JP2021086123A - Imaging system and method for processing image - Google Patents

Abstract

To provide an imaging system that can precisely specify the positional relation between the imaging visions of a plurality of microscope units.SOLUTION: An imaging system 1 includes: a stage 20 which can move in a first direction and in a second direction perpendicular to the first direction; a plurality of microscope units 10A and 10B arranged in parallel along the first direction or the second direction, the units each having a microscope 11 for acquiring an image of an imaging target object mounted on the stage 20 and an imaging device 12 for taking an image of the microscope 11; and a specification unit for specifying the positional relation of the imaging field of view of the first microscope unit 10A and the imaging field of view of the second microscope unit 10B on the basis of the amount of movement of the stage 20 to the first direction and the second direction when a mark arranged in a predetermined position on the stage 20 is moved from the imaging field of view of the first microscope unit into the imaging field of view of the second microscope unit 10B of the first and second microscope units 10A and 10B.SELECTED DRAWING: Figure 2

Description

The disclosed technique relates to a photographing system and an image processing method.

The following technologies are known as technologies related to an imaging system including a plurality of microscope units that capture images of objects mounted on a stage. For example, Patent Document 1 is provided with a stage for placing a sample that can move in at least one direction in one axial direction or the other axial direction in one plane, and the stage is provided so as to straddle the stage in a bridge shape and mutually It includes a plurality of support members provided so that the distance can be adjusted, and a head group each of the plurality of support members provided so as to be able to adjust the mutual distance and consisting of a plurality of microscope heads. A multi-head microscope apparatus is described.

Japanese Unexamined Patent Publication No. 8-171057

Cosmic ray radiography uses charged particles such as muons (μ particles) that have higher permeability than X-rays contained in cosmic rays, so that the inside of the observation object that cannot be observed with X-rays is non-destructive. This is an imaging technology. When obtaining a muon image, a nuclear dry plate for detecting muons is installed around the observation target, and the track of the muon that has passed through the observation target is recorded on the nuclear dry plate. The nuclear emulsion plate is formed by laminating a recording layer having a thickness of about several tens to 100 μm on one side or both sides of a light-transmitting support such as a plastic film. As a material constituting the recording layer, a material in which silver halide crystals are uniformly dispersed in a gelatin film is generally used.

When a charged particle such as a muon passes through a silver halide crystal, its track is retained in the crystal. The crystals holding the tracks of the charged particles remain in the nuclear emulsion as silver particles (black spots) having a size of about 1 μm by developing. The tracks of charged particles that have passed through the nuclear emulsion are recorded as a three-dimensional arrangement of silver particles (sunspots). The three-dimensional arrangement of the silver particles (black dots) is extracted by observation using an optical microscope. By specifying the positional relationship between the tracks of charged particles recorded on the nuclear emulsion, an image of the object to be observed can be derived.

For the tracks of charged particles recorded on the nuclear emulsion, a microscope unit including a microscope and an imaging device is used to determine the positions of the recording layer of the nuclear emulsion mounted on the XY stage in the XY and Z directions. It is extracted by taking a picture. The imaging with the microscope unit is performed a plurality of times while sequentially moving the focal position along the XY and Z directions. Therefore, as the area of the nuclear emulsion increases, the number of times of photographing increases and the photographing time becomes longer. In addition, the moving distance of the XY stage becomes long, and a more expensive XY stage is required.

As a method for solving this problem, a method using a plurality of microscope units can be considered. The imaging time can be shortened by having a plurality of microscope units share the imaging range and perform parallel operations. In addition, the moving distance of the XY stage can be shortened. However, in this case, in order to extract the tracks of the charged particles recorded on the nuclear emulsion from the images taken by each of the plurality of microscope units, the positional relationship of the imaging fields of each of the plurality of microscope units (that is, that is, It is necessary to specify the positional relationship of the images taken by each of the microscope units) with an accuracy of micron order.

Although it is possible to specify the positional relationship of the imaging fields of the microscope units from the mounting positions of a plurality of microscope units, it is difficult to specify them with micron-order accuracy. In this case, the images taken by each of the plurality of microscope units cannot be properly stitched together, and it becomes difficult to extract the tracks of the charged particles.

The disclosed technique has been made in view of the above points, and an object thereof is to specify the positional relationship of each imaging field of view of a plurality of microscope units with high accuracy.

The imaging system according to the disclosed technique is juxtaposed with a stage movable in a first direction and a second direction orthogonal to the first direction, and along at least one of the first direction and the second direction. A plurality of microscope units each equipped with a microscope for acquiring an image of an object to be imaged mounted on the stage and an imaging device for capturing the image acquired by the microscope, and marks arranged at predetermined positions on the stage. Was moved from within the imaging field of view of the first microscope unit among the plurality of microscope units to within the imaging field of view of the second microscope unit among the plurality of microscope units, in the first direction of the stage and at the first position. Includes a specific portion that specifies the positional relationship between the imaging field of view of the first microscope unit and the imaging field of view of the second microscope unit based on the amount of movement in the two directions.

The specific unit may derive coordinate values in a common coordinate system for images taken by each of the plurality of microscope units based on the specified positional relationship.

The specific part is based on the position coordinates of the stage when the mark is located in the field of view of the first microscope unit and the position coordinates of the stage when the mark is located in the field of view of the second microscope unit. , The positional relationship between the imaging field of view of the first microscope unit and the imaging field of view of the second microscope unit may be specified.

The imaging system derives the tilt angle of the coordinate axes in the imaging field with respect to the first direction or the second direction for each of the plurality of microscope units, and makes the tilt angle for the image captured by each of the plurality of microscope units. A correction unit that performs rotation correction according to the situation may be further included.

The correction unit refers to the microscope unit based on the moving direction of the mark placed on the stage in the imaging field of view of the microscope unit when the stage is moved along the first direction or the second direction. The tilt angle may be derived.

The placement interval of the plurality of microscope units juxtaposed along the first direction is the length of the object to be imaged in the first direction divided by the number of juxtaposed microscope units along the first direction. It is preferable that the value corresponds to the above value.

The imaging system may further include a moving mechanism that moves the focal position of each of the plurality of microscope units along a third direction orthogonal to both the first and second directions.

The moving mechanism may include a first moving mechanism that integrally moves the focal position of each of the plurality of microscope units along a third direction. Further, the moving mechanism may include a second moving mechanism that individually moves the focal position of each of the plurality of microscope units along the third direction.

The imaging system may further include a control unit that controls each microscope unit to instruct the microscope unit to perform imaging based on the focal position of the microscope unit in the third direction.

The imaging system further includes an illuminating device that irradiates the imaging object at each imaging position of the plurality of microscope units from the opposite side of each of the plurality of microscope units with the imaging object in between. You may.

The illuminating device may include a single light source and an optical system configured to divide the light from the light source and irradiate each imaging position of the plurality of microscope units with the illuminating light.

The imaging system may be provided corresponding to each of the plurality of microscope units and may further include a detector that detects the height of the imaging object at the imaging position of the corresponding microscope units.

It is preferable that the optical performance of the microscope included in each of the plurality of microscope units is the same, and the imaging performance of the imaging apparatus provided in each of the plurality of microscope units is the same.

The plurality of microscope units were arranged at a distance of a first microscope, a second microscope separated from the first microscope in a first direction, and a second direction from the first microscope. Even if a third microscope and a fourth microscope arranged apart from the second microscope in the second direction and separated from the third microscope in the first direction are included. Good.

The imaging method of the disclosed technique is juxtaposed with a stage that is movable in a first direction and a second direction orthogonal to the first direction, and along at least one of the first direction and the second direction. A plurality of microscope units of an imaging system including a microscope for acquiring an image of an object to be imaged, each mounted on a stage, and a plurality of microscope units equipped with an imaging device for capturing an image acquired by the microscope. It is a method of processing an image taken by each of the above, and a mark placed at a predetermined position on a stage is placed in a plurality of microscope units from within the imaging field of the first microscope unit among the plurality of microscope units. Imaging of the first microscope unit and imaging of the second microscope unit based on the amount of movement in the first and second directions of the stage when moved into the imaging field of the second microscope unit. Includes identifying the positional relationship of the visual field.

The image processing method according to the disclosed technique may further include deriving coordinate values in a common coordinate system for images taken by each of the plurality of microscope units based on the specified positional relationship.

In the disclosed technique, the image processing method derives the tilt angle of the coordinate axes in the captured image with respect to the first direction or the second direction for each of the plurality of microscope units, and is photographed by each of the plurality of microscope units. It may further include performing rotation correction according to the tilt angle of the image.

According to the disclosed technique, it is possible to specify the positional relationship of each of the imaging fields of the plurality of microscope units with high accuracy.

It is sectional drawing which shows an example of the structure of the nuclear dry plate which concerns on embodiment of the disclosed technique. It is a perspective view which shows an example of the structure of the photographing system which concerns on embodiment of the disclosed technique. It is a top view which shows an example of the positional relationship of the 1st and 2nd microscope units which concerns on embodiment of the disclosed technique. It is a figure which shows an example of the structure of the 1st and 2nd microscope units and the lighting apparatus which concerns on embodiment of the disclosed technique. It is a figure which shows an example of the hardware configuration of the information processing apparatus which concerns on embodiment of the disclosed technique. It is a functional block diagram which shows an example of the functional structure of the information processing apparatus which concerns on embodiment of the disclosed technique. It is sectional drawing which shows the movement path of the focal position of the 1st and 2nd microscope units which concerns on embodiment of the disclosed technique. It is a top view which shows the movement path of the focal position of the 1st and 2nd microscope units which concerns on embodiment of the disclosed technique. It is a figure which shows an example of the mark which concerns on embodiment of the disclosed technique. It is a figure which shows an example of the mark which concerns on embodiment of the disclosed technique. It is a top view which shows the preferable arrangement of the mark on the film which marked the mark which concerns on embodiment of the disclosed technique. It is a flowchart which shows an example of the flow of the positional relationship specifying process which concerns on embodiment of the disclosed technique. It is a figure which shows the state which the coordinate axis of the photographing field of view of the 1st and 2nd microscope units which concerns on embodiment of the disclosed technique is not inclined with respect to X direction and Y direction. It is a figure which shows the state which the coordinate axis of the imaging field of view of the 1st and 2nd microscope units which concerns on embodiment of the disclosed technique is inclined by the inclination angle θ with respect to X direction and Y direction. It is a flowchart which shows an example of the flow of the image correction processing which concerns on embodiment of the disclosed technique. It is a figure which shows the state of movement of the mark in the photographing field of view of the 1st microscope unit which concerns on embodiment of the disclosed technique. It is a figure which shows the state of movement of the mark in the photographing field of view of the 1st microscope unit which concerns on embodiment of the disclosed technique. It is a top view which shows an example of the positional relationship of four microscope units provided in the imaging system which concerns on another embodiment of the disclosed technique. FIG. 5 is a plan view showing a preferred arrangement of marks according to other embodiments of the disclosed technique. It is a figure which shows an example of the structure of the lighting apparatus which concerns on other embodiment of the disclosed technique.

Hereinafter, embodiments of the disclosed technology will be described with reference to the drawings. In each drawing, substantially the same or equivalent components or parts are designated by the same reference numerals.

First, a nuclear dry plate as an object to be photographed in the photographing system 1 (see FIG. 2) according to the embodiment of the disclosed technique will be described. FIG. 1 is a cross-sectional view showing an example of the configuration of a nuclear emulsion plate NP.

The nuclear emulsion NP is obtained by laminating a track recording layer EL having a thickness of about several tens to 100 μm on both sides of a light-transmitting support FB such as a plastic film. The track recording layer EL is a layer that records the tracks of charged particles as a latent image by transmitting charged particles such as muons. As a recording material constituting the track recording layer EL, it is possible to use a material in which silver halide crystals are uniformly dispersed in a gelatin film. When the charged particles pass through the track recording layer containing silver halide crystals, the tracks are recorded as a latent image on the track recording layer EL. By developing the track recording layer EL on which the latent image is recorded, the tracks of the charged particles are held in the track recording layer EL as a three-dimensional arrangement of silver particles (black dots).

As a sensitive material other than silver halide, for example, an iron salt photosensitive material containing a ferric oxalate salt or a diazo photosensitive material containing an aromatic diazonium salt can also be used. The iron salt photosensitive material has a property of absorbing photons and developing a color, and is used for, for example, blueprint photosensitive paper. The diazo photosensitive material is a so-called positive photosensitive material in which an unexposed portion develops color by development, and is used for, for example, diazo photosensitive paper. When the nuclear emulsion NP is used for the purpose of extracting tracks of charged particles, silver halide is most preferable from the viewpoint of sensitivity to charged particles.

The non-electric gamma ray itself does not form a track on the nuclear emulsion NP, but since the gamma ray changes into an electron and a positron when it reacts with a substance, the track is recorded on the nuclear emulsion NP as a latent image. Neutrons also do not directly expose the nuclear emulsion, but when they collide with protons in matter, the tracks of the protons are recorded on the nuclear emulsion NP. That is, the track of the charged particle recorded on the nuclear emulsion NP also includes the track of the charged particle secondarily generated by the collision with the gamma ray or the neutron ray.

In the non-destructive inspection using the nuclear emulsion NP, the nuclear emulsion NP is installed around the inspection target, and the nuclear emulsion NP is collected after a predetermined period such as several weeks has elapsed. Next, the recovered nuclear dry plate NP is developed, and the tracks of charged particles such as muons recorded on the nuclear dry plate NP are extracted from a plurality of tomographic images obtained by photographing the developed nuclear dry plate NP. Then, the density distribution of the inspection target is obtained by the analysis process using the extracted tracks.

FIG. 2 is a perspective view showing an example of the configuration of the photographing system 1 according to the embodiment of the disclosed technique. The photographing system 1 includes an XY stage 20, a first microscope unit 10A, a second microscope unit 10B, a first moving mechanism 31, a second moving mechanism 35, a detector 40, a lighting device 50 (see FIG. 4), and a lighting device 50. It is configured to include an information processing device 60. The photographing system 1 is used in an application in which the nuclear dry plate NP mounted on the main surface 20S of the XY stage 20 is photographed by the first microscope unit 10A and the second microscope unit 10B.

The main surface 20S of the XY stage can move in the X direction and the Y direction. The X and Y directions are orthogonal to each other and are parallel to the main surface 20S of the XY stage 20, and therefore also to the main surface of the nuclear emulsion NP mounted on the XY stage 20. The XY stage 20 includes a motor 21 for moving the main surface 20S in the X direction and a motor 22 for moving the main surface 20S in the Y direction. As the XY stage 20, for example, one using a precision lead screw can be used, and positioning is possible with an accuracy of 0.1 μm. The XY stage 20 includes a holder 23 that vacuum-adsorbs the nuclear dry plate NP, and the illumination light from the lighting device 50 (see FIG. 4) is introduced into the nuclear dry plate NP in the mounting area of the nuclear dry plate NP of the holder 23. A transparent glass 24 is attached to the surface.

The first microscope unit 10A and the second microscope unit 10B are juxtaposed along the X direction. The first and second microscope units 10A and 10B are a microscope 11 for acquiring an image of a nuclear emulsion NP mounted on the XY stage 20, and an imaging device 12 for capturing an image acquired by the microscope 11, respectively. Has an integrated configuration with. The first and second microscope units 10A and 10B share the imaging range and perform parallel operations.

The first and second microscope units 10A and 10B are attached to the support members 32 extending along the X direction, and their positional relationship with each other is fixed. FIG. 3 is a plan view showing an example of the positional relationship between the first and second microscope units 10A and 10B.

Here, assuming that the arrangement interval of a plurality of microscope units juxtaposed along the X direction is D, the length of the nuclear emulsion NP in the X direction is W, and the number of microscope units juxtaposed along the X direction is n. It is preferable to satisfy the following equation (1).
D = W / n ... (1)

As a result, the imaging range shared by each of the plurality of microscope units can be made uniform, so that the moving distance in the X direction on the XY stage 20 can be minimized. In the present embodiment, since the number of microscope units juxtaposed along the X direction is two (n = 2), the arrangement interval D of the first microscope unit 10A and the second microscope unit 10B is W. It is preferably / 2.

FIG. 4 is a diagram showing an example of the configuration of the first and second microscope units 10A and 10B and the illumination device 50. The first microscope unit 10A and the second microscope unit 10B have the same configuration as each other. That is, the first and second microscope units 10 have the same optical performance of the microscope 11, and the imaging performance of the imaging device 12 provided therein is also the same. In addition, "equal optical characteristics" means that the magnification of the objective lens 11o and the occurrence of Seidel's five aberrations are the same. “Equivalent imaging performance” means that the number of pixels of the image sensor 12A is equivalent.

The first and second microscope units 10A and 10B include an objective lens 11o, an imaging lens 11i, and an image sensor 12A. As the objective lens 11o, for example, a plan-type apochromat objective lens having a magnification of 20 times that of immersion can be preferably used. This makes it possible to obtain the desired resolution, depth of field and flatness of the read image plane. The infinity correction optical system is composed of the objective lens 11o and the imaging lens 11i, and the light passing through the objective lens 11o enters the imaging lens 11i as a parallel light beam at infinity, and the imaging lens 11i causes the imaging element 12A to enter. An image is formed on the imaging surface. As the image sensor 12A, for example, a monochrome sensor having 5000 × 5000 pixels can be used.

The illumination device 50 sandwiches the nuclear dry plate NP between the imaging positions of the first and second microscope units 10A and 10B, and illuminates the light from the side opposite to the first and second microscope units 10A and 10B. Irradiate. The lighting device 50 constitutes a Koehler illumination system, and includes a strobe light source 51, a condenser lens 52, a field diaphragm 53, an aperture diaphragm 54, and a condenser lens 55. As the strobe light source 51, for example, a blue LED (Light Emitting Diode) can be used. This makes it possible to further increase the resolution of the microscope and at the same time reduce the depth of field to increase the resolution of the image of the nuclear emulsion NP in the depth direction. The strobe light source 51 emits light in accordance with the imaging timing of the first and second microscope units 10A and 10B. In this embodiment, each component of the illumination device 50 shown in FIG. 4 is provided for each of the first and second microscope units 10A and 10B.

The first moving mechanism 31 and the second moving mechanism 35 make the focal positions of the first and second microscope units 10A and 10B perpendicular to both the X and Y directions (that is, the XY stage 20). It is moved along the Z direction (the direction perpendicular to the main surface 20S).

The first moving mechanism 31 includes a support member 32 extending along the X direction and a pair of columns 33 connected to one end and the other end of the support member 32 and extending along the Z direction. It is composed of. The first and second microscope units 10A and 10B are attached to the support member 32. The support member 32 can move in the Z direction along the support column 33. The first moving mechanism 31 is configured so that when the support member 32 moves in the Z direction along the support column 33, the positions of one end and the other end of the support member 32 in the Z direction are always the same. There is. When the support member 32 moves along the Z direction, the focal positions of the first and second microscope units 10A and 10B move integrally along the Z direction.

The second moving mechanism 35 is provided in the first and second microscope units 10A and 10B, respectively. The second moving mechanism 35 moves the objective lenses 11o of the first and second microscope units 10A and 10B individually, thereby moving their focal positions individually along the Z direction. Since the first and second microscope units 10A and 10B constitute an infinity correction optical system, the emitted light from the objective lens 11o is parallel light, and the focal position is moved in the optical axis direction by the movement of the objective lens 11o. It is possible to move along. The second moving mechanism 35 may be configured to move the entire first and second microscope units 10A and 10B individually along the Z direction.

As described above, the photographing system 1 includes two types of moving mechanisms as a mechanism for moving the focal positions of the first and second microscope units 10A and 10B along the Z direction. As a result, for example, when the focal position is moved by a relatively long distance (that is, when the focal position is roughly adjusted), the first moving mechanism 31 is operated to move the focal position by a relatively short distance. (That is, when finely adjusting the focal position), the second moving mechanism 35 can be operated properly.

Further, when the imaging system 1 is provided with the second moving mechanism 35 for individually moving the focal positions of the first and second microscope units 10A and 10B, for example, when the nuclear emulsion NP is warped. The focal positions of the first and second microscope units 10A and 10B can be made different from each other depending on the warp. As a result, in each of the first and second microscope units 10A and 10B, the movement range of the focal position along the Z direction can be minimized, and the imaging system 1 includes only the first movement mechanism 31. The shooting time can be shortened as compared with.

As a mechanism for moving the focal positions of the first and second microscope units 10A and 10B along the Z direction, only the first moving mechanism 31 or only the second moving mechanism 35 may be provided. Good. As a result, the device configuration can be simplified and the device cost can be reduced as compared with the configuration including both the first moving mechanism 31 and the second moving mechanism 35.

The detector 40 is provided in the first and second microscope units 10A and 10B, respectively. The detector 40 includes, for example, a displacement meter using a laser beam, and detects the height of the nuclear emulsion NP at the imaging position of the corresponding microscope unit. By detecting the height of the nuclear dry plate NP by the detector 40, the amount of warpage of the nuclear dry plate at the imaging position can be grasped. Thereby, in the first and second microscope units 10A and 10B, it is possible to adjust the focal position according to the amount of warpage of the nuclear emulsion. For example, in the nuclear dry plate NP, when a warp occurs in the direction approaching the microscope unit, the position away from the nuclear dry plate NP in the Z direction by a distance corresponding to the amount of the warp with respect to the imaging start reference position in the Z direction is set. It may be defined as the imaging start position in the Z direction of the microscope unit.

The information processing device 60 controls the photographing system 1 in an integrated manner. In addition, the information processing device 60 stores images taken by the first and second microscope units 10A and 10B. In addition, the information processing device 60 performs image processing on the images captured by the first and second microscope units 10A and 10B.

FIG. 5 is a diagram showing an example of the hardware configuration of the information processing device 60. The information processing device 60 includes a CPU (Central Processing Unit) 61, a memory 62 as a temporary storage area, and a non-volatile storage unit 63. Further, the information processing device 60 includes a display unit 64 such as a liquid crystal display, an input unit 65 including a keyboard and a mouse, a network I / F (InterFace) 66 connected to a network, and an external I / F 67. The information processing device 60 includes a first and second microscope units 10A and 10B, an XY stage 20, a first moving mechanism 31, a second moving mechanism 35, a detector 40, and a lighting device via an external I / F 67. Connected to 50.

The CPU 61, the memory 62, the storage unit 63, the display unit 64, the input unit 65, the network I / F66, and the external I / F67 are connected to the bus 68. The information processing device 60 may be, for example, a personal computer or a server computer.

The storage unit 63 is realized by an HDD (Hard Disk Drive), an SSD (Solid State Drive), a flash memory, or the like. The storage unit 63 stores a shooting control program 71, a positional relationship specifying program 72, and an image correction program 73. The CPU 30 reads each of the above programs from the storage unit 63, expands the program into the memory 62, and executes the expanded program. Further, the storage unit 63 stores the images taken by the first and second microscope units 10A and 10B.

FIG. 6 is a functional block diagram showing an example of the functional configuration of the information processing device 60. The information processing device 60 includes a control unit 81, a specific unit 82, and a correction unit 83. The information processing device 60 functions as a control unit 81 when the CPU 61 executes the photographing control program 71. Further, the information processing device 60 functions as the identification unit 82 when the CPU 61 executes the positional relationship identification program 72. Further, the information processing device 60 functions as a correction unit 83 when the CPU 61 executes the image correction program 73.

The control unit 81 controls the drive of the XY stage 20, the first moving mechanism 31 and the second moving mechanism 35, and at the same time, the imaging timing in the first and second microscope units 10A and 10B and the light emission timing in the lighting device 50. To control.

7 and 8 are cross-sectional views and plan views showing the moving paths of the focal positions of the first and second microscope units 10A and 10B, respectively. In FIGS. 7 and 8, the movement path of the focal position is indicated by a dotted arrow. Under the imaging control by the control unit 81, the first and second microscope units 10A and 10B each perform imaging of the nuclear emulsion NP while changing the focal position downward in the Z direction for one imaging field of view 90. The field of view 90 is one field of view on the XY plane by the first and second microscope units 10A and 10B. The movement of the focal position in the Z direction is performed by the second moving mechanism 35 moving the objective lens 11o along the Z direction. Changing the focal position downward in the Z direction means moving the objective lens 11o in the direction approaching the nuclear emulsion NP along the Z direction. Further, in FIG. 7, the tracks of the charged particles are shown by black dots, and the arrangement of the black dots is shown by a dashed line.

The second moving mechanism 35 provided in each of the first and second microscope units 10A and 10B supplies a position signal indicating the position of the objective lens 11o of each microscope unit to the control unit 81. When the control unit 81 determines that the focal position in the Z direction indicated by this position signal has reached a predetermined position, the control unit 81 supplies a control signal instructing the corresponding microscope unit to take a picture. That is, the control unit 81 controls the imaging timing of each of the first and second microscope units 10A and 10B based on the focal position in the Z direction for each microscope unit. Further, the control unit 81 supplies a control signal instructing the corresponding lighting device 50 to emit light in accordance with the respective imaging timings of the first and second microscope units 10A and 10B. As a result, each of the first and second microscope units 10A and 10B photographs the track recording layer EL for each imaging field of view 90 each time the focal position in the Z direction moves by, for example, 1 μm. The strobe light source 51 of the lighting device 50 emits light in accordance with the imaging timing of the first and second microscope units 10A and 10B.

When photographing the nuclear dry plate NP, the detector 40 detects the height of the nuclear dry plate NP at the imaging position of the corresponding microscope unit, and supplies a detection signal indicating the detected height to the control unit 81. The control unit 81 is, for example, based on the detection signal supplied from the detector 40 provided in the first microscope unit 10A, at the imaging position of the first microscope unit 10A of the nuclear emulsion NP, the first microscope unit When it is determined that the warp occurs in the direction approaching 10A, the position away from the nuclear emulsion NP in the Z direction by a distance corresponding to the amount of the warp with respect to the imaging start reference position in the Z direction is set by the first microscope unit. It is defined as the shooting start position in the Z direction of 10A. Similarly, in the second microscope unit 10B, the imaging start position in the Z direction is determined according to the amount of warpage of the nuclear emulsion NP at the imaging position of the second microscope unit 10B.

When the tomographic image has been taken for one field of view 90 in each of the first and second microscope units 10A and 10B, the XY stage 20 is set in the X direction or based on the control signal supplied from the control unit 81. It moves one field of view along the Y direction. As a result, the focal positions of the first and second microscope units 10A and 10B move to the adjacent imaging field of view 90. The first and second microscope units 10A and 10B perform imaging of the track recording layer EL in the new imaging field of view 90 while changing the focal position upward in the Z direction in the same manner as described above. Changing the focal position upward in the Z direction means moving the objective lens 11o in the direction away from the nuclear emulsion plate NP along the Z direction.

The first and second microscope units 10A and 10B perform the above imaging process for each imaging field of view 90. Therefore, a plurality of tomographic images can be obtained for each imaging field of view 90. In the obtained tomographic image, the tracks of charged particles appear as black spots. The control unit 81 stores each of the tomographic images taken by the first and second microscope units 10A and 10B in the storage unit 63. The positional relationship between the first and second microscope units 10A and 10B is maintained constant during the imaging period. The first and second microscope units 10A and 10B share the imaging range and perform parallel operations.

The specific unit 82 displays the mark 92 (see FIGS. 9A and 9B), which will be described later, arranged at a predetermined position on the XY stage 20 from the imaging field of view of the first microscope unit 10A to the imaging field of view of the second microscope unit 10B. The positional relationship between the imaging field of view of the first microscope unit 10A and the imaging field of view of the second microscope unit 10B is specified based on the amount of movement of the XY stage 20 in the X and Y directions when the stage 20 is moved inward. Further, the specifying unit 82 derives coordinate values in a common coordinate system for the images taken by each of the first and second microscope units 10A and 10B based on the specified positional relationship.

9A and 9B are diagrams showing an example of the mark 92 used for specifying the positional relationship of the imaging fields of the first and second microscope units 10A and 10B. The mark 92 is marked on a transparent film of the same size as the nuclear emulsion NP. The film marked with the mark 92 is mounted on the XY stage 20 instead of the nuclear emulsion NP and is observed by the first and second microscope units 10A and 10B.

As shown in FIG. 9A, the mark 92 may be composed of two intersecting straight lines having a width of several microns. Further, as shown in FIG. 9B, the mark 92 may be composed of dots having a diameter of about several microns and a plurality of straight lines having a width of several microns arranged around the dots. The mark 92 is sized to fit within the imaging field of view of the first and second microscope units 10A and 10B. The mark 92 may have a shape whose position can be recognized by the first and second microscope units 10A and 10B, and is not limited to the above.

FIG. 10 is a plan view showing a preferable arrangement of the mark 92 on the film 94 on which the mark 92 is marked. As shown in FIG. 10, the mark 92 is located at any position on the straight line V1 passing through the midpoint of the straight line H1 connecting the optical axes of the first and second microscope units 10A and 10B and orthogonal to the straight line H1. It is preferable to be arranged. By arranging the mark 92 at any position on the straight line V1, the mark 92 is observed in each of the first and second microscope units 10A and 10B by moving the XY stage 20 in the X and Y directions. It becomes possible to do.

The information processing device 60 functions as the identification unit 82 by executing the positional relationship identification program 72 by the CPU 61, and executes the positional relationship identification process described below. FIG. 11 is a flowchart showing an example of the flow of the positional relationship specifying process.

In step S1, the specific unit 82 acquires the position coordinates (X1, Y1) of the XY stage 20 when the mark 92 is located in the photographing field of view (for example, the center of the photographing field of view) of the first microscope unit 10A. In step S2, the identification unit 82 acquires the position coordinates (X2, Y2) of the XY stage 20 when the mark 92 is located in the photographing field of view (for example, the center of the photographing field of view) of the second microscope unit 10B. The specific unit 82 may acquire the position coordinates output from the encoder attached to the XY stage 20, or may acquire the position coordinates input by the user via the input unit 65. The process of driving the XY stage to position the mark 92 in the field of view of the first and second microscope units 10A and 10B can be performed automatically or manually.

In step S3, the identification unit 82 of the first and second microscope units 10A and 10B based on the position coordinates (X1, Y1) acquired in step S1 and the position coordinates (X2, Y2) acquired in step S2. Identify the positional relationship of the shooting field of view. Specifically, the specific unit 82 derives the difference (ΔX, ΔY) between (X1, Y1) and (X2, Y2). However, ΔX = X2-X1 and ΔY = Y2-Y1. The position of the mark 92 in the field of view of the first microscope unit 10A when the position coordinates (X1, Y1) are acquired, and the position of the second microscope unit 10B when the position coordinates (X2, Y2) are acquired. When the position of the mark 92 in the field of view is deviated, it is preferable to add or subtract the amount corresponding to the deviated amount to the difference (ΔX, ΔY).

In step S4, the identification unit 82 is photographed by the first and second microscope units 10A and 10B based on the positional relationship of the imaging fields of the first and second microscope units 10A and 10B identified in step S3. For the image, the coordinate values in the common coordinate system (global coordinate system) are derived.

The position of the image taken by the first microscope unit 10A is specified by the local coordinate values (Xa, Ya) in the local coordinate system unique to the first microscope unit 10A. Similarly, the position of the image taken by the second microscope unit 10B is specified by the local coordinate values (Xb, Yb) in the local coordinate system specific to the second microscope unit 10B. Here, it is assumed that the local coordinate values (Xa, Ya) in the first microscope unit 10A are applied as the global coordinate values in the global coordinate system. In this case, the specific unit 82 adds a difference (ΔX, ΔY) to the local coordinate values (Xb, Yb) in the second microscope unit 10B, so that the identification unit 82 has global coordinates for the image taken by the second microscope unit 10B. The values (Xb + ΔX, Yb + ΔY) are derived. That is, the specific unit 82 derives the coordinate values (global coordinate values) in the common coordinate system (global coordinate system) for the images taken by the first and second microscope units 10A and 10B. As a result, the images taken by each of the first and second microscope units 10A and 10B can be appropriately stitched together.

The positional relationship between the first and second microscope units 10A and 10B can be specified by the specific unit 82 by, for example, adjusting the tilt of the lens barrels of the first and second microscope units 10A and 10B. This may be carried out when the positional relationship of the imaging fields of the microscope units 10A and 10B of the above is changed.

The correction unit 83 derives the tilt angle of the coordinate axis of the photographing field of view with respect to the X direction or the Y direction for each of the first and second microscope units 10A and 10B, and the correction unit 83 derives the inclination angle of the first and second microscope units 10A and 10B. Rotation correction is performed on the images taken by each of them according to the above-mentioned tilt angle. Here, the coordinate axes of the imaging fields of the first and second microscope units 10A and 10B are the coordinate axes in the local coordinate system of the microscope units, and also the coordinate axes of the images captured by these microscope units. The inclination angle with respect to the X direction or the Y direction is an inclination angle with respect to the moving direction of the XY stage 20 (coordinate axes in the coordinate system of the XY stage 20).

Figure 12 shows first and second microscope unit 10A, coordinate axes _X V and 10B of the field of view 90, _{Y V} is, X direction which is the moving direction of the XY stage 20, a state in which no inclined with respect to the Y direction It is a figure. On the other hand, FIG. 13, first and second microscope unit 10A, coordinate axes _X V and 10B of the field of view 90, _{Y V} is, X direction which is the moving direction of the XY stage 20, inclined in the negative direction with respect to the Y-direction It is a figure which shows the state which is tilted at an angle θ. The first and second microscope units 10A and 10B may have different viewing angles from each other.

When the coordinate axes of the imaging fields of the first and second microscope units 10A and 10B are tilted with respect to the X and Y directions, which are the moving directions of the XY stage 20, the first and second microscope units 10A and 10B Unless the rotation correction is performed for the images taken by each of the above images according to the tilt angle, the images cannot be properly stitched together. The correction unit 83 corrects the rotation of the images according to the inclination of the imaging field of view of the first and second microscope units 10A and 10B, so that the images can be appropriately stitched together.

The information processing device 60 functions as a correction unit 83 when the CPU 61 executes the image correction program 73, and performs the image correction process described below. FIG. 14 is a flowchart showing an example of the flow of the image correction process. In the following, a case where image correction processing is performed on the image captured by the first microscope unit 10A will be described as an example.

_{In step S11, the correction unit 83 acquires the position coordinates (X V1} , Y _V1 ) of the mark 92 in the field of view of the first microscope unit 10A. Prior to the process in this step, the XY stage 20 is driven to position the mark 92 within the imaging field of view of the first microscope unit 10A. The correction unit 83 may acquire _{the position coordinates (X V1} , Y _V1 ) input by the user via the input unit 65.

In step S12, the correction unit 83 moves the XY stage 20 by a predetermined distance along the X direction, and then the position coordinates (X _V2 , Y _{V2) of the mark 92 in the imaging field of view of the first microscope unit 10A.} ) To get. Prior to the process in this step, the XY stage 20 is driven to move the mark 92 within the imaging field of view of the first microscope unit 10A. The correction unit 83 may acquire _{the position coordinates (X V2} , Y _V2 ) input by the user via the input unit 65.

In step S13, the correction unit 83 determines the tilt angle θ of the coordinate axis of the imaging field of view of the first microscope unit 10A with respect to the X direction based on _{the position coordinates (X V1} , Y _V1 ) and (X _V2 , Y _V2). Derived.

Here, FIGS. 15 and 16, the coordinate axis _X V of the field of view of the first microscope unit 10A, _{Y V} is the coordinate axis X of the XY stage 20, in a case where inclined at an inclination angle θ with respect to Y, XY It is a figure which shows the state of the movement of the mark 92 in the field of view 90 of the first microscope unit 10A when the stage 20 is moved along the X direction. As shown in FIG. 15, coordinate axes _X V of the field of view 90 of the first microscope unit 10A, _{Y V} is, the coordinate axis X of the XY stage 20, in a case where inclined at an inclination angle θ with respect to Y, XY stage 20 the to motions in the X direction, the mark 92 is moved in a direction inclined θ relative to the coordinate axes X _V of the field of view 90. That is, by deriving the movement direction of the mark 92 in the first microscope unit 10A of the field of view 90, the coordinate axis _X V of the field of view 90, the _{Y V} coordinate axis X of the XY stage 20, Y (i.e. XY stage 20 It is possible to derive the inclination angle θ with respect to the moving direction of. The moving direction of the mark 92 can be derived from the position coordinates before the movement (X _V1 , Y _V1 ) and one coordinate after the movement (X _V2 , Y _V2). That is, the inclination angle θ can be obtained by the following equation (2).
θ = arctan {(Y _V2- Y _V1 ) / (X _V2- X _V1 )} ... (2)

In this way, the correction unit 83 derives the inclination angle θ based on the moving direction of the mark 92 in the photographing field of view 90 when the XY stage 20 is moved along the X direction.

In step S14, the correction unit 83 performs rotation correction by rotating each of the images captured by the first microscope unit 10A in the opposite direction by an angle equal to the tilt angle θ derived in step S13. The correction unit 83 also performs the same rotation correction on the image captured by the second microscope unit 10B.

In this way, the correction unit 83 performs rotation correction on the images captured by the first and second microscope units 10A and 10B according to the inclination of the respective imaging fields of view, thereby joining the images. It will be possible to do it properly. The correction unit 83 derives the tilt angle of the coordinate axes of the shooting field of view with respect to the Y direction based on the moving direction of the mark 92 in the shooting field of view 90 when the XY stage 20 is moved along the Y direction. You may.

As described above, according to the imaging system 1 according to the embodiment of the disclosed technique, the specific unit 82 places the mark 92 arranged at a predetermined position on the XY stage 20 within the imaging field of view of the first microscope unit 10A. The imaging field of view of the first microscope unit 10A and the imaging field of the second microscope unit are based on the amount of movement of the XY stage 20 in the X and Y directions when the microscope unit 10B is moved into the imaging field of view. The positional relationship of the shooting field of view of 10B is specified. Since the positional relationship of the shooting field of view is specified based on the amount of movement of the XY stage 20 when the mark 92 is moved between the shooting fields of the first and second microscope units 10A and 10B, the positional relationship of the shooting field of view is specified. Can be specified with high accuracy (micron order). This makes it possible to appropriately join the images taken by each of the first and second microscope units 10A and 10B.

Further, according to the photographing system 1 according to the embodiment of the disclosed technique, the correction unit 83 responds to the inclination of the photographing field of view of each of the microscope units with respect to the images acquired by the first and second microscope units 10A and 10B. Since the rotation correction is performed, it is possible to appropriately join the images even when the shooting field of view is tilted.

Further, according to the photographing system 1 according to the embodiment of the disclosed technique, each of the first and second microscope units 10A and 10B shares the photographing range and performs parallel operation. As a result, the imaging time can be shortened as compared with the case of using a single microscope unit. Further, the moving distance of the XY stage 20 can be shortened.

Further, according to the photographing system 1 according to the embodiment of the disclosed technique, the arrangement intervals of the first and second microscope units 10A and 10B arranged side by side along the X direction are the nuclear dry plate NP which is the object to be photographed. It is considered to correspond to the value obtained by dividing the length in the X direction by the number of microscope units. As a result, the imaging range shared by each of the first and second microscope units 10A and 10B can be made uniform, so that the moving distance in the X direction in the XY stage 20 can be minimized.

Further, according to the photographing system 1 according to the embodiment of the disclosed technique, the first moving mechanism 31 that integrally moves the focal positions of the first and second microscope units 10A and 10B along the Z direction. It also includes both a second moving mechanism 35 that moves each focal position individually. Thereby, for example, when the focal position is roughly adjusted, the first moving mechanism 31 is operated, and when the focal position is finely adjusted, the second moving mechanism 35 is operated. .. Further, when the imaging system 1 is provided with the second moving mechanism 35, for example, when the nuclear emulsion NP is warped, the focal positions of the first and second microscope units 10A and 10B are set according to the warp. Can be different from each other. As a result, in each of the first and second microscope units 10A and 10B, the movement range of the focal position along the Z direction can be minimized, and the imaging system 1 includes only the first movement mechanism 31. The shooting time can be shortened as compared with.

[Second Embodiment]
The imaging system 1 according to the first embodiment described above includes two microscope units. On the other hand, the imaging system according to the second embodiment includes four microscope units.

FIG. 17 is a plan view showing an example of the positional relationship of the four microscope units included in the imaging system according to the second embodiment of the disclosed technique. The imaging system according to the second embodiment of the disclosed technique includes a first microscope unit 10A, a second microscope unit 10B, a third microscope unit 10C, and a fourth microscope unit 10D.

The second microscope unit 10B is arranged apart from the first microscope unit 10A in the X direction. The third microscope unit 10C is arranged apart from the first microscope unit 10A in the Y direction. The fourth microscope unit 10D is arranged so as to be separated from the second microscope unit 10A in the Y direction and separated from the third microscope unit 10C in the X direction.

The placement interval of the microscope units juxtaposed along the X direction is D1, the placement interval of the microscope units juxtaposed along the Y direction is D2, the length of the nuclear dry plate NP in the X direction is W, and the Y direction of the nuclear dry plate NP. Assuming that the number of microscope units juxtaposed along the L and X directions is n1 and the number of microscope units juxtaposed along the Y direction is n2, the following equations (3) and (4) are used. It is preferable to satisfy.
D1 = W / n1 ... (3)
D2 = L / n2 ... (4)

As a result, the imaging range shared by each of the plurality of microscope units can be made uniform, so that the moving distances in the X direction and the Y direction in the XY stage 20 can be minimized. In the configuration shown in FIG. 17, the number of microscope units juxtaposed along the X direction is two (n1 = 2), and the number of microscope units juxtaposed along the Y direction is two (n2 = 2). Therefore, it is preferable that D1 = W / 2 and D2 = L / 2.

FIG. 18 is a plan view showing a preferable arrangement of the marks 92 when the first to fourth microscope units 10A to 10D are arranged in the manner shown in FIG. As shown in FIG. 18, the mark 92 is a straight line V1 passing through the midpoint of the straight line H1 connecting the optical axes of the first and second microscope units 10A and 10B and orthogonal to the straight line H1, and the first and third lines. It is preferable that the microscope units 10A and 10C are arranged on the intersection Q with the straight line H2 passing through the midpoint of the straight line V2 connecting the optical axes and orthogonal to the straight line V2. By arranging the mark 92 on the intersection Q, the mark 92 can be observed in each of the first to fourth microscope units 10A to 10D by moving the XY stage 20 in the X and Y directions. ..

The number of microscope units provided in the imaging system can be three or five or more. It is also possible to configure the imaging system to include two or more microscope units juxtaposed along the Y direction.

[Third Embodiment]
The photographing system 1 according to the first embodiment described above includes a lighting device 50 provided corresponding to each of the plurality of microscope units included in the photographing system 1. On the other hand, the imaging system according to the third embodiment includes a single illumination device 50 commonly used for each of the plurality of microscope units.

FIG. 19 is a diagram showing an example of the configuration of the lighting device 50A included in the photographing system according to the third embodiment of the disclosed technique. The lighting device 50A includes a strobe light source 51, a condenser lens 52, condenser lenses 55A and 55B, a half mirror 56, and mirrors 57, 58 and 59. In the lighting device 50A, the light from the strobe light source 51 is divided by the half mirror 56. One of the divided lights is irradiated to the imaging position of the first microscope unit 10A as illumination light through the mirrors 58 and 59 and the condenser lens 55A. The other of the divided light is irradiated as illumination light to the imaging position of the second microscope unit 10B through the mirror 57 and the condenser lens 55B.

As described above, the illumination device 50A according to the present embodiment divides the single light source and the light from the light source, and irradiates the illumination light to the respective photographing positions of the first and second microscope units 10A and 10B. It is configured to include an optical system configured to do so. According to the lighting device 50A according to the present embodiment, the number of parts can be reduced as compared with the case where the lighting device is provided for each microscope unit, so that it is possible to realize miniaturization and cost reduction of the device. Become.

1 Imaging system 10A 1st microscope unit 10B 2nd microscope unit 10C 3rd microscope unit 10D 4th microscope unit 11 Microscope 11i Imaging lens 11o Objective lens 12 Imaging device 12A Imaging element 20 XY stage 20S Main surface 21, 22 Motor 23 Holder 24 Glass 31 First moving mechanism 32 Support member 33 Strut 35 Second moving mechanism 40 Detector 50, 50A Lighting device 51 Strobe light source 52 Condensing lens 55, 55A, 55B Condenser lens 56 Half mirror 57, 58, 59 Mirror 60 Information processing device 61 CPU
62 Memory 63 Storage unit 64 Display unit 65 Input unit 66 Network I / F
67 External I / F
68 Bus 71 Imaging control program 72 Positional relationship identification program 73 Image correction program 81 Control unit 82 Specific unit 83 Correction unit 90 Imaging field of view 92 Mark 94 Film NP Nuclear emulsion FB Support EL Track recording layer

Claims (18)

A stage that can move in the first direction and a second direction that is orthogonal to the first direction,
A microscope for acquiring an image of an object to be imaged mounted on the stage and an image acquired by the microscope, which are juxtaposed along at least one of the first direction and the second direction, are photographed. Multiple microscope units equipped with imaging devices
The mark placed at a predetermined position on the stage is moved from the imaging field of view of the first microscope unit of the plurality of microscope units to the imaging field of view of the second microscope unit of the plurality of microscope units. The positional relationship between the imaging field of view of the first microscope unit and the imaging field of view of the second microscope unit is specified based on the amount of movement of the stage in the first direction and the second direction when the stage is moved. With a specific part to do
Shooting system including. The imaging system according to claim 1, wherein the specific unit derives coordinate values in a common coordinate system for images captured by each of the plurality of microscope units based on the specified positional relationship. The specific unit includes the position coordinates of the stage when the mark is located in the field of view of the first microscope unit, and the mark when the mark is located in the field of view of the second microscope unit. The imaging system according to claim 1 or 2, wherein the positional relationship between the imaging field of view of the first microscope unit and the imaging field of view of the second microscope unit is specified based on the position coordinates of the stage. For each of the plurality of microscope units, the tilt angle of the coordinate axes in the photographing field of view with respect to the first direction or the second direction is derived, and the tilt angle of the image taken by each of the plurality of microscope units is described. The imaging system according to any one of claims 1 to 3, further comprising a correction unit that performs rotation correction according to the above. The correction unit is based on the moving direction of the mark arranged on the stage in the imaging field of view of the microscope unit when the stage is moved along the first direction or the second direction. The imaging system according to claim 4, wherein the tilt angle is derived for the microscope unit. The arrangement interval of the plurality of microscope units juxtaposed along the first direction is the length of the object to be imaged in the first direction, and the plurality of microscope units juxtaposed along the first direction. The imaging system according to any one of claims 1 to 5, which corresponds to a value divided by the number of. Claims 1 to 6 further include a moving mechanism that moves the focal position of each of the plurality of microscope units along a third direction orthogonal to both the first direction and the second direction. The photographing system according to any one item. The imaging system according to claim 7, wherein the moving mechanism includes a first moving mechanism that integrally moves the focal position of each of the plurality of microscope units along the third direction. The imaging system according to claim 7 or 8, wherein the moving mechanism includes a second moving mechanism that individually moves the focal position of each of the plurality of microscope units along the third direction. Any one of claims 7 to 9, further including a control unit that controls each of the microscope units to instruct the microscope unit to take an image based on the focal position of the microscope unit in the third direction. The shooting system described in the section. A claim that further includes an illuminating device that irradiates illumination light from a side opposite to each of the plurality of microscope units with the object to be imaged interposed therebetween at each imaging position of the plurality of microscope units of the object to be photographed. The photographing system according to any one of items 1 to 10. The lighting device is
With a single light source
An optical system configured to divide the light from the light source and irradiate the imaging position of each of the plurality of microscope units with the illumination light.
The photographing system according to claim 11, which includes. One of claims 1 to 12, further comprising a detector that is provided corresponding to each of the plurality of microscope units and detects the height of the imaged object at the imaging position of the corresponding microscope unit. The shooting system described. The optical performance of the microscope provided in each of the plurality of microscope units is equivalent.
The imaging system according to any one of claims 1 to 13, wherein the imaging performance of the imaging apparatus included in each of the plurality of microscope units is the same. The plurality of microscope units
The first microscope and
A second microscope arranged apart from the first microscope in the first direction,
A third microscope arranged apart from the first microscope in the second direction,
A fourth microscope arranged apart from the second microscope in the second direction and separated from the third microscope in the first direction.
The photographing system according to any one of claims 1 to 14. A stage movable in a first direction and a second direction orthogonal to the first direction is juxtaposed along at least one of the first direction and the second direction, and each is placed on the stage. By each of the plurality of microscope units of an imaging system including a plurality of microscope units provided with a microscope for acquiring an image of an mounted object to be imaged and an imaging device for capturing an image acquired by the microscope. It is a processing method of the captured image,
The mark placed at a predetermined position on the stage is moved from the imaging field of view of the first microscope unit of the plurality of microscope units to the imaging field of view of the second microscope unit of the plurality of microscope units. The positional relationship between the imaging field of view of the first microscope unit and the imaging field of view of the second microscope unit is specified based on the amount of movement of the stage in the first direction and the second direction when the stage is moved. Image processing methods that include doing. The image processing method according to claim 16, wherein a coordinate value in a common coordinate system is derived for an image taken by each of the plurality of microscope units based on the specified positional relationship. For each of the plurality of microscope units, the tilt angle of the coordinate axes in the captured image with respect to the first direction or the second direction is derived, and the image captured by each of the plurality of microscope units is described. The image processing method according to claim 16 or 17, wherein the rotation is corrected according to the inclination angle.

Images