JP5950100B2 - X-ray inspection equipment - Google Patents

Description

  The present invention relates to an X-ray inspection apparatus, and in particular, using an X-ray fluoroscopic image obtained by irradiating an inspection object such as various industrial products with X-rays, the presence or absence of defects inside the inspection object is nondestructive. The present invention relates to an X-ray inspection apparatus that performs inspection.

  In an X-ray inspection apparatus that inspects the presence or absence of internal defects of various industrial products in a non-destructive manner, in general, there is a stage on which an inspection object is placed between an X-ray generator and an X-ray detector. It has an arranged structure. Usually, the stage is movable in a three-dimensional direction (XYZ direction) including the X-ray optical axis direction (direction connecting the X-ray generator and the X-ray detector, Z direction). The perspective magnification is changed by moving the stage in the X-ray optical axis direction (Z direction), and the center of the visual field can be changed by moving the stage on a plane (XY plane) orthogonal thereto. There is also an apparatus that moves the X-ray generator and the X-ray detector together with the stage instead of the stage.

  In an X-ray inspection apparatus used for inspecting components, solder balls, and the like mounted on a circuit board (inspected object), usually, details on the circuit board are observed through an enlarged perspective. For this reason, it is difficult to determine which position on the circuit board is the part currently being seen through. Therefore, an X-ray fluoroscopic image of the object to be inspected is captured and stored at a relatively low magnification (wide field of view), the X-ray fluoroscopic image is displayed on a display, and the fluoroscopic image is enlarged on the X-ray fluoroscopic image. A technique (center moving function) for automatically displaying the X-ray fluoroscopic image by automatically moving the stage by designating the power position and size (desired region) is known (for example, see Patent Document 1). .

In addition, since the X-ray inspection apparatus used for this type of application employs an apparatus configuration for obtaining a high-magnification X-ray fluoroscopic image, X-rays of the entire region (low magnification) of the inspection object A fluoroscopic image cannot be obtained, and for this reason, there is an optical camera for photographing the entire region of the inspection object on the stage (see, for example, Patent Document 2).
FIG. 4 is a block diagram showing a configuration of an X-ray inspection apparatus provided with an optical camera. FIG. 2 is an example of an image displayed by the X-ray inspection apparatus. A direction connecting the X-ray generator and the X-ray detector is defined as a Z direction, a direction perpendicular to the Z direction is defined as an X direction, and a direction perpendicular to the Z direction and the X direction is defined as a Y direction.

  The X-ray inspection apparatus 110 includes a stage 3 on which the inspection object W is placed, a moving mechanism 4 that moves the stage 3 in the XYZ directions, an X-ray generation apparatus 1, an X-ray detector 2, and an inspection object. An optical camera 5 for capturing an appearance image of the entire area of W and a control system 120 for controlling the entire X-ray inspection apparatus 1 are provided. The control system 120 is constituted by a general-purpose computer device. The hardware of the control system 120 is described as a block. The control system 120 is constituted by a CPU 121, an input device 22 such as a keyboard and a mouse, a display 23 such as a liquid crystal panel, and a memory 124. Is done.

  Further, the function processed by the CPU 121 will be described as a block. An X-ray fluoroscopic image acquisition unit 21 a that acquires an X-ray fluoroscopic image from the X-ray detector 2 and displays it on the display 23, and an external image from the optical camera 5. It has an appearance image display control unit 121b that acquires and displays it on the display 23, and a movement mechanism control unit 121c that drives the movement mechanism 4.

According to such an X-ray inspection apparatus 110, as shown in FIG. 2, on the display device 23, the currently viewed X-ray fluoroscopic image T is displayed in the right region, and the appearance image is displayed in the left region. C will be displayed.
Then, the operator uses the appearance image C obtained by photographing the inspection object W from the optical camera 5 in the same direction as the X-ray fluoroscopic direction (−Z direction) like a map, and on the appearance image C every moment. The stage 3 is automatically moved to display the X-ray fluoroscopic image T by superimposing the fluoroscopic position or designating the position to be enlarged and displayed on the external image C by the input device 22 (external navigation). function).

JP 2001-255286 A JP 2006-343193 A

However, in X-ray inspecting apparatus 110 described above, when the height h was examined high object to be inspected W _1, it was the appearance navigation function does not work well. Further, there has been the inability to obtain the appearance image C of the entire region of the object W _1.

Therefore, the applicant examined the cause of the malfunction of the appearance navigation function. In the X-ray inspection apparatus 110, after placing the inspection object W on the stage 3, the stage 3 moves to a predetermined position (X ₀ , Y ₀ , Z ₀ ), and the optical camera 5 captures the appearance image C. It will be. In general, X-ray inspection apparatus 110, it is often to inspect the inspection object W ₂ relatively height h is low such as a circuit board. Therefore, the predetermined positions (X ₀ , Y ₀ , Z ₀ ) for the optical camera 5 to capture the appearance image C are set based on the inspection object W ₂ having a low height h.

Here, FIG. 5A is a diagram when the appearance image C is taken when the inspection object W ₂ having a low height h ₂ is arranged at a predetermined position (X ₀ , Y ₀ , Z ₀ ). FIG. 5B is a view when the appearance image C is taken when the inspection object W ₁ having a high height h ₁ is arranged at a predetermined position (X ₀ , Y ₀ , Z ₀ ). It is.
When the appearance image C of the inspection object W ₁ having a high height h ₁ is taken, the entire area of the inspection object W ₁ is not reflected.
If a predetermined position (X ′, Y ′, Z ′) is set so that the entire area of the inspection object W ₁ having a high height h ₁ is reflected, the appearance of the inspection object W ₂ having a low height h ₂ is displayed. when photographing an image C is would be the size of the entire region of the object W ₂ becomes small, it becomes difficult to specify the position of appearance image C.

FIG. 6A is a diagram when an X-ray fluoroscopic image T is acquired when the inspection object W ₂ having a low height h ₂ is arranged at a position (X ₁ , Y ₁ , Z ₁ ). FIG. 6B shows a case where an X-ray fluoroscopic image T is acquired when the inspection object W ₁ having a high height h ₁ is arranged at a position (X ₁ , Y ₁ , Z ₁ ). FIG.
In the X-ray fluoroscopic image T, in order to calculate the distances x ₁ and x ₂ for moving the desired observation position in the inspection object W to the center of the X-ray fluoroscopic image T, the position of the position (asterisk) to be observed is calculated. It is necessary to know the heights h ₁ and h ₂ from the stage 3 surface. Therefore, when acquiring the fluoroscopic image T, there are those in which the heights h ₁ and h ₂ from the stage 3 surface of the position (star) to be observed are input.

However, when the appearance navigation function using the appearance image C is used, when the desired observation position in the inspection object W is moved to the center of the X-ray fluoroscopic image T, the height h ₁ from the upper surface of the stage 3, h ₂ has not been taken into consideration at all.
Therefore, it has been found that the position (X, Y, Z) of the stage 3 for the optical camera 5 to capture the appearance image C is adjusted by the heights h ₁ and h _{2 of the} inspection object W.

That is, an X-ray inspection apparatus according to the present invention is provided between an X-ray generator and an X-ray detector that are arranged to face each other, and a stage on which an object to be inspected is placed; A moving mechanism for moving in at least three axial directions including a direction, an X-ray fluoroscopic image acquisition unit for acquiring an X-ray fluoroscopic image of a partial area of the inspection object, and an appearance image of the entire area of the inspection object as X An optical camera for photographing from the direction of the linear optical axis, an appearance image display control unit for displaying the appearance image on a display, and a desired position on the appearance image are designated, thereby including the desired position. An X-ray inspection apparatus comprising: a movement mechanism control unit that drives the movement mechanism in two axial directions other than the X-ray optical axis direction so that an X-ray fluoroscopic image is acquired, and the height of the inspection object Is input, the appearance image display control unit After the on position is moved by the amount of the height in a direction away an X-ray optical axis direction from the X-ray detector from a predetermined position, the appearance image of the entire region of the inspection object on the optical camera It is characterized by having a photograph taken.

According to the X-ray inspection apparatus of the present invention, first, the height h of the inspection object W is set. As a result, when the appearance image C of the inspection object W ₁ having a high height h ₁ is taken, the appearance image display control unit moves the stage from a predetermined position (X ₀ , Y ₀ , Z ₀ ) to X-rays. After making the position (X ₀ , Y ₀ , Z ₀ -h ₁ ) moved by the height h ₁ in the optical axis direction, the optical camera is caused to take the appearance image C. Thereby, as the entire area of the object W ₁ it is reflected. Conversely, when the appearance image C of the inspection object W ₂ having a low height h ₂ is taken, the appearance image display control unit moves the stage from a predetermined position (X ₀ , Y ₀ , Z ₀ ) with X-rays. After the position (X ₀ , Y ₀ , Z ₀ -h ₂ ) moved by the height h ₂ in the optical axis direction, the external image C is photographed by the optical camera. Thus, it is no longer the size of the entire region of the object W ₂ is reduced. That is, the position (X, Y, Z) of the stage where the appearance image C is photographed according to the height h of the inspection object W is set to an appropriate position.
Further, since the height h of the surface of the inspection object W shown in the appearance image C from the stage is known, the fluoroscopic position to be enlarged and displayed on the appearance image (the surface of the inspection object W) C is designated. Thus, even when the stage is moved, the distances x and y to be moved can be accurately calculated. That is, the appearance navigation function works well.

  As described above, according to the X-ray inspection apparatus of the present invention, the appearance image C of the entire region of the inspection object W can be taken even with the inspection object W having various heights h. Furthermore, the appearance navigation function works well.

The block diagram which shows the structure of the X-ray inspection apparatus which is one Embodiment of this invention. An example of the image displayed by an X-ray inspection apparatus. The figure when image | photographing an external appearance image. The block diagram which shows the structure of the X-ray inspection apparatus provided with the optical camera. The figure when image | photographing an external appearance image. The figure when acquiring a fluoroscopic image.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments described below, and includes various modes without departing from the spirit of the present invention.

FIG. 1 is a block diagram showing a configuration of an X-ray inspection apparatus according to an embodiment of the present invention. In addition, the same code | symbol is attached | subjected about the thing similar to X-ray inspection apparatus 110.
The X-ray inspection apparatus 10 includes a stage 3 on which an inspection object W is placed, a moving mechanism 4 that moves the stage 3 in the XYZ directions, an X-ray generation apparatus 1, an X-ray detector 2, and an inspection object. An optical camera 5 for capturing an appearance image of the entire region of W and a control system 20 for controlling the entire X-ray inspection apparatus 1 are provided.

The X-ray generator 1 generates cone-beam-shaped X-rays vertically upward (Z direction), and a two-dimensional (XY plane) X-ray detector 2 is disposed above the X-ray generator 1. Opposed.
The stage 3 is disposed between the X-ray generator 1 and the X-ray detector 2, and the inspection object W is placed on the upper surface. Thereby, the X-rays generated from the X-ray generator 1 are detected by passing through the inspection object W on the stage 3 and entering the X-ray detector 2, and the detection output (X-ray fluoroscopic image T) is The information is sent to the control system 20 in real time (predetermined time interval) and displayed on the display 23.

  The stage 3 is movable in a total of three axial directions including the X direction, the Y direction, and the Z direction. As a result, the center of the visual field is adjusted by moving the stage 3 in the X and Y directions, and the measurement magnification is adjusted by moving the stage 3 in the Z direction. The stage 3 may incorporate a rotation mechanism for rotating the sample around the Z axis, other drive shafts, and the like.

  The optical camera 5 is for photographing the entire area of the inspection object W on the stage 3 from the −Z direction, and is disposed adjacent to the X-ray detector 2 above the stage 3 (Z direction). ing. An imaging output (appearance image C) from the optical camera 5 is sent to the control system 20 at a predetermined imaging timing, stored in the memory 24, and displayed on the display 23.

The control system 20 is composed of a general-purpose computer device. The hardware of the control system 20 is described as a block. The control system 20 is composed of a CPU 21, an input device 22 such as a keyboard and a mouse, a display 23 such as a liquid crystal panel, and a memory 24. Is done.
As shown in FIG. 2, the display 23 displays the currently viewed X-ray fluoroscopic image T in the right region and the appearance image C in the left region.

  The input device 22 allows the operator to input the height h of the inspection object W, cause the optical camera 5 to take an appearance image C, or move the stage 3 in the XYZ directions while observing the X-ray fluoroscopic image T. Or the position and size (desired region) to be magnified on the X-ray fluoroscopic image T displayed on the display 23, or the magnified fluoroscopic image C on the appearance image C displayed on the display 23. An operation for designating a power position (desired position) is performed.

Here, the functions processed by the CPU 21 will be described as a block. The X-ray fluoroscopic image acquisition unit 21 a that acquires the X-ray fluoroscopic image T from the X-ray detector 2 and displays it on the display 23, and the optical camera 5 It has an appearance image display control unit 21b that acquires the image C and displays it on the display 23, and a moving mechanism control unit 21c that drives the moving mechanism 4. Further, the memory 24 stores a predetermined position storage area 24a in which predetermined positions (X ₀ , Y ₀ , Z ₀ ) of the stage 3 are stored in advance, and a height for storing the height h of the inspection object W. A storage area 24b is formed.

  The X-ray fluoroscopic image acquisition unit 21 a acquires the X-ray fluoroscopic image T of a partial area of the inspection object W from the X-ray detector 2 and displays the X-ray fluoroscopic image T in the right area of the display 23 in real time. Control. As a result, the operator observes the X-ray fluoroscopic image T and inspects the presence or absence of defects inside the inspection object W.

When the appearance image display control unit 21b receives the input signal “appearance image photographing” from the input device 22, the appearance image display control unit 21b is based on the height h of the inspection object W set in the height storage area 24b. Then, the appearance image C is acquired from the optical camera 5 and the appearance image C is controlled to be displayed in the left region of the display 23. FIG. 3A is a view when the appearance image C is taken when the inspection object W ₂ having a low height h ₂ is arranged at the position (X ₀ , Y ₀ , Z ₀ -h ₂ ). FIG. 3B is a diagram when the appearance image C is taken when the inspection object W ₁ having a high height h ₁ is arranged at the position (X ₀ , Y ₀ , Z ₀ −h ₁ ). is there.

Operator when photographing the height h ₁ is high appearance image of the object W ₁ is set in advance the height h ₁ of the object W to height storage area 24b. Then, the operator inputs an input signal “appearance image photographing” with the input device 22. Then, the appearance image display control unit 21b moves the stage 3 downward (X ₀ , Y ₀ , Z ₀ ) from the predetermined position (X ₀ , Y ₀ , Z ₀ ) by the height h ₁ (X ₀ , Y ₀ , Z _0). −h ₁ ), the optical camera 5 is caused to take an appearance image C (see FIG. 3B). Thus, the entire region of the object W ₁ is reflected.

Further, the operator, when photographing the height h ₂ is the appearance image of the lower inspection object W ₂ is set in advance the height h ₂ of the object W to height storage area 24b. Then, the operator inputs an input signal “appearance image photographing” with the input device 22. Then, the appearance image display control unit 21b moves the stage 3 downward from the predetermined position (X ₀ , Y ₀ , Z ₀ ) by the height h ₂ (X ₀ , Y ₀ , Z _0). -H ₂ ), the optical camera 5 is caused to take an appearance image (see FIG. 3A). Thus, it is no longer the size of the entire region of the object W ₂ is reduced.

The movement mechanism control unit 21c acquires the X-ray fluoroscopic image T of the desired area by designating the desired area on the X-ray fluoroscopic image T displayed on the display device 23 using the input device 22. In this way, control for moving the stage 3 in the XYZ directions is performed (center movement function).
Further, the moving mechanism control unit 21c designates a desired position on the appearance image C displayed on the display device 23 by using the input device 22, whereby an X-ray fluoroscopic image T centered on the desired position is displayed. As acquired, the stage 3 is controlled to move in the XY direction (appearance navigation function). At this time, since the height h from the stage 3 of the surface of the inspection object W shown in the appearance image C is set in the height storage area 24b, the movement mechanism control unit 21c designates the appearance image C on the appearance image C. The distance x and y for acquiring the X-ray fluoroscopic image T centered on the desired position is calculated using the height h, and the stage 3 is moved. Thereby, the appearance navigation function works well.

  As described above, according to the X-ray inspection apparatus 10 of the present invention, the appearance image C of the entire region of the inspection object W can be taken even with the inspection object W having various heights h. Furthermore, since the distances x and y for obtaining the X-ray fluoroscopic image T centered on the desired position designated on the appearance image C are calculated using the height h, the appearance navigation function works well. It becomes like this.

<Other embodiments>
(1) In the X-ray inspection apparatus 1 described above, the height h ₁ of the inspection object W is set in the height storage area 24b before the appearance image C of the inspection object W is taken. However, when inspecting the inspection object W having the same height h ₁ one after another, the step of setting the height h ₁ of the inspection object W in the height storage area 24b may be omitted.

(2) In the X-ray inspection apparatus 1 described above, when the raising jig is used, the height h ₁ of the inspection object W and the height h ′ of the raising jig are stored in the height storage area 24b. It may be configured to be set.

  The present invention uses an X-ray fluoroscopic image obtained by irradiating an inspection object such as various industrial products with X-rays, and inspects the presence or absence of a defect inside the inspection object based on non-destructive inspection. It can be used for devices.

1: X-ray generator 2: X-ray detector 3: Stage 4: Movement mechanism 5: Optical camera 10: X-ray inspection apparatus 21a: X-ray fluoroscopic image acquisition unit 21b: Appearance image display control unit 21c: Movement mechanism control unit 22: Input device 23: Display 24: Memory

Claims (1)

A stage provided between the X-ray generator and the X-ray detector arranged opposite to each other;
A moving mechanism for moving the stage in at least three axial directions including the X-ray optical axis direction;
An X-ray fluoroscopic image acquisition unit for acquiring an X-ray fluoroscopic image of a partial region of the inspection object;
An optical camera for photographing an appearance image of the entire area of the inspection object from the X-ray optical axis direction;
An appearance image display control unit for displaying the appearance image on a display;
A movement for driving the moving mechanism in a biaxial direction other than the X-ray optical axis direction so that an X-ray fluoroscopic image including the desired position is acquired by designating a desired position on the appearance image. An X-ray inspection apparatus comprising a mechanism control unit,
By inputting the height of the object to be inspected, the appearance image display control unit sets the height of the stage in the X-ray optical axis direction from a predetermined position and away from the X-ray detector. An X-ray inspection apparatus, wherein the optical camera is caused to take an appearance image of the entire area of the inspection object after the position is moved by an amount corresponding to the movement amount.