission layer 604 and the second transmission layer 608 a second wavelength selection unit 614.

[0126] Within the scope of the spirit of the present invention, a person skilled in the art can conceive of various modifications and alterations, and it is understood that such modifications and alterations also fall within the scope of the present invention. For example, any addition, deletion, or design change of components, or addition, omission, or modification of processes, made by a person skilled in the art to the above-described embodiments, is also included within the scope of the present invention, as long as it retains the gist of the present invention. [Explanation of Symbols]

[0127] 1 Optical sensor, 10 Light receiving unit, 11 Detection control unit, 15 Gate line drive circuit, 16 Signal line selection circuit, 17 Reset circuit, 26 Control circuit, 28 Power supply circuit, 30 Light sensor, 40 Detection unit, 42 Detection signal amplification unit, 43 A / D conversion unit, 44 Signal processing unit, 45 Memory unit, 46 Coordinate extraction unit, 47 Detection timing control unit, 48 Detection circuit, 100 Resin substrate, 110 Barrier inorganic film, 111 First inorganic film, 112 Second inorganic film, 113 Third inorganic film, 120 Addition film, 131 Semiconductor layer, 132 Gate electrode, 133 Source electrode, 134 Drain electrode, 140 Gate insulating film, 150 Interlayer insulating film, 160 Planarization film, 170 Pixel contact unit, 171 Upper electrode contact unit, 180 Inorganic insulating film, 190 Transparent conductive film, 191 192 Transparent conductive film, 293 Transparent conductive film, 310 Lower electrode, 220 Organic material layer, 221 Lower carrier transport layer, 222 Organic light receiving layer, 223 Upper carrier transport layer, 230 Upper electrode, 260 Sealing film, 300 Flexible printed circuit board, 400 Control board, 600 Microlens array, 601 Sensor section, 602 First pinhole layer, 604 First transmission layer, 606 Second pinhole layer, 608 Second transmission layer, 610 Microlens, 612 First wavelength selector section, 614 Second wavelength selector section, 1000 Third wavelength selector section, 1100 Transparent substrate, 1102 Photosensitive resin, 1104 Photosensitive resin after pre-baking, 1106 Exposed photosensitive resin, 1108 Photomask pattern, 1200 Mold, 1202 Base, 1300 high-pass filter, ASW selection signal, BA bending region, Cad additional capacitance, Cb capacitance element, CK clock signal, CL circuit layer, COM reference signal, Cs holding capacitance, CsL1 first holding capacitance line, CsL2 second holding capacitance line, DA detection region, GCL gate line, Lout output signal line, Lrst reset signal line, Lsel selection signal line, Lvr reference signal line, OPL organic photoelectric conversion layer, PA frame region, PAA partial detection region, PAG group region, PX pixel, RST reset signal, RST1 reset signal, RST2 reset signal, RSW reset switch, RW routing wiring, SGL signal line, SSW output switch, STV start signal, T terminal section, TATerminal region, TFT thin-film transistor, Tr first switching element, TrS second switching element, TrR third switching element, VDDSNS sensor power supply signal, Vdet first detection signal, Vgcl gate drive signal, Vo sensor output, Vref reference potential, W1 first wiring layer, W2 second wiring layer.

Claims

1. A light-receiving unit comprising multiple pixels arranged in a matrix on a plane, which receives light from the object to be measured, A first pinhole layer having pinholes at positions overlapping with each of the aforementioned multiple pixels, A first light-transmitting layer is placed on the first pinhole layer, A pinhole is provided at a position overlapping with each of the aforementioned plurality of pixels, and a second pinhole layer is placed on the first transparent layer, A second light-transmitting layer is placed on top of the second pinhole layer, The second transparent layer includes a plurality of microlenses belonging to a first group and a plurality of microlenses belonging to a second group, which are arranged in positions that overlap with the plurality of pixels on the second transparent layer, One of the plurality of microlenses belonging to the first group and the plurality of microlenses belonging to the second group is a first wavelength selector that transmits light in the first wavelength band, At least one of the plurality of microlenses belonging to the first group and the other of the plurality of microlenses belonging to the second group, the first transmission layer, and the second transmission layer is a second wavelength selector that transmits light in the second wavelength band. The first wavelength band is shorter than the second wavelength band. The pinholes in the first pinhole layer provided at positions corresponding to the plurality of microlenses belonging to the first group have a smaller diameter than the pinholes in the first pinhole layer provided at positions corresponding to the plurality of microlenses belonging to the second group. An optical sensor characterized by the following:

2. The plurality of microlenses belonging to the first group constitute the first wavelength selector, The plurality of microlenses belonging to the second group constitute the second wavelength selector, The optical sensor according to claim 1, characterized in that the first group and the second group are arranged in a planar configuration.

3. The plurality of microlenses belonging to the first group constitute the first wavelength selector, The plurality of microlenses belonging to the second group constitute the second wavelength selector, The optical sensor according to claim 1, characterized in that the microlenses belonging to the second group are arranged on each of the four sides of the microlenses belonging to the first group.

4. The plurality of microlenses belonging to the first group constitute the first wavelength selector, The plurality of microlenses belonging to the second group constitute the second wavelength selector, At least one of the first and second transparent layers is a filter that transmits both light in the first wavelength band and light in the second wavelength band, and blocks light in a predetermined wavelength band other than the first and second wavelength bands. The optical sensor according to any one of features 1 to 3.

5. The plurality of microlenses belonging to the first group have a larger diameter than the plurality of microlenses belonging to the second group. The optical sensor according to any one of features 1 to 4.

6. The plurality of microlenses belonging to the first group are shorter in height than the plurality of microlenses belonging to the second group. The optical sensor according to any one of features 1 to 5.

7. Furthermore, it includes a plurality of microlenses belonging to a third group, which are arranged in positions that overlap with the plurality of pixels on the second transmission layer, The plurality of microlenses belonging to the third group are third wavelength selectors that transmit light in the third wavelength band. The optical sensor according to any one of features 1 to 6.

8. The plurality of microlenses belonging to either the first group or the second group constitute the first wavelength selector, At least one of the first and second transmission layers is the second wavelength selection section. The optical sensor according to feature 1.

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