Detection device

Abstract

To provide a detection device capable of suppressing deterioration in sensing accuracy.SOLUTION: The detection device includes a sensor panel in which a plurality of optical sensors are arranged, a light source, and a control circuit. The detection target placed between the sensor panel and the light source is provided with a culture medium capable of culturing colonies. The control circuit repeats an acquisition process of obtaining outputs of the plurality of optical sensors, and performs a comparison process of comparing a first output obtained in a first acquisition process with a second output obtained in a latest acquisition process. The comparison processing includes first comparison processing for comparing the outputs of the respective optical sensors, and second comparison processing for comparing the outputs of the respective optical sensors in a region unit including a certain optical sensor and its peripheral optical sensors. The control circuit determines that the output of the optical sensor having the difference equal to or larger than the predetermined value in the first comparison processing and having the difference equal to or larger than the predetermined value in the second comparison processing with the optical sensor satisfying the first condition as one optical sensor is the output of the optical sensor overlapping the colony.SELECTED DRAWING: Figure 9

Description

[Technical Field]

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

[0002] BACKGROUND ART There is known a detection device that can detect the state of a culture environment in which biological tissues or microorganisms are cultured using an optical sensor (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-87005 Summary of the Invention [Problem to be solved by the invention]

[0004] Sensing of the culture environment using a detection device such as that described in Patent Document 1 is based on the tendency for the brightness of light detected by an optical sensor to decrease as the culture of the culture object progresses. Here, foreign matter such as dust may be introduced into the Petri dish containing the medium in which the culture object is cultured. If such foreign matter moves during the culture, the decrease in brightness of light caused by the shadow cast by the foreign matter may be confused with an increase in the number of culture objects due to the culture progress. This confusion contributes to a decrease in the accuracy of sensing the culture progress of the culture object. Therefore, there has been a need for a mechanism that can better suppress the decrease in the accuracy of sensing the culture progress of the culture object, which is caused by confusing the movement of foreign matter with an increase in the number of culture objects.

[0005] The present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a detection device that can suppress a decrease in sensing accuracy. [Means for solving the problem]

[0006] A detection device according to one aspect of the present disclosure includes a sensor panel having a detection area in which a plurality of optical sensors are two-dimensionally arranged, a light source that emits light, a member provided so that a detectable object can be placed between the detection area and the light source, and a control circuit that controls the operation of the sensor panel and the light source and performs processing based on outputs from the plurality of optical sensors, wherein the detectable object is provided with a culture medium capable of cultivating colonies, and the control circuit operates the light source after the detectable object is placed to generate light toward the sensor panel and perform an acquisition process to acquire an output from the sensor panel corresponding to the intensity of the light detected by the plurality of optical sensors, and repeats the acquisition process at predetermined waiting times, and acquires a first output which is the output from the sensor panel obtained in the initial acquisition process and a second output which is the output from the sensor panel obtained in the latest acquisition process. and a second output of the optical sensor that is located adjacent to the colony, the first output being a difference of at least a predetermined value between the first output and the second output, and the second output being a difference of at least a predetermined value between the first output and the second output, the first output being a difference of at least a predetermined value between the first output and the second output, and the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the second output and the second output, the first output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the second ... second output and the second output, the second output being a difference of at least a predetermined value between the second output and the second output, the first output being a difference of at least a predetermined value between the first output and the second output, the second output being a difference of at least a predetermined value between the second output and the second output, the second output being a difference of at least [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a diagram showing the main configuration of the detection device. [Figure 2] FIG. 2 is a diagram showing an example of the configuration of the detection area and the wiring area. [Figure 3] FIG. 3 is a circuit diagram showing the circuit configuration of the optical sensor. [Figure 4] FIG. 4 is a schematic diagram illustrating an example of the configuration of a detection system. [Figure 5] FIG. 5 is a schematic diagram showing the relationship between one detection device and an external configuration. [Figure 6] FIG. 6 is a schematic diagram showing the positional relationship between the main components of the detection device and the object to be detected. [Figure 7] FIG. 7 is a schematic diagram showing, in plan view, an object illuminated with light from a sensor panel. [Figure 8] FIG. 8 is a schematic diagram showing an outline of the colony detection method. [Figure 9] FIG. 9 is a schematic diagram showing the basic mechanism for distinguishing between a differential region due to a foreign substance and a differential region due to colony expansion. [Figure 10] FIG. 10 is a schematic diagram showing a more advanced mechanism for distinguishing between differential regions due to foreign matter and differential regions due to colony expansion. [Figure 11] FIG. 11 is a diagram showing weighting coefficients for the first unit region and the second unit region when all of the plurality of pixels are treated equally. [Figure 12] FIG. 12 is a diagram showing an example of weighting coefficients when weighting a plurality of pixels included in the first unit area and the second unit area individually. [Figure 13] FIG. 13 is a flowchart showing the flow of processing performed by the detection device when the values ​​of M and N in equation (2) are fixed. [Figure 14] FIG. 14 is a flowchart showing the flow of processing performed by the detection device when the values ​​of M and N in equation (2) are changed. [Figure 15] FIG. 15 is a schematic diagram showing an example of the configuration of the light source 22. As shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0008] Each embodiment of the present disclosure will be described below with reference to the drawings. The disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily conceive while maintaining the gist of the invention are naturally included within the scope of the present disclosure. Furthermore, to clarify the explanation, the drawings may show the width, thickness, shape, etc. of each part schematically compared to the actual embodiment, but these are merely examples and are not intended to limit the interpretation of the present disclosure. Furthermore, in this specification and each drawing, elements similar to those described above with reference to the previous drawings will be designated by the same reference numerals, and detailed descriptions may be omitted as appropriate.

[0009] 1 is a diagram showing the main configuration of a detection device 1. The detection device 1 includes a sensor panel 10, a light source panel 20, and a control circuit 30. The sensor panel 10 and the light source panel 20 of the detection device 1 are connected to the control circuit 30.

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

[0011] The light source panel 20 has a light emitting area LA that irradiates the detection area SA with light. The light source panel 20 has a light source 22 provided on a substrate 21. The light source 22 has a light emitting element such as an LED (Light Emitting Diode) and is arranged in the light emitting area 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 controls whether each of the plurality of light sources 22 is turned on and the brightness when turned on under the control of the control circuit 30. The plurality of light sources 22 may be provided so that their light emission can be controlled individually, or may be provided so that they 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 multiple functions, such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit). The control circuit 30 is connected to the detection circuit 15 via a wiring unit 19, and receives output from the detection circuit 15. The control circuit 30 is also connected to the light source drive circuit 23 via a wiring unit 29, and performs processes related to the lighting of the light source 22, such as determining the lighting pattern of the light source 22.

[0014] The control circuit 30 also performs processing related to the detection of colonies in the detection object SUB (see FIG. 5), which will be described later.

[0015] Although not shown, the detection device 1 is equipped with an analog-to-digital conversion circuit, a digital-to-analog conversion circuit, etc. The analog-to-digital conversion circuit enables the output from the optical sensor WA (see FIG. 2) transmitted via the detection circuit 15 to be handled by the arithmetic processing by the control circuit 30. The digital-to-analog conversion circuit enables the digital signal generated by the arithmetic processing by the control circuit 30 to be used to control the operation of the sensor panel 10 and the light source panel 20. For example, some or all of these circuits may be included in the control circuit 30, or may be functions performed by circuits mounted on flexible printed circuits (FPCs) provided as wiring units 19 and 29, or may be mounted in the detection device 1 by other methods.

[0016] FIG. 2 is a diagram showing an example of the configuration of the detection area SA and wiring area VA. A plurality of optical sensors WA (FIG. 3) are provided in the detection area SA. In the embodiment, as shown in FIG. 2, the plurality of 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 to each other. In the following description, the third direction Dz refers to a 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, ..., 5r. Hereinafter, the reset signal transmission line 5 refers to any one of the reset signal transmission lines 51, 52, ..., 5r. The reset signal transmission line 5 is wiring that runs along the first direction Dx. In the example shown in FIG. 2, r reset signal transmission lines 5 are arranged in the second direction Dy, where r is a natural number greater than or equal to 2. The r reset signal transmission lines 5 are connected to the reset circuit 13 at one end in the first direction Dx.

[0018] The scanning circuit 14 is connected to the scanning lines 61, 62, ..., 6r. Hereinafter, when a scanning line 6 is described, it refers to any one of the scanning lines 61, 62, ..., 6r. The scanning lines 6 are wirings that run along the first direction Dx. In the example shown in FIG. 2, r scanning lines 6 are arranged in the second direction Dy. The r scanning lines 6 are connected to the scanning circuit 14 at the other end side in the first direction Dx.

[0019] 2, the reset signal transmission lines 5 and the scanning lines 6 are arranged alternately in the second direction Dy within the detection area SA. Note that, although the reset circuit 13 and the scanning circuit 14 illustrated in FIGS. 1 and 2 are arranged in opposing positions across the detection area SA, the layout of the reset circuit 13 and the scanning circuit 14 is not limited to this and can be changed as appropriate.

[0020] Furthermore, signal lines 71, 72, ..., 7q are provided within the detection area SA. Hereinafter, the term "signal line 7" refers to any one of the signal lines 71, 72, ..., 7q. The signal line 7 is a wiring that extends along the second direction Dy.

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

[0022] The multiplexer 40 is provided within the wiring area VA. The multiplexer 40 has a plurality of switches. In the example shown in FIG. 2, the switches are SW1, SW2, SW3, and SW4. The switches included in one multiplexer 40 are turned ON (conductive) at different times. When one of the switches included in one multiplexer 40 is ON (conductive), the other switches are OFF (non-conductive). The number of multiplexers 40 depends on the number (q) of signal lines 7. If the number of switches is p, then the number of multiplexers 40 must be q / p. When there are multiple multiplexers 40, each of the multiple multiplexers 40 is connected to the detection circuit 15 via individual wirings 401, 402, . . . , 40p.

[0023] Note that the connection between the signal lines 7 and the detection circuits 15 via the multiplexer 40 is merely an example and is not limiting; the signal lines 7 may be individually connected directly to the detection circuits 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 141.

[0024] The detection circuit 15 is involved in the detection of light by the PD82 (see FIG. 3) provided in the optical sensor WA, and controls the operation timing of the reset circuit 13 and the scanning circuit 14. The output from the optical sensor WA is also input to the detection circuit 15. 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 the data to the control circuit 30. The detection circuit 15 in this embodiment is an MCU (Micro Controller Unit).

[0025] Fig. 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 Fig. 3 merely correspond to the directions of the reset signal transmission line 5, the scanning line 6, and the signal line 7, and do not strictly represent the relative positional relationship of the circuit configuration within the optical sensor WA.

[0026] 3, the optical sensor WA includes a switching element 81, a PD 82, a transistor element 83, and a switching element 85. The PD 82 is a photodiode (PD: PhotoDiode). The switching elements 81 and 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 one of 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 of the source or drain of the switching element 81. Hereinafter, the connection point CP refers to the point where the other, that is, the cathode of PD82 and the gate of transistor element 83, are connected. A reference potential VCOM is 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. The reset potential VReset is a potential higher than the reference potential VCOM.

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

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

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

[0031] When the gate of the switching element 85 is turned ON by a 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. Hereinafter, the term "scanning signal" 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 scanning signal.

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

[0033] Fig. 4 is a schematic diagram showing an example of the configuration of a detection system 100 provided as a configuration including a detection device 1. As shown in Fig. 4, the detection system 100 has 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 the common host IC 70 via the connection circuit 125.

[0034] 4 is maintained in an environment (temperature, humidity, etc.) suitable for culturing colonies in the detection object SUB with the door closed. A plurality of detection devices 1 are placed inside the incubator 120. The detection object SUB is provided with a culture medium capable of culturing colonies.

[0035] Fig. 5 is a schematic diagram showing the relationship between one detection device 1 and an external configuration. As shown in Fig. 5, the detection device 1 and the connection circuit 125 are connected by the connection between the control circuit 30 and the connection circuit 125. Also, as shown in Fig. 5, the sensor panel 10 and the light source panel 20 face each other. Furthermore, a gap is provided between the sensor panel 10 and the light source panel 20 in which the object to be detected SUB can be placed.

[0036] The subject SUB is made of a light-transmitting material, and a culture medium is formed on its upper surface. The culture medium is a medium capable of culturing colonies. The term "colony" simply refers to a colony of biological tissue or microorganisms cultured in the culture medium formed on the subject SUB. More specifically, the subject SUB is, for example, a glass Petri dish, but is not limited to this and may have other configurations that function in a similar manner. Furthermore, the culture medium formed on the subject SUB does not exhibit complete light-blocking properties, but rather exhibits a degree of light-transmittance that varies depending on the presence or absence of colonies and the thickness of the colonies.

[0037] 6 is a schematic diagram showing the positional relationship between the main components of the detection device 1 and the detectable object SUB. When the detectable object SUB is placed between the sensor panel 10 and the light source panel 20, the detectable object SUB is placed on a member 60, as shown in FIG. 6, for example. The member 60 functions as a member provided so that the detectable object SUB can be placed between the detection area SA and the light source panel 20.

[0038] In this embodiment, as shown in FIGS. 5 and 6 , the sensor panel 10 is positioned below the detection target SUB, and the light source panel 20 is positioned above the detection target. The member 60 of this embodiment also functions as an optical member that limits the light emitted from the light sources 22 of the light source panel 20 and reaches the sensor panel 10. Specifically, the member 60 has any of a plate-like louver, a cylindrical opening, or a microlens. The plate-like louver is a plurality of parallel-arranged plate-like structures whose plate surfaces are aligned along the third direction Dz. The structures are preferably made of a material with strong light absorption properties. The cylindrical opening is a cylindrical opening that penetrates in the third direction Dz from a base of the member 60 aligned along a plane (Dx-Dy plane) perpendicular to the third direction Dz. The base is preferably made of a material with strong light absorption properties. The microlens is a tiny lens whose optical axis is aligned along the third direction Dz. The base of the member 60 that supports the microlens is preferably made of a material with strong light absorption properties. Regardless of whether the member 60 has a plate-shaped louver, a cylindrical opening, or a microlens, the member 60 as an optical member is provided for the purpose of limiting the direction of travel of light emitted from the light source 22 and reaching the sensor panel 10 to the third direction Dz or a direction with a shallower inclination angle with respect to the third direction Dz.

[0039] In the embodiment, the member 60 functions as a member on which the detectable object SUB can be placed and as an optical member, but the member on which the detectable object SUB can be placed and the optical member may be provided separately. For example, the member on which the detectable object SUB can be placed may be a plate-like member provided with a hole in which the detectable object SUB can be placed. Also, the positions of the light source panel 20 and the sensor panel 10 may be reversed. In that case, the member 60 is disposed, for example, above the detectable object SUB and interposed between the detectable object SUB and the sensor panel 10.

[0040] FIG. 7 is a schematic diagram showing an object illuminated with light from the sensor panel 10 from a planar perspective. A planar perspective refers to a perspective from the front of a plane along which the first direction Dx and the second direction Dy extend. Area THA is an area of ​​one surface of the member 60 facing the detectable object SUB that overlaps with the detectable object SUB. Area SHA is an area of ​​one surface of the member 60 facing the detectable object SUB that does not overlap with the detectable object SUB. Boundary ED is the boundary between area THA and area SHA.

[0041] The light-dark pattern indicating the light intensity detected by the multiple optical sensors WA arranged two-dimensionally along the Dx-Dy plane indicates the degree of light transmission through the regions THA and SHA within the detection area SA. If the output corresponding to the light intensity detected by one optical sensor WA is considered to be the grayscale value of one pixel, the combination of the outputs of the multiple optical sensors WA arranged in the detection area SA can be considered a two-dimensional image formed by a combination of multiple pixels. In the following description, unless otherwise specified, the term "image" refers to a two-dimensional image generated by the control circuit 30 combining the outputs of the multiple optical sensors WA arranged in the detection area SA. Furthermore, the term "scanning process" refers to the process in which the control circuit 30 operates the light source 22 of the light source panel 20 to generate light toward the sensor panel 10, and the control circuit 30 acquires the outputs of the sensor panel 10 corresponding to the light intensity detected by the multiple optical sensors WA arranged in the detection area SA to generate an image.

[0042] The configuration that is the premise for detecting light by the multiple optical sensors WA provided in the detection area SA has been described above with reference to Figures 1 to 7. Below, a method for detecting colonies using images will be described with reference to Figures 8 to 14.

[0043] FIG. 8 is a schematic diagram showing an overview of a colony detection method. The "first image" in FIG. 8 is an image before the colony grows. The "second image" in FIG. 8 is an image after the colony grows. An image 150 illustrated as the "first image" in FIG. 8 includes a boundary portion 151, an outside of the medium 152, and an inside of the medium 153. An image 160 illustrated as the "second image" in FIG. 8 includes the boundary portion 151, an outside of the medium 152, and an inside of the medium 163. The inside of the medium 163 includes dark portions 164, 165, and 166. Colony growth occurs when the colony-forming substance (such as a microorganism) is sufficiently cultivated in the medium.

[0044] The boundary area 151 is a portion of the image 160 where a dark area generated corresponding to the boundary ED appears as light and shade (shades of light). Specifically, the boundary area 151 is formed by an output corresponding to the intensity of light detected by an optical sensor WA arranged to overlap the boundary between the area SHA and the area THA from a planar viewpoint. The outside of the medium 152 is a portion of the image 160 where the intensity of light passing through the area SHA appears as light and shade (shades of light). Specifically, the outside of the medium 152 is formed by an output corresponding to the intensity of light detected by an optical sensor WA arranged to overlap the area SHA from a planar viewpoint.

[0045] The medium interior 153 and the medium interior 163 are portions of the image 160 where the intensity of light passing through the region THA appears as light and dark (light and shade). Specifically, the medium interior 153 is formed by an output corresponding to the intensity of light detected by the optical sensor WA, which is positioned to overlap the region THA from a planar perspective. The medium interior 153 reflects the intensity of light passing through the region THA before colonies grow. The medium interior 163 reflects the intensity of light passing through the region THA after colonies grow. The medium interior 163 includes dark areas 164, 165, and 166 resulting from colony growth, while the medium interior 153 does not include such dark areas 164, 165, and 166. In other words, the emergence and growth of colonies causes a decrease in the degree of light detection in the areas where the colonies emerge and grow. In other words, the dark areas 164, 165, and 166 each result from the growth of colonies within the detection object SUB, which overlaps the region THA from a planar perspective. When the light transmittance of the medium itself provided in the detection object SUB is used as a reference, the light transmittance of the area where the colony has grown is relatively low. For this reason, dark areas 164, 165, and 166 appear in image 160 as relatively dark areas compared to the medium interior 163. The light intensity detected in the medium interior 153 reflects the light transmittance of the medium formed in the detection object SUB and the light transmittance of the light-transmitting material that forms the detection object SUB. The light intensity of the medium interior 163 other than the dark areas 164, 165, and 166 is also the same as that of the medium interior 153.

[0046] Note that boundary portion 151 and outside medium 152 are common to image 150 and image 160. This is because the appearance of relatively dark areas such as dark areas 164, 165, and 166 due to colony growth is limited to an area corresponding to the inside of region THA in detection object SUB where colonies can grow. Because boundary portion 151 and outside medium 152 do not overlap with the inside of region THA, they are formed in image 150 and image 160 by output corresponding to substantially the same light intensity, regardless of whether the colony has grown or not.

[0047] The "difference" in FIG. 8 is the difference between the "first image" and the "second image." The difference image 170 illustrated as the "difference" in FIG. 8 includes difference regions 174, 175, and 176. The difference region 174 corresponds to the dark area 164 in the image 160. The difference region 175 corresponds to the dark area 165 in the image 160. The difference region 176 corresponds to the dark area 166 in the image 160. The boundary region 151 and the outside of the medium 152 are common to the image 150 and the image 160.

[0048] The interior 153 of the medium in image 150 does not include dark areas 164, 165, and 166. On the other hand, the interior 153 of the medium in image 160 includes dark areas 164, 165, and 166. Therefore, in a difference image 170, which is the "difference" between image 150 as the "first image" and image 160 as the "second image" shown in FIG. 8, difference regions 174, 175, and 176 appear, which correspond to the dark areas 164, 165, and 166, which are the differences between the interior 153 of the medium and the interior 163 of the medium. When the range of difference regions such as difference regions 174, 175, and 176 appearing in the "difference" such as difference image 170 exceeds a predetermined value, the control circuit 30 determines that a colony has grown sufficiently in the medium of the subject SUB.

[0049] In this embodiment, immediately after the object to be detected SUB is placed on the detection device 1 (see FIG. 5), a scanning process is performed to obtain an image (e.g., image 150) as an initial image, as shown in "First Image" in FIG. 8. Thereafter, the scanning process is performed again every time a predetermined waiting time has elapsed. After the predetermined waiting time has elapsed one or more times, the control circuit 30 performs a process to obtain the difference between the image obtained by the latest scanning process and the initial image. This results in a difference (e.g., difference image 170) as shown in "Difference" in FIG. 8. Therefore, if the image obtained by the latest scanning process is an image (e.g., image 160) as shown in "Second Image," the difference image 170 is obtained as the difference.

[0050] The predetermined waiting time is, for example, 5 minutes, but is not limited to this and can be changed as appropriate. It is desirable to set the predetermined waiting time appropriately according to various conditions, such as the growth rate of the colony, which is assumed based on the environmental conditions in the incubator 120 in which the detection device 1 in which the object to be detected SUB is installed is placed. Hereinafter, the term "comparison process" refers to the process of obtaining the difference between the image obtained in the latest scanning process and the initial image.

[0051] In this way, after the detection object SUB is placed, the control circuit 30 operates the light source 22 to emit light toward the sensor panel 10, and performs an acquisition process to acquire an output from the sensor panel 10 corresponding to the intensity of the light detected by the multiple optical sensors WA. The first of these acquisition processes is an acquisition process for obtaining an initial image. Of these acquisition processes, acquisition processes performed after the first acquisition process are acquisition processes for obtaining the "image obtained by the latest scan process." The acquisition processes performed after the first acquisition process are repeated every predetermined waiting time.

[0052] The comparison process can be said to be a process of comparing a first output, which is the output of the sensor panel 10 obtained in the first acquisition process, with a second output, which is the output of the sensor panel 10 obtained in the most recent acquisition process. Here, the initial image corresponds to the first output. The image obtained in the most recent scanning process corresponds to the second output.

[0053] The appearance of dark areas relative to the culture medium interior 153 and the culture medium interior 163, such as dark areas 164, 165, and 166, is not limited to colony growth. For example, such dark areas can also appear due to foreign matter, such as dust, unintentionally mixed into the detectable object SUB. Hereinafter, unless otherwise specified, the term "foreign matter" refers to foreign matter, such as dust, that is already mixed into the detectable object SUB at the time the detectable object SUB is placed on the detection device 1. Dark areas caused by foreign matter appear from the initial image, i.e., the "first image" in FIG. 8 . Therefore, even if a foreign matter is mixed into the detectable object SUB, unless the foreign matter moves within the detectable object SUB, it will not appear as a difference between the "first image" and the "second image" in the "difference" such as the difference image 170. In other words, if a foreign matter moves within the detectable object SUB, the foreign matter will cause a difference between the "first image" and the "second image" in the "difference."

[0054] In this embodiment, a process for determining whether the range of a differential region, such as differential regions 174, 175, and 176 in differential image 170, has exceeded a predetermined size is performed based on the ratio of the number of pixels constituting the differential region to the total number of pixels constituting the image. In a comparison process performed prior to this determination process, the initial image and the image obtained by the most recent scan are compared pixel by pixel. As a result, pixels with different gradation values ​​(light intensity detected by optical sensor WA) are treated as pixels in the differential region. Therefore, when a foreign object moves within the detection object SUB, both pixels corresponding to the output of optical sensor WA that overlap the position of the foreign object before movement from a two-dimensional viewpoint and pixels corresponding to the output of optical sensor WA that overlap the position of the foreign object after movement from a two-dimensional viewpoint form a differential region. Such a differential region due to a foreign object can cause an erroneous determination in a determination process aimed at detecting colony growth.

[0055] Therefore, in the embodiment, a mechanism is provided for distinguishing between a differential region due to a foreign substance and a differential region due to colony growth. Therefore, in the embodiment, even if a foreign substance that has entered the detection object SUB moves within the detection object SUB, it is possible to prevent the differential region due to the foreign substance from being mistaken for colony growth. Hereinafter, such a mechanism will be described with reference to FIGS. 9 to 14.

[0056] FIG. 9 is a schematic diagram showing the basic mechanism for distinguishing between difference regions due to foreign matter and difference regions due to colony growth. FIG. 9 shows 3×3 pixels out of the q×r pixels included in the image. The pixel located at the center of the 3×3 pixels is assigned coordinates (x, y) = (h, v). The coordinates of pixels included in the region (first unit region) consisting of the 3×3 pixels are shown as a combination of (h-1), h, (h+1) in the x direction and (v-1), v, (v+1) in the y direction. The x direction in the image corresponds to the arrangement of the optical sensors WA in the first direction Dx in the detection region SA. The y direction in the image corresponds to the arrangement of the optical sensors WA in the second direction Dy in the detection region SA.

[0057] "Example 1" in FIG. 9 shows a first unit area included in an initial image and the positions of foreign objects 531, 532, and 533 within that first unit area. "Example 2" in FIG. 9 shows a first unit area included in an image obtained by a scan process subsequent to the scan process that acquires the initial image and the positions of foreign objects 531, 532, and 533 within that first unit area. The positions of foreign objects 531, 532, and 533 are different between "Example 1" and "Example 2." In particular, in "Example 1," foreign object 531 is positioned so as to overlap with pixel (x, y) = (h, v), whereas in "Example 2," foreign object 531 is positioned so as to overlap with pixel (x, y) = (h-1, v).

[0058] As described above, in the comparison process, the initial image and the image obtained by the latest scan process are compared pixel by pixel, and the pixels with different gradation values ​​(light intensity detected by the optical sensor WA) are treated as pixels in the difference region. More specifically, I satisfying the following formula (1) d The pixel corresponding to (x, y) is treated as a pixel in the difference domain. I d (x,y)=|I(x,y)-I b (x,y)|(1)

[0059] I(x, y) in equation (1) is the gradation value of the pixel of the image obtained in the latest scan process. b (x, y) is the gradation value of the pixel of the initial image. Therefore, I in Equation (1) d (x, y) is the absolute value of the difference between the gradation value of the pixel of the image obtained by the latest scan process and the gradation value of the pixel of the initial image. b (x,y),I d The coordinates of the target pixel for each (x, y) are common and are managed by the value of (x, y). For example, in the comparison process of the pixel (x, y) = (h, v), I(x, y), I b (x,y),I d For each (x,y), (x,y)=(h,v) is substituted.

[0060] In an embodiment, I d Pixels where (x,y) is not 0 are treated as pixels in the difference region. Therefore, the pixels where (x,y)=(h,v) and (x,y)=(h-1,v) shown in FIG. 9 are treated as pixels in the difference region when the image of "Example 2" is obtained. However, the reason why the pixels where (x,y)=(h,v) and (x,y)=(h-1,v) are treated as pixels in the difference region is due to the movement of foreign substance 531. In addition, since the position of foreign substance 533 also changes between "Example 1" and "Example 2," there is a possibility that the pixels where (x,y)=(h+1,v), (x,y)=(h,v+1), and (x,y)=(h+1,v+1) may also be treated as pixels in the difference region. In this way, I calculated by equation (1) d With difference region pixels based only on (x, y) values, it is difficult to suppress the appearance of difference region pixels due to changes in the positions of foreign objects such as foreign objects 531 and 533.

[0061] Therefore, in the embodiment, a filter process is performed. In the filter process performed in the embodiment, a process is performed to obtain a comprehensive difference between a plurality of pixels included in a predetermined filter process unit area. More specifically, I that satisfies the following formula (2) is performed. D The pixel corresponding to (x, y) is treated as a pixel in the difference domain.

number

[0062] I(x+m,y+n) in equation (2) is the gradation value of the pixel of the image obtained in the latest scan process. b (x+m, y+n) is the gradation value of the pixel of the initial image. Here, m is a variable that takes an integer value in the range from -M to M. Also, n is a variable that takes an integer value in the range from -N to N. Here, in the example of FIG. 9, M=N=1. Therefore, I in equation (2) D (x,y) is the absolute value of the difference between the sum of the gradation values ​​of 3x3 pixels of the image obtained by the latest scan process, with coordinates of x and y ±1, centered at (x,y)=(h,v), and the sum of the gradation values ​​of 3x3 pixels of the initial image, with coordinates of x and y ±1, centered at (x,y)=(h,v).

[0063] In the example shown in FIG. 9, when viewed from the area 301 consisting of only pixels (x, y) = (h, v), there is a difference between the area 301 of the "first example" and the area 301 of the "second example" due to the presence or absence of the foreign substance 531. Therefore, I obtained by the formula (1) d (x, y) is not 0. On the other hand, when viewed in a 3×3 pixel area 302 with coordinates of ±1 in x and y centered at (x, y) = (h, v), the area 302 of the "first example" and the area 302 of the "second example" are common in that they contain foreign objects 531, 532, and 533. Therefore, I obtained by equation (2) D (x,y) becomes 0.

[0064] Here, it is assumed that a dark area due to the growth of a colony at the time of "Example 2" has appeared in the region 301 separately from the foreign objects 531, 532, and 533. This dark area is a new dark area that did not appear in "Example 1". Therefore, the difference due to this dark area is calculated by the formula (2) I D (x, y). In other words, if a dark area appears due to the growth of the colony, I D (x,y) cannot be 0.

[0065] In an embodiment, I obtained by formula (1) d (x, y) and I obtained from equation (2) D If both (x, y) are equal to or greater than the predetermined threshold Th, the pixel (x, y) = (h, v) is treated as a pixel in the difference region. In other words, in this case, it is considered that a dark area due to colony growth has appeared in the pixel (x, y) = (h, v). On the other hand, I obtained by Equation (1) d (x, y) and I obtained from equation (2) D If at least one of (x, y) is less than the threshold value Th, the pixel at (x, y) = (h, v) is not treated as a pixel in the difference region. That is, in this case, no dark area appears in the pixel at (x, y) = (h, v), or even if a dark area appears, it is considered to be due to the movement of a foreign object. The threshold value Th is a value greater than 0, and is desirably set appropriately in order to better distinguish between dark areas due to foreign objects and dark areas due to colony growth. As an example, the threshold value Th is 10.

[0066] Formula (1)I d (x, y) and I in equation (2) D The process of obtaining (x, y) is performed individually for each pixel included in the image. In this way, the comparison process includes a first comparison process and a second comparison process. The first comparison process is a process of comparing the first output (initial image) with the second output (image obtained in the latest scan process) for each output from each of the multiple optical sensors WA. In equation (1), I d The process of calculating (x, y) corresponds to the first comparison process. The second comparison process is a process of comparing the first output and the second output in units of outputs from a region including one optical sensor WA and other optical sensors WA arranged around the one optical sensor WA (for example, region 302 and region 303 described later). In equation (2), I D The process of calculating (x, y) corresponds to the second comparison process.

[0067] The control circuit 30 determines that the output of the optical sensor WA that satisfies the first and second conditions is the output of the optical sensor WA that detected the light of the area where the dark area occurs due to overlap with the colony. The first condition is determined by the first comparison process described above, that is, by the equation (1) when I d In the process of calculating (x, y), there is a difference of a predetermined value or more between the first output (initial image) and the second output (image obtained in the latest scan process). The second condition is that when the optical sensor WA that satisfies the first condition is a certain optical sensor WA (the optical sensor WA that generated the output that becomes the basis for the pixel of (x, y) = (h, v)), the second comparison process, i.e., I in equation (2), D In the process of calculating (x, y), there is a difference of a predetermined value or more between the first output (initial image) and the second output (image obtained in the most recent scan process). The difference of a predetermined value or more means, for example, a difference of a threshold value Th or more.

[0068] In the example shown in Figure 9, I D Although the values ​​of M and N when calculating (x, y) are M=N=1, the values ​​of M and N are not limited to this. For example, the values ​​of M and N can be changed and calculated multiple times. D (x, y) may be calculated.

[0069] Figure 10 is a schematic diagram showing a more advanced mechanism for distinguishing between difference regions due to foreign matter and difference regions due to colony growth. Figure 10 shows 5x5 pixels out of the qxr pixels included in the image. The pixel located at the center of the 5x5 pixels is assigned coordinates (x,y) = (h,v). The coordinates of the pixels included in the region (second unit region) consisting of the 5x5 pixels are shown as a combination of (h-2), (h-1), j, (h+1), (h+2) in the x direction and (v-2), (v-1), v, (v+1), (v+2) in the y direction.

[0070] 10 also shows a 3×3 pixel region 302 with x and y coordinates of ±1 centered around the pixel (x,y)=(h,v), and a 5×5 pixel region 303 with x and y coordinates of ±2 centered around the pixel (x,y)=(h,v). The "Third Example" in FIG. 10 shows a second unit region included in the initial image and the positions of foreign particles 531, 532, and 533 within the second unit region. The "Fourth Example" in FIG. 9 shows a second unit region included in an image obtained by a scanning process subsequent to the scanning process for acquiring the initial image, and the positions of foreign particles 531, 532, and 533 within the second unit region.

[0071] In the "third example" of FIG. 10, some of the foreign objects 532 and 533 are inside the region 302, and other parts are outside the region 302. On the other hand, in the "fourth example," the entire foreign objects 532 and 533 are inside the region 302. Here, in equation (2), I D When the values ​​of M and N are M=N=1 when calculating (x, y), D The 3x3 pixels (x, y) that are the targets for calculating the difference in pixel gradation values ​​are the pixels that make up region 302. The difference in gradation values ​​occurs between region 302 in the "third example" and region 302 in the "fourth example" due to the difference in the proportion of foreign matter 532, 533 within region 302. Therefore, when the values ​​of M and N are M=N=1, I obtained by equation (2) D (x,y) cannot be 0.

[0072] On the other hand, in equation (2), I D When the values ​​of M and N are calculated as (x, y), M=N=2. Related I D The 5x5 pixels for which the difference in pixel gradation value is calculated in (x, y) are the pixels that make up region 303. Region 303 in "Example 3" and region 303 in "Example 4" are common in that they contain foreign objects 531, 532, and 533. Therefore, when the values ​​of M and N are M=N=2, I obtained by equation (2) D (x,y) becomes 0.

[0073] As shown in the examples referring to "Example 3" and "Example 4" in Figure 10, I DBy calculating (x, y), it is possible to more accurately suppress the appearance of a difference region due to the movement of a foreign object. D In the process of calculating (x, y), the first output (initial image) and the second output (image obtained in the latest scan process) may be compared in units of outputs from a first region (e.g., region 302) and a second region (e.g., region 303) that have different numbers of optical sensors WA arranged around a certain optical sensor WA (the optical sensor WA that generated the output that became the basis for the pixel (x, y) = (h, v)). Here, the second condition described above may be satisfied when there is a difference between the first output and the second output in both the first region and the second region that is equal to or greater than a predetermined value, and the second condition described above may not be satisfied when there is no difference between the first output and the second output in at least one of the first region and the second region that is equal to or greater than a predetermined value.

[0074] In addition, I according to equation (2) D When calculating (x, y), the pixels included in the first unit area and the second unit area may be individually weighted, or may not be individually weighted. D This means that all of the multiple pixels that are the targets of difference calculation when calculating (x, y) are treated equally.

[0075] Fig. 11 is a diagram showing weighting coefficients for the first unit area and the second unit area when all of the pixels are treated equally. The "3x3" averaging filter shown in Fig. 11 indicates that the weighting coefficients applied to each of the 3x3 pixels included in the first unit area are all the same, "1 / 9". When the "3x3" averaging filter shown in Fig. 11 is applied, the weighting coefficients I according to equation (2) are calculated with M=N=1. D When calculating (x, y), the entire right side is multiplied by 1 / 9. This is the I DThis is the same as multiplying (x, y) by 1 / 9. The "5x5" averaging filter shown in Figure 12 indicates that the weighting coefficients applied to each of the 5x5 pixels included in the second unit area are all the same, at "1 / 25." When the "5x5" averaging filter shown in Figure 11 is applied, the weighting coefficients I according to equation (2) are calculated with M=N=2. D When calculating (x, y), the entire right side is multiplied by 1 / 25. This is the I D This is the same as multiplying (x,y) by 1 / 25.

[0076] According to the weighting coefficients shown in Figure 11, I D Although the relative relationship with the threshold Th may change due to the application of a magnification factor according to a common weighting coefficient to the (x, y) value, I is determined by the position of the pixel in the unit area determined by the values ​​of M and N. D The magnitude of the influence on the (x, y) values ​​is not different. The term "unit area" here refers to the first and second unit areas described above. The same applies hereinafter when simply referring to "unit area."

[0077] Fig. 12 is a diagram showing an example of weighting coefficients when weighting a plurality of pixels included in a first unit area and a second unit area individually. The "3x3" Gaussian filter shown in Fig. 12 indicates that, among the 3x3 pixels included in the first unit area, "4 / 16" is applied to the pixel located at (x,y)=(h,v), "2 / 16" is applied to the pixels located at (x,y)=(h±1,v) and (x,y)=(h,v±1), and "1 / 16" is applied to the pixel located at (x,y)=(h±1,v±1). When the "3x3" Gaussian filter shown in Fig. 12 is applied, I according to equation (2) performed under the condition that M=N=1 is applied. DWhen calculating (x, y), if 0 is substituted for m and n in equation (2), the entire right-hand side is multiplied by 4 / 16. Also, in this case, if 0 is substituted for one of m or n in equation (2) and ±1 is substituted for the other, the entire right-hand side is multiplied by 2 / 16. Also, in this case, if ±1 is substituted for m and n in equation (2), the entire right-hand side is multiplied by 1 / 16.

[0078] In the "5x5" Gaussian filter shown in FIG. 12, of the 5x5 pixels included in the second unit area, "36 / 256" is applied to the pixel located at (x,y)=(h,v), "24 / 256" is applied to the pixels located at (x,y)=(h±1,v) and (x,y)=(h,v±1), and "16 / 256" is applied to the pixel located at (x,y)=(h±1,v±1). It shows that "6 / 256" is applied to the pixels located at (x,y)=(h,v±2) and (x,y)=(h±2,v), "4 / 256" is applied to the pixels located at (x,y)=(h±1,v±2) and (x,y)=(h±2,v±1), and "1 / 256" is applied to the pixels located at (x,y)=(h±2,v±2) and (x,y)=(h±2,v±2). When the "5x5" Gaussian filter shown in Figure 12 is applied, I according to equation (2) performed with M=N=2 is applied. D When calculating (x,y), When 0 is substituted for m and n in equation (2), the entire right-hand side is multiplied by 36 / 256. Also, in this case, when 0 is substituted for one of m or n in equation (2) and ±1 is substituted for the other, the entire right-hand side is multiplied by 24 / 256. Also, in this case, when ±1 is substituted for m and n in equation (2), the entire right-hand side is multiplied by 16 / 256. In this case, when 0 is substituted for either m or n in equation (2) and ±2 is substituted for the other, the entire right-hand side is multiplied by 6 / 256. In this case, when ±1 is substituted for either m or n in equation (2) and ±2 is substituted for the other, the entire right-hand side is multiplied by 4 / 256. In this case, when ±2 is substituted for m and n in equation (2), the entire right-hand side is multiplied by 1 / 256.

[0079] According to the weighting coefficients shown in FIG. 12, I is determined by the position of the pixel in the unit area determined according to the values ​​of M and N. D The magnitude of the influence on the (x, y) value is different. Specifically, the difference in the gradation value of the pixel located closer to the center of the unit area is I D In other words, the difference in the gradation values ​​of pixels located farther from the center of the unit area is I D The effect on the value of (x, y) is smaller. Therefore, for example, assume that there is a foreign object within the unit area, and that the position of the foreign object in the initial image is farther away from (x, y) = (h, v), i.e., that it is at a position overlapping with a pixel near the edge of the unit area. Furthermore, in this case, assume that the foreign object that overlapped with a pixel near the edge of the unit area in the initial image has moved outside the unit area in the latest image. Here, the Gaussian filter described above is D The degree of influence on the value of (x, y) is smaller than the degree of influence of changes in the gradation values ​​of pixels near the edge of the unit area compared to (x, y) = (h, v) at the center of the unit area. Therefore, at this time, the Gaussian filter works to reduce the influence of I due to the movement of foreign matter. D The degree of change in the (x, y) values ​​is made smaller than with the averaging filter. On the other hand, suppose there is a foreign object within the unit area, and the position of the foreign object in the initial image is closer to (x, y) = (h, v). Furthermore, in this case, suppose that the foreign object has moved outside the unit area in the latest image. In this case, the Gaussian filter reduces the I due to the movement of the foreign object. D The degree of change in the (x, y) values ​​is increased compared to the averaging filter.

[0080] In this way, weighting corresponding to the Gaussian filter is performed, and I D In other words, for the movement of a foreign object that overlaps with a pixel near the edge of the unit area in the initial image, I DAs described with reference to FIG. 12, the second comparison process, that is, the process of calculating I in equation (2), can reduce the influence on the values ​​of (x, y). D In the process of calculating (x, y), the output of a certain optical sensor WA (pixel (x, y) = (h, v)) and the outputs of other optical sensors WA arranged around the certain optical sensor WA may be individually weighted. Here, FIG. 12 shows that the weighting of the output of the certain optical sensor WA is stronger than the weighting of the outputs of the other optical sensors WA. FIG. 12 also shows that the weighting of the output of one of two optical sensors WA that is included in the other optical sensor WA and that is arranged closer to the certain optical sensor WA in the detection area SA is stronger than the weighting of the output of the other optical sensor WA.

[0081] I obtained from the above-described equation (1) d (x, y) and I obtained from equation (2) D Calculation of (x,y) and I d (x,y),I D In the embodiment, the determination based on (x, y) of "whether to treat the pixel at (x, y) = (h, v) as a pixel in the differential domain" is made by the control circuit 30, but may also be made by the host IC 70.

[0082] Furthermore, the determination regarding colony growth based on the number of pixels treated as a differential region is made by, for example, the host IC 70, but may also be made by the control circuit 30. Specifically, the number of optical sensors WA arranged in the detection region SA of the sensor panel 10 is taken as a reference (100%), and when the percentage of the number of pixels treated as a differential region in the latest image becomes equal to or greater than a predetermined percentage, the determination that a colony has grown sufficiently on the detection object SUB is made by, for example, the host IC 70, but may also be made by the control circuit 30. The predetermined percentage is, for example, 5%, but this is merely an example and is not limited to this, and may be an appropriate percentage depending on the conditions required for the target to be cultured in the colony.

[0083] Below, the process flow when the values ​​of M and N in formula (2) are fixed (see FIG. 9) and when the values ​​of M and N in formula (2) are changed (see FIG. 10) will be described with reference to flowcharts. First, the process flow when the values ​​of M and N in formula (2) are fixed (see FIG. 9) will be described with reference to FIG. 13.

[0084] 13 is a flowchart showing the flow of processing performed by the detection device 1 when the values ​​of M and N in equation (2) are fixed. First, an initial image is acquired (step S1). Specifically, immediately after the object to be detected SUB is placed on the detection device 1 (see FIG. 5), a scanning process is performed to obtain an image (e.g., image 150) as the initial image, such as that shown as "first image" in FIG. 8. The control circuit 30 generates an image from the output of the optical sensor WA obtained by the scanning process and stores it as the initial image.

[0085] Next, the control circuit 30 initializes a timer (step S2). This timer is a timer for counting the waiting time until the scan process is performed again. The timer is managed, for example, by a counter variable and a timing clock, but may also be managed by a dedicated timer circuit included in the control circuit 30. After the process of step S2, the timer counts the elapsed time (step S3). After the process of step S2, the process of step S3 is continued until it is counted that the predetermined waiting time has elapsed through the process of step S3 (step S4; No).

[0086] If the predetermined waiting time has elapsed (step S4; Yes), an image is acquired (step S5). Specifically, the scanning process is performed again. The control circuit 30 generates an image from the output of the optical sensor WA obtained by the scanning process, and sets the image as the latest image.

[0087] After the process of step S5, one unprocessed pixel is selected from the pixels of the latest image obtained by the process of step S5 (step S6). The unprocessed pixel here refers to a pixel that has not yet been subjected to the processes of steps S7 to S9, which will be described later.

[0088] The control circuit 30 sets the coordinates of the pixel selected in the process of step S6 as (x, y) = (h, v), and calculates I in the above equation (1). d (x, y) is calculated (step S7). d It can be said that (x, y) is a difference value to which no filter is applied as described with reference to Figures 13 and 14. Furthermore, the control circuit 30 sets the coordinates of the pixel selected in the process of step S6 as (x, y) = (h, v) and calculates I in the above-mentioned equation (2). D (x, y) is calculated (step S8). d It can be said that (x, y) is a value of the difference (filtered difference) to which a filter such as that described with reference to Figures 13 and 14 has been applied. In other words, in the process of step S8, weighting corresponding to a Gaussian filter such as that in Figure 14 may be performed, or weighting corresponding to an averaging filter such as that in Figure 13 may be performed. D In the process of step S7 and the process of step S8, an absolute value indicating the difference between a pixel of the initial image obtained in the process of step S1 and a pixel of the latest image obtained in the process of step S5 is calculated.

[0089] After the processing of step S7 and the processing of step S8, the control circuit 30 d (x, y) and I obtained in the processing of step S8 D It is determined whether both (x, y) are equal to or greater than the threshold value Th (step S9). d (x,y) and I DIf it is determined that both (x, y) are equal to or greater than the threshold value Th (step S9; Yes), the control circuit 30 treats the pixel selected in the processing of step S6 as a pixel in the differential region (step S10). That is, in this case, it is considered that a dark area due to colony growth has appeared in the pixel selected in the processing of step S6. After processing step S9, the control circuit 30 determines whether there are any unprocessed pixels among the pixels of the latest image obtained in the processing of step S5 (step S11). Here, if it is determined that there are unprocessed pixels (step S11; No), the control circuit 30 proceeds to the processing of step S6.

[0090] On the other hand, if it is determined in step S11 that there are no unprocessed pixels (step S11; Yes), the host IC 70 determines whether the percentage of pixels treated as differential regions in the latest image is equal to or greater than a predetermined percentage, with the number of optical sensors WA arranged on the sensor panel 10 set as the reference (100%) (step S12). If it is determined that the percentage of pixels treated as differential regions is equal to or greater than the predetermined percentage (step S12; Yes), a proliferation detection process is performed (step S13). Specifically, the host IC 70 sends an electronic message to a pre-registered address as the contact information for the administrator of the detection system 100 to notify the administrator that the colony has sufficiently expanded on the detection target SUB. The electronic message may be, for example, an email, but is not limited to this and may be another form of message or audio signal that functions similarly. On the other hand, if it is determined in step S11 that the percentage of pixels treated as differential regions is less than the predetermined percentage (step S12; No), the process proceeds to step S2. That is, the latest images are continuously acquired at predetermined waiting times until the colony has sufficiently expanded on the detection object SUB.

[0091] In the process of step S9, I d (x,y) and I DIf it is determined that at least one of (x, y) is less than the threshold value Th (step S9; No), the process proceeds to step S11. That is, in this case, it is determined that no dark area has appeared in the pixel selected in the process of step S6, or even if a dark area has appeared, it is determined that this is due to the movement of a foreign object.

[0092] Next, the processing flow when the values ​​of M and N in formula (2) are changed (see FIG. 10) will be described with reference to FIG. 14. In the description of the processing flow with reference to FIG. 14, the same steps as those described with reference to FIG. 13 will be assigned the same step numbers and descriptions thereof will be omitted.

[0093] Fig. 14 is a flowchart showing the flow of processing performed by the detection device 1 when the values ​​of M and N in formula (2) are changed. Of the processing shown in Fig. 14 that is performed by the detection device 1 when the values ​​of M and N in formula (2) are changed, the flow of processing from step S1 to step S8 is the same as when the values ​​of M and N in formula (2) are fixed (see Fig. 13).

[0094] In the process performed by the detection device 1 when the values ​​of M and N in the formula (2) are changed, I d (x,y) and I D If it is determined that both (x, y) are equal to or greater than the threshold value Th (step S9; Yes), the control circuit 30 expands the filter processing unit area (step S14). Specifically, at least one of the values ​​of M and N is changed to a larger value. The processing of step S15, which is performed after the processing of step S14, is the same as the processing of step S8, but at least one of the values ​​of M and N is made larger than that in the processing of step S8. In the embodiment, M=N=1 is applied in the processing of step S8, and M=N=2 is applied in the processing of step S15, but these are just examples.

[0095] After the process of step S15, I obtained in the process of step S7 d (x, y) and I obtained in the processing of step S15 DIt is determined whether both (x, y) are equal to or greater than the threshold value Th (step S16). d (x,y) and I D If it is determined that both of (x, y) are equal to or greater than the threshold value Th (step S16; Yes), the process proceeds to step S10. d (x,y) and I D If it is determined that at least one of (x, y) is less than the threshold value Th (step S16; No), the process proceeds to step S11. Except for the points specifically mentioned above, the process flow with reference to Fig. 14 is the same as the process flow with reference to Fig. 13.

[0096] Hereinafter, with reference to FIG. 15, an example of a configuration common to the above-described embodiment and various modified examples will be described. FIG. 15 is a schematic diagram showing an example of the configuration of the light source 22. As shown in FIG. 15, 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 are light-emitting elements (e.g., LDs) that emit light of different colors. In the 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.

[0097] In this embodiment, the first light source 22R, the second light source 22G, and the third light source 22B are individually controlled to emit light. That is, when any one of the first light source 22R, the second light source 22G, and the third light source 22B is turned on, the other two are not turned on. In the colony detection described with reference to FIGS. 8 to 14, detection with the first light source 22R turned on (first light detection), detection with the second light source 22G turned on (second light detection), and detection with the third light source 22B turned on (third light detection) are individually performed. Then, if it is determined that the colony has been sufficiently cultivated in at least one of the first light detection, the second light detection, and the third light detection, the above-described growth detection process is performed. Note that the first light source 22R, the second light source 22G, and the third light source 22B may be turned on simultaneously to irradiate white light. That is, colony detection may be performed under conditions where white light is irradiated.

[0098] As described above, according to the embodiment, the detection device 1 includes a sensor panel (e.g., sensor panel 10) having a detection area SA in which a plurality of optical sensors (e.g., optical sensors WA) are two-dimensionally arranged; a light source (e.g., light source 22) that emits light; a member (e.g., member 60) that is provided so that a detection target (e.g., detection target SUB) can be placed between the detection area SA and the light source; and a control circuit (e.g., control circuit 30) that controls the operation of the sensor panel and the light source and performs processing based on the outputs of the plurality of optical sensors. A culture medium capable of cultivating colonies is provided on the detection target. After the detection target is placed, the control circuit operates the light source to generate light toward the sensor panel and performs an acquisition process to acquire an output of the sensor panel corresponding to the intensity of the light detected by the plurality of optical sensors. The acquisition process is repeated every predetermined waiting time, and a comparison process is performed to compare a first output (e.g., an initial image) that is the output of the sensor panel obtained in the initial acquisition process with a second output (e.g., an image obtained in the most recent scan process) that is the output of the sensor panel obtained in the most recent acquisition process. The comparison process is a first comparison process (for example, I in Equation (1)) that compares the first output with the second output in units of outputs from each of the plurality of optical sensors. d a process of calculating (x, y)), and a second comparison process of comparing the first output and the second output in units of outputs from an area including one optical sensor and other optical sensors arranged around the one optical sensor (for example, I in Equation (2)). DThe control circuit determines that the output of an optical sensor that satisfies a first condition and a second condition is the output of an optical sensor that overlaps a colony. The first condition is that there is a difference of a predetermined value or more between the first output and the second output in the first comparison process. The second condition is that when an optical sensor that has a difference of a predetermined value or more between its first output and its second output in the first comparison process is determined to be the optical sensor, there is a difference of a predetermined value or more between its first output and its second output in the second comparison process. This makes it possible to distinguish between the movement of foreign matter (e.g., foreign matter 531, 532, 533) and an increase in dark areas due to colony cultivation. Therefore, a decrease in the accuracy of sensing the progress of colony cultivation due to confusion between the two can be further suppressed.

[0099] In addition, in the second comparison process, a first output (e.g., an initial image) is compared with a second output (e.g., an image obtained in the latest scan process) in units of outputs from an area including a certain optical sensor (e.g., optical sensor WA) and other optical sensors arranged around the certain optical sensor. The first output is compared with the second output in units of outputs from each of a first area (e.g., area 302) and a second area (e.g., area 303) having a different number of optical sensors that are considered to be the other optical sensors. The second condition is satisfied when there is a difference between the first output and the second output that is equal to or greater than a predetermined value in both the first area and the second area, and the second condition is not satisfied when there is no difference between the first output and the second output that is equal to or greater than a predetermined value in at least one of the first area and the second area. This makes it possible to more accurately distinguish between the movement of foreign matter (e.g., foreign matter 531, 532, 533) and an increase in dark areas due to colony cultivation. Therefore, it is possible to more reliably prevent a decrease in the accuracy of sensing the progress of colony cultivation due to these confusions.

[0100] Furthermore, in a second comparison process that compares a first output (e.g., an initial image) with a second output (e.g., an image obtained in the latest scan process) in units of outputs from an area including a certain optical sensor (e.g., optical sensor WA) and other optical sensors arranged around the certain optical sensor, weighting is individually assigned to each of the outputs of the certain optical sensor and the other optical sensors, so that it is possible to arbitrarily set which part of the output of an area including a certain optical sensor (optical sensor WA) and other optical sensors arranged around the certain optical sensor in which emphasis is placed on the movement of foreign objects (e.g., foreign objects 531, 532, 533).

[0101] In addition, in the weighting, the weighting for the output (for example, pixel (x, y) = (h, v)) of a certain optical sensor (for example, optical sensor WA) is stronger than the weighting for the output of other optical sensors, and the weighting for the output of one of two optical sensors that is included in the other optical sensor and is arranged closer to the certain optical sensor among two adjacent optical sensors in the detection area SA is stronger than the weighting for the output of the other sensor. As a result, with regard to the movement of a foreign object (for example, foreign objects 531, 532, 533) that overlaps with the vicinity of the edge of the output of the area that includes the certain optical sensor (optical sensor WA) and the other optical sensors arranged around the certain optical sensor in the first output (for example, initial image), the second comparison process (for example, I D This can reduce the impact on the process of calculating (x, y).

[0102] Furthermore, by providing an optical element (e.g., element 60) between a sensor panel (e.g., sensor panel 10) and a detectable object (e.g., detectable object SUB) that limits the light emitted from a light source (e.g., light source 22) and reaching the sensor panel, it becomes easier to limit the light emitted from the light source and reaching the sensor panel to light that is more preferable from the viewpoint of detecting colonies in the detectable object.

[0103] Furthermore, by having an optical element (e.g., element 60) with either a plate-shaped louver, a cylindrical opening, or a microlens, it becomes easier to limit the light emitted from a light source (e.g., light source 22) and reaching a sensor panel (e.g., sensor panel 10) to the opposing direction between the light source and the sensor panel (e.g., third direction Dz).

[0104] Furthermore, by positioning the sensor panel (e.g., sensor panel 10) below the object to be detected (e.g., object to be detected SUB) and the light source (e.g., light source 22) above the object to be detected, it becomes easier to make the optical element and a member (e.g., member 60) that is arranged so that the object to be detected can be placed between the detection area SA and the light source identical in configuration.

[0105] 15 shows a configuration in which the longitudinal directions of the first light source 22R, the second light source 22G, and the third light source 22B are aligned along the second direction Dy and the first light source 22R, the second light source 22G, and the third light source 22B are arranged in this order from one side to the other side in the first direction Dx. However, this is merely an example of the configuration of the light source 22 and is not intended to be limiting. For example, the shapes of the first light source 22R, the second light source 22G, and the third light source 22B in the light source 22 from a planar perspective and the positional relationship between the first light source 22R, the second light source 22G, and the third light source 22B may be changed as appropriate. Furthermore, a single white light source may be provided instead of the first light source 22R, the second light source 22G, and the third light source 22B.

[0106] 3 are not limited to a configuration of a single switching element. For example, at least one of the switching element 81 and the switching element 85 may have a so-called double gate configuration.

[0107] Furthermore, the detection object such as the detection object SUB is not limited to a Petri dish on which a culture medium is formed, but may be in other forms, such as a plate for suspension culture.

[0108] Furthermore, the arrangement of the optical sensors WA is not limited to a matrix along the first direction Dx and the second direction Dy. For example, the optical sensors WA arranged in adjacent sensor rows in the second direction Dy do not have to be aligned in a straight line along the second direction Dy. Specifically, they may be aligned in a staggered pattern. In terms of sharing the reset signal transmission line 5 and the scanning line 6, it is desirable for the arrangement of the multiple optical sensors WA along the first direction Dx to be aligned in a straight line along the first direction Dx. However, this is not essential and can be changed as appropriate within the scope that does not impair the functionality of the optical sensors WA and the detection area SA. The arrangement of the light sources 22 in the light source panel 20 is also not limited to a matrix and can be any arrangement.

[0109] Furthermore, the values ​​of M and N are not limited to 1 or 2. Natural numbers greater than or equal to 3 may be used as the values ​​of M and N. Furthermore, M does not have to be equal to N. In other words, the unit area does not have to be an area in which the number of pixels aligned in the x direction is equal to the number of pixels aligned in the y direction.

[0110] Furthermore, other effects and advantages brought about by the aspects described in this embodiment that are clear from the description in this specification or that can be appropriately thought of by a person skilled in the art are naturally understood to be brought about by the present disclosure. [Explanation of symbols]

[0111] 1. Detection device 10 Sensor Panel 20 Light Source Panel 22 Light source 30 Control circuit 60 parts 82PD SUB Object to be detected WA Light Sensor

Claims

1. a sensor panel having a detection area in which a plurality of optical sensors are two-dimensionally arranged; a light source that emits light; a member provided so that the object to be detected can be placed between the detection area and the light source; a control circuit that controls the operation of the sensor panel and the light source and performs processing based on outputs of the plurality of optical sensors; The test object is provided with a medium capable of culturing colonies, the control circuit operates the light source after the detection object is placed to generate light directed toward the sensor panel, and performs an acquisition process to acquire an output from the sensor panel corresponding to the intensity of the light detected by the plurality of optical sensors; repeating the acquisition process at predetermined waiting times; performing a comparison process of comparing a first output, which is an output of the sensor panel obtained in a first acquisition process, with a second output, which is an output of the sensor panel obtained in a most recent acquisition process; The comparison process includes: a first comparison process for comparing the first output and the second output in units of outputs from each of the plurality of optical sensors; a second comparison process of comparing the first output with the second output in units of outputs from an area including one optical sensor and other optical sensors arranged around the one optical sensor, the control circuit determines that an output of an optical sensor that satisfies a first condition and a second condition is an output of an optical sensor that overlaps with the colony, the first condition is that there is a difference between the first output and the second output equal to or greater than a predetermined value in the first comparison process; the second condition is that when an optical sensor in which a difference between the first output and the second output in the first comparison process is determined to be equal to or greater than a predetermined value is used as the one optical sensor, a difference between the first output and the second output in the second comparison process is equal to or greater than the predetermined value. Detection device.

2. In the second comparison process, the first output and the second output are compared in units of outputs from a first region and a second region having different numbers of optical sensors that are the other optical sensors, The second condition is satisfied when there is a difference between the first output and the second output equal to or greater than the predetermined value in both the first region and the second region, and the second condition is not satisfied when there is no difference between the first output and the second output equal to or greater than the predetermined value in at least one of the first region and the second region. The detection device according to claim 1 .

3. In the second comparison process, the output of the one optical sensor and the output of the other optical sensor are individually weighted.

3. The detection device according to claim 1 or 2.

4. the weighting of the output of the one optical sensor is stronger than the weighting of the output of the other optical sensor; a weighting for an output of one of two adjacent optical sensors included in the other optical sensor and arranged closer to the one optical sensor in the detection area is stronger than a weighting for an output of the other sensor; The detection device according to claim 3 .

5. an optical member is provided between the sensor panel and the object to be detected, the optical member limiting the light emitted from the light source and reaching the sensor panel; 3. The detection device according to claim 1 or 2.

6. The optical member has any one of a plate-shaped louver, a cylindrical opening, and a microlens. The detection device according to claim 5 .

7. the sensor panel is located below the object to be detected, The light source is located above the object to be detected.

3. The detection device according to claim 1 or 2.

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