JP4072420B2 - Calibration method for fluoroscopic inspection apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a non-destructive X-ray fluoroscopic inspection apparatus for inspecting an inside of a subject, and in particular, an X-ray fluoroscopic inspection apparatus and an X-ray fluoroscopic inspection apparatus for irradiating a substrate on which electronic components are mounted with X-rays to inspect the inside. It relates to a calibration method.
[0002]
[Prior art]
An X-ray fluoroscopic inspection apparatus that inspects an internal state of a substrate or the like on which an electronic component is mounted detects an X-ray tube that emits X-rays and X-rays emitted from the X-ray tube with two-dimensional resolution. A subject, which is a substrate on which electronic components are mounted, is placed between the X-ray detector and a transmission image of the subject is obtained.
[0003]
In order to obtain high resolution, this X-ray fluoroscopic examination apparatus uses a microfocus X-ray tube having an X-ray focal point of about several μm, and sufficiently closes a transmission image in a narrow range by bringing the subject close to the X-ray focal point. I try to shoot at a rate. Further, a wide range of transmission images can be obtained by moving the subject away from the X-ray focal point and reducing the magnification.
[0004]
[Patent Document 1]
JP-A-6-331571 [0005]
[Patent Document 2]
JP-A-2000-97881 [0006]
[Patent Document 3]
Japanese Patent Laid-Open No. 2001-255286
[Problems to be solved by the invention]
In such a conventional X-ray fluoroscopic inspection apparatus, for example, when inspecting a BGA (Ball Grid array) in which an IC (semiconductor integrated circuit) is bonded to a substrate, a large number of them are bonded to the substrate. Of the ICs, predetermined target ICs are sequentially stored in the X-ray field of the X-ray fluoroscopic inspection apparatus, and the stored ICs are magnified to visually inspect the BGA, and there are suspected solder balls in the BGA. In this case, the solder ball is further enlarged and repeatedly inspected, but the field of view must be moved by a manual switch, or from one IC to the next IC, or from one solder ball to the next solder. When moving to the ball, there is a problem that the operation is troublesome because it is necessary to perform a manual switch operation to lower the enlargement ratio once.
[0008]
In other words, when moving to the next IC, the enlargement ratio is once lowered to widen the field of view, the next target IC is moved into the view of the IC, and the enlargement ratio is set so that the entire target IC can be accommodated. Test the IC. Similarly, when moving to the next solder ball, it is necessary to repeat the operation of lowering the enlargement ratio once, placing the next solder ball in the field of view, moving it, and raising the enlargement ratio again.
[0009]
In particular, since it is usually not possible to fit the entire substrate on one transmission image, it is difficult to determine the movement direction or the like when moving beyond the range of one transmission image, and there is a problem that ICs are mistaken.
[0010]
An object of the present invention is to provide an X-ray fluoroscopic inspection apparatus and a method for calibrating the X-ray fluoroscopic inspection apparatus that can easily put a target position of a subject into the field of view of a transmission image.
[0011]
[Means for Solving the Problems]
In order to solve the above-described problems, an invention according to claim 1 is directed to an X-ray source, a two-dimensional X-ray detector that detects X-rays generated from the X-ray source and transmitted through a subject, and the X-rays A display for displaying a transmission image obtained by a detector; and a substantially planar object positioned between the X-ray source and the X-ray detector, and the transmission on the object along the substantially plane. A moving mechanism that relatively moves the field of view of the image;
A movement control means for controlling the movement mechanism, and an enlargement ratio change for changing the size of the field of view by giving a relative movement in the X-ray transmission direction between the X-ray source, the X-ray detector and the subject. The X used in an X-ray fluoroscopic inspection apparatus comprising: means; and an image composition means for forming a composite transmission image from transmission images obtained at a plurality of positions of the movement forming a vertical and horizontal matrix at a predetermined magnification. A method for calibrating a fluoroscopic inspection apparatus, wherein two transmission images are in contact with a calibration plate having a pattern on a transmission image at a predetermined magnification, so that the two transmission images are in contact with each other vertically or horizontally, and the border of the border The unit of movement when moving to the plurality of positions in the vertical or horizontal direction by adjusting the movement position so that the two transparent images are displayed side by side and the pattern is continuously connected is displayed. Seeking The gist.
[0012]
With this configuration, a composite transmission image in a desired range including the whole can be obtained even for a subject that does not fit in the field of view at a predetermined magnification (minimum magnification) . Here, the X-ray source is an X-ray tube that outputs an X-ray beam, and the moving mechanism is an x, y mechanism. The enlargement ratio changing means refers to a z mechanism that can move the subject closer to or away from the X-ray tube.
[0020]
In addition, by this method, it is possible to directly move the movement unit that connects the borders of adjacent transmission images of the composite transmission image and confirm the joint to obtain the movement unit.
[0021]
To achieve the above object, an invention according to claim 2, wherein, in the calibration method of the X-ray fluoroscopy apparatus according to claim 1, 2 which intersect substantially orthogonal to each other at substantially 45 ° to the sides of the pattern is at least the boundary The gist is to include a substantially straight line.
[0022]
By this method, since the pattern intersects with the boundary at 45 °, the movement unit can be accurately obtained in both the vertical and horizontal directions.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments to which the present invention is applied will be described below with reference to the drawings.
[0030]
(First embodiment)
FIG. 1 is a schematic configuration diagram of an X-ray fluoroscopic inspection apparatus according to a first embodiment of the present invention. As shown in FIG. 1, the X-ray fluoroscopic examination apparatus includes an X-ray tube 1 that emits X-rays, an X-ray detector 3 that is disposed opposite to the X-ray tube 1, an X-ray tube 1 and X-ray detection. A planar table 5 arranged perpendicular to the arrangement direction of the container 3; an xy mechanism 6 for moving the table 5 in the plane direction; and z for moving the table 5 in a direction perpendicular to the plane direction. The mechanism 7, the xy mechanism 6, the z mechanism 7, and the like are controlled, and a data processing unit 8 that processes a transmission image captured by the X-ray detector 3 and an image processed by the data processing unit 8 are displayed. And at least a display unit 9.
[0031]
The X-ray tube 1 and the X-ray detector 3 are each supported by a floor and arranged so that the X-ray beam 2 generated from the X-ray focal point F is detected by the X-ray detector 3 having a two-dimensional resolution. ing. Here, a microfocus X-ray tube having an X-ray focal point F of several μm is used as the X-ray tube 1. The X-ray detector 3 has an X-ray I.D. A combination of I and a TV camera is used, or an X-ray flat panel sensor is used. The transmission image detected by the X-ray detector 3 is sent to the data processing unit 8 and converted into a digital image for image processing. The processed image or the unprocessed live image (real-time transmission image) is displayed on the display unit 9.
[0032]
The subject 4 (substrate) is placed on the table 5 and positioned in the X-ray beam 2. This positioning is controlled by an xy mechanism 6 and a z mechanism 7 provided in the table 5.
[0033]
The xy mechanism 6 has a function of moving the table 5 along the table surface and moving the subject 4 with respect to the visual field 14 of the transmission image.
[0034]
The z mechanism 7 has a function of moving the table 5 and the xy mechanism 6 in the radiation direction of the X-ray beam 2 (up and down in FIG. 1) and changing the imaging magnification (magnification rate) of the subject 4. is doing.
[0035]
The data processing unit 8 and the display unit 9 are computers including a normal display. The data processing unit 8 and the display unit 9 are composed of a CPU, a memory, a disk, an interface, a keyboard, a mouse, and the like and store various software.
[0036]
The operator issues a command to the data processing unit 8 and the display unit 9 via an input means (not shown) to set X-ray conditions, turn on / off the X-ray, manually operate the mechanism unit, observe and record a transmission image. And image processing. Specifically, the xy mechanism 6 and the z mechanism 7 are controlled by a mechanism control unit (not shown) according to a command from the data processing unit 8, and the X-ray tube 1 is controlled by an X-ray control unit (not shown) according to the command. Tube voltage, tube current, and X-ray ON / OFF are controlled.
[0037]
The data processing unit 8 includes a composition range input unit 10, an image composition unit 11, a position designation unit 12, a movement control unit 13 and the like as software function blocks.
[0038]
Next, the operation of the X-ray fluoroscopic inspection apparatus according to the first embodiment will be described.
[0039]
As a general action of the transmission image photographing, first, the subject 4 is placed on the table 5, and then the X-ray beam 2 starts to be emitted, and the transmission of the subject 4 projected through the subject 4 is transmitted. The image is detected by the X-ray detector 3 and transmitted to the data processing unit 8. The data processing unit 8 converts the detected transmission image into a digital image, and displays a live image (real-time transmission image) or a processed image on the display unit 9.
[0040]
In this transmission image capturing, “composite image creation” is first performed for one subject to obtain an entire image of the subject 4, and then “movement and examination” is performed based on this composite image. Detailed defect inspection is performed. Also, before using the X-ray fluoroscopic examination apparatus, the movement unit used at the time of “composite image creation” is obtained by performing “calibration” once.
[0041]
Hereinafter, specific operations will be described in the order of “composite image creation”, “movement and inspection”, and “calibration”. The “composite image creation” is a process performed by the synthesis range input unit 10 and the image synthesis unit 11.
[0042]
FIG. 2 is a diagram illustrating a display example of the composite image creation window displayed on the display unit 9.
[0043]
The operator inputs a display instruction for the composite image creation window to the data processing unit 8 via the input means. Upon receiving the command, the data processing unit 8 displays the composite image creation window shown in FIG. 2 on the display unit 9.
[0044]
The operator inputs the composite range in accordance with the input instruction of the displayed composite image creation window. If “All Area” in the window is selected here, the entire surface of the table 5 is selected. If “Specified Area (Size)” is selected, the vertical size and horizontal size are set to the minimum magnification (= minimum magnification). It is possible to input in integer multiples of vertical and horizontal dimensions. When inputting the vertical dimension and the horizontal dimension, click the triangle mark on the input display unit with a mouse or the like, and change the size value (mm) by jumping to determine. Thus, the vertical and horizontal multiples n × m are determined.
[0045]
Next, when the “start” key is clicked, the synthesis range input unit 10 that has received this start signal causes the subject 4 and the X-ray tube 1 to image the subject 4 at the minimum magnification with respect to the z mechanism 7. Command is issued so that the subject 4 is fully separated, and the subject 4 is automatically set at the minimum magnification. When this setting is completed, the X-ray beam 2 is output from the X-ray tube 1 and a live image of the subject 4 is displayed on the display unit 9.
[0046]
Subsequently, the operator sets the starting point while observing the live image displayed in the live image window of the display unit 9 and moving the subject 4 in the xy direction so that the upper left portion of the subject 4 is just within the visual field 14.
[0047]
In other words, for example, by operating the arrow key of the keyboard, the table 5 moves xy according to the operation amount and the movement state is sequentially displayed on the live screen. Set the start point so that the part fits on the live screen. When the start point setting is completed, a “continue” key (not shown) is clicked to proceed to the next screen.
[0048]
The image composition unit 11 uses the set position as the start point (upper left point), defines the vertical dimension and horizontal dimension of the field of view at the lowest magnification as the respective vertical and horizontal movement units, and sets the movement position as an n × m matrix. The transmission is sequentially performed, and a transmission image is photographed at each position. The photographed transmission images are thinned and reduced, and connected in the vertical and horizontal directions to create a composite transmission image.
[0049]
As the number of thinning-out, if the larger of n and m is the thinning-out number ν, and thinning out so that one is left in both the vertical and horizontal directions, the maximum combined transmission image that does not exceed the original image can be made. You don't have to do this. The composite transmission image created in this way is stored on a storage disk or the like.
[0050]
The movement of “movement and inspection” is a process performed by the position specifying unit 12 and the movement control unit 13.
[0051]
FIG. 3 is a diagram illustrating a display example of the composite image window displayed on the display unit 9.
[0052]
As shown in FIG. 3, a composite transparent image 20, a “history display / non-display” key, a “history clear” key, and a “close” key are displayed in the composite image window.
[0053]
The operator inputs the inspection position on the displayed composite image window. Specifically, the cursor 21 is moved (operating with a mouse or the like) on the combined transparent image 20 to specify a desired position and double-click. As a result, the double-clicked position coordinate is output to the movement control unit 13, and the movement control unit 13 controls the xy mechanism 6 based on the clicked position coordinate so that the specified position is at the center of the field of view 14. Move to come.
[0054]
The operator manually operates the z mechanism 7 at this xy position to select an enlargement ratio, and displays the transmission image in the live image window for inspection. At this time, the composite image window and the live image window may be reduced and displayed in parallel, or the necessary image may be switched to the front by overlapping in front and back. It should be noted that the enlargement ratio change, manual movement of the visual field 14, and X-ray condition change are performed from another manual operation window, a keyboard, or a separate operation panel.
[0055]
Next, returning to the composite image window, a position to be focused next is specified and double-clicked. Then, the image automatically moves to the designated position with the same enlargement ratio, so that the transparent image at this position automatically appears in the live image window. In this way, it is possible to inspect one after another simply by specifying the position on the combined transmission image 20.
[0056]
On the synthesized transparent image 20, the history of the designated position and the current position are displayed by, for example, a + mark or a square mark. The history display can be switched to non-display, and the history can be cleared. The synthesized transmission image 20 is stored on a storage disk including a history and can be used as a test record.
[0057]
“Calibration” is a process performed once before using the X-ray fluoroscopic examination apparatus. Although it is performed mainly at the time of manufacturing the X-ray fluoroscopic inspection apparatus, after repair / adjustment affecting X-ray optics, or when the thickness of the subject 4 changes, it may be performed periodically. The “calibration” is performed by a calibration unit (not shown) in the data processing unit 8.
[0058]
In this calibration, the vertical and horizontal movement units, that is, the vertical and horizontal dimensions of the field of view at the lowest magnification are obtained and stored.
[0059]
FIG. 4 is a diagram illustrating an example of a calibration plate used for calibration. The calibration plate 24 is obtained by attaching thin copper plates 26 and 27 on a base plate 25 made of a material such as plastic. The copper plates 26 and 27 are cut into right-angled isosceles triangles, and two equal sides of the triangular copper plates 26 and 27 are bonded to the base plate 25 at an angle of about 45 °. The thickness of the base plate 25 is set such that the height of the copper plates 26 and 27 becomes substantially the same as the average inspection surface height of the subject 4 when placed on the table 5.
[0060]
Next, a calibration method using the calibration plate 24 will be described.
[0061]
First, in order to obtain the horizontal movement unit, the operator places the calibration plate 24 on the table 5 and opens the horizontal calibration window.
[0062]
FIG. 5 is a diagram illustrating an example of a display of the horizontal calibration window displayed on the display unit 9. As shown in FIG. 5, the horizontal calibration window includes a first image 28 and a second image 29, a “start” key, a “first image set” key, a “second image set” key, and a “close”. The key is displayed.
[0063]
The operator clicks the “start” key in the displayed window. Then, the image processing unit 8 that has received this start signal issues a command to the z mechanism 7 so that the calibration plate 24 and the X-ray tube 1 are separated as much as possible so that the subject 4 is imaged at the minimum magnification. As a result, the calibration plate 24 is automatically set at the minimum magnification. When this setting is completed, the X-ray beam 2 is output from the X-ray tube 1, and a live image of the calibration plate 24 is displayed on the first image 28.
[0064]
Next, the operator moves the xy so that the two sides of the copper plate 27a of the calibration plate 24 cross the right edge of the screen while observing the first image 28 (live image). Click the key. Then, the first image 28 is fixed, and the live image is displayed on the second image 29.
[0065]
That is, when the “first image set” key is clicked, the update of the first image 28 is stopped at that moment, and the still image is displayed as it is on the first image 28. On the other hand, the live image moves to the second image 29 and continues to be displayed as it is.
[0066]
Next, the operator moves the xy so that two sides of the copper plate (image) 27 b displayed in the second image 29 are connected to the first image 28.
[0067]
That is, for example, by operating an arrow key of the keyboard, the table 5 controlled according to the operation amount is moved in the xy direction, and the two sides of the copper plate 27b are the first image while checking the moving state on the live screen. Adjust so that it is connected to 28.
[0068]
FIG. 6 is a diagram illustrating an xy movement method for connecting the second image 29 to the first image 28. First, when the images displayed in the first image 28 and the second image 29 are shifted as shown in FIG. 6A, they are moved only in the x direction, and then shifted as shown in FIG. 6B. If it is, move it only in the y direction, and match the contour of the copper plate 27a of the first image 28 and the contour of the copper plate 27b of the second image 29 at the boundary of the image as shown in FIG. 6 (c). To complete the move.
[0069]
In this state, the “second image set” key is clicked. As a result, the second image 29 is fixed, and the movement amount between the first image 28 and the second image 29 is calculated by the data processing unit 8 based on (Equation 1) as a horizontal movement unit. Is stored in the memory.
[0070]
[Expression 1]
Horizontal movement unit (vector) = (x2-x1, y2-y1) (1)
Here, x1, y1 and x2, y2 indicate the movement positions of the first image 28 and the second image 29, respectively. That is, the horizontal direction of the image is roughly aligned with the x direction, but there is a slight error. The y component in equation (1) corresponds to this slight error correction.
[0071]
The vertical movement unit is also obtained in the same manner, but since it can be easily guessed, the description is omitted and only the formula is described.
[0072]
[Expression 2]
Vertical movement unit (vector) = (x4−x3, y4−y3) (2)
Here, the lower side of the third image is the fourth image, the boundaries of the transmission images are aligned, and the respective movement positions are x3, y3 and x4, y4.
[0073]
Therefore, according to the X-ray fluoroscopy apparatus according to the first embodiment of the present invention having such a configuration, the target position of the subject 4 can be easily put in the visual field 14 of the transmission image.
[0074]
In “composite image creation”, since the designated area is selected by changing the display of the designated area size value (mm) in a jumping manner, a vertical and horizontal multiple n × m exceeding the desired range can be easily selected.
[0075]
Furthermore, since the start point position can be set while confirming the transparent image (for example, the upper left end of the desired range is at the upper left end of the transparent image), the desired range can be set reliably.
[0076]
Further, since the image capturing is performed by inputting the start point and the vertical and horizontal multiples n and m, and the image composition is made by simple thinning composition, the data processing unit 8 can easily perform the image composition.
[0077]
In “movement and inspection”, the entire image (in the desired range) of the subject can be seen with the composite transmission image 20 exceeding the maximum visual field, and it is easy to reach this position by simply specifying the position on the composite transmission image 20. Thus, the visual field 14 can be moved and further detailed observation can be performed.
[0078]
Further, even if observation is performed with the enlargement factor increased at the movement destination, it is possible to move to that position with the same enlargement factor simply by designating the next position on the composite transmission image 20.
[0079]
Furthermore, since the observation image (live image) and the composite transmission image 20 are separate windows, it is easy to switch and change the arrangement of the images.
[0080]
Furthermore, since the history of the specified position and the current position are displayed on the composite transparent image 20, it is possible to know at a glance which position was inspected, and to know the inspected position, the current position, and the next inspection position even during the inspection. This makes it difficult to cause forgotten inspection positions and duplicate inspection positions.
[0081]
There is also an advantage that the history can be recorded as a record. Furthermore, since the history can be switched between display and non-display, when the history is dense and the composite transparent image 20 is difficult to see, it can be hidden.
[0082]
You can also clear the history when you want to redo the inspection.
[0083]
In “calibration”, since the unit of movement is obtained by moving the transmission images so that the transmission images at the boundary between the two adjacent images are connected, the combined transmission image 20 with good connection can be created.
[0084]
In addition, even if the vertical and horizontal directions of the image and the xy direction of the mechanism are shifted, the movement unit is obtained based on the vertical and horizontal directions of the image (as vectors of x and y), so that the movement can be adjusted to the vertical and horizontal directions of the image. A well-connected composite transmission image 20 can be created.
[0085]
In addition, even if the x direction and y direction of the mechanism are not orthogonal, since the image is similarly moved with reference to the vertical and horizontal directions of the image, a combined transmission image 20 with good connection can be created.
[0086]
Furthermore, since the movement unit is obtained so that two lines of substantially straight lines that intersect the boundary line at approximately 45 ° and are substantially orthogonal to each other at the boundary of the two images are connected, the xy direction accuracy of the movement unit is uniform. Thus, both the xy directions can be obtained with high accuracy, and this makes it possible to create a combined transmission image 20 with good connection.
[0087]
(Modification of the first embodiment)
The first embodiment includes many parts that are not essential to the gist of the present invention. Each content will be described below.
[0088]
<Relativity of movement>
The enlargement ratio is changed by moving the subject 4 in the direction along the X-ray beam 2, but this is not essential in the present invention. For example, the X-ray tube 1 or the X-ray detector 3 is moved. You may do it. Further, the xy movement of the visual field 14 may be equivalent to the movement of the X-ray tube 1 and the X-ray detector 3 instead of moving the subject 4.
[0089]
<Input format of composition range>
In the composition range, teaching input is used for the starting point and numerical values are input for the vertical and horizontal dimensions, but this is not essential, and the starting point may be input as numerical values, or both the starting point and end point may be input as teaching. When teaching the end point (lower right point), the end point is selected by jumping from the start point by a predetermined movement unit.
[0090]
The composite range to be input may not be an integral multiple of the size of one field of view. In this case, an integer multiple range that includes the input synthesis range is synthesized. The xy movement control sequentially moves to a movement position that forms a matrix in the vertical and horizontal directions in a predetermined movement unit, and captures a transmission image at each position and exceeds the combined range input in the vertical and horizontal directions. A transmission image is taken in such a way that the movement is canceled.
[0091]
<Automatic setting of composition range>
A range in which the entire subject 4 is accommodated can be automatically detected as a synthesis range. At this time, the subject 4 is assumed to be rectangular. Therefore, the operator manually moves the subject 4 to the position where the subject 4 surely enters the visual field in the xy direction to start the composite image creation. As a result, the image synthesizing unit 11 captures an image at a matrix position of a predetermined unit of movement in the vertical and horizontal directions starting from this position. First, the image synthesis unit 11 proceeds to the left to capture an image and process the transmitted image to process the edge of the subject. Is detected and this position is set as the left limit. Then, it returns to the starting point, and then proceeds to the right, and the right limit is obtained in the same manner. Similarly, the upper limit is determined from the starting point, and the lower limit is determined by further proceeding downward. Next, a transmission image is photographed at the remaining position of the matrix position limited by each limit, and each transmission image is synthesized to create a combined transmission image. For detection of the edge of the subject 4, an image without the subject 4 is stored in advance, and this is compared with the captured image to determine whether or not there is a region without the subject 4. To do.
[0092]
In the above-described automatic setting of the composition range, the composition range is determined using the image while photographing the composition transmission image. However, the present invention is not limited to this. After the range is determined, a composite transmission image may be taken for the range.
[0093]
Further, the automatic setting of the synthesis range can be performed even when the subject 4 is indefinite, for example, by a method of moving along the edge while searching for the edge.
[0094]
From the above, it is possible to eliminate the need to input the synthesis range by automatically setting the synthesis range.
[0095]
<Image composition>
It is not always necessary to create a composite image at the minimum magnification. That is, it is possible if the magnification is determined in advance and the movement unit is calibrated.
[0096]
In addition, it is not always necessary to use the entire surface of one photographed transmission image for creating a composite image, and a cut-and-paste visual field in which the edge portion (poor image quality) is discarded may be used. In this case, the “vertical dimension and horizontal dimension of the field of view at the minimum magnification (units of movement in the vertical and horizontal directions)” in this embodiment refers to the dimensions of the visual field for cutting and pasting.
[0097]
On the other hand, the composite image is reduced by thinning, but may be reduced by addition averaging.
[0098]
In addition, although the composite image is thinned and reduced, it may be connected vertically and horizontally without thinning. In this case, everything will not fit in the window, but you can scroll to see it.
[0099]
Furthermore, if the original image that created the composite image is stored, a partially enlarged image of the composite image can be created and displayed without degrading the image quality. It is also possible to specify the position on this partially enlarged image.
[0100]
In addition, a lattice figure such as graph paper can be simply used in place of the synthesized transparent image 20. Thereby, photographing can be omitted. This can be used effectively when the subject (substrate) 4 has vertical and horizontal dimension lines in advance.
[0101]
Further, when there is a design drawing of the subject 4 in a format that can be input to the data processing device 8, it can be used in place of the synthetic transmission image 20, and the same effect can be obtained.
[0102]
If there is a photograph taken from directly above the subject 4 in a format that can be input to the data processing device 8, and if the dimensions per pixel are known, this can be used in place of the composite transmission image 20, and similar effects can be obtained. Can give.
[0103]
<History>
As the history, not only the designated position but also movement by manual operation after moving to the designated position (for example, as a trajectory) can be included in the history. When moving by roughly specifying the position and finely performing the manual operation, the history is accurate. In addition, it is possible to leave a history such that the locus of the visual field range is semitransparently painted or colored on the surface.
[0104]
<Additional functions>
This embodiment can give various additional operations. For example, when the position is designated on the synthetic transparent image 20, the enlargement ratio can also be designated. In addition, the position and the enlargement ratio can be specified at the same time using a rectangular figure. In this case, the xy position and the enlargement ratio are automatically set so that this quadrangle fits in the field of view.
[0105]
An oblique perspective function can also be added. For example, a mechanism for tilting the X-ray detector 3 (and the X-ray tube 1) so that the X-ray beam 2 is obliquely incident on the surface of the subject 4, and a subject for changing the tilt direction are within the plane. Add a rotating mechanism to rotate. In this case, the composite image is created without tilting and rotation, and all the visual field shifts from the specified position caused by tilting and rotation are calculated and corrected during inspection. As a result, the designated position can be put in the field of view even if the position is designated on the combined transmission image, even if tilting / rotation is performed.
[0106]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the calibration method of the X-ray fluoroscope inspection apparatus and X-ray fluoroscope inspection apparatus which can put the target position of a subject into the visual field of a transmission image easily can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram of an X-ray fluoroscopic inspection apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram showing an example display of a composite image creation window.
FIG. 3 is a diagram illustrating a display example of a composite image window.
FIG. 4 is a diagram illustrating an example of a calibration plate.
FIG. 5 is a diagram illustrating an example of a display of a horizontal calibration window.
FIG. 6 is a specific diagram of a method of moving the second image in the xy direction to match the first image.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 X-ray tube 2 X-ray beam 3 X-ray detector 4 Subject 5 Table 6 xy mechanism 7 z mechanism 8 Data processing part 9 Display part 10 Composition range input part 11 Image composition part 12 Position designation part 13 Movement control part 20 Composition Transmission image 21 Cursor 24 Calibration plate 25 Base plates 26 and 27 Copper plate 28 First image 29 Second image

Claims (2)

An X-ray source and a two-dimensional X-ray detector that detects X-rays generated from the X-ray source and transmitted through the subject;
A display unit for displaying the transmitted image obtained by the X-ray detector,
A moving mechanism that positions a substantially planar object between the X-ray source and the X-ray detector and relatively moves the field of view of the transmission image on the object along the substantially plane;
Movement control means for controlling the movement mechanism;
An enlargement ratio changing means for changing the size of the field of view by giving a relative movement in the X-ray transmission direction between the X-ray source, the X-ray detector, and the subject;
The X-ray fluoroscopic inspection used in the X-ray fluoroscopic inspection apparatus, comprising: image combining means for forming a single combined transmission image from the transmission images obtained at a plurality of positions of the movement forming a vertical and horizontal matrix at a predetermined enlargement ratio; A method for calibrating a device, comprising:
At the predetermined magnification, the calibration plate having a pattern on the transmission image is photographed so that the two transmission images are in contact with each other vertically or horizontally, and the pattern intersects with the border of the contact, The X-ray fluoroscopic examination, wherein two transmission images are displayed side by side, and a movement unit is obtained by adjusting a movement position so that the pattern is continuously connected, to move to the plurality of vertical or horizontal positions. Device calibration method. The pattern is a calibration method for X-ray fluoroscopy apparatus according to claim 1 comprising two substantially straight lines which intersect substantially orthogonal to each other at substantially 45 ° to at least the boundary edges.

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