Detection device

Abstract

To provide a detection device capable of suppressing power loss.SOLUTION: A detection device comprises: an optical sensor including a plurality of photodiodes planarly arranged; a light source including a plurality of light-emitting elements for irradiating the plurality of photodiodes with light; and an object to be detected placement section that has a light-transmitting property and is arranged between the optical sensor and the light source, and on which a plurality of objects to be detected are to be placed. The plurality of photodiodes are arranged in a matrix in a first direction and a second direction intersecting the first direction, and are sequentially driven along the second direction at least one row by one row. The plurality of light-emitting elements are arranged in the matrix in the first direction and the second direction, and are sequentially driven along the second direction at least one row by one row. At predetermined time, photodiodes to be driven among the plurality of photodiodes correspond to light-emitting elements to be lit among the plurality of light-emitting elements in plan view.SELECTED DRAWING: Figure 7

Description

[Technical Field]

[0001] The present invention relates to a detection device. [Background technology]

[0002] Patent Document 1 discloses an image acquisition device that includes an optical sensor, a container containing microorganisms and a culture medium, and a light source, and acquires images over time that show the growth of the microorganisms in the container. In Patent Document 1, one point light source is arranged for multiple microorganisms (detectable objects) in the culture container. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-033430 Summary of the Invention [Problem to be solved by the invention]

[0004] In such a detection device, there is a demand for detecting multiple objects to be detected in a detection area with a larger area, which requires multiple light-emitting elements. In this case, the multiple light-emitting elements are continuously lit over the entire surface while the optical sensor (a photosensor in Patent Document 1) is scanning in a predetermined direction. Therefore, the multiple light-emitting elements irradiate light onto areas of the optical sensor that are not being driven, which may result in power loss.

[0005] An object of the present invention is to provide a detection device that can suppress power loss. [Means for solving the problem]

[0006] A detection device according to one embodiment of the present disclosure includes an optical sensor including a plurality of photodiodes arranged in a planar manner, a light source including a plurality of light-emitting elements that irradiate light onto the plurality of photodiodes, and a translucent object to be detected mounting portion arranged between the optical sensor and the light source for mounting a plurality of objects to be detected, wherein the plurality of photodiodes are arranged in a matrix in a first direction and a second direction that intersects the first direction, and are sequentially driven at least one row at a time along the second direction, and the plurality of light-emitting elements are arranged in a matrix in the first direction and the second direction, and are sequentially driven at least one row at a time along the second direction, and at a predetermined time, a photodiode that is driven among the plurality of photodiodes corresponds to a light-emitting element that is lit among the plurality of light-emitting elements in a planar view. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view schematically showing a detection device according to an embodiment. [Figure 2] FIG. 2 is a block diagram illustrating an example of the configuration of the detection device according to the embodiment. [Figure 3] FIG. 3 is a circuit diagram showing an optical sensor of the detection device according to the embodiment. [Figure 4] FIG. 4 is a circuit diagram showing an example of the configuration of a sensor pixel and a detection circuit of the detection device according to the embodiment. [Figure 5] FIG. 5 is a timing waveform diagram showing an example of the operation of the detection device according to the embodiment. [Figure 6] FIG. 6 is a plan view schematically showing an example of the operation of the detection device according to the embodiment. [Figure 7] FIG. 7 is a cross-sectional view schematically illustrating an example of the operation of the detection device according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0008] Modes (embodiments) for carrying out the present disclosure will be described in detail with reference to the drawings. The present disclosure is not limited to the contents described in the following embodiments. Furthermore, the components described below include those that can be easily imagined by a person skilled in the art and those that are substantially identical. Furthermore, the components described below can be combined as appropriate. Note that the disclosure is merely an example, and any appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the present disclosure are naturally included within the scope of the present disclosure. Furthermore, for clarity of explanation, the drawings may schematically depict the width, thickness, shape, etc. of each part compared to the actual embodiment. However, these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this disclosure and each figure, elements similar to those described above with reference to the previous figures may be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0009] In the present disclosure, when expressing an aspect of placing another structure on top of a certain structure, the term "on top" is used, unless otherwise specified, to include both a case in which another structure is placed directly on top of a certain structure so as to be in contact with the certain structure, and a case in which another structure is placed above a certain structure via yet another structure.

[0010] (Embodiment) Fig. 1 is a cross-sectional view schematically illustrating a detection device according to an embodiment. As shown in Fig. 1, the detection device 1 includes an optical sensor 10, an optical filter layer 50, a container 110 for accommodating a detection target 100, and a light source 80. The container 110 (detection target 100) is disposed between the optical sensor 10 and the light source 80. In this embodiment, the detection device 1 is arranged in the following order: optical sensor 10, optical filter layer 50, container 110 (detection target 100), and light source 80. However, the present invention is not limited to this, and the detection device 1 may be arranged in the following order: light source 80, container 110 (detection target 100), optical filter layer 50, and optical sensor 10.

[0011] The detection object 100 is a minute object such as bacteria. When bacteria or the like are cultured on a culture medium 102 and grow into a visible mass, this mass may be referred to as a colony. The detection device 1 is a biosensor that detects minute objects such as bacteria. Note that the detection object 100 is not limited to bacteria, and may be other minute objects such as cells.

[0012] The container 110 includes a container body 111 and a cover member 112. The container 110 is, for example, a petri dish. The container 110 is translucent. A culture medium 102 is accommodated in the container body 111, and the detectable substances 100 are cultured in the culture medium 102. In other words, the container 110 (at least the container body 111 of the container body 111 and the cover member 112) is a translucent detectable substance installation portion for mounting multiple detectable substances 100 thereon.

[0013] In this embodiment, the container 110 is arranged with the container body 111 on the lower side and the cover member 112 on the upper side. This is not limiting, and the container 110 may be arranged upside down. That is, the container 110 may be arranged with the container body 111 on the upper side and the cover member 112 on the lower side. In this case, the detectable substance 100, such as bacteria, is placed on the upper side of the culture medium 102 and cultured, and when imaging the detectable substance 100, the container 110 is arranged upside down so that the detectable substance 100 is arranged below the culture medium 102. The detectable substance 100 and the culture medium 102 to be detected are contained in the container 110 and arranged between the optical sensor 10 and the light source 80.

[0014] The optical sensor 10 is a detection device including a plurality of photodiodes 30 arranged in a plane. Each photodiode 30 is a light detection element that outputs an electrical signal in response to light irradiated thereon. More specifically, the photodiodes 30 are PIN (Positive Intrinsic Negative) photodiodes using inorganic semiconductors or OPD (Organic Photodiodes) using organic semiconductors.

[0015] The optical filter layer 50 is an optical directivity control element disposed between a plurality of light-emitting elements 82 (light source 80) and a plurality of photodiodes 30 (optical sensors 10). More specifically, the optical filter layer 50 is provided between the plurality of photodiodes 30 of the optical sensor 10 and the container 110. The optical filter layer 50 is disposed opposite the plurality of photodiodes 30 of the optical sensor 10. The optical filter layer 50 is an optical element that transmits, toward the photodiodes 30, components of the light emitted from the plurality of light-emitting elements 82 that travel in a direction perpendicular to the optical sensor 10. The optical filter layer 50 is also called a collimating aperture or a collimator.

[0016] The light source 80 includes a light source substrate 81 and a plurality of light-emitting elements 82. The plurality of light-emitting elements 82 are point light sources provided corresponding to the plurality of photodiodes 30 of the optical sensor 10. The plurality of light-emitting elements 82 are provided on the light source substrate 81 and arranged opposite the plurality of photodiodes 30 of the optical sensor 10. Each of the plurality of light-emitting elements 82 is formed, for example, by a light-emitting diode (LED: Light Emitting Diode).

[0017] Light emitted from the light emitting element 82 passes through the cover member 112, the culture medium 102, the container body 111, and the optical filter layer 50, and is irradiated onto the multiple photodiodes 30 of the optical sensor 10. The amount of light irradiated onto the multiple photodiodes 30 differs between the area overlapping with the object to be detected 100 and the area not overlapping with the object to be detected 100. This allows the optical sensor 10 to capture an image of the object to be detected 100.

[0018] Fig. 2 is a block diagram showing an example of the configuration of a detection device according to an embodiment. As shown in Fig. 2, the detection device 1 further includes a control circuit 70 that controls the optical sensor 10 and the light source 80. The control circuit 70 controls the detection operation of the object 100 by the optical sensor 10 in synchronization (or asynchronously) with the lighting operation of the light emitting element 82 by the light source 80. The control circuit 70 is configured with, for example, an MCU (Micro Control Unit), RAM, EEPROM, ROM, etc.

[0019] The optical sensor 10 includes an array substrate 2, a plurality of sensor pixels 3 (photodiodes 30) formed on the array substrate 2, a first gate line driving circuit 15, and a second gate line driving circuit 16.

[0020] The array substrate 2 is formed using a substrate 21 as a base. Each of the sensor pixels 3 includes a photodiode 30, a plurality of transistors, and various wirings. The array substrate 2 on which the photodiodes 30 are formed is a drive circuit substrate that drives the sensors for each predetermined detection area, and is also called a backplane or active matrix substrate.

[0021] The substrate 21 has a detection area AA and a peripheral area GA. A plurality of sensor pixels 3 (a plurality of photodiodes 30) are arranged in a matrix in the detection area AA. That is, the plurality of photodiodes 30 are arranged in a first direction Dx and a second direction Dy intersecting the first direction Dx. Furthermore, a first gate line driving circuit 15 and a second gate line driving circuit 16 are provided in the peripheral area GA.

[0022] In the following description, the first direction Dx is a direction in a plane parallel to the substrate 21. The second direction Dy is a direction in a plane parallel to the substrate 21, and is a direction perpendicular to the first direction Dx. The second direction Dy may intersect the first direction Dx without being perpendicular thereto. The third direction Dz is a direction perpendicular to the first direction Dx and the second direction Dy, and is a normal direction to the main surface of the substrate 21. Furthermore, "plan view" refers to the positional relationship when viewed from a direction perpendicular to the substrate 21.

[0023] The control circuit 70 is a circuit that supplies control signals (such as a clock signal CLK and a start signal ST) to the first gate line drive circuit 15 and the second gate line drive circuit 16, respectively, and controls their operations. Specifically, the first gate line drive circuit 15 outputs a gate drive signal (for example, a reset control signal RST) to a reset control scan line GLrst (see FIG. 3) based on the control signal. The second gate line drive circuit 16 outputs a gate drive signal (for example, a read control signal RD) to a read control scan line GLrd (see FIG. 3) based on the control signal. The control circuit 70 may be provided on a wiring substrate electrically connected to the array substrate 2, or may be provided in the peripheral area GA of the array substrate 2.

[0024] The photodiodes 30 included in the plurality of sensor pixels 3 perform detection in accordance with gate drive signals supplied from the first gate line drive circuit 15 and the second gate line drive circuit 16. The plurality of photodiodes 30 output electrical signals corresponding to the light irradiated thereon as detection voltages Vdet to the detection circuit 11 (see FIG. 3). The detection circuit 11 processes the detection voltages Vdet from the plurality of photodiodes 30 and outputs a sensor value So based on the detection voltages Vdet to the control circuit 70. In this way, the detection device 1 detects information related to the object to be detected 100. The detection circuit 11 may be included in the control circuit 70, or may be provided as a circuit separate from the control circuit 70.

[0025] The light source 80 has a light-emitting element drive circuit 73 that drives a plurality of light-emitting elements 82 mounted on a light source substrate 81. The plurality of light-emitting elements 82 are arranged in a matrix in an area overlapping with the detection area AA of the light source substrate 81. That is, the plurality of light-emitting elements 82 are arranged in a first direction Dx and a second direction Dy that intersects with the first direction Dx. The light-emitting element drive circuit 12 supplies power supply voltages (anode power supply voltage AN, cathode power supply voltage CS) to the plurality of light-emitting elements 82 based on control signals (clock signal CLK, start signal ST, etc.) from the control circuit 70. This causes the plurality of light-emitting elements 82 to be switched on (lighted state) and off (non-lighted state).

[0026] An anode power supply voltage AN is supplied to the anodes of the plurality of light-emitting elements 82 through an anode power line ANL. The anode power line ANL extends in the first direction Dx and is arranged in a plurality of lines in the second direction Dy. That is, the plurality of light-emitting elements 82 arranged in the first direction Dx are connected to a common anode power line ANL.

[0027] A cathode power supply voltage CS is supplied to the cathodes of the plurality of light-emitting elements 82 through a cathode power line CSL. The cathode power line CSL extends in the second direction Dy and is arranged in a plurality of lines in the first direction Dx. That is, the plurality of light-emitting elements 82 arranged in the second direction Dy are connected to a common cathode power line CSL.

[0028] The light-emitting element drive circuit 73 sequentially supplies an anode power supply voltage AN to the multiple anode power lines ANL in a time-division manner based on a control signal from the control circuit 70. The light-emitting element drive circuit 73 also simultaneously supplies a cathode power supply voltage CS to the multiple cathode power lines CSL based on a control signal from the control circuit 70. This causes the multiple light-emitting elements 82 to be driven sequentially at least row by row along the second direction Dy. Details of the method for driving the multiple light-emitting elements 82 will be described later with reference to FIG. 5 and subsequent drawings. The wiring patterns of the anode power supply lines ANL and cathode power supply lines CSL for driving the multiple light-emitting elements 82 are merely examples, and any configuration may be used as long as it can drive the multiple light-emitting elements 82 sequentially at least row by row. For example, the light source substrate 81 of the light source 80 may be configured as an active matrix substrate.

[0029] Furthermore, the number of the plurality of light-emitting elements 82 is smaller than the number of the plurality of photodiodes 30. The arrangement pitch Px2 of the plurality of light-emitting elements 82 in the first direction Dx is larger than the arrangement pitch Px1 of the plurality of photodiodes 30 in the first direction Dx. The arrangement pitch Py2 of the plurality of light-emitting elements 82 in the second direction Dy is larger than the arrangement pitch Py1 of the plurality of photodiodes 30 in the second direction Dy.

[0030] 2, the arrangement pitches Px1, Py1, Px2, and Py2 are the arrangement intervals of one side of the external shapes of the plurality of photodiodes 30 and the plurality of light-emitting elements 82. However, without being limited to this, the arrangement pitches Px1, Py1, Px2, and Py2 may be the intervals between the geometric centers of the plurality of light-emitting elements 82 and the plurality of photodiodes 30.

[0031] Next, a circuit configuration and an example of operation of the optical sensor 10 will be described. Fig. 3 is a circuit diagram showing an optical sensor of a detection device according to an embodiment. As shown in Fig. 3, the sensor pixel 3 has a photodiode 30, a reset transistor Mrst, a readout transistor Mrd, and a source follower transistor Msf. In addition, the sensor pixel 3 is provided with a reset control scanning line GLrst and a readout control scanning line GLrd as detection drive lines (gate lines), and a signal line SL as wiring for signal readout.

[0032] The reset control scanning line GLrst, the readout control scanning line GLrd, and the signal line SL are each connected to a plurality of sensor pixels 3. Specifically, the reset control scanning line GLrst and the readout control scanning line GLrd extend in a first direction Dx and are connected to a plurality of sensor pixels 3 arranged in the first direction Dx. The signal line SL extends in a second direction Dy and is connected to a plurality of sensor pixels 3 arranged in the second direction Dy. The signal line SL is a wiring through which signals from a plurality of transistors (readout transistors Mrd and source follower transistors Msf) are output.

[0033] The reset transistor Mrst, the readout transistor Mrd, and the source follower transistor Msf are provided corresponding to one photodiode 30. Each of the multiple transistors included in the sensor pixel 3 is configured as an n-type TFT (Thin Film Transistor). However, without being limited to this, each transistor may be configured as a p-type TFT.

[0034] A common voltage VCOM is applied to the anode of the photodiode 30. The cathode of the photodiode 30 is connected to a node N1. The node N1 is connected to one of the source or drain of the reset transistor Mrst and the gate of the source follower transistor Msf. When light is irradiated onto the photodiode 30, a signal (charge) output from the photodiode 30 is accumulated in a capacitance element Cs formed at the node N1.

[0035] The gate of the reset transistor Mrst is connected to a reset control scanning line GLrst. A reset voltage VPP1 is supplied to the other of the source or drain of the reset transistor Mrst. When the reset transistor Mrst is turned on (conductive) in response to a reset control signal RST supplied from the first gate line driving circuit 15, the voltage of the node N1 is reset to the reset voltage VPP1. The common voltage VCOM has a voltage lower than the reset voltage VPP1, and the photodiode 30 is reverse-bias driven.

[0036] The source follower transistor Msf is connected between a terminal to which a power supply voltage VPP2 is supplied and the readout transistor Mrd (node ​​N2). The gate of the source follower transistor Msf is connected to the node N1. A signal (voltage) corresponding to the signal (charge) generated in the photodiode 30 is supplied to the gate of the source follower transistor Msf. As a result, the source follower transistor Msf outputs a voltage corresponding to the signal (charge) generated in the photodiode 30 to the readout transistor Mrd.

[0037] The readout transistor Mrd is connected between the source (node ​​N2) of the source follower transistor Msf and the signal line SL. The gate of the readout transistor Mrd is connected to the readout control scanning line GLrd. When the readout transistor Mrd is turned on in response to a readout control signal RD supplied from the second gate line drive circuit 16, a signal (voltage) output from the source follower transistor Msf, i.e., a signal corresponding to the signal (charge) generated in the photodiode 30, is output to the signal line SL as a detection voltage Vdet. Each of the multiple signal lines SL is connected to the detection circuit 11.

[0038] 3, the reset transistor Mrst and the readout transistor Mrd each have a single-gate structure, but the reset transistor Mrst and the readout transistor Mrd may each have a so-called double-gate structure in which two transistors are connected in series, or may each have a structure in which three or more transistors are connected in series. Furthermore, the circuit of one sensor pixel 3 is not limited to a structure having three transistors: the reset transistor Mrst, the source follower transistor Msf, and the readout transistor Mrd. The sensor pixel 3 may have two transistors, or may have four or more transistors.

[0039] 4 is a circuit diagram showing an example of the configuration of a sensor pixel and a detection circuit of a detection device according to an embodiment. For ease of understanding, FIG. 4 shows an example in which one sensor pixel 3 (photodiode 30) is connected to one detection circuit 11.

[0040] 4, the detection circuit 11 includes an amplifier circuit 41, an A / D conversion circuit 42, a first switch element SW_p, a first capacitance element Cp, a second switch element SW_n, and a second capacitance element Cn. The first switch element SW_p and the first capacitance element Cp are connected to a non-inverting input (+) of the amplifier circuit 41. The second switch element SW_n and the second capacitance element Cn are connected to an inverting input (-) of the amplifier circuit 41.

[0041] One end of the first switch element SW_p is electrically connected to the output side of the read transistor Mrd via a signal line SL, and the other end of the first switch element SW_p is connected to the first capacitance element Cp and the non-inverting input (+) of the amplifier circuit 41.

[0042] One end of the second switch element SW_n is electrically connected to the output side of the read transistor Mrd via a signal line SL. The other end of the second switch element SW_n is connected to the second capacitance element Cn and the inverting input (-) of the amplifier circuit 41. The detection circuit 11 switches the connection states of the first switch element SW_p and the second switch element SW_n in synchronization with a control signal from the control circuit 70. As a result, the signal line SL is electrically connected to either the non-inverting input (+) or the inverting input (-) of the amplifier circuit 41.

[0043] During the reset period, the first gate line drive circuit 15 sets the reset control scanning line GLrst to a high-level voltage ("H"), and the second gate line drive circuit 16 sets the readout control scanning line GLrd to "H". This turns on the reset transistor Mrst and the readout transistor Mrd. Also during the reset period, the detection circuit 11 turns off the first switch element SW_p and turns on the second switch element SW_n. As a result, during the reset period, a charge corresponding to the reset voltage VPP1 is charged in the second capacitance element Cn.

[0044] After the reset period, during the exposure period, the photodiode 30 is irradiated with light from the light source 80 (light-emitting element 82). During the readout period after the exposure period, the first gate line drive circuit 15 sets the reset control scanning line GLrst to a low-level voltage ("L"), and the second gate line drive circuit 16 sets the readout control scanning line GLrd to "H." This turns off the reset transistor Mrst and turns on the readout transistor Mrd. Also, during the readout period, the detection circuit 11 turns on the first switch element SW_p and turns off the second switch element SW_n. This causes a charge corresponding to the detection voltage Vdet (the voltage at node N2 after exposure) to be charged in the first capacitance element Cp.

[0045] The amplifier circuit 41 amplifies the potential difference between the reset voltage VPP1 charged in the second capacitance element Cn during the reset period and the detection voltage Vdet charged in the first capacitance element Cp during the read period. The A / D conversion circuit 42 converts the value amplified by the amplifier circuit 41 into a digital signal.

[0046] In this way, in the detection device 1 of this embodiment, a sampling timing is provided for acquiring digital data corresponding to each sensor pixel 3 for each "H" period of the readout control scanning line GLrdn of the nth row (i.e., for each photodiode 30-n of the nth row that is driven).

[0047] A constant current source 43 for supplying a bias current Ib to the readout transistor Mrd is also connected to the detection circuit 11. This makes it possible to detect the detection voltages (the reset voltage VPP1 in the reset period and the detection voltage Vdet in the readout period) of the sensor pixel 3. The constant current source 43 may be provided within the detection circuit 11 or within the substrate 21.

[0048] Next, an operation example of the optical sensor 10 and the light source 80 in the detection device 1 of this embodiment will be described with reference to Fig. 5 to Fig. 7. Fig. 5 is a timing waveform diagram showing an operation example of the detection device according to the embodiment. Fig. 6 is a plan view schematically showing an operation example of the detection device according to the embodiment. Fig. 7 is a cross-sectional view schematically showing an operation example of the detection device according to the embodiment.

[0049] 6 and 7, among the multiple photodiodes 30, the photodiodes 30 that are driven are shown with hatching, and the photodiodes 30 that are not driven are shown without hatching. The photodiodes 30 that are driven are the photodiodes 30 that belong to the sensor pixels 3 whose readout control scanning lines GLrd are "H". The photodiodes 30 that are not driven are the photodiodes 30 that belong to the sensor pixels 3 whose readout control scanning lines GLrd are "L".

[0050] 6 and 7, of the plurality of light-emitting elements 82, the light-emitting elements 82 that are lit are shown hatched, and the light-emitting elements 82 that are not lit are shown without hatching. The light-emitting elements 82 that are lit are light-emitting elements 82 to which the anode power supply voltage AN is supplied from the light-emitting element drive circuit 73, and the light-emitting elements 82 that are not lit are light-emitting elements 82 to which the anode power supply voltage AN is not supplied from the light-emitting element drive circuit 73.

[0051] 5 and 7. FIG. 6 shows the driving of the photodiode 30 and the lighting of the light emitting element 82 corresponding to time t6 in FIGS.

[0052] 5 to 7, the plurality of photodiodes 30 are sequentially driven row by row along the second direction Dy. The plurality of light-emitting elements 82 are sequentially driven every three rows along the second direction Dy. At a given time, the photodiodes 30 that are driven among the plurality of photodiodes 30 and the light-emitting elements 82 that are turned on among the plurality of light-emitting elements 82 correspond to each other in a plan view.

[0053] 5, at time t1, the second gate line drive circuit 16 sets the read control scanning line GLrd1 of the first row to "H" based on the read clock signal ReadCLK. This turns on the read transistor Mrd connected to the read control scanning line GLrd1 of the first row, and drives the photodiode 30-1 of the first row among the multiple photodiodes 30. Note that, among the multiple photodiodes 30, the photodiodes 30 of the other rows except for the driven photodiode 30-1 of the first row are not driven.

[0054] While the readout control scanning line GLrd1 of the first row is at "H", the first gate line driving circuit 15 sets the reset control scanning line GLrst to "H" (not shown in FIG. 5) based on the reset clock signal ResetCLK. This resets the photodiode 30-1 of the first row. After a predetermined period has elapsed, the reset control scanning line GLrst becomes "L" based on the reset clock signal ResetCLK, and the reset period of the photodiode 30-1 of the first row ends.

[0055] After the reset period ends, while the readout control scanning line GLrd for the first row is at "H," the detection circuit 11 turns on the second switch element SW_n. As a result, a charge corresponding to the reset voltage VPP1 is charged into the second capacitance element Cn. After a predetermined period has elapsed since the second switch element SW_n was turned off, the detection circuit 11 turns on the first switch element SW_p. As a result, a charge corresponding to the detection voltage Vdet of the photodiode 30 (the voltage at the node N2 after exposure) is charged into the first capacitance element Cp.

[0056] In this embodiment, the period during which the first switch element SW_p is on is the readout period of the photodiode 30-1 in the first row to be driven. Also, the period from when the second switch element SW_n is turned off until the first switch element SW_p is turned off is the substantial exposure period Tex of the photodiode 30-1 in the first row to be driven. The substantial exposure period Tex is a period that affects the output value of the amplifier even if the light source 80 is turned on before or after this period.

[0057] The first switch element SW_p turns off, and the readout period and exposure period Tex of the photodiode 30-1 in the first row end. After the readout period and exposure period Tex end, the second gate line drive circuit 16 sets the readout control scanning line GLrd1 in the first row to "L" based on the readout clock signal ReadCLK.

[0058] Next, at time t2, the second gate line drive circuit 16 sets the read control scanning line GLrd2 of the second row to "H" based on the read clock signal ReadCLK. This drives the photodiode 30-2 of the second row among the multiple photodiodes 30. Similar to the driving of the photodiode 30-1 of the first row described above, the reset period, exposure period Tex, and readout period of the photodiode 30-2 of the second row are performed while the read control scanning line GLrd2 is "H."

[0059] After time t3, the second gate line driving circuit 16 sequentially sets the read control scanning line GLrdn (n is a natural number) of the nth row to "H" based on the read clock signal ReadCLK. This drives the photodiode 30-n of the nth row among the multiple photodiodes 30. For each photodiode 30-n of the nth row that is driven, the operations of the reset period, exposure period Tex, and read period described above are sequentially performed.

[0060] 5, the detection device 1 of this embodiment is provided with an exposure period Tex for each photodiode 30-n in the nth row that is driven. That is, for each photodiode 30-n in the nth row, a reset period (a period during which the second switch element SW_n is on), an exposure period Tex, and a readout period (a period during which the first switch element SW_p is on) are repeatedly provided. Furthermore, the length of the exposure period Tex for the photodiode 30-n in the nth row is shorter than the period during which the readout control scanning line GLrdn in the nth row is at "H," i.e., the period during which the readout transistor Mrd in the nth row is on.

[0061] As a result, the detection device 1 of this embodiment can suppress variations in the exposure period Tex for each row of the multiple photodiodes 30, compared to, for example, performing a reset operation on all photodiodes 30 in the detection area AA and then scanning the multiple photodiodes 30 to detect one frame (readout period).

[0062] 6 and 7, the light source 80 lights up the light-emitting element 82 among the plurality of light-emitting elements 82 that corresponds to the photodiode 30 to be driven. Here, the "corresponding light-emitting element 82" refers to the light-emitting element 82 among the plurality of light-emitting elements 82 that is in a row that is closest to the photodiode 30 to be driven in the second direction Dy. The corresponding light-emitting element 82 (i.e., the light-emitting element 82 that lights up) may be arranged so as to overlap with the photodiode 30 to be driven (see, for example, times t2, t3, and t6), or may be arranged so as not to overlap with the photodiode 30 to be driven and to be closer than the other light-emitting elements 82 (see, for example, times t1, t4, and t5).

[0063] Furthermore, the light source 80 lights up the light-emitting elements 82 in two rows adjacent to the light-emitting elements 82 corresponding to the driven photodiode 30 in one direction in the second direction Dy and the other direction in the second direction Dy.

[0064] 7, at time t1, the light-emitting element 82-2 in the second row is turned on in response to the driven photodiode 30-1 in the first row. Furthermore, the light source 80 simultaneously turns on the light-emitting element 82-1 in the first row adjacent to the light-emitting element 82-2 in the second row on one side in the second direction Dy, and the light-emitting element 82-3 in the third row adjacent to the light-emitting element 82-2 in the second row on the other side in the second direction Dy. Furthermore, at time t1, the light-emitting elements 82 in other rows other than the light-emitting elements 82-1, 82-2, and 82-3 that are turned on are not turned on.

[0065] At times t2, t3, and t4, the photodiode 30-2 in the second row, the photodiode 30-3 in the third row, and the photodiode 30-4 in the fourth row are sequentially driven. At this time, the light-emitting element 82 corresponding to each of the driven photodiodes 30-2, 30-3, and 30-4 is the light-emitting element 82-2 in the second row. Then, at times t2, t3, and t4, the light-emitting elements 82-1 and 82-3 in the two rows adjacent to the light-emitting element 82-2 in the second direction Dy are also simultaneously lit. That is, at times t2, t3, and t4, as at time t1, the light-emitting elements 82-1, 82-2, and 82-3 are lit, and the light-emitting elements 82 in the other rows are not lit.

[0066] At time t5, the photodiode 30-5 in the fifth row is driven. Corresponding to the driven photodiode 30-5 in the fifth row, the light-emitting element 82-3 in the third row is turned on. Furthermore, the light source 80 simultaneously turns on the light-emitting element 82-2 in the second row adjacent to the light-emitting element 82-3 in the third row on one side in the second direction Dy, and the light-emitting element 82-4 in the fourth row adjacent to the light-emitting element 82-3 in the third row on the other side in the second direction Dy. At time t5, the light-emitting elements 82-2, 82-3, and 82-4 in the three rows are turned on, and the light-emitting elements 82 in the other rows are not turned on.

[0067] In other words, at time t5, the positional relationship between the driven photodiode 30-5 and the plurality of light-emitting elements 82 is different from that between time t1 and time t4. As a result, the three rows of light-emitting elements 82 that are lit are shifted by one row in the second direction Dy. At time t4, the photodiode 30-4 is driven, and the light-emitting element 82-2 in the second row (the light-emitting element 82 in the first row) that is closest to the photodiode 30-4 in the second direction Dy, and the light-emitting element 82-3 in the third row (the light-emitting element 82 in the second row) that is adjacent to the light-emitting element 82-2 on the other side of the second direction Dy, are lit. At the next time t5, when the photodiode 30-5 that is closer to the light-emitting element 82-3 than the photodiode 30-4 is driven, the light-emitting element 82-4 is lit.

[0068] 6 and 7, at time t6, the photodiode 30-6 in the sixth row is driven. Furthermore, in correspondence with the driven photodiode 30-6, the light-emitting element 82-3 in the third row, which is closest to the photodiode 30-6 in the second direction Dy, is turned on. That is, at time t6, the light-emitting element 82 corresponding to the driven photodiode 30-6 is the light-emitting element 82-3 in the third row. Furthermore, the light-emitting elements 82-2 in the second row and the light-emitting element 82-4 in the fourth row, which are adjacent to the light-emitting element 82-3 in the third row in the second direction Dy, are also turned on at the same time. At time t6, the light-emitting elements 82-2, 82-3, and 82-4 in the three rows are turned on, and the light-emitting elements 82 in the other rows are not turned on.

[0069] 5, during the periods when the photodiode 30-7 in the seventh row and the photodiode 30-8 in the eighth row are driven, the light-emitting elements 82-2, 82-3, and 82-4 in three rows are lit, and the light-emitting elements 82 in the other rows are not lit. At time t9, when the photodiode 30-9 in the ninth row is driven, the light source 80 shifts the light-emitting elements 82 that are lit. As a result, the light-emitting elements 82-3, 82-4, and 82-5 in three rows are lit, and the light-emitting elements 82 in the other rows are not lit. In this manner, the multiple photodiodes 30 and the multiple light-emitting elements 82 are driven row by row in sequence.

[0070] As described above, in the detection device 1 of this embodiment, the light-emitting element 82-m in the mth row corresponding to the driven photodiode 30-n in the nth row is turned on. In this embodiment, at least the light-emitting element 82-m is turned on, and the light-emitting elements 82 in other rows other than the light-emitting element 82-m that is turned on are not turned on. In the example shown in FIGS. 5 to 7, the light-emitting element 82-m and the adjacent light-emitting elements 82-(m-1) and 82-(m+1) are turned on, and the light-emitting elements 82 in other rows are not turned on. Therefore, the detection device 1 can reduce power loss of the light source 80 compared to when all the light-emitting elements 82 are turned on.

[0071] Furthermore, the light source 80 also lights up the light emitting elements 82-(m-1) and 82-(m+1) adjacent to the light emitting element 82-m in the mth row (the light emitting element 82 corresponding to the photodiode 30-n in the nth row that is driven). As a result, even if the distance between the photodiode 30-n in the nth row that is driven and the light emitting element 82-m in the mth row that is lit is different, light is irradiated onto the photodiode 30-n in the nth row from the plurality of light emitting elements 82, and variations in the amount of light can be suppressed.

[0072] 7, the distance in the second direction Dy between the photodiode 30-1 in the first row that is driven and the corresponding light-emitting element 82-2 in the second row at time t1 is greater than the distance in the second direction Dy between the photodiode 30-2 in the second row that is driven and the corresponding light-emitting element 82-2 in the second row at time t2. Even in this case, the photodiode 30-1 in the first row that is driven at time t1 is irradiated with light from the photodiode 30-2 in the second row and the photodiode 30-1 in the first row that is adjacent to it. This makes it possible to suppress variation in the amount of light irradiated on the photodiode 30-1 in the first row and the photodiode 30-2 in the second row.

[0073] 5 to 7 are merely examples and can be modified as appropriate. The plurality of photodiodes 30 are not limited to being driven sequentially row by row, but may be driven row by row depending on the required detection accuracy (resolution), the detection period for one frame, etc. Also, an example has been shown in which three rows of the plurality of light-emitting elements 82 are simultaneously lit for one row of photodiodes 30 being driven. However, the present invention is not limited to this, and the plurality of light-emitting elements 82 may be driven at least row by row.

[0074] Although preferred embodiments of the present disclosure have been described above, the present disclosure is not limited to such embodiments. The contents disclosed in the embodiments are merely examples, and various modifications are possible within the scope of the present disclosure. Appropriate modifications made within the scope of the present disclosure naturally fall within the technical scope of the present disclosure. At least one of various omissions, substitutions, and modifications of components can be made within the scope of the gist of each of the above-described embodiments and modifications. [Explanation of symbols]

[0075] 1. Detection device 10. Optical Sensor 11 Detection circuit 15 First gate line driving circuit 16 Second gate line driving circuit 30 Photodiode 41 Amplification circuit 42 A / D conversion circuit 70 Control circuit 80 light source 82 Light-emitting element 100 Object to be detected 102 Culture medium 110 Container GLrd, GLrd1, GLrd2, GLrdn Readout control scan lines GLrst Reset control scan line Mrst Reset Transistor Mrd readout transistor Msf Source Follower Transistor So sensor value

Claims

1. an optical sensor including a plurality of photodiodes arranged in a plane; a light source including a plurality of light emitting elements that irradiate the plurality of photodiodes with light; a light-transmitting detection target mounting portion disposed between the optical sensor and the light source and configured to mount a plurality of detection targets; the plurality of photodiodes are arranged in a matrix in a first direction and a second direction intersecting the first direction, and are sequentially driven at least row by row along the second direction; the plurality of light-emitting elements are arranged in a matrix in the first direction and the second direction, and are sequentially driven at least row by row along the second direction; At a predetermined time, a photodiode to be driven among the plurality of photodiodes and a light-emitting element to be turned on among the plurality of light-emitting elements correspond to each other in a plan view. Detection device.

2. A row of the light emitting elements among the plurality of light emitting elements that is closest in distance in the second direction to the photodiode to be driven is turned on. The detection device according to claim 1 .

3. Furthermore, among the plurality of light-emitting elements, light-emitting elements in two rows adjacent to the light-emitting element corresponding to the driven photodiode in one direction and the other direction in the second direction are turned on. The detection device according to claim 1 .

4. the number of the light-emitting elements is less than the number of the photodiodes, When the light emitting elements in the first and second rows adjacent in the second direction are lit, if the photodiode to be driven comes close to the light emitting element in the second row, the light emitting element in the third row adjacent in the second direction is further lit. The detection device according to claim 1 .

5. The plurality of light-emitting elements are LEDs (Light Emitting Diodes). The detection device according to claim 1 .

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