Image acquisition device

Abstract

To provide an image acquisition device which can obtain a higher detection accuracy.SOLUTION: An image acquisition device includes: a light source; a holding member located above the light source, the holding member holding a container in which an object to be detected is accommodated; a viewing angle control film located above the container; a planar optical sensor located above the viewing angle control film; a transparent adhesive layer located between the viewing angle control film and the optical sensor, the adhesive layer bonding the viewing angle control film and the optical sensor together; and a spring for urging the holding member upward to press the container against the viewing angle control film.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to image acquisition devices. [Background technology]

[0002] Patent Document 1 discloses an image acquisition device that includes an optical sensor (photo sensor), a container containing a detectable substance (microorganism) and a culture medium, and a light source, and acquires images of the growth of microorganisms in the container over time. Specifically, the container is placed above the optical sensor (photo sensor), and the light source is placed above the container. Light emitted from the light source passes through the detectable substance and the culture medium in the container and reaches the optical sensor. The amount of light irradiated onto the photodiode of the optical sensor differs between the area overlapping with the detectable substance and the area not overlapping with the detectable substance, allowing the optical sensor to capture an image of the detectable substance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2018-33430 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for an image acquisition device that can achieve higher detection accuracy.

[0005] An object of the present disclosure is to provide an image acquisition device that can achieve higher detection accuracy. [Means for solving the problem]

[0006] An image acquisition device of one embodiment of the present invention comprises a light source, a holding member located above the light source and holding a container containing a detectable object, a view angle control film located above the container, a planar optical sensor located above the view angle control film, a translucent adhesive layer located between the view angle control film and the optical sensor and bonding the view angle control film to the optical sensor, and an elastic member that pushes the holding member upward and urges it to press the container against the view angle control film. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a cross-sectional view schematically showing an image acquisition device according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram showing an enlarged portion of FIG. [Figure 3] FIG. 3 is an enlarged perspective view of the container of FIG. [Figure 4] FIG. 4 is a block diagram illustrating an example of the configuration of the image acquisition device according to the embodiment. [Figure 5] FIG. 5 is a cross-sectional view schematically showing a collimator layer according to the embodiment. [Figure 6] FIG. 6 is a cross-sectional view schematically showing a louver layer according to the embodiment. [Figure 7A] FIG. 7A is a schematic diagram showing a state in which a view angle control film and an optical sensor according to Comparative Example 1 are attached to a housing. [Figure 7B] FIG. 7B is a schematic diagram showing a state in which the view angle control film and the optical sensor according to Comparative Example 2 are attached to a housing. [Figure 8] FIG. 8 is a schematic diagram of an image acquisition device according to a comparative example. [Figure 9] FIG. 9 is a photographic image of the culture medium captured by the image acquisition device of the embodiment. [Figure 10] FIG. 10 is a photographic image of the culture medium taken with the image acquisition device of Comparative Example 2 shown in FIG. 7B. DETAILED DESCRIPTION OF THE INVENTION

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

[0009] [Embodiment] First, an embodiment will be described. Fig. 1 is a cross-sectional view that schematically shows an image acquisition device according to an embodiment.

[0010] 1, the image acquisition device 100 (detection device 101) includes a housing 3, a light source 7, a holding member 2, a view angle control film 82, an optical sensor 81, a light-transmitting adhesive layer 4, and a spring (elastic member) 5. The holding member 2 holds a container 110.

[0011] The housing 3 includes a top plate 31, side plates 32, and a bottom plate 33. The space surrounded by the top plate 31, side plates 32, and bottom plate 33 accommodates the light source 7, the holding member 2, the view angle control film 82, the optical sensor 81, the light-transmitting adhesive layer 4, the spring (elastic member) 5, and the like.

[0012] The light source 7 includes a light source substrate 72 and a plurality of light-emitting elements 71. The light-emitting elements 71 are configured by, for example, light-emitting diodes (LEDs). The light-emitting elements 71 emit light L. The light L emitted from the light-emitting elements 71 passes through the container 110 and is irradiated toward the optical sensor 81.

[0013] The holding member 2 is located above the light source 7. The holding member 2 holds the container 110. The container 110 is translucent. At least the portion of the holding member 2 that overlaps with the container 110 in the vertical direction is translucent.

[0014] The view angle control film 82 limits the angle of incidence of light L incident on the optical sensor 81 so that the optical sensor 81 can capture a clear image. That is, of the light L emitted from the light emitting element 71, the light that passes through the view angle control film 82 is a component that travels in a direction perpendicular to the optical sensor 81. The view angle control film 82 is located above the container 110 and below the optical sensor 81. The view angle control film 82 is made of a resin such as silicone rubber or polycarbonate, for example. The structure of the view angle control film 82 will be described in detail later.

[0015] The optical sensor 81 is a planar detection device including a plurality of photodiodes 813 (photodetection elements, see FIG. 4) arranged in a plane. The optical sensor 81 is located above the view angle control film 82. Light L that has passed through the view angle control film 82 travels in a direction perpendicular to the optical sensor 81, and this perpendicular light is irradiated toward the photodiodes 813. The amount of light irradiated onto the plurality of photodiodes 813 of the optical sensor 81 differs between the area overlapping with the object to be detected 114 and the area not overlapping with the object to be detected 114. This allows the optical sensor 81 to capture an image of the object to be detected 114.

[0016] The light-transmitting adhesive layer 4 bonds the view angle control film 82 and the optical sensor 81. Specifically, the light-transmitting adhesive layer 4 bonds the entire surface of the view angle control film 82 and the entire surface of the optical sensor 81. In other words, the entire upper surface of the view angle control film 82 is bonded to the lower surface of the light-transmitting adhesive layer 4, and the entire lower surface of the optical sensor 81 is bonded to the upper surface of the light-transmitting adhesive layer 4. The light-transmitting adhesive layer 4 is located between the view angle control film 82 and the optical sensor 81. In other words, a predetermined gap is provided between the optical sensor 81 and the view angle control film 82 in the vertical direction, and the light-transmitting adhesive layer 4 fills this predetermined gap. The light-transmitting adhesive layer 4 is, for example, larger than the container 110 when viewed from above. In other words, the edge of the light-transmitting adhesive layer 4 is located outside the edge of the container 110 when viewed from above. The thickness of the light-transmitting adhesive layer 4 is, for example, 10 μm or more and 500 μm or less. The refractive index of the light-transmitting adhesive layer 4 is, for example, a value between the refractive index of the optical sensor 81 and the refractive index of the view angle control film 82. The refractive index of the light-transmitting adhesive layer 4 is, for example, 1.4 or more and 1.58 or less.

[0017] The spring (elastic member) 5 biases the holding member 2 upward. Since the container 110 is held by the holding member 2, the spring 5 biases the holding member 2 and the container 110 upward. The spring 5 is located between the light source substrate 72 and the holding member 2. The spring 5 may also be located between the bottom plate 33 of the housing 3 and the holding member 2.

[0018] Fig. 2 is a schematic enlarged view of a part of Fig. 1. Fig. 3 is an enlarged perspective view of the container of Fig. 1. As shown in Figs. 2 and 3, the container 110 is, for example, a light-transmitting petri dish.

[0019] The container 110 includes a container body 111 and a cover member 112. The container body 111 has a bottom 111a, a side 111b, and a protrusion 111c. The bottom 111a is a disk-shaped member. The side 111b has a cylindrical shape extending from the outer periphery of the bottom 111a in a direction perpendicular to the bottom 111a. The protrusion 111c has a cylindrical shape extending from the outer periphery of the bottom 111a in a direction perpendicular to the bottom 111a and on the opposite side of the side 111b. As shown in FIG. 1 , a culture medium 113 is contained in the container body 111, and a detectable substance 114 is applied to the surface of the culture medium 113. The detectable substance 114 is, for example, a microorganism such as a bacterium or a sample containing a microorganism, and forms a colony on the culture medium 113 over time.

[0020] The cover member 112 is a lid that covers the opening of the container body 111. The cover member 112 has a top surface 112a and a side surface 112b. The top surface 112a is a disk-shaped member, and the side surface 112b has a cylindrical shape that extends from the outer periphery of the top surface 112a in a direction perpendicular to the top surface 112a.

[0021] As described above, the spring 5 pushes the holding member 2 and the container 110 upward, and therefore the container 110 is pressed against the lower surface of the view angle control film 82. More specifically, the convex portion 111c of the container 110 is pressed against the lower surface of the view angle control film 82. Furthermore, when viewed from above, the convex portion 111c overlaps the light-transmitting adhesive layer 4.

[0022] Here, in this embodiment, the container 110 is arranged upside down compared to a normal container (petri dish). That is, in a normal container, the container body is arranged on the bottom and the cover member is arranged on the top. In contrast, in the container 110 according to this embodiment, the container body 111 is arranged on the top and the cover member 112 is arranged on the bottom.

[0023] In a normal container position, water vapor may be generated from the culture medium 113, and this water vapor may turn into droplets and adhere to the cover member. In this case, the droplets may be present between the optical sensor 81 and the object to be monitored, such as the detection object 114 or the culture medium 113, and these droplets may act as noise or lenses, adversely affecting image acquisition by the optical sensor 81. In contrast, in the container 110 according to this embodiment, the cover member 112 is disposed on the lower side and the culture medium 113 is disposed on the upper side, so that when water vapor is generated from the culture medium 113, the water vapor is absorbed back into the culture medium 113. This prevents water droplets from adhering to the cover member, and prevents the water droplets from adversely affecting image acquisition.

[0024] Fig. 4 is a block diagram showing an example of the configuration of an image acquisition device according to an embodiment. As shown in Fig. 4, the image acquisition device 100 includes an optical sensor 81 and a host IC 75 that controls a light source 7. The optical sensor 81 includes an array substrate 811, a plurality of sensor pixels 812 (photodiodes 813) formed on the array substrate 811, gate line driving circuits 814A and 814B, a signal line driving circuit 815A, and a detection control circuit 816. The array substrate 811 is a glass substrate. The detection control circuit 816 is also referred to as a readout integrated circuit (ROIC).

[0025] Each of the plurality of sensor pixels 812 includes a photodiode 813, a plurality of transistors, and various wirings.

[0026] The array substrate 811 has a detection area AA and a peripheral area GA. The detection area AA is an area where a plurality of sensor pixels 812 (a plurality of photodiodes 813) are provided. The peripheral area GA is an area between the periphery of the detection area AA and the outer edge of the array substrate 811, and is an area where a plurality of sensor pixels 812 are not provided. Gate line driving circuits 814A and 814B, a signal line driving circuit 815A, and a detection control circuit 816 are provided in the peripheral area GA.

[0027] Each of the plurality of sensor pixels 812 is an optical sensor having a photodiode 813 as a sensor element. The photodiode 813 outputs an electrical signal according to the light irradiated thereon.

[0028] The detection control circuit 816 is a circuit that supplies control signals Sa, Sb, and Sc to the gate line driving circuits 814A, 814B and the signal line driving circuit 815A, respectively, and controls their operations. The detection control circuit 816 includes a signal processing circuit that processes the detection signals Vdet from the multiple photodiodes 813.

[0029] The detection control circuit 816 processes the detection signals Vdet from the multiple photodiodes 813, and outputs a sensor value So based on the detection signals Vdet to the host IC 75. In this way, the image acquisition device 100 detects information related to the detection object 114.

[0030] The light source 7 includes a light source substrate 72, a plurality of light emitting elements 71 formed on the light source substrate 72, gate line driving circuits 814C and 814D, a signal line driving circuit 815B, and a light emitting element control circuit 74.

[0031] The plurality of light-emitting elements 71 are arranged in a matrix in an area overlapping with the detection area AA of the light source substrate 72. The light source substrate 72 is a drive circuit substrate that drives each of the plurality of light-emitting elements 85 by switching it between on (lighted state) and off (non-lighted state).

[0032] The light emitting element control circuit 74 is a circuit that supplies control signals Sd, Se, and Sf to the gate line driving circuits 814C, 814D and the signal line driving circuit 815B, respectively, and controls their operations.

[0033] The host IC 75 has a sensor value storage circuit 751, a sensor value calculation circuit 752, a light amount setting circuit 753, and a target value storage circuit 759 as control circuits on the optical sensor 81 side. The sensor value storage circuit 751 stores the sensor value So output from the detection control circuit 816 of the optical sensor 81. The sensor value calculation circuit 752 performs a predetermined calculation process on the sensor value So of the photodiode 813.

[0034] In the light intensity setting mode, the light intensity setting circuit 753 compares the sensor values ​​So detected by the multiple photodiodes 813 with a preset target sensor value So-t acquired from the target value storage circuit 759, and sets the light intensities for detection by the multiple light-emitting elements 71. The target value storage circuit 759 stores the preset target sensor value So-t.

[0035] The host IC 75 has, as control circuits on the light source 7 side, a lighting pattern generation circuit 754 and a lighting pattern storage circuit 755. The lighting pattern storage circuit 755 stores information on the light intensity of each of the plurality of light-emitting elements 71 in the light intensity setting mode.

[0036] The lighting pattern generating circuit 754 generates various control signals based on the information on the amount of light from the lighting pattern storage circuit 755 .

[0037] The host IC 75 further includes an image generation circuit 756. In the detection mode, the image generation circuit 756 generates an image of the detection target 114 based on the sensor values ​​So output from the plurality of photodiodes 813. The image generation circuit 756 is connected to an external host PC 76. The host PC 76 stores the image sent from the image generation circuit 756.

[0038] Next, the configuration of the view angle control film 82 will be described. Fig. 5 is a cross-sectional view schematically showing a collimator layer according to an embodiment. Fig. 6 is a cross-sectional view schematically showing a louver layer according to an embodiment. The collimator layer 82A and the louver layer 82B have the effect of transmitting, toward the optical sensor 81, components of light L emitted from the light source 7 that travel in the vertical direction.

[0039] 5, the view angle control film 82 has a configuration in which, for example, a plurality of light guide portions (holes) 82A1 are provided in a light blocking portion 82A2. In other words, the view angle control film 82 has, for example, cylindrical holes that penetrate the light blocking portion 82A2 in the up-down direction, and these holes become the light guide portions 82A1. This configuration is also called a collimator layer 82A. The light blocking portion 82A2 has a higher light absorption rate than the light guide portions (holes) 82A1. The light guide portions (holes) 82A1 have, for example, a diameter D1.

[0040] 6, the view angle control film 82 has a configuration in which, for example, light-shielding portions 82B2 and light-guiding portions 82B1 are arranged alternately in the left-right direction. This configuration is also called a louver layer 82B. The light-shielding portions 82B2 have a higher light absorption rate than the light-guiding portions 82B1. The light-guiding portions 82B1 have a thickness in the left-right direction of, for example, thickness D2, and the light-shielding portions 82B2 have a thickness in the left-right direction of, for example, thickness D3.

[0041] [Comparative Example] Next, comparative examples will be described. Fig. 7A is a schematic diagram showing a state in which a view angle control film and an optical sensor according to comparative example 1 are attached to a housing. Fig. 7B is a schematic diagram showing a state in which a view angle control film and an optical sensor according to comparative example 2 are attached to a housing.

[0042] As shown in FIG. 7A , the image acquisition device 100A according to Comparative Example 1 includes a housing 3A. The housing 3A includes protrusions 34 at the corners of the top plate 31A and the side plates 32. That is, in the cross section of FIG. 7A , the protrusions 34 protruding downward are provided at the corners where the top plate 31A extending in the left-right direction and the side plates 32 extending in the up-down direction intersect. The protrusions 34 are provided at both left and right ends of the top plate 31A. The protrusions 34 have a rectangular cross section. The optical sensor 81 is adhered to the underside of the top plate 31A via double-sided tape 121. More specifically, in the cross section of FIG. 7A , both left and right ends of the optical sensor 81 are adhered to the underside of the top plate 31A via the double-sided tape 121. The viewing angle control film 82 is adhered to the underside of the protrusions 34 via the double-sided tape 122. 7A, both left and right end portions of the view angle control film 82 are adhered to the undersides of the two protrusions 34 via double-sided tape 121. The view angle control film 82 and the optical sensor 81 are arranged with a slight gap between them in the up and down direction. The gap between the view angle control film 82 and the optical sensor 81 is, for example, 50 μm or more and 600 μm or less.

[0043] As shown in FIG. 7B , the image acquisition device 100B according to Comparative Example 2 includes a housing 3. The housing 3 includes a top plate 31 and side plates 32. The optical sensor 81 is adhered to the lower surface of the top plate 31 via double-sided tape 123. Specifically, in the cross section of FIG. 7B , both left and right end portions of the optical sensor 81 are adhered to the lower surface of the top plate 31 via double-sided tape 123. The view angle control film 82 is adhered to the lower surface of the optical sensor 81 via double-sided tape 124. Specifically, in the cross section of FIG. 7B , both left and right end portions of the view angle control film 82 are adhered to both left and right end portions of the lower surface of the optical sensor 81 via double-sided tape 124. The distance between the view angle control film 82 and the optical sensor 81 is, for example, 50 μm or more and 600 μm or less.

[0044] Fig. 8 is a schematic diagram of an image capturing device according to a comparative example. Fig. 8 shows an aspect of an image capturing device 100B in which a gap is provided between the view angle control film 82 and the optical sensor 81, as in Fig. 7A or 7B.

[0045] The image capturing device 100B according to the comparative example differs from the image capturing device 100 of the embodiment shown in Figures 1 and 2 in that a gap is provided between the view angle control film 82 and the optical sensor 81. This will be explained in detail below.

[0046] 1 and 2, the view angle control film 82 and the optical sensor 81 are bonded via the light-transmitting adhesive layer 4. Therefore, there is no gap between the view angle control film 82 and the light-transmitting adhesive layer 4, and there is no gap between the optical sensor 81 and the light-transmitting adhesive layer 4.

[0047] In contrast to this, in the image acquisition device 100B shown in Fig. 8, as explained with reference to Fig. 7B, a gap is provided in the vertical direction between the view angle control film 82 and the optical sensor 81. That is, when viewed from above, the peripheral edge of the view angle control film 82 and the peripheral edge of the optical sensor 81 are adhered with double-sided tape 124, but inside the double-sided tape 124, the view angle control film 82 and the optical sensor 81 are not adhered.

[0048] Here, when the spring 5 pushes the holding member 2 and the container 110 upward, the convex portion 111c of the container 110 is pressed against the view angle control film 82. Because a gap is provided in the vertical direction between the view angle control film 82 and the optical sensor 81, the portion of the view angle control film 82 against which the convex portion 111c is pressed is recessed upward. As a result, as shown in FIG. 8, vertical distortion is formed in the view angle control film 82.

[0049] Fig. 9 is a photographic image of a culture medium captured by the image acquisition device of the embodiment. Fig. 10 is a photographic image of a culture medium captured by the image acquisition device of Comparative Example 2 shown in Fig. 7B. In Fig. 10, an initial photographic image of a container 110 containing a culture medium 113 (at room temperature) is placed on the left, and a photographic image of the culture medium 113 after 24 hours (at 37°C) is placed on the right.

[0050] As shown in Fig. 9, no interference fringes appear in the photographic image of the culture medium captured by the image acquisition device 100 of the embodiment. However, in the photographic image on the right side of Fig. 10, interference fringes 115 appear in the area A surrounded by the two-dot chain line.

[0051] As described above, the image acquisition device 100 according to the embodiment comprises a light source 7, a holding member 2 positioned above the light source 7 and holding the container 110, a view angle control film 82 positioned above the container 110, a planar optical sensor 81 positioned above the view angle control film 82, a light-transmitting adhesive layer 4 positioned between the view angle control film 82 and the optical sensor 81 and bonding the view angle control film 82 and the optical sensor 81 together, and a spring (elastic member) 5 that pushes the holding member 2 upward to urge the container 110 against the view angle control film 82.

[0052] When the spring 5 pushes the holding member 2 upward to press the container 110 against the view angle control film 82, if there is a gap between the view angle control film 82 and the optical sensor 81 as in Comparative Examples 1 and 2 shown in FIGS. 7A and 7B, the view angle control film 82 and the optical sensor 81 will be distorted as shown in FIG. 8, and interference fringes 115 shown in FIG. 10 will be likely to occur. In particular, when the object to be detected 114 is a microorganism such as a bacterium or a sample containing a microorganism that forms a colony on a culture medium 113 over time, the image acquisition device 100 is placed in an environment with a temperature higher than room temperature. In this way, when the container 110 is pressed against the view angle control film 82 in a high-temperature environment, distortion of the view angle control film 82 and the optical sensor 81 will become greater, and the detection accuracy of the optical sensor may decrease.

[0053] In contrast, in this embodiment, a translucent adhesive layer 4 is disposed between the view angle control film 82 and the optical sensor 81, and the view angle control film 82 and the optical sensor 81 are bonded together by the translucent adhesive layer 4. Therefore, a gap is unlikely to occur between the view angle control film 82 and the translucent adhesive layer 4, and a gap is also unlikely to occur between the optical sensor 81 and the translucent adhesive layer 4. Therefore, in this embodiment, even in a high-temperature environment and when the container 110 is pressed against the view angle control film 82, distortion of the view angle control film 82 and the optical sensor 81 is unlikely to occur, and interference fringes are not generated as shown in FIG. 9, resulting in higher detection accuracy by the optical sensor 81.

[0054] A predetermined gap is provided between the optical sensor 81 and the view angle control film 82, and the predetermined gap is filled with the light-transmitting adhesive layer 4.

[0055] As mentioned above, in comparative examples 1 and 2 shown in Figures 7A and 7B, if there is a gap between the view angle control film 82 and the optical sensor 81, interference fringes 115 are likely to occur, and the detection accuracy of the optical sensor 81 may decrease.

[0056] In contrast, in this embodiment, the specified gap is filled with a translucent adhesive layer 4, so in this embodiment, even in a high-temperature environment and when the container 110 is pressed against the view angle control film 82, distortion of the view angle control film 82 and the optical sensor 81 is less likely to occur, and the detection accuracy of the optical sensor 81 is improved.

[0057] The container is a petri dish. The petri dish has a convex portion 111c that protrudes toward the view angle control film side and is pressed against the view angle control film 82. When viewed from above, the light-transmitting adhesive layer 4 overlaps with the convex portion 111c.

[0058] A large force is locally applied to the portion of the view angle control film 82 against which the convex portion 111c of the Petri dish is pressed, resulting in greater distortion of the view angle control film 82. However, when viewed from above, the light-transmitting adhesive layer 4 overlaps with the convex portion 111c, so the distortion of the view angle control film 82 and the optical sensor 81 is dispersed and reduced, and the detection accuracy of the optical sensor 81 is improved.

[0059] The optical sensor 81 has a glass substrate (array substrate 811). By making the refractive index of the glass substrate (array substrate 811) closer to the refractive index of the light-transmitting adhesive layer 4, blurring of the captured image can be suppressed, and degradation of image quality can be further suppressed.

[0060] The refractive index of the light-transmitting adhesive layer 4 is a value between the refractive index of the optical sensor 81 and the refractive index of the view angle control film 82 .

[0061] Fresnel reflection is a phenomenon in which a portion of light is reflected when it is incident on an interface between materials with different refractive indices. Therefore, by setting the refractive index of the translucent adhesive layer 4 to a value between the refractive index of the optical sensor 81 and the refractive index of the viewing angle control film 82, Fresnel reflection can be suppressed, and the amount of light that can be taken in by the optical sensor 81 can be increased.

[0062] The refractive index of the light-transmitting adhesive layer 4 is equal to or greater than 1.4 and equal to or less than 1.58, which makes it possible to suppress Fresnel reflection and increase the amount of light that enters the optical sensor 81.

[0063] The thickness of the light-transmitting adhesive layer 4 is 10 μm or more and 500 μm or less.

[0064] If the distance between the object to be detected 114 and the optical sensor 81 is large, the captured image may become blurred and unclear, so it is desirable to make the thickness of the light-transmitting adhesive layer 4 thin. However, if the thickness of the light-transmitting adhesive layer 4 is too thin, the adhesive strength between the view angle control film 82 and the light-transmitting adhesive layer 4 may decrease. Therefore, in order to reduce the distance between the object to be detected 114 and the optical sensor 81 and maintain the adhesive strength between the view angle control film 82 and the light-transmitting adhesive layer 4, the thickness of the light-transmitting adhesive layer 4 is preferably 10 μm or more and 500 μm or less.

[0065] The optical sensor 81 has a plurality of photodiodes 813. Photodiodes have the advantage of having a relatively high linearity of output current with respect to the amount of incident light and a fast response speed.

[0066] The view angle control film 82 may have a configuration in which a plurality of light guiding sections 82B1 and light blocking sections 82B2 are alternately arranged, or a configuration in which a plurality of light guiding sections 82A1 are provided on a light blocking section 82A2. In this way, the view angle control film 82 can block light from oblique directions, thereby suppressing blurring of the image captured by the photodiode 813. [Explanation of symbols]

[0067] 2. Retaining member 3. 3A housing 4 Translucent adhesive layer 5. Springs (elastic members) 7 light source 81 Optical Sensor 82 Viewing Angle Control Film 82A Collimator Layer 82A1 Light guide part (hole) 82A2 Light shielding part 82B Louver layer 82B1 Light guiding section 82B2 Light shielding part 100, 100A, 100B Image acquisition device 101 Detection device 110 container (petri dish) 114 Object to be detected L light

Claims

1. A light source and a holding member positioned above the light source and holding a container containing a detection target; a view angle control film positioned above the container; a planar optical sensor located above the view angle control film; a light-transmitting adhesive layer located between the view angle control film and the optical sensor and adhering the view angle control film and the optical sensor; an elastic member that pushes the holding member upward and urges it to press the container against the view angle control film, Image acquisition device.

2. a predetermined gap is provided between the optical sensor and the view angle control film, and the gap is filled with the light-transmitting adhesive layer; The image acquisition device of claim 1 .

3. the container is a petri dish, the petri dish has a convex portion that protrudes toward the view angle control film and is pressed against the view angle control film, When viewed from above, the transparent adhesive layer overlaps the convex portion.

3. The image acquisition device according to claim 1 or 2.

4. the optical sensor has a glass substrate; The image acquisition device of claim 3 .

5. The refractive index of the transparent adhesive layer is A value between the refractive index of the optical sensor and the refractive index of the viewing angle control film, The image acquisition device of claim 3 .

6. The refractive index of the transparent adhesive layer is 1.4 or more and 1.58 or less. The image acquisition device of claim 5 .

7. The thickness of the transparent adhesive layer is 10 μm or more and 500 μm or less. The image acquisition device of claim 5 .

8. the optical sensor includes a plurality of photodiodes; The image acquisition device of claim 4 .

9. The view angle control film has a plurality of light guiding sections and light blocking sections arranged alternately. The image acquisition device of claim 3 .

10. The viewing angle control film has a plurality of light guide sections provided in a light blocking section. The image acquisition device of claim 3 .

Images