Detection device

Abstract

To provide a detection device that can detect colonies with higher accuracy. [Solution] The detection device 1 comprises a light source 22, a planar light sensor 10 in which multiple light sensors for detecting light from the light source 22 are arranged two-dimensionally, a detection target placement section in which a dish in which a culture medium is formed is interposed between the light source 22 and the planar light sensor 10, and a control circuit 30 that controls the operation of the light source 22 and the planar light sensor 10 and processes based on the outputs of the multiple light sensors. The planar light sensor 10 outputs data that reflects the intensity of the light emitted from the light source 22 and passed through the dish. The control circuit 30 extracts the contour created by the edge of the dish in the data as a boundary line, and determines whether a colony has formed based on a comparison of multiple data obtained at different timings. In this determination, the outputs of the light sensors reflected outside the boundary line are excluded from each of the data. The boundary line is the smallest circumferential contour included in the data.

Description

Technical Field

[0001] The present disclosure relates to a detection device.

Background Art

[0002] There is known a device that captures an image of a Petri dish in which a medium for culturing a culture target such as bacteria is formed to obtain an image, and detects colonies formed by the culture target on the medium (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the process related to the detection of colonies, measures are taken to maintain a more favorable environment for the culture target and to suppress the spoilage of the medium. As part of such measures, the Petri dish may be placed in an environment that is relatively cooler than the outside air. As a result, dew may form on the Petri dish. The dew formed on the Petri dish may cause a shadow in the image obtained by imaging the Petri dish. The shadow caused by dew in such an image may be difficult to distinguish from the shadow caused by colonies in such an image. Therefore, dew and colonies may be confused, which may reduce the detection accuracy of colonies.

[0005] The present disclosure has been made in view of the above problems, and an object thereof is to provide a detection device capable of detecting colonies with higher accuracy.

Means for Solving the Problems

[0006] A detection device according to one aspect of the present disclosure comprises a light source that emits light, a planar light sensor in which a plurality of light sensors for detecting light from the light source are arranged two-dimensionally, a detection object placement unit provided so as to be able to place the detection object between the light source and the planar light sensor, and a processing unit that controls the operation of the light source and the planar light sensor and processes based on the outputs of the plurality of light sensors, wherein the detection object is a culture medium contained in a container dish, the planar light sensor outputs data that reflects the intensity of light emitted from the light source that has passed through the detection object and reached the plurality of light sensors, the processing unit performs an extraction process that extracts a circumferential contour created in the data by the edge of the dish as a boundary line, and a determination process that determines whether colonies have formed in the culture medium based on a comparison of the plurality of data obtained at different timings, in which the output of the light sensors reflected outside the boundary line is excluded from each of the plurality of data. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 shows the main components of the detection device. [Figure 2] Figure 2 shows an example configuration of the detection area and wiring area. [Figure 3] Figure 3 is a circuit diagram showing the circuit configuration of the light sensor. [Figure 4] Figure 4 is a schematic diagram showing an example configuration of the light source 22. [Figure 5] Figure 5 is a schematic diagram illustrating an example of the detection system configuration. [Figure 6] Figure 6 is a schematic diagram showing the relationship between one detection device and the external configuration. [Figure 7] Figure 7 is a schematic diagram showing the main components of the detection device and the structure of each part, including the object to be detected, which is installed in the detection device. [Figure 8] Figure 8 is a schematic plan view showing the object to be detected, placed on a light-transmitting member, as seen from the side of the planar light sensor. [Figure 9]Figure 9 is a schematic plan view showing an example of colony formation in the culture medium. [Figure 10] Figure 10 is a schematic plan view showing an example of what happens when water droplets form on the object being detected. [Figure 11] Figure 11 is a diagram illustrating the overview of the Hough transform. [Figure 12] Figure 12 shows several examples of circumferences obtained by the Hough transform. [Figure 13] Figure 13 shows an xy coordinate system that distinguishes between the inside and outside of a circle. [Figure 14] Figure 14 is a schematic diagram showing an example of applying mask processing to multiple optical sensors arranged in a detection area. [Figure 15] Figure 15 is a flowchart showing the processing flow related to the operation of the detection device. [Figure 16] Figure 16 is a flowchart showing the initial processing flow. [Figure 17] Figure 17 is a flowchart showing the flow of periodic operations. [Modes for carrying out the invention]

[0008] The embodiments of this disclosure will be described below with reference to the drawings. It should be noted that the disclosure is merely an example, and modifications that can be easily conceived by those skilled in the art while maintaining the spirit of the invention are naturally included within the scope of this disclosure. Furthermore, the drawings may schematically represent the width, thickness, shape, etc., of parts in order to clarify the explanation, but these are merely examples and do not limit the interpretation of this disclosure. In addition, in this specification and the drawings, elements similar to those described above in previously shown drawings are denoted by the same reference numerals, and detailed explanations may be omitted as appropriate.

[0009] Figure 1 shows the main components of the detection device 1. The detection device 1 comprises a planar light sensor 10, a light source panel 20, and a control circuit 30. The planar light sensor 10 and the light source panel 20 of the detection device 1 are connected to the control circuit 30.

[0010] The planar optical sensor 10 has a detection region SA (see FIG. 2) provided on a substrate 11. Further, a reset circuit 13, a scanning circuit 14, and a wiring region VA are mounted on the substrate 11. The configuration on the detection region SA, the reset circuit 13, and the scanning circuit 14 are connected to a detection circuit 15 via the wiring region VA.

[0011] The light source panel 20 has a light emitting region LA that irradiates light to the detection region SA. The light source panel 20 has a light source 22 provided on a substrate 21. The light source 22 emits light. Specifically, the light source 22 has a light emitting element such as, for example, an LED (Light Emitting Diode), and is disposed within the light emitting region LA. In the example shown in FIG. 1, a plurality of light sources 22 are arranged in a matrix on the substrate 21.

[0012] The light source panel 20 is provided with a light source drive circuit 23. The light source drive circuit 23 performs control of the presence or absence of lighting and the luminance during lighting of each of the plurality of light sources 22 under the control of the control circuit 30. The plurality of light sources 22 may be provided so as to be individually light-emitting controllable, or may be provided so as to emit light collectively.

[0013] The control circuit 30 performs various processes related to the operation of the detection device 1. Specifically, the control circuit 30 is a circuit capable of implementing a plurality of functions, such as, for example, an FPGA (Field Programmable Gate Array). The control circuit 30 may be in other forms such as an ASIC (Application Specific Integrated Circuit). The control circuit 30 is connected to the light source drive circuit 23 via a wiring portion 29, and performs processes related to lighting of the light source 22, such as determination of the lighting pattern and lighting timing of the light source 22.

[0014] Furthermore, the control circuit 30 is connected to the detection circuit 15 via the wiring section 19 and receives the output from the detection circuit 15. Here, the control circuit 30 also controls the timing of receiving the output from the detection circuit 15, that is, the timing of operating the scanning circuit 14 to apply a gate signal to the scanning line 6. In this way, the control circuit 30 controls the operation of the light source 22 and the planar light sensor 10. In addition, the control circuit 30 performs processing based on the outputs of multiple light sensors WA. This processing includes various extraction processes such as contour extraction and Hough transform, which will be described later. This processing also includes a determination process to determine whether a colony has been formed. This processing will be described later.

[0015] Although not shown in the figures, the detection device 1 includes an analog-to-digital conversion circuit, a digital-to-analog conversion circuit, and the like. The analog-to-digital conversion circuit is a circuit that enables the output from the optical sensor WA (see Figure 2), transmitted via the detection circuit 15, to be processed by the control circuit 30. The digital-to-analog conversion circuit is a circuit that enables the digital signal generated by the control circuit 30's processing to be used for controlling the operation of the planar optical sensor 10 and the light source panel 20. These circuits may, for example, be partially or entirely included in the detection circuit 15. Alternatively, these circuits may function as circuits mounted on flexible printed circuit boards (FPCs) provided as wiring sections 19 and 29. Furthermore, these circuits may be implemented in the detection device 1 by other means.

[0016] Figure 2 shows an example configuration of the detection region SA and the wiring region VA. Multiple optical sensors WA (see Figure 3) are arranged two-dimensionally in the detection region SA of the planar optical sensor 10. In this embodiment, as shown in Figure 2, multiple optical sensors WA are arranged in a matrix along the first direction Dx and the second direction Dy. The first direction Dx and the second direction Dy are orthogonal. Furthermore, when the third direction Dz is mentioned in the following description, it refers to the direction orthogonal to the first direction Dx and the second direction Dy.

[0017] The reset circuit 13 is connected to the reset signal transmission lines 51, 52, ..., 5n. Hereafter, when reset signal transmission line 5 is mentioned, it refers to any of the reset signal transmission lines 51, 52, ..., 5n. The reset signal transmission line 5 is a wiring along the first direction Dx. In the example shown in Figure 2, n reset signal transmission lines 5 are arranged in the second direction Dy. n is a natural number greater than or equal to 2. These n reset signal transmission lines 5 are connected to the reset circuit 13 at one end of the first direction Dx.

[0018] The scanning circuit 14 is connected to scan lines 61, 62, ..., 6n. Hereafter, when scan line 6 is mentioned, it refers to any of scan lines 61, 62, ..., 6n. Scan line 6 is a wiring along the first direction Dx. In the example shown in Figure 2, n scan lines 6 are aligned in the second direction Dy. These n scan lines 6 are connected to the scanning circuit 14 at the other end of the first direction Dx.

[0019] As shown in Figure 2, the reset signal transmission line 5 and the scan line 6 are arranged alternately in the second direction Dy within the detection region SA. Although the reset circuit 13 and scan circuit 14 exemplified in Figures 1 and 2 are positioned opposite each other across the detection region SA, the layout of the reset circuit 13 and scan circuit 14 is not limited to this and can be changed as appropriate.

[0020] Furthermore, signal lines 71, 72, ..., 7m are provided within the detection area SA. Hereafter, when signal line 7 is mentioned, it refers to one of signal lines 71, 72, ..., 7m. Signal line 7 is routed along the second direction Dy.

[0021] In the example shown in Figure 2, m signal lines 7 are arranged in the first direction Dx, where m is a natural number greater than or equal to 2. Each of these m signal lines 7 is connected at one end in the second direction Dy to one of the multiple switches (for example, switch SW1, switch SW2, switch SW3, or switch SW4) of the multiplexer 40.

[0022] The multiplexer 40 is installed within the wiring area VA. The multiplexer 40 has multiple switches. In the example shown in Figure 2, these multiple switches are shown as switches SW1, SW2, SW3, and SW4. The multiple switches of one multiplexer 40 each turn ON (conductive) at different timings. While one of the multiple switches of one multiplexer 40 is ON (conductive), the other switches are OFF (non-conductive). The number of multiplexers 40 depends on the number (m) of signal lines 7. If the number of switches is p, then the number of multiplexers 40 should be m / p. If there are multiple multiplexers 40, each of the multiple multiplexers 40 is connected to the detection circuit 15 via individual wiring 401, 402, ..., 40p.

[0023] Note that the connection of the signal line 7 to the detection circuit 15 via the multiplexer 40 is merely an example and is not limited to this; the signal line 7 may also be individually directly connected to the detection circuit 15 within the wiring area VA. Within the wiring area VA, the reset circuit 13 is connected to the detection circuit 15 via wiring 131. Within the wiring area VA, the scanning circuit 14 is connected to the detection circuit 15 via wiring 149.

[0024] The detection circuit 15 is involved in detecting light using the PD82 (see Figure 3) provided on the optical sensor WA, and outputs signals to control the operating timing of the reset circuit 13 and the scanning circuit 14 under the control of the control circuit 30. The detection circuit 15 also receives the output from the optical sensor WA as input. The detection circuit 15 converts the signal input from the optical sensor WA into data that can be interpreted by the control circuit 30 and outputs it to the control circuit 30. In this embodiment, the detection circuit 15 is an MCU (Micro Controller Unit).

[0025] Figure 3 is a circuit diagram showing the circuit configuration of the optical sensor WA. Note that the first direction Dx and the second direction Dy in Figure 3 merely correspond to the directions of the reset signal transmission line 5, scan line 6, and signal line 7, and do not strictly represent the relative positional relationship of the circuit configuration within the optical sensor WA.

[0026] As shown in Figure 3, the optical sensor WA is equipped with switching element 81, PD82, transistor element 83, and switching element 85. PD82 is a photodiode (PD). Switching elements 81, 85 and the transistor element are MOSFETs (Metal Oxide Semiconductor Field Effect Transistors).

[0027] The gate of the switching element 81 is connected to the reset signal transmission line 5. A reset potential VReset is applied to either the source or drain of the switching element 81. The cathode of PD82 and the gate of transistor element 83 are connected to the other source or drain of the switching element 81. Hereinafter, when the connection part CP is mentioned, it refers to the other part, the location where the cathode of PD82 and the gate of transistor element 83 are connected. A reference potential VCOM is also applied from the anode side of PD82. The potential difference between the reset potential VReset and the reference potential VCOM is predetermined, but the potentials of the reset potential VReset and the reference potential VCOM may be variable. Note that the reset potential VReset is at a higher potential than the reference potential VCOM.

[0028] The drain of transistor element 83, which functions as a source follower, is supplied with the output source potential VPP2. The source of transistor element 83 is connected to either the source or the drain of switching element 85. The other source or drain of switching element 85 is connected to signal line 7. The gate of switching element 85 is connected to scan line 6.

[0029] The reset potential VReset, the reference potential VCOM, and the output source potential VPP2 are supplied by the detection circuit 15 to the optical sensor WA based on power supplied, for example, via a power supply circuit (not shown) connected to the detection circuit 15. The output form of these potentials is not limited to this and can be changed as appropriate.

[0030] The output source potential VPP2 is predetermined. Furthermore, the source potential of transistor element 83 is lower than the output potential of PD82 by the gate-source voltage (Vth) of transistor element 83. In this case, the source potential of transistor element 83 depends on the reset potential VReset and the reference potential VCOM. The output potential of PD82 depends on the photovoltaic power generated by PD82 in response to the light detected by PD82 during the exposure period.

[0031] When the gate of the switching element 85 is turned ON by the gate signal provided from the scanning circuit 14 via the scanning line 6, the source-drain of the switching element 85 becomes conductive. As a result, the signal (potential) transmitted to the switching element 85 via the transistor element 83 is transmitted to the signal line 7 through the switching element 85. In this way, an output is generated from the optical sensor WA. Hereafter, when referred to as the gate signal, it refers to the signal (potential) provided from the scanning circuit 14 via the scanning line 6. The scanning circuit 14 is a circuit that outputs the gate signal. As explained with reference to Figures 2 and 3, multiple optical sensors WA connected to the scanning line 6 and the signal line 7 are arranged in a matrix in the detection area SA of the planar optical sensor 10. Here, the scanning line 6 is provided along the first direction Dx and is configured to transmit the gate signal that generates an output from the optical sensor WA. The signal line 7 is configured to transmit the output of the optical sensor WA along the second direction Dy.

[0032] The output of one PD82 provided on a single light sensor WA corresponds to the intensity of light detected by the PD82 within a predetermined exposure period. The output of the PD82 is reset in response to a signal provided by the reset circuit 13 via the reset signal transmission line 5. When the gate of the switching element 81 is turned ON by this signal, the source-drain connection of the switching element 81 becomes conductive. This resets the potential of the connection CP to the reset potential VReset.

[0033] Figure 4 is a schematic diagram showing an example configuration of the light source 22. As shown in Figure 4, the light source 22 has a first light source 22R, a second light source 22G, and a third light source 22B. The first light source 22R, the second light source 22G, and the third light source 22B each emit light of a different color. In this embodiment, the first light source 22R emits red (R) light. The second light source 22G emits green (G) light. The third light source 22B emits blue (B) light.

[0034] As shown in "Example 1" of Figure 4, the light source 22 has, for example, a light-emitting region 2201 and a frame region 2202. In the light-emitting region 2201, a first light source 22R, a second light source 22G, and a third light source 22B, which are square in shape from a planar viewpoint, are arranged along the second direction Dy. The frame region 2202 is a frame-shaped region that borders the light-emitting region 2201. The width D1 of the light-emitting region 2201 in the first direction Dx is smaller than the width D2 of the frame region 2202 in the first direction Dx. The height H1 of the light-emitting region 2201 in the second direction Dy is smaller than the height H2 of the frame region 2202 in the second direction Dx. The spacing H3, which is the distance between the first light source 22R and the second light source 22G, and the distance between the second light source 22G and the third light source 22B, is less than half of the height H1. In the "First Example" of Figure 4, the width D1 and height H1 are equal, and the width D2 and height H2 are equal, but at least one of these may be different. Furthermore, the light source 22 may be replaced with a different form, such as the light source 22A shown in the "Second Example" of Figure 4. In light source 22A, the longitudinal directions of the first light source 22R, the second light source 22G, and the third light source 22B are aligned with the second direction Dy, and they are arranged in the order of first light source 22R, second light source 22G, and third light source 22B from one side to the other in the first direction Dx. The first and second examples of Figure 4 are examples of the forms of light sources according to this disclosure and are not limited thereto. The shapes of the first light source 22R, the second light source 22G, and the third light source 22B in a planar view and the positional relationship of the first light source 22R, the second light source 22G, and the third light source 22B can be changed as appropriate. A planar viewpoint is a viewpoint that directly views the plane (Dx-Dy plane) along which the first direction Dx and the second direction Dy lie.

[0035] Figure 5 is a schematic diagram illustrating an example configuration of a detection system 100, which includes a detection device 1. As shown in Figure 5, the detection system 100 comprises a plurality of detection devices 1, a host IC 70, and a connection circuit 125. The plurality of detection devices 1 are electrically connected to a common host IC 70 via the connection circuit 125.

[0036] The incubator 120 shown in Figure 5 is maintained in an environment (temperature, humidity, etc.) suitable for culturing the substance to be detected 200 with its door closed. Multiple detection devices 1 are placed inside the incubator 120.

[0037] Figure 6 is a schematic diagram showing the relationship between one detection device 1 and the external configuration. As shown in Figure 6, the connection between the detection device 1 and the connection circuit 125 is made by the connection between the control circuit 30 and the connection circuit 125. Also, as shown in Figure 6 and Figure 7 described later, the planar light sensor 10 and the light source panel 20 face each other. Furthermore, the object to be detected 200 can be placed between the planar light sensor 10 and the light source panel 20.

[0038] Note that Figure 6 only provides a general overview of the relationship between the planar light sensor 10, the light source panel 20, and the object to be detected 200. The specific structure for installing the object to be detected 200 between the planar light sensor 10 and the light source panel 20 will be explained with reference to Figure 7.

[0039] Figure 7 is a schematic diagram showing the main components of the detection device 1 and the structure of each part, including the object to be detected 200, which is installed in the detection device 1. The object to be detected 200 is a culture medium 215 contained in a container dish 210. The container further has a lid 220. Specifically, the dish 210 is a Petri dish. The lid 220 is the lid of the dish 210. As shown in Figure 8 and other figures described later, the inner diameter of the annular side wall of the lid 220 is greater than or equal to the outer diameter of the annular side wall of the dish 210. That is, the lid 220 has a cylindrical outer wall that covers the cylindrical outer wall of the dish 210 from the outside. The culture medium 215 is a culture medium in which colonies can be cultured. Hereinafter, when simply referred to as a colony, it refers to a colony formed on the object to be detected 200 and cultured in the culture medium 215. The object to be cultured is an object such as biological tissue or microorganism that is expected to be cultured in the culture medium 215. The culture medium 215 exhibits light transmission to such an extent that the degree of light transmission changes depending on the presence or absence of colonies and the thickness of the colonies. The object to be detected 200 is placed on the light-transmitting member 91. The light-transmitting member 91 is a plate-shaped member made of colorless glass or a colorless synthetic resin that has light transmission properties.

[0040] Figure 8 is a schematic plan view showing the object to be detected 200 placed on the light-transmitting member 91 as seen from the planar light sensor 10 side. As shown in Figure 8, the light-transmitting member 91 is a circular member with a diameter that can accommodate the object to be detected 200 inside from a planar viewpoint. The light-transmitting member 91 forms a light-transmitting region between the planar light sensor 10 and the light source panel 20 that can accommodate the object to be detected 200 inside. The light-transmitting member 91 is in contact with the light-shielding member 92 at its outer edge. The light-shielding member 92 is a plate-shaped member into which the light-transmitting member 91 is fitted. The light-shielding member 92 exhibits light-shielding properties.

[0041] The edge 95 shown in Figure 8 is the outer edge of the light-transmitting member 91 and the inner edge of the light-shielding member 92 into which the light-transmitting member 91 is fitted. The edge 95 is a circle from a planar viewpoint. Alternatively, a light-transmitting region within the edge 95 may be formed when the light-transmitting member, which functions as the light-transmitting member 91, overlaps with the light-shielding member 92, which has been cut out in a circular shape to form the inner edge corresponding to the edge 95. In this case, the light-transmitting member 91 does not need to be disc-shaped.

[0042] In this embodiment, a diffuser plate 25 is provided on the light source panel 20 side of the light-transmitting member 91. The diffuser plate 25 is an optical member that diffuses light. The diffuser plate 25 is positioned between the light-transmitting member 91 and the light-emitting region LA of the light source panel 20. When the diffuser plate 25 receives light emitted from the light-emitting region LA from the light source panel 20 side, it transmits the light to the light-transmitting member 91 side, thereby further diffusing the direction of light propagation. This makes the light from the light-emitting region LA, formed by a collection of multiple light sources 22 arranged in two dimensions, more uniform from a planar viewpoint.

[0043] As shown in Figure 7, in this embodiment, an elastic member 93 is provided between the light-shielding member 92 and the light source panel 20. The elastic member 93 is an elastic member that biases the light-shielding member 92 toward the planar light sensor 10. Specifically, the elastic member 93 is, for example, a cylindrical compression coil spring as shown in Figure 7. The object to be detected 200, placed on the light-transmitting member 91, is pressed against a member 26 provided between the planar light sensor 10 and the light-transmitting member 91 by the biasing force that the elastic member 93 exerts on the light-shielding member 92. In this embodiment, the object to be detected mounting section 99 is composed of the light-transmitting member 91, the light-shielding member 92, and the elastic member 93. In other words, the object to be detected mounting section 99 has a light-transmitting member 91 on which the object to be detected is placed, and a light-shielding member 92 that supports the light-transmitting member from its outer circumference, and the boundary between the light-transmitting member 91 and the light-shielding member 92 forms a circle, as shown by the edge 95 in Figure 9. Here, the diameter of the circle traced by the edge 95, that is, the boundary between the light-transmitting member 91 and the light-shielding member 92, is larger than the diameter of the circle traced by the edge of the dish 210.

[0044] Component 26 functions as an optical component that limits the light emitted from the light-emitting region LA of the light source panel 20 to the planar light sensor 10. Specifically, component 26 has one of the following: a plate-shaped louver, a cylindrical aperture, or a microlens. A plate-shaped louver is a plurality of parallel plate-shaped structures whose plate surfaces are aligned along the third direction Dz. It is desirable that the structure be made of a material with strong light-absorbing properties. A cylindrical aperture is a cylindrical opening that penetrates the base of component 26 along a plane perpendicular to the third direction Dz (Dx-Dy plane) in the third direction Dz. It is desirable that the base be made of a material with strong light-absorbing properties. A microlens is a tiny lens whose optical axis is aligned along the third direction Dz. It is desirable that the base of component 26 supporting the microlens be made of a material with strong light-absorbing properties. Regardless of the form of the component 26, as an optical component, the component 26 is provided with the purpose of limiting the direction of propagation of light emitted from the light source 22 and reaching the planar light sensor 10 to the third direction Dz or a direction with a shallower inclination angle with respect to the third direction Dz.

[0045] The third direction Dz of the light-emitting region LA of the light source panel 20 and the detection region SA of the planar light sensor 10 are opposed to each other, and this is maintained by the housing 90. The housing 90 is a light-shielding housing provided to pre-house the light source panel 20, elastic member 93, diffuser plate 25, light-transmitting member 91, light-shielding member 92, member 26, and planar light sensor 10 inside. The positional relationship of each component shown in Figure 7 is established when the object to be detected 200 is placed between member 26 and light-transmitting member 91. In this embodiment, the object to be detected 200 is placed on the light-transmitting member 91 such that the lid 220 side of the object to be detected 200 abuts against the light-transmitting member 91. That is, the object to be detected 200 is placed between the planar light sensor 10 and the light source panel 20 such that the lid 220 is positioned relatively lower and the dish 210 is positioned relatively higher.

[0046] As described above with reference to Figure 7, the detection device 1 of the embodiment has a structure that allows the object to be detected 200 to be placed between the planar light sensor 10 and the light source panel 20. In the placed object to be detected 200, the bottom surface of the dish 210 on which the culture medium 215 is formed is aligned with the detection area SA of the planar light sensor 10 and the light emission area LA of the light source panel 20.

[0047] Light emitted from the light-emitting region LA of the light source panel 20 is diffused by the diffuser plate 25, passes through the light-transmitting member 91, the object to be detected 200, and member 26, and reaches the detection region SA of the planar light sensor 10. Thus, the planar light sensor 10 is configured to output data that reflects the intensity of light emitted from the light source 22, passing through the object to be detected 200, and reaching multiple light sensors WA. The data referred to here is based on the collection of outputs from multiple light sensors WA, and is, for example, an image as described later. The intensity of light reaching the detection region SA is affected by the degree of light transmission by the culture medium 215.

[0048] Figure 9 is a schematic plan view showing an example of the case where colonies 222 are formed in the culture medium 215. As shown in Figure 9, when colonies 222 are formed in the culture medium 215, the degree of light transmission differs between the parts of the culture medium 215 where colonies 222 are not present and the parts where colonies 222 are present. In other words, the formation of colonies 222 causes a change in the degree of light transmission through the culture medium 215. The formation of colonies 222 is detected based on the difference in the degree of light transmission before and after this change. That is, the difference in the degree of light transmission before and after this change is reflected in the light detection result by the detection area SA, thereby detecting the colonies 222 formed in the culture medium 215. Generally, the light transmittance tends to be lower in the area where colonies 222 are present compared to the area where colonies 222 are not present in the culture medium 215, but this description does not rule out the possibility that the opposite may occur.

[0049] Incidentally, condensation may occur on the object being detected 200. Water droplets formed by such condensation (for example, water droplets 240 shown in Figure 10) may affect the light passing between the planar light sensor 10 and the light source panel 20.

[0050] Figure 10 is a schematic plan view showing an example of a case where water droplets 240 form on the object to be detected 200. In this embodiment, the object to be detected 200 is placed inside the incubator 120 shown in Figure 5, and its image is acquired by the detection device 1. Condensation may form on the object to be detected 200 while the image is being acquired. Such water droplets resulting from condensation often form between the annular outer wall of the dish 210 and the inner wall of the lid 220 in a plan view, for example, as shown in the water droplet 240 in Figure 10. In other words, condensation like the water droplet 240 is more likely to occur on the outside of the dish 210.

[0051] If a change in the degree of light transmission (the difference in the degree of light transmission before and after the change) is detected, including the area where the water droplet 240 is formed, the water droplet 240 may be mistakenly considered to be the same as colony 222. In other words, even though no colony like colony 222 has actually formed, the formation of water droplet 240 may lead to the misconception that a colony has formed.

[0052] Therefore, in this embodiment, a mechanism is provided to limit the detection of light by the planar light sensor 10 to the inside of the dish 210. This suppresses the effect of water droplets 240 on the results of light detection by the planar light sensor 10. In other words, it is possible to detect the formation of colonies such as colony 222 with higher accuracy. The mechanism for limiting the detection of light by the planar light sensor 10 to the inside of the dish 210 will be described below. Hereinafter, when simply referred to as a colony, it refers to a colony formed by a cultured subject cultured in the culture medium 215, such as colony 222.

[0053] In order to limit the detection of light by the planar light sensor 10 to the inside of the dish 210, a process is performed to extract the boundaries of the dish 210, lid 220, and light-transmitting member 91, as described with reference to Figure 8. Specifically, the edges of the dish 210, lid 220, and light-transmitting member 91 are extracted as the contour of the training area using a Hough transform.

[0054] Figure 11 is a diagram illustrating the overview of the Hough transform. In the explanation referring to Figure 11, we assume a case where we want to extract a circle 150 with diameter r centered at point 151 in a two-dimensional space of the xy-plane with point 140 as the origin. Furthermore, we assume that points 152, 153, and 154 are points located on the circumference of circle 150.

[0055] For example, the circle whose circumference coincides with point 152 is not limited to circle 150, but there are infinitely many such circles, including circles 161, 162, and 163. Therefore, if we try to find a circle whose circumference coincides with point 152, infinitely many circles will be included in the search. Here, the circumferences of circles 150, 161, and 162 coincide with point 153, but the circumference of circle 163 does not coincide with point 153. Therefore, by limiting the condition for the circle to "the circumference coincides with points 152 and 153," we can exclude circles like circle 163, whose circumference does not coincide with point 153. Furthermore, the circumference of circle 150 coincides with point 154, but the circumferences of circles 161 and 162 do not coincide with point 154. Therefore, by limiting the condition for the circle to "the circumference coincides with points 152, 153, and 154," we can limit the circle to circle 150. In other words, circle 150 is extracted by the Hough transform with a higher priority than other circles such as circles 161, 162, and 163, as it is a "more likely circle" that passes through multiple points (e.g., points 152, 153, and 154) on the circumference of the circle being sought.

[0056] The Hough transform used in this embodiment is used to extract a circle whose circumference overlaps with multiple points, as explained with reference to Figure 11. Specifically, the Hough transform extracts a circle represented by three values ​​(a, b, r). Of these, a and b represent the x-coordinate a and y-coordinate b, which can be expressed as (x, y) = (a, b) in an x, y coordinate system with respect to the origin (for example, point 140). In Figure 11, the coordinates represented by (x, y) = (a, b) are the coordinates of point 151. Also, r represents the diameter r of the circle with the coordinates represented by (x, y) = (a, b) as the center. Any point (x, y) = (X, Y) on the circumference extracted by the Hough transform can be expressed by the following equation (1). r 2 =(Xa) 2 +(Yb) 2 ...(1)

[0057] The extraction of multiple points that overlap the circumference of a circle extracted by the Hough transform, such as points 152, 153, and 154 in Figure 11, is performed using image processing such as contour extraction. Specifically, the set of outputs of multiple optical sensors WA is considered as an image. Here, an image is defined as a set of pixels, where the output of one optical sensor WA is considered as one pixel, and multiple pixels are arranged to correspond to the arrangement of optical sensors WA in the detection region SA. Hereafter, unless otherwise specified, when simply referred to as an image, it refers to the set of outputs of multiple optical sensors WA. Also, unless otherwise specified, when simply referred to as a pixel, it refers to the output of an optical sensor WA. In practice, processing such as analog / digital conversion is performed to treat the output of the optical sensor WA as a pixel. In this embodiment, such processing is performed by the detection circuit 15 as described above, but it may also be performed by the control circuit 30.

[0058] In this embodiment, a contour extraction process is performed on the image to extract multiple contours. These multiple contours include a contour showing the annular outer wall of the dish 210, a contour showing the annular outer wall of the lid 220, and a contour showing the edge 95. Each of these contours is composed of multiple points arranged in an annular pattern. If three or more of these multiple points are arranged in a manner corresponding to a diameter r centered on point 151, such as points 152, 153, and 154 in Figure 11, then a single circle, such as circle 150, can be extracted using the Hough transform. After the contour extraction process, the Hough transform is applied to obtain a, b, and r individually for each of the multiple contours, and the circumference of the circle represented by the three values ​​a, b, and r is extracted.

[0059] In this embodiment, a1, b1, and r1, which represent the circumferences corresponding to the outer wall of the dish 210, a2, b2, and r2, which represent the circumferences corresponding to the outer wall of the lid 220, and a3, b3, and r3, which represent the circumferences corresponding to the edge 95, are determined individually. a1, a2, and a3 each represent the value of a. b1, b2, and b3 each represent the value of b. r1, r2, and r3 each represent the value of r.

[0060] In most cases, the number of points constituting a contour that can be considered a single circle is significantly greater than three. Furthermore, the contour extraction process is a binarization image processing method such as applying a Gaussian filter, but is not limited to this; other image processing methods capable of extracting contours from an image may also be used. In addition, further image processing, such as applying a noise filter, may be performed between the contour extraction process and the Hough transform to obtain contours with higher accuracy.

[0061] In this embodiment, various extraction processes such as contour extraction, Hough transform, and additional image processing are performed by the control circuit 30, but the invention is not limited to this. For example, a separate configuration dedicated to various extraction processes may be provided.

[0062] Figure 12 shows examples of multiple circumferences obtained by the Hough transform. Figure 12 shows three circles, 211, 231, and 950, obtained in an xy coordinate system with point 140 as the origin. Circle 211 can be represented by a1, b1, r1, which represents the circumference corresponding to the outer wall of dish 210. Circle 231 can be represented by a2, b2, r2, which represents the circumference corresponding to the outer wall of lid 220. Circle 950 can be represented by a3, b3, r3, which represents the circumference corresponding to the edge 95.

[0063] Note that point 141 in Figure 12 and Figure 13 (described later) is the coordinate (x,y)=(h,v), where h is the maximum value of the x-coordinate and v is the maximum value of the y-coordinate in the xy coordinate system with point 140 as the origin. One of points 140 and 141 corresponds to one of the two optical sensors WA located at diagonal vertices in the rectangular detection region SA. The other of points 140 and 141 corresponds to the other of the two optical sensors WA located at diagonal vertices in the rectangular detection region SA. Therefore, the xy coordinate system shown in Figures 12 and 13 represents the arrangement of each of the multiple pixels contained in the image by a combination of x-coordinate values ​​and y-coordinate values. In other words, the output of each of the multiple optical sensors WA can be distinguished by a combination of x-coordinate values ​​and y-coordinate values. To put it another way, the rectangular region in Figures 12 and 13 where points 140 and 141 are located diagonally is the region corresponding to the detection region SA in which the multiple optical sensors WA are located.

[0064] As shown in Figure 12, in the extraction process including the Hough transform described above, the outer periphery wall of the dish 210 is extracted as a circle 211 showing a circumferential contour. In addition, in the same extraction process, the outer periphery wall of the lid 220 is extracted as a circle 231 showing a circumferential contour. Furthermore, in the extraction process, a circle 950 corresponding to the edge 95 is extracted. In this embodiment, the inside of the one circumference that is relatively small among the multiple circumferences obtained by the Hough transform is considered to be the inside of the dish 210. Referring to Figure 12, the inside of circle 211 is considered to be the inside of the dish 210.

[0065] Figure 13 shows an xy coordinate system that distinguishes between the inside and outside of circle 211. In Figure 13, within the rectangular region where points 140 and 141 are located diagonally, a portion is shown as the inside of the circle 300, and the other portion is shown as the outside of the circle 310. Inside the circle 300 is inside circle 211. Outside the circle 310 is outside circle 211.

[0066] In this embodiment, masking is performed. Masking, in this context, is a process that prevents the use or generation of output from optical sensors WA located outside the circle 310, among the outputs from multiple optical sensors WA located in the detection region SA. Through masking, the circle 211 is used as a boundary line, and the outputs of the optical sensors WA reflected outside this boundary line are excluded from each image. Here, as explained with reference to Figure 12, the smallest of one or more circumferential contours (circles 211, 231, and 950) included in the image is used as the boundary line.

[0067] In other words, in this embodiment, the masking process limits the output used for colony detection to the output from the optical sensor WA, which is arranged to correspond to the interior 300 of the circle. This limitation restricts the detection of light by the planar optical sensor 10 to light that has passed through the inside of the dish 210. The details of the masking process in this embodiment will be described below with reference to Figure 14.

[0068] Figure 14 is a schematic diagram showing an example of applying mask processing to multiple optical sensors WA arranged in a detection region SA. Each of the multiple rectangles arranged in a matrix by grid lines within the detection region SA shown in Figure 14 schematically represents an optical sensor WA. Optical sensors 441, 442, 443, and 444 in Figure 14 specifically represent four optical sensors WA located at the four corners of the detection region SA. Of these, optical sensor 441 is an optical sensor WA corresponding to the coordinates of point 140 shown in Figures 12 and 13. Optical sensor 444 is an optical sensor WA corresponding to the coordinates of point 141 shown in Figures 12 and 13. Furthermore, the circle 212 shown in Figure 14 is a conceptual projection of the circumference corresponding to circle 211 onto the detection region SA. In Figure 14, the inside and outside of circle 212 are distinguished as the inside 301 and the outside 311. The inside 301 represents the optical sensors WA located inside circle 212 among the multiple optical sensors WA arranged in the detection region SA. The outer circle 311 indicates an optical sensor WA located outside the circle 212, among the multiple optical sensors WA arranged in the detection region SA.

[0069] The area inside the circle 301 is considered to be the inside of the dish 210. Therefore, the degree of light detection indicated by the output of the area inside the circle 301 is used to detect the occurrence of a colony. Specifically, if a dark area that was not present in the earlier of two images taken in different time periods appears in the later of the two images, then that dark area is considered to be due to the occurrence of a colony. The earlier of the two images taken in different time periods is, for example, the first, second, and third data obtained in the initial operation described later. The later of the two images taken in different time periods is, for example, the first, second, and third data obtained in the periodic operation described later. Both of the two images taken in different time periods are images that reflect the output of the area inside the circle 301.

[0070] The outer circle 311 is considered to be outside the dish 210. Therefore, the degree of light detection indicated by the output of the outer circle 311 is not used to detect the occurrence of a colony. In this embodiment, in a row of optical sensors WAs aligned along the first direction Dx where all optical sensors WAs are located outside the circle 311, the optical sensors WAs do not perform any operation that produces an output. Hereinafter, a row of optical sensors WAs aligned along the first direction Dx where all optical sensors WAs are located outside the circle 311 will be referred to as a row of non-operating optical sensors WAs. Specifically, no gate signal is supplied to the scan line 6 shared by multiple optical sensors WAs in a row of non-operating optical sensors WAs. No output is transmitted via the signal line 7 from optical sensors WAs connected to the scan line 6 where no gate signal is supplied. Therefore, the detection circuit 15 does not receive an output from optical sensors WAs connected to the scan line 6 where no gate signal is supplied. In Figure 14, among the rows of optical sensors WA arranged in the y direction, the rows of optical sensors WA included in the non-operating range 410 and the rows of optical sensors WA included in the non-operating range 420 correspond to rows of optical sensors WA that are not operating.

[0071] On the other hand, in rows where one or more of the optical sensors WAs arranged along the first direction Dx are located inside the circle 301, the optical sensors WAs perform an operation that generates an output. Hereinafter, rows where one or more of the optical sensors WAs arranged along the first direction Dx are located inside the circle 301 will be referred to as rows of operational optical sensors WAs. As mentioned above, the degree of light detection indicated by the output outside the circle 311 is not used to detect the occurrence of a colony. Therefore, in this embodiment, the treatment of each output of the multiple optical sensors WAs included in the row of operational optical sensors WAs differs depending on whether they are located inside the circle 301 or outside the circle 311. Specifically, the output of optical sensors WAs located outside the circle 311 among the multiple optical sensors WAs included in the row of operational optical sensors WAs is ignored. On the other hand, the output of optical sensors WAs located inside the circle 301 among the multiple optical sensors WAs included in the row of operational optical sensors WAs is reflected in the image.

[0072] It is sufficient to predetermine whether the optical sensor WA overlapping with circle 212 is treated as either inside the circle 301 or outside the circle 311, and this can be changed as appropriate. By treating the optical sensor WA overlapping with circle 212 as inside the circle 301, colonies that are in contact with or very close to the outer wall of dish 210 can be detected with higher accuracy. On the other hand, by treating the optical sensor WA overlapping with circle 212 as outside the circle 311, even if a dark area is created by a water droplet 240 that is in contact with the outer wall of dish 210 from the outside, it is possible to suppress with higher accuracy the misidentification of this dark area as a dark area caused by a colony.

[0073] Furthermore, in this embodiment, it is necessary to obtain the circle 211 that will become the circle 212 in order to distinguish between the inside 301 and the outside 311 of the circle. For this reason, for the first scan, all rows of optical sensors WA are treated as rows of operational optical sensors WA. That is, in the first scan, the output from all optical sensors WA is transmitted to the detection circuit 15. The control circuit 30 of this embodiment obtains an image corresponding to the entire detection area SA from the output of the optical sensors WA obtained in the first scan via the detection circuit 15. The control circuit 30 performs various extraction processes such as the contour extraction process and Hough transform described above on the image to obtain the circle 211. In this way, the control circuit 30 extracts the circumferential contour (circle 211) that the edge of the dish 210 creates in the image as a boundary line.

[0074] As explained with reference to Figure 4, the light source 22 includes a first light source 22R, a second light source 22G, and a third light source 22B. In this embodiment, the first light source 22R, the second light source 22G, and the third light source 22B are each lit at different timings. In this embodiment, a scan process to detect light from the first light source 22R with the light sensor WA, a scan process to detect light from the third light source 22B with the light sensor WA, and a scan process to detect light from the second light source 22G with the light sensor WA are performed separately. Note that a scan process is a process to obtain an image. For example, in the scan process to detect light from the first light source 22R with the light sensor WA, the light emitted when the first light source 22R is lit passes through the object to be detected 200 and is detected by the light sensor WA provided in the detection area SA of the planar light sensor 10. The output of the light sensor WA resulting from this is treated as a pixel of the image.

[0075] In this embodiment, the initial scan process described above is, for example, a scan process in which the light sensor WA detects light from the first light source 22R. However, the initial scan process may also be a scan process in which the light sensor WA detects light from the second light source 22G or a scan process in which the light sensor WA detects light from the third light source 22B.

[0076] Furthermore, if the outer periphery wall of dish 210 has thickness, the inner and outer surfaces of the periphery wall may be extracted as separate rings during the contour extraction process and Hough transform. Even in this case, the inside of the innermost circumference among the multiple circumferences obtained by the Hough transform is treated as the inside of dish 210, so the explanation with reference to Figures 12 to 14 can be applied as is.

[0077] Next, the processing flow related to the operation of the detection device 1 will be explained with reference to the flowcharts in Figures 15 to 17. Unless otherwise noted, in this embodiment, the control circuit 30 is the main control unit for the processing of each step shown in the flowcharts in Figures 15 to 17.

[0078] Figure 15 is a flowchart showing the processing flow related to the operation of the detection device 1. First, the initial operation is performed (step S1). At the time of the initial processing, it is assumed that the object to be detected 200 has just been placed in the detection device 1. In other words, at the time of the initial processing, it is assumed that no colonies have formed in the culture medium 215.

[0079] Figure 16 is a flowchart showing the flow of the initial processing. First, the brightness of the first light source 22R is automatically adjusted (step S11). The automatic brightness adjustment in step S11 and in steps S16 and S20, which will be described later, is the process of adjusting the brightness of multiple identical color light sources provided in the light-emitting region LA to a predetermined brightness. Here, we will explain as an example the case in which the automatic brightness adjustment of multiple first light sources 22R is performed in step S11. In this example, the multiple first light sources 22R start operating at either the lowest brightness or the highest brightness, and their operation is controlled so that the brightness changes towards the other of the lowest or highest brightness as time progresses. During this time, light detection and output of multiple photons WA provided in the detection region SA are performed periodically. Here, the brightness of the first light source 22R at the point when the output of the photons WA corresponds to the predetermined brightness is treated as the predetermined brightness.

[0080] In the embodiment, step S11 involves individually adjusting the brightness of multiple first light sources 22R. Specifically, a correspondence is established between the light sensor WA and the first light sources 22R in advance, determining which first light source 22R's brightness corresponds to a predetermined brightness when the output of the light sensor WA reaches a predetermined brightness. More specifically, a light sensor WA detects light from a first light source 22R associated with that particular light sensor WA more strongly than light from other first light sources 22R. In other words, the associated first light sources 22R and light sensor WA are positioned to overlap or nearly overlap in a planar viewpoint. By determining the brightness of the first light sources 22R in this way, the automatic brightness adjustment is completed.

[0081] In step S11, and in steps S16 and S20 described later, the control circuit 30 operates the planar light sensor 10 and the light source panel 20 to perform automatic brightness adjustment.

[0082] By replacing the first light source 22R with the second light source 22G in the explanation of the process in step S11, the explanation of the process in step S16 will be described later. Also, by replacing the first light source 22R with the third light source 22B in the explanation of the process in step S11, the explanation of the process in step S20 will be described later. Furthermore, the specific flow of automatic brightness adjustment exemplified here is merely an example and is not limited to this; as long as the brightness of multiple identical color light sources can be set to a predetermined brightness, the details may be changed as appropriate.

[0083] After the processing in step S11, a scanning process is performed using light from the first light source 22R (step S12). Specifically, the control circuit 30 operates the planar light sensor 10 and the light source panel 20 to perform the scanning process. In the process of step S12, the light source that lights up due to the operation of the light source panel 20 is the first light source 22R. In the process of step S12, the second light source 22G and the third light source 22B do not light up. As a result, the control circuit 30 obtains an image corresponding to the output of multiple light sensors WA that detected light from the first light source 22R that has passed through the object to be detected 200. Upon completion of the process in step S12, the first light source 22R turns off (step S13).

[0084] Furthermore, in the process of step S17 described later, the light source that is lit will be the second light source 22G instead of the first light source 22R. Also, in the process of step S21 described later, the light source that is lit will be the third light source 22B instead of the first light source 22R.

[0085] After the processing in step S12 and step S13, the mask processing area is determined (step S14). Specifically, the control circuit 30 performs various extraction processes such as the contour extraction process and Hough transform described above on the image obtained in the scan process of step S12. This obtains circumferences corresponding to the contours of each structure, such as circles 211, 231, and 950 as explained with reference to Figure 12. The control circuit 30 then sets the area outside the smallest circumference among the obtained circumferences as the mask processing area. In the example shown in Figure 13, the mask processing area is the area outside the circle 311. The control circuit 30 does not use the output of the optical sensor WA corresponding to the mask processing area for the colony detection process. That is, as explained with reference to Figure 14, the output of the area outside the circle 311 is not used for the colony detection process. As a result of the processing in step S14, the detection of light by the planar optical sensor 10 is limited to the area inside the circle 301, which detects light that has passed through the inside of the dish 210. Thus, the process in step S14 includes extracting the circumferential contour (circle 211) created by the edge of the dish 210 in the image as a boundary line.

[0086] After processing in step S14, the first data is output (step S15). The first data is image data that reflects the output of the optical sensor WA located inside the circle 301 (see Figure 14) but does not reflect the output of the optical sensor WA located outside the circle 311, and is image data obtained from light from the first light source 22R. Specifically, the control circuit 30 treats the output of the optical sensor WA located inside the circle 301 as pixels, and ignores the output of the optical sensor WA located outside the circle 311, and uses the resulting image data as the first data.

[0087] After the processing in step S15, the brightness of the second light source 22G is automatically adjusted (step S16). After the processing in step S16, a scanning process is performed using light from the second light source 22G (step S17). Specifically, the scanning process is performed by the control circuit 30 operating the planar light sensor 10 and the light source panel 20. In the processing of step S17, the light source that lights up due to the operation of the light source panel 20 is the second light source 22G. In the processing of step S17, the first light source 22R and the third light source 22B do not light up. As a result, the control circuit 30 obtains an image corresponding to the output of multiple light sensors WA that detected light from the second light source 22G that has passed through the object to be detected 200. Upon completion of the processing in step S17, the second light source 22G is turned off (step S18).

[0088] After the processing in step S17 and step S18, the second data is output (step S19). The second data is image data that reflects the output of the optical sensor WA located inside the circle 301 (see Figure 14) but does not reflect the output of the optical sensor WA located outside the circle 311, and is image data obtained from light from the second light source 22G. Specifically, the control circuit 30 treats the output of the optical sensor WA located inside the circle 301 as pixels, and ignores the output of the optical sensor WA located outside the circle 311, and uses this image data as the second data.

[0089] After the processing in step S19, the brightness of the third light source 22B is automatically adjusted (step S20). After the processing in step S20, a scanning process is performed using light from the third light source 22B (step S21). Specifically, the control circuit 30 operates the planar light sensor 10 and the light source panel 20 to perform the scanning process. In the processing of step S21, the light source that lights up due to the operation of the light source panel 20 is the third light source 22B. In the processing of step S21, the first light source 22R and the second light source 22G do not light up. As a result, the control circuit 30 obtains an image corresponding to the output of multiple light sensors WA that detected light from the third light source 22B that has passed through the object to be detected 200. Upon completion of the processing in step S21, the third light source 22B is turned off (step S22).

[0090] After the processing in step S21 and step S22, the second data is output (step S23). The second data is image data that reflects the output of the optical sensor WA located inside the circle 301 (see Figure 14) but does not reflect the output of the optical sensor WA located outside the circle 311, and is image data obtained by light from the third light source 22B. The control circuit 30 treats the output of the optical sensor WA located inside the circle 301 as pixels, and ignores the output of the optical sensor WA located outside the circle 311 to obtain the image data as the third data.

[0091] The initial operation ends upon completion of the first step S23. As shown in Figure 15, after the initial operation, which is the process of step S1, timing by a timer begins (step S2). The process of step S2 may be carried out by, for example, a timer circuit provided in the control circuit 30, or by setting a variable that functions as a counter and updating the counter based on the operating clock of the control circuit 30, or by other methods.

[0092] After the start of timing by the process in step S2, a check is performed to see if a predetermined time has elapsed (step S3). The control circuit 30 waits without performing the next process until the predetermined time has elapsed (step S3; No). The predetermined time is, for example, 5 minutes, but is not limited to this. The predetermined time may be appropriately determined according to the period (time interval) for which it is necessary to determine whether a colony has formed. After the process in step S2, once the predetermined time has elapsed (step S3; Yes), a periodic operation is performed (step S4).

[0093] Figure 17 is a flowchart showing the flow of a periodic operation. A periodic operation is an operation in which the processes in steps S11, S14, S16, and S20 of the various processes included in the initial operation, as explained with reference to Figure 16, are omitted. In a periodic operation, the processes are carried out in the following order: steps S12, S13, S15, S17, S18, S19, S21, S22, and S23.

[0094] The first light source 22R, the second light source 22G, and the third light source 22B are each illuminated at different timings. Furthermore, while one of the first light source 22R, the second light source 22G, or the third light source 22B is illuminated, the other two remain unlit. These light sources are also illuminated periodically in the order of the first light source 22R, the second light source 22G, and the third light source 22B. These are demonstrated in the processing of steps S12, S13, S17, S18, S21, and S22 during the initial operation and periodic operation.

[0095] The brightness of the first light source 22R, which lights up during periodic operation, is the brightness adjusted by the automatic brightness adjustment process in step S11 of the initial operation. The brightness of the second light source 22G, which lights up during periodic operation, is the brightness adjusted by the automatic brightness adjustment process in step S16 of the initial operation. The brightness of the third light source 22B, which lights up during periodic operation, is the brightness adjusted by the automatic brightness adjustment process in step S20 of the initial operation. In the processes of steps S15, S19, and S23 of the periodic operation, the mask processing range determined by the process in step S14 is applied. That is, in the processes of steps S15, S19, and S23 of the periodic operation, the distinction between the inside of the circle 301 and the outside of the circle 311 is made in accordance with the result of the process in step S14, just as in the initial operation.

[0096] Therefore, it can be said that in step S14, the control circuit 30 extracts the circle 211 included in the image output in response to the first illumination of the first light source 22R during the initial operation as a boundary line. Furthermore, when the second light source 22G, the third light source 22B, and the first light source 22R are illuminated for the second time and beyond, the control circuit 30 does not provide a gate signal to a specific scan line 6, as explained with reference to Figure 14. The specific scan line 6 referred to here is the scan line 6 to which only the optical sensor WA that produces an output reflected outside the boundary line in the image is connected. In Figure 14, the scan lines 6 provided in the row of optical sensor WA included in the non-operating range 410 and the row of optical sensor WA included in the non-operating range 420 correspond to the specific scan line 6. Note that in the initial operation, the same processing as in step S14 may be performed for each of the second light source 22G and the third light source 22B.

[0097] The periodic operation ends upon completion of the second and subsequent steps S23. As shown in Figure 15, after the periodic operation in step S4, the timer is reset (step S5). That is, the timer, which started timing in step S2, is reset in step S5.

[0098] Furthermore, the control circuit 30 determines whether a colony has formed based on the change in brightness between the data obtained in the initial operation and the data obtained in the periodic operation (step S6). Specifically, the control circuit 30 compares the t-th data obtained in the initial operation with the t-th data obtained in the periodic operation. If the control circuit 30 finds a dark area in the t-th data obtained in the periodic operation that is not present in the t-th data obtained in the initial operation, it determines that the dark area is due to a colony. Here, t in the t-th data is one of 1, 2, or 3. To illustrate the case where t is 1, "The control circuit 30 compares the first data obtained in the initial operation with the first data obtained in the periodic operation. If the control circuit 30 finds a dark area in the first data obtained in the periodic operation that is not present in the first data obtained in the initial operation, it determines that the dark area is due to a colony." The same interpretation applies to the cases of t=2 or t=3. The control circuit 30 determines the cases of t=1, t=2, and t=3 individually. The size at which a dark area is treated as a colony is predetermined and can be changed as appropriate depending on the size of the colony targeted for notification by the notification process described later. Furthermore, the processing in step S6 is not limited to comparing the t-th data obtained in the initial operation with the t-th data obtained in the periodic operation. For example, the t-th data obtained in the latest periodic operation may be compared with the t-th data obtained in the periodic operation immediately preceding it, and if a new dark area appears in the t-th data obtained in the latest periodic operation, it may be determined that the dark area is due to a colony.

[0099] Furthermore, in this embodiment, if a dark area that can be identified as a colony is present in one or more of the cases t=1, t=2, and t=3, it is treated as if a colony has been determined to have occurred in step S6. However, the specific conditions for such determination are not limited to these. If a dark area that can be identified as a colony is present in two or more or all three of the cases t=1, t=2, and t=3, it may be determined in step S6 that a colony has been determined to have occurred. Step S6 corresponds to a determination process that determines whether a colony has occurred based on a comparison of multiple images obtained at different timings. Here, in the processes of steps S15, S19, and S23 described above, the output of the optical sensor WA reflected outside the boundary circle 211 is excluded from each image.

[0100] If it is determined in step S6 that a colony has formed (step S6; Yes), a notification process is performed (step S7). In the notification process, notification is performed using a predetermined notification method. In this embodiment, the execution of the notification process sends an email indicating that a colony has formed to the email address of the administrator of the detected object 200. The email and the text sent in the email are predetermined. In this embodiment, for example, the control circuit 30 functions as the entity that sends the email, but it is not limited to this. As another example, the control circuit 30 may output a signal to an external information processing device that functions as a command to send an email, or it may be done by other means. Furthermore, the form of notification performed in the notification process is not limited to sending an email. For example, an audio output device such as a speaker may be operated to output a predetermined "sound to notify that a colony has formed," or it may be a notification in another form.

[0101] If it is determined in step S6 that no colonies have formed (step S6; No), the process proceeds to step S2 unless the operation of the detection device 1 has finished (step S8; No). That is, the timer starts again, and each time a predetermined amount of time has elapsed, periodic operation, timer reset, and determination of whether colonies have formed are performed. If the operation of the detection device 1 finishes in step S8 (step S8; Yes) and after the execution of step S7, the process related to the operation of the detection device 1 ends.

[0102] As described above, according to the embodiment, the detection device 1 comprises a light source (light source 22) that emits light, a planar light sensor (planar light sensor 10) in which a plurality of light sensors (light sensors WA) that detect light from the light source are arranged two-dimensionally, a detection object installation unit (detection object installation unit 99) provided so that a detection object (detection object 200) can be installed between the light source and the planar light sensor, and a processing unit (control circuit 30) that controls the operation of the light source and the planar light sensor and processes based on the outputs of the plurality of light sensors. The detection object is a culture medium (culture medium 215) contained in a container dish (dish 210). The planar light sensor outputs data that reflects the intensity of light emitted from the light source that passes through the detection object and reaches the plurality of light sensors. The processing unit performs an extraction process to extract a circumferential contour (circle 211) created by the edge of the dish in the data as a boundary line, and a determination process to determine whether colonies have formed in the culture medium based on a comparison of multiple data obtained at different time points. In the determination process, the output of the optical sensor reflected outside the boundary line is excluded from each of the data. The boundary line is the smallest of one or more circumferential contours (circles 211, 231, and 950) included in the data. This suppresses the influence of the optical sensor output reflected at the boundary line in the determination process. In other words, even if condensation occurs outside the dish, the optical effect of the water droplets from the condensation on the data does not affect the determination process. Therefore, it is possible to suppress false detection of colonies due to confusion between the dark areas created in the data by the water droplets and the dark areas created in the data by the colonies. Thus, according to this embodiment, colonies can be detected with higher accuracy.

[0103] Furthermore, in this embodiment, the container also has a lid (lid 220). The lid has a cylindrical outer wall that covers the cylindrical outer wall of the dish (dish 210) from the outside. The extraction process performed by the processing unit (control circuit 30) includes a Hough transform. This extraction process extracts the outer walls of the dish and the lid as circumferential contours. The boundary line is then the smallest of the one or more circumferential contours included in the data. Thus, even with a configuration in which multiple circumferential contours are extracted from the object to be detected, the optical effect of water droplets due to condensation on the outside of the dish on the data does not affect the determination process. Therefore, colonies can be detected with higher accuracy.

[0104] Furthermore, in this embodiment, the object to be detected mounting section (object to be detected mounting section 99) includes a light-transmitting member (light-transmitting member 91) on which the object to be detected is placed, and a light-shielding member (light-shielding member 92) that supports the light-transmitting member from its outer circumference. This prevents optical changes from being reflected in the output of the planar light sensor even if optical changes occur outside the light-shielding member due to changes over time or the like. In other words, it is possible to suppress false detection of colonies due to optical changes occurring outside the light-shielding member.

[0105] Furthermore, in this embodiment, the diameter of the circle drawn by the boundary between the light-transmitting member (light-transmitting member 91) and the light-shielding member (light-shielding member 92) is larger than the diameter of the circle drawn by the edge of the dish (dish 210), thereby suppressing the influence of the light-shielding member (light-shielding member 92) on the light passing through the dish.

[0106] Furthermore, the planar light sensor (planar light sensor 10) in the embodiment has a scanning line (scanning line 6) that transmits a gate signal to generate an output to a light sensor (light sensor WA) along a first direction (first direction Dx), and a signal line (signal line 7) that transmits the output of the light sensor along a second direction (second direction Dy) perpendicular to the first direction, with multiple light sensors arranged in a matrix. Furthermore, the light source (light source 22) in the embodiment has a first light source (first light source 22R) that emits light of a first color, a second light source (second light source 22G) that emits light of a second color, and a third light source (third light source 22B) that emits light of a third color. In this embodiment, the first light source, the second light source, and the third light source are lit at different timings, and while one of the first, second, or third light sources is lit, the other two remain off. The first, second, and third light sources are lit periodically in that order. The processing unit (control circuit 30) extracts the boundary line contained in the data output in response to the first lighting of the first light source. When the second, third, and first light sources are lit for the second time and onward, gate signals are not applied to scan lines connected only to optical sensors that produce outputs reflected outside the boundary line in the data. This allows the circumferential contour (circle 211) created by the edge of the dish (dish 210) in the data to be extracted as a boundary line with minimal processing, and the boundary line can be shared in subsequent data processing. Furthermore, by not applying gate signals to scan lines connected only to optical sensors that produce outputs reflected outside the boundary line, the data can be made smaller compared to the case where gate signals are applied to all scan lines. Therefore, the processing load of image processing related to the judgment process can be further reduced. In addition, because there are scan lines that are not given a gate signal, the time required for data output can be shortened compared to when a gate signal is given to all scan lines. Furthermore, because there are scan lines that are not given a gate signal, power consumption can also be reduced compared to when a gate signal is given to all scan lines.

[0107] Furthermore, in this embodiment, the first color of light emitted by the first light source (first light source 22R) is red light, the first color of light emitted by the second light source (second light source 22G) is green light, and the first color of light emitted by the third light source (third light source 22B) is blue light, thereby obtaining data corresponding to the three light colors that constitute the so-called RGB image data. Consequently, it becomes easier to more reliably capture the optical effects that colonies produce on the culture medium.

[0108] Furthermore, as shown in Figure 7, when the object to be detected 200 is placed on the light-transmitting member 91 with the dish 210 containing the culture medium 215 positioned relatively above and the lid 220 positioned relatively below, it is possible to suppress condensation caused by moisture evaporated from the culture medium 215 moving upward. This also helps to suppress drying of the culture medium 215 and to obtain better images of the culture medium 215.

[0109] In this embodiment, a light source 22 having a first light source 22R, a second light source 22G, and a third light source 22B is used as the light source, but the light sources that can be used in the form of this disclosure are not limited to this. For example, a light source corresponding to four or more colors of light may be used, or a light source corresponding to one or two colors of light may be used. In addition, light of a composite color obtained by simultaneously lighting some or all of multiple types of light sources that emit light of different colors may be used. For example, when the first light source 22R, the second light source 22G, and the third light source 22B are lit simultaneously, white light can be obtained.

[0110] Furthermore, the relative vertical relationship between the planar light sensor 10 and the light source panel 20 is not limited to the example shown in Figure 7, and may be the reverse of that. Also, the elastic member 93 is not essential for the object to be detected mounting section 99. For example, the light-transmitting member 91 may be interposed between the planar light sensor 10 and the light source panel 20 by fixing the light-shielding member 92 to the housing 90. In this case, a gap into which the object to be detected 200 can be inserted is provided above the light-transmitting member 91 between the planar light sensor 10 and the light source panel 20.

[0111] Furthermore, while a lid 220 is not essential for the detected object 200, it is more desirable to provide one in order to prevent foreign matter from entering the culture medium 215. Also, although the dish 210 in this embodiment is a Petri dish, it is not limited to this, and other configurations that function similarly may be used.

[0112] Furthermore, any other effects and advantages brought about by the embodiments described herein that are obvious from this specification or that can be appropriately conceived by those skilled in the art are naturally provided by this disclosure. [Explanation of Symbols]

[0113] 1. Detection device 6 scan lines 7 Signal lines 10 Planar light sensor 22 Light source 22R 1st light source 22G 2nd light source 22B 3rd light source 30 Control circuits 91 Light-transmitting member 92 Light-shielding material 95 yen 99 Detected object installation section 210 dishes 220 Lid 211 yen 215 Culture medium WA Optical Sensor

Claims

1. A light source that emits light, A planar light sensor in which multiple light sensors for detecting light from the aforementioned light source are arranged in a two-dimensional manner, A detection object installation unit is provided so as to be able to install the detection object between the light source and the planar light sensor, The system includes a processing unit that controls the operation of the light source and the planar light sensor, and processes based on the outputs of the multiple light sensors, The object to be detected is a culture medium contained in a container dish. The planar light sensor outputs data that reflects the intensity of light emitted from the light source, passing through the object to be detected and reaching the multiple light sensors. The aforementioned processing unit, An extraction process that extracts the circumferential contour created by the edge of the dish in the data as a boundary line, A determination process is performed to determine whether colonies have formed in the culture medium based on a comparison of multiple data obtained at different time points. In the determination process, the output of the light sensor reflected outside the boundary line is excluded from each of the multiple data points. Detection device.

2. The aforementioned container further has a lid, The lid has a cylindrical outer wall that covers the cylindrical outer wall of the dish from the outside, The extraction process includes a Hough transform, The extraction process extracts the outer periphery walls of the dish and the lid as a circular contour. The boundary line is the smallest of one or more circumferential contours included in the data. The detection device according to claim 1.

3. The object to be detected installation unit is, A light-transmitting member on which the object to be detected is placed, The light-transmitting member has a light-shielding member that supports it from the outer circumference, The boundary between the light-transmitting member and the light-shielding member forms a circle. The detection device according to claim 1 or 2.

4. The diameter of the circle traced by the aforementioned boundary is greater than the diameter of the circle traced by the edge of the dish. The detection device according to claim 3.

5. The planar light sensor is provided along a first direction and has a scan line that transmits a gate signal that generates an output to the light sensor, and a signal line that transmits the output of the light sensor along a second direction perpendicular to the first direction, with multiple light sensors arranged in a matrix. The aforementioned light source is A first light source that emits light of a first color, A second light source that emits a second color of light, It has a third light source that emits light of a third color, The first light source, the second light source, and the third light source are each turned on at different timings. While one of the first light source, the second light source, or the third light source is lit, the other two remain off. The first light source, the second light source, and the third light source are periodically illuminated in that order. The processing unit extracts the boundary line included in the data output in response to the first lighting of the first light source, When the second light source, the third light source, and the first light source are turned on for the second time or later, the gate signal is not applied to the scan line to which only the light sensor that produces an output reflected outside the boundary line of the data is connected. The detection device according to claim 1 or 2.

6. The first color of light is red light, The first color of light is green light, The first color of light is blue light. The detection device according to claim 5.

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