KR101352061B1 - X-ray position measuring apparatus, position measuring method of x-ray position measuring apparatus and position measuring program of x-ray position measuring apparatus - Google Patents

Abstract

Provided is an X-ray position measuring device that realizes high position measuring accuracy without increasing the cost. The X-ray position measuring device 10 includes an image of the first moving means for moving the X-ray radiator 10a and the X-ray camera 10b to a position where position measurement is performed on the measurement object, and at the position for position measurement. First measurement storage means for measuring a position shift amount between the reference position on the display unit and the position on the second X-ray projection image, and storing the position shift amount as a correction amount corresponding to the measurement position; 2nd moving means which moves the line radiator 10a and the X-ray camera 10b to the position which performs position measurement, and the radiation center of the X-ray radiator 10a based on the correction amount in the position which performs position measurement. And first position measuring means for making the optical axis L of the X-ray camera 10b coincide with each other and for performing the position measurement of the measurement object.

Description

X-ray POSITION MEASURING APPARATUS, POSITION MEASURING METHOD OF X-RAY POSITION MEASURING APPARATUS AND POSITION MEASURING PROGRAM OF X -RAY POSITION MEASURING APPARATUS}

The present invention relates to an X-ray position measuring apparatus, a position measuring method of an X-ray position measuring apparatus, and a program for position measuring of an X-ray position measuring apparatus.

Using an X-ray position measuring device equipped with an X-ray radiator and an X-ray camera, the position of the positioning mark provided on each layer constituting the multilayer printed substrate (laminated substrate) is measured, and the exact relative position of each layer is measured. Position measurement to grasp is performed.

In such an X-ray position measuring device, it is necessary for the optical axis of the X-ray radiator to coincide with the X-ray camera in order to accurately measure the position of the positioning mark.

Therefore, conventional X-ray radiators and X-ray cameras are integrated by attaching an X-ray radiator and an X-ray camera to a pair of distal ends of a U-shaped frame to perform optical axis alignment between the X-ray radiator and the X-ray camera. Then, the structure which keeps the state which this optical axis corresponded was employ | adopted (for example, refer patent document 1). In this configuration, the X-ray emitter and the X-ray camera move with respect to the measurement object together with the U-shaped frame.

By adopting such a configuration, it is necessary that the U-shaped frame does not interfere with the multilayer printed board. For this reason, when handling a large multilayer printed circuit board, there existed a situation that a U-shaped frame became large and the whole X-ray position measuring apparatus became large.

On the other hand, the structure which adds an X-ray radiator and an X-ray camera to a track rail with respect to a measurement object independently can mutually be employ | adopted.

JP 2008-227422 A

However, in such a configuration, there is a possibility that the X-ray radiator and the X-ray camera cause optical axis shift due to the ups and downs of the track rail at the position where the X-ray radiator and the X-ray camera are added to the track rail and moved.

For this reason, complicated processes such as applying FB (feedback) on a linear scale to the distance traveled by the X-ray radiator and the X-ray camera for positioning are required, a high-precision transfer mechanism, and a high-strength mechanical housing body. Therefore, the X-ray position measuring device becomes very expensive.

Moreover, in order to improve the measurement accuracy of an X-ray camera, changing the positional relationship in the optical axis direction (up-down direction) of an X-ray radiator and an X-ray camera, enlarging an image, and improving resolution is performed. In this case, for example, when the optical axis of the X-ray radiator and the X-ray camera are aligned at an enlarged magnification of x1, any of the ranges in which the X-ray radiator or X-ray camera moves along the track rail with the enlarged magnification is increased. In the position, it is necessary to maintain the state where the radiation center of the X-ray emitter coincides with the optical axis of the X-ray camera. Therefore, also in this case, a highly accurate feed mechanism and a high strength mechanical housing body are required.

The present invention has been made in view of the above-described circumstances, and the position of the X-ray position measuring apparatus, the position measuring method of the X-ray position measuring apparatus, and the position of the X-ray position measuring apparatus which realize high position measuring accuracy without increasing the price. It aims to provide a program for measurement.

In order to achieve the above object, the X-ray position measuring device according to the first aspect of the present invention,

X-ray emitters and X-ray cameras;

A work table on which a measurement object (workpiece) is placed (ie, placed) (abbreviation of "workpiece");

A first moving unit for moving the X-ray radiator along a corresponding workpiece placing table surface with respect to a measurement object on the workpiece placing table;

A second moving unit for moving the X-ray camera along the workpiece placing table surface with respect to the measurement object on the workpiece placing table;

An image display unit radiating from the X-ray radiator and projecting X-rays passing through the measurement object as a first X-ray projection image;

A position correction jig disposed between the X-ray radiator and the X-ray camera and configured to project the X-ray radiated from the X-ray radiator as a second X-ray projection image which can be positioned on the image display unit;

A control unit for controlling the first moving unit and the second moving unit to independently move the X-ray radiator and the X-ray camera with respect to the work mounting table; And

A storage unit for storing a positional shift amount between at least the reference position in the image display unit and the position of the second X-ray projection image as a correction amount;

Wherein,

First moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position where position measurement is performed on the measurement object;

At the position where the position measurement is performed, the position shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is used as a correction amount corresponding to the measurement position. First measurement storage means stored in said storage unit;

Second moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing the position measurement;

At the position where the position measurement is performed, the first moving part and the second moving part are controlled on the basis of the correction amount so that the radiation center of the X-ray radiator and the optical axis of the X-ray camera are coincident with each other. It comprises a first position measuring means for performing a position measurement of the.

The X-ray position measuring device further includes a third moving unit for changing an enlarged magnification of the X-ray camera by moving one of the X-ray radiator and the X-ray camera in a direction perpendicular to the work placing table,

Wherein,

First magnification changing means for changing the magnification of the X-ray camera by controlling the third moving unit;

At the position of the X-ray camera at which a predetermined magnification is realized, the positional shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is applied. Second measurement storage means stored in the storage unit as a correction amount corresponding to an enlarged magnification;

Second magnification changing means for changing the magnification of the X-ray camera by controlling the third moving unit;

At the position of the X-ray camera at which a predetermined magnification is realized, the first moving part and the second moving part are controlled based on the correction amount to adjust the radiation center of the X-ray radiator and the optical axis of the X-ray camera. It is preferable to further include a second position measuring means for matching and at the same time performing position measurement of the measurement object.

It is preferable that it is a multilayer printed wiring board in which the positioning mark is provided in the position which the said measurement object performs position measurement.

Position measuring method of the X-ray position measuring apparatus according to the second aspect of the present invention,

X-ray emitters and X-ray cameras;

A work placing table for placing a measurement object;

A first moving unit for moving the X-ray radiator along a corresponding workpiece placing table surface with respect to a measurement object on the workpiece placing table;

A second moving unit for moving the X-ray camera along the workpiece placing table surface with respect to the measurement object on the workpiece placing table;

An image display unit radiating from the X-ray radiator and projecting X-rays passing through the measurement object as a first X-ray projection image;

A position correction jig disposed between the X-ray radiator and the X-ray camera and configured to project the X-ray radiated from the X-ray radiator as a second X-ray projection image which can be positioned on the image display unit;

A control unit for controlling the first moving unit and the second moving unit to independently move the X-ray radiator and the X-ray camera with respect to the work mounting table; And

A position measuring method used in an X-ray position measuring apparatus having a storage unit for storing a position shift amount between at least a reference position in the image display unit and a position in the second X-ray projection image as a correction amount,

A first moving step of controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position where position measurement is performed on the measurement object;

At the position where the position measurement is performed, the position shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is used as a correction amount corresponding to the measurement position. A first measurement memory step stored in the storage unit;

A second moving step of controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing the position measurement;

At the position where the position measurement is performed, the first moving part and the second moving part are controlled on the basis of the correction amount so that the radiation center of the X-ray radiator and the optical axis of the X-ray camera are coincident with each other. And a second position measurement step of performing position measurement.

The X-ray position measuring device further includes a third moving part for changing an enlarged magnification of the X-ray camera by moving one of the X-ray radiator and the X-ray camera in a direction perpendicular to the work placing table,

The position measurement method,

A first magnification changing step of changing the magnification of the X-ray camera by controlling the third moving unit;

At the position of the X-ray camera at which a predetermined magnification is realized, the positional shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is applied. A second measurement memory step stored in the storage unit as a correction amount corresponding to an enlarged magnification;

A second magnification changing step of changing the magnification of the X-ray camera by controlling the third moving unit;

At the position of the X-ray camera at which a predetermined magnification is realized, the first moving part and the second moving part are controlled based on the correction amount to adjust the radiation center of the X-ray radiator and the optical axis of the X-ray camera. It is preferable to further provide a 2nd position measuring step which performs the position measurement of the said measuring object simultaneously.

The position measuring program of the X-ray position measuring apparatus according to the third aspect of the present invention,

X-ray emitters and X-ray cameras,

A first moving unit for moving the X-ray radiator along the workpiece placing table surface with respect to the workpiece placing table on which the measurement object is placed and the measurement object on the workpiece placing table;

A second moving unit for moving the X-ray camera along the workpiece placing table surface with respect to the measurement object on the workpiece placing table;

An image display unit which is radiated from the X-ray radiator and projects X-rays transmitted through the measurement object as a first X-ray projection image;

A position correction jig disposed between the X-ray radiator and the X-ray camera and configured to project the X-ray radiated from the X-ray radiator as a second X-ray projection image which can be positioned on the image display unit;

A control unit for controlling the first moving unit and the second moving unit to independently move the X-ray radiator and the X-ray camera with respect to the work placement table;

A storage unit storing at least a position shift amount between a reference position in the image display unit and a position in the second X-ray projection image as a correction amount

A computer installed in the control unit of the X-ray position measuring device having a,

First moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing position measurement on the measurement object;

At the position where the position measurement is performed, the position shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is used as a correction amount corresponding to the measurement position. First measurement storage means stored in the storage;

Second moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing the position measurement; And

At the position where the position measurement is performed, the first moving part and the second moving part are controlled on the basis of the correction amount so that the radiation center of the X-ray radiator and the optical axis of the X-ray camera are coincident with each other. It is characterized by functioning as a second position measuring means for performing position measurement.

The X-ray position measuring device further includes a third moving part for changing an enlarged magnification of the X-ray camera by moving one of the X-ray radiator and the X-ray camera in a direction perpendicular to the work placing table,

The computer,

First magnification changing means for controlling the third moving part to change the magnification of the X-ray camera;

At the position of the X-ray camera at which a predetermined magnification is realized, the positional shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is applied. Second measurement storage means stored in the storage unit as a correction amount corresponding to an enlarged magnification;

Second magnification changing means for controlling the third moving part to change the magnification of the X-ray camera; And

At the position of the X-ray camera at which a predetermined magnification is realized, the first moving part and the second moving part are controlled based on the correction amount to adjust the radiation center of the X-ray radiator and the optical axis of the X-ray camera. At the same time, it is preferable to further function as the first position measuring means for performing the position measurement of the measurement object.

According to the present invention, high positioning accuracy can be realized without increasing the price.

1 is a perspective view showing the overall configuration of an X-ray position measuring device according to an embodiment of the present invention;
2 is a functional block diagram for explaining a hardware configuration of the X-ray position measuring device according to the embodiment of the present invention;
FIG. 3 (a) is a schematic side view of the X-ray position measuring device according to the embodiment of the present invention seen from the -Y direction of FIG. 1, and FIG. 3 (b) shows the position correction jig for use in the X-ray position measuring device. A plan view (ii) showing the assembled state of the plan view (i) and the position correction jig;
4 is a schematic plan view of an X-ray position measuring device according to an embodiment of the present invention;
5 is a schematic plan view showing coordinate positions of positioning marks on a multilayer printed wiring board;
6 is a schematic diagram showing a state where the center of radiation of the X-ray radiator, the optical axis of the X-ray camera, and the center positions of the micro holes of the position correction jig coincide with each other;
FIG. 7 is a schematic diagram showing a state in which the radiation center of the X-ray radiator and the optical axis of the X-ray camera cause a misalignment when the X-ray radiator and the X-ray camera move in the X direction; FIG.
8 is a schematic diagram showing a state in which the radiation center of the X-ray radiator coincides with the optical axis of the X-ray camera, and the optical axis of the X-ray camera does not coincide with the center position of the minute hole of the position correction jig;
9 is a schematic diagram showing a state where the center of radiation of the X-ray radiator, the optical axis of the X-ray camera, and the center positions of the micro holes of the position correction jig coincide with each other;
10 is a schematic diagram showing a state where the optical axis of the X-ray camera coincides with the center position of the minute hole of the position correction jig, and the optical axis of the X-ray camera does not coincide with the radiation center of the X-ray radiator;
11 is a schematic diagram showing a state in which the radiation center of the X-ray radiator and the optical axis of the X-ray camera cause a positional shift when the magnification of the X-ray camera is changed (Z-direction movement);
Fig. 12A is a schematic diagram showing a position measurement of a multilayer printed wiring board using an X-ray position measuring device, and Fig. 12B is a schematic plan view showing positioning marks displayed on an image display unit;
Fig. 13 is a flowchart showing the position measurement processing of the X-ray position measuring device when the X-ray radiator and the X-ray camera move in the X-direction.
Fig. 14 is a flowchart showing the position measurement processing of the X-ray position measuring device when the magnification of the X-ray camera is changed.

EMBODIMENT OF THE INVENTION Hereinafter, the X-ray position measuring apparatus which concerns on embodiment of this invention is demonstrated with reference to drawings.

The X-ray position measuring device according to the present embodiment measures the shape of a pair of positioning marks provided on the front and back surfaces of a multilayer printed circuit board (laminated substrate) that is a measurement target to determine the exact relative position of each printed board. The processing is performed.

As shown in Fig. 1, Fig. 2, Fig. 3A and Fig. 4, the X-ray position measuring apparatus 10 includes an X-ray radiator 10a and an X-ray camera 10b and a multilayer printed circuit board (in Fig. 1). The work placing table 10c of the rectangular frame shape which mounts not shown) is provided.

The X-ray position measuring apparatus 10 has a rectangular base stage 10d and a top surface (+ Z direction) from the center of the Y-direction of the base stage 10d in a plan view on a floor or a table. A standing plate 10e having a rectangular flat plate shape (that is, standing) is further provided. Each side of the base stand 10d follows the left-right direction (± X direction), the front-rear direction (± Y direction), and the up-down direction (± Z direction). The standing plate 10e extends in the left-right direction. The work placing table 10c is disposed in parallel with the surface of the base table 10d. The X-ray radiator 10a and the X-ray camera 10b are arrange | positioned so as to oppose to the up-down direction at the predetermined distance in the opening part of the workpiece | work mounting table 10c. X-rays radiated from the X-ray radiator 10a and transmitted through the multilayer printed substrate are captured as X-ray projection images on the light receiving surface of the X-ray camera 10b.

The X-ray camera 10b is supported by a Z-direction moving body 15 having an L-shaped cross section, and the Z-direction moving body 15 is interposed between a pair of first orbital rails 51. The first X-direction moving body 13 having a rectangular shape is supported to be movable in the vertical direction.

And the Z direction moving body 15 is guided to a pair of 1st orbit rail 51 by the Z motor (third moving part) 43 arrange | positioned at the 1st X direction moving body 13, It is movable with respect to the X direction moving body 13 in the direction (up-down direction) perpendicular | vertical to a workpiece | work mounting table surface (surface of a multilayer printed circuit board). This pair of 1st track rail 51 is arrange | positioned so that it may extend in a Z direction at the substantially center part of the side of + Y of the 1st X-direction moving object 13.

In this way, the X-ray camera 10b is moved in the direction perpendicular to the work placing table with respect to the X-ray radiator 10a, thereby transmitting the X-ray to the light-receiving surface of the X-ray camera 10b. It is possible to enlarge and reduce an image and change its magnification.

That is, when the distance between the X-ray radiator 10a and the X-ray camera 10b is enlarged, the image in the image display part 45 will enlarge and the resolution will improve. For example, as shown in Fig. 12 (a), from the + Z side end face of the X-ray radiator 10a to the + Z side end face of the multilayer printed circuit board 70 (copper foil 74) to be measured. Is referred to as " Ld1 " from the + Z side end face of the multilayer printed circuit board 70 (copper foil 74) to the -Z side end face of the light receiving surface 100 of the X-ray camera 10b. The distance is called "Ld2". And when (Ld2) is enlarged while keeping (Ld1) constant, the image of the positioning mark (70m) of the multilayer printed substrate 70 projected on the light receiving surface 100 of the X-ray camera 10b. From the state projected only on a part of the light receiving surface 100, the lens is enlarged to be projected onto the entire surface of the light receiving surface 100. As the size of the image of the positioning mark 70m of the multilayer printed circuit board 70 projected onto the light receiving surface 100 is enlarged in this way, the resolution of the image is improved.

In addition, the multilayer printed circuit board 70 shown to Fig.12 (a) is the copper foil 74, the prepreg (surface side printed circuit board) 71, the copper foil 75, and the prepreg 72 from the upper side. ), A copper foil 76, a prepreg (back side printed board) 73, and a copper foil 77 are laminated. In the copper foil 75 and the copper foil 76, a large diameter circle mark 70a and a small diameter circle mark 70b are disposed (printed) as marks for positioning, respectively.

The first X-direction moving body 13 is movable in the X direction with respect to the entrance plate 10e via a pair of 2nd orbital rail 52. As shown in FIG. This pair of 2nd orbital rail 52 is arrange | positioned so that it may extend in a X direction at the upper-lower periphery edge part of the side of the + Y side of the entrance plate 10e.

And the 1st X direction moving body 13 is guided to the 2nd orbit rail 52 by the 1st X motor (1st moving part) 11 arrange | positioned at the entrance plate 10e, and the entrance plate 10e. It is movable in the X direction along ().

Moreover, the X-ray camera 10b is X direction and Y with respect to the Z direction moving body 15 with the 3rd X motor 31 and the 3rd Y motor 32 arrange | positioned on the Z direction moving body 15. It is movable in a small range in the direction.

The X-ray radiator 10a is mounted on the rectangular X-shaped moving body 14 in the form of a rectangular flat plate, and the second X-direction moving body 14 carries a pair of third orbital rails 53 extending in the X direction. It is movable in the X direction with respect to the base stand 10d via.

And the 2nd X direction moving body 14 (X-ray radiator 10a) is the 3rd orbital rail 53 by the 2X motor (2nd moving part) 21 arrange | positioned at the base stand 10d. It is guided to and is movable in the X direction with respect to the base stand 10d. A pair of 3rd orbital rail 53 and the 2nd X motor 21 are arrange | positioned in the bottom surface of the groove part 10f formed so that it may extend in a X direction in the center part of the base stand 10d (refer FIG. 1).

In addition, the X-ray radiator 10a moves in the Y direction with respect to the second X-direction moving body 14 by a second Y motor 22 disposed on the second X-direction moving body 14. It is possible.

As described above, the X-ray radiator 10a and the X-ray camera 10b are independent of the multilayer printed circuit board on the work mounting table 10c by the first X motor 11 and the second X motor 21, respectively. This makes it possible to move along the workpiece placement table surface.

The workpiece placing table 10c is movable in the Y direction with respect to the base base 10d via a pair of third orbital rails 54. The third orbital rail 54 is disposed to extend in the Y direction at the left and right peripheral edge portions of the base table 10d (see FIG. 4).

Then, the work placing table 10c is moved in the Y direction with respect to the base stand 10d while being guided to the third orbit rail 54 by the fourth Y motor 42 disposed on the base stand 10d. It is possible. In this manner, the work placing table 10c is movable in the Y direction independently of the X-ray radiator 10a and the X-ray camera 10b. For this reason, the X-ray radiator 10a and the X-ray camera 10b are movable to the Y direction with respect to the multilayer printed circuit board 70 which is a measurement object, in the state fixed to the predetermined position with respect to the base stand 10d. It is supposed to be done.

As shown in FIG. 1, in the X-ray position measuring apparatus 10, the X-ray camera 10b is arrange | positioned above the workpiece | work mounting table 10c (multilayer printed board 70). This is because there is not enough space below the workpiece placing table 10c for separating the X-ray camera 10b from the multilayer printed circuit board 70 which is a measurement object. As shown in Fig. 1 and Fig. 3 (a), by placing the X-ray camera 10b above the work placing table 10c (multilayer printed circuit board 70), the X-ray camera 10b is placed on the X-ray radiator. It becomes possible to arrange | position further from 10a, and the further increase of the magnification of an X-ray projection image is realized.

In the present embodiment, the first X-ray projection image 101 or the second X-ray projection image by moving the X-ray camera 10b in a direction perpendicular to the work placing table 10c with respect to the X-ray radiator 10a. (102) is enlarged and reduced, and the enlargement ratio is changed. When high measurement accuracy is required, the image is enlarged to increase the resolution. On the contrary, it is easy to specify the predetermined measurement position in the measurement object by lowering the magnification and projecting a wide range.

When the first X-ray projection image 101 or the second X-ray projection image 102 is enlarged, a method of reducing the distance Ld1 in a state where the distance Ld2 shown in FIG. Is considered. However, if the distance Ld1 is made too small, there is a possibility that the quality of the product may deteriorate, such as contact with the multilayer printed circuit board 70, resulting in damage. Further, even when the distance Ld1 is made small, there is a limit because the structure around the light receiving surface 100 of the X-ray camera 10b becomes an obstacle.

As another method of enlarging the first X-ray projection image 101 or the second X-ray projection image 102, a method of increasing the distance Ld2 in a state where the distance Ld1 is made constant is also considered. In this case, there are fewer restrictions than making the distance Ld1 small. For this reason, as long as the size expansion of the X-ray position measuring device 10 is permitted, the first X-ray projection image 101 or the second X-ray projection image 102 can be easily enlarged. Therefore, in this embodiment, the method of enlarging an image is employ | adopted by making the distance Ld2 of the X-ray camera 10b and the multilayer printed circuit board 70 large.

As shown in FIG. 2, the X-ray position measuring apparatus 10 includes a controller (control unit) 81, an image display unit 45, an X-ray radiator driver 46, and a storage unit 47 having a central processing unit (CPU). ) And an input unit 48 are provided. These image display section 45, X-ray radiator drive section 46, storage section 47 and input section 48 are connected to the controller 81, respectively.

In addition, the controller 81 includes a servomotor group 44 for driving each component of the above-described X-ray position measuring apparatus 10, that is, the first X motor 11 and the second X motor 21 described above. ), The Z motor 43, the second Y motor 22, the third X motor 31, the third Y motor 32, and the fourth Y motor 42 (see FIG. 1) are connected.

The image display section 45 is connected to the X-ray camera 10b. And the X-ray projection image projected on the light receiving surface of the X-ray camera 10b is the 1st X-ray projection image by X-ray which permeate | transmitted the multilayer printed circuit board on the display screen of the image display part 45, or a position grasp. It is projected as a possible 2nd X-ray projection image. This 2nd X-ray projection image is obtained by the position correction jig 61 (refer FIG. 3 (b)) mentioned later, in the state in which the multilayer printed circuit board is not mounted on the workpiece | work table 10c.

In the controller 81, the first X-ray projection image and the second X-ray projection image displayed on the display screen of the image display unit 45 are subjected to image processing. In this image process, the controller 81 performs position measurement of the multilayer printed circuit board 70 which is a measurement object based on a 1st X-ray projection image. Moreover, the measurement of the position shift amount between the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b is performed based on the 2nd X-ray projection image.

As described above, the X-ray position measuring device 10 adjusts the separation distance between the X-ray radiator 10a and the X-ray camera 10b to project the X-ray projection image projected onto the light receiving surface of the X-ray camera 10b. Can be enlarged and displayed on the display screen of the image display section 45. When the position measurement is performed while the X-ray projection image is enlarged, the resolution per pixel of the image is increased, so that the position measurement can be performed with higher accuracy. For this reason, it is preferable to perform positioning in the state which raised the magnification of an X-ray projection image as much as possible. However, it is preferable to select an appropriate magnification factor in consideration of the complexity of the position measurement operation and the required position measurement accuracy.

The X-ray radiator drive unit 46 is connected to the X-ray radiator 10a to radiate or stop X-rays from the X-ray radiator 10a based on input information from the input unit 48. .

The storage unit 47 includes a nonvolatile memory such as random access memory (RAM), read only memory (ROM), and semiconductor memory. The storage unit 47 drives the program executed by the controller 81, various parameters necessary for the execution of the program, and the servomotor group 44 to move the X-ray radiator 10a and the X-ray camera 10b. Various kinds of information for storing the information are stored.

The input unit 48 is configured to include a power switch, an operation panel for inputting a command to the X-ray position measuring device 10, and the like, and receives an input from a user. The instruction from the user is input via this input part 48, and the controller 81 is notified.

As shown to Fig.3 (a), the X-ray position measuring apparatus 10 of this embodiment is interposed between the X-ray radiator 10a and the X-ray camera 10b, and radiates from the X-ray radiator 10a. A position correction jig 61 for projecting the X-rays to be projected as a second X-ray projection image that can be grasped by the image display unit 45 is provided.

The position correction jig 61 is composed of a rectangular flat plate-shaped fixing plate 62 and a disc jig 63 having a micro hole 65 in the center thereof, as shown in Fig. 3B. The disc jig 63 is detachably held by the holding opening 64 formed in the fixing plate 62.

As shown to Fig.3 (a), the fixing plate 62 is the 1st in the state where the relative position with the X-ray camera 10b in a Z-axis direction is determined from the lower side of the X-ray camera 10b. It is fixed with a bolt and a nut in the predetermined position of the X direction moving body 13. In this way, the position correction jig 61 moves together with the first X-direction moving object 13.

The disk jig 63 is formed of metal, such as lead, so that the X-ray from the X-ray radiator 10a may be shielded. In the state where the disc jig 63 is inserted into the holding opening 64 of the fixing plate 62, the optical axis L of the X-ray camera 10b is the center of the minute hole 65 of the disc jig 63. It is designed to pass through the location.

When the disc jig 63 is held on the fixing plate 62, the X-rays passing through the minute hole 65 of the disc jig 63 among the X-rays radiated from the X-ray radiator 10a are transferred to the image display unit ( It is projected as a 2nd X-ray projection image 102 (refer FIG. 6) on the display screen of 45 (refer FIG. 3 (a)). Although details will be described later, the image display unit 45 in a state where the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b are positioned at the machine origin of the X-ray position measuring apparatus 10. For the position correction so that the center point O 'of the second X-ray projection image projected onto the X1) coincides with the reference position (center position) O (see FIGS. 6 and 8) formed on the display screen of the image display section 45 The relative position of the jig 61 and the X-ray radiator 10a and the X-ray camera 10b is adjusted.

On the other hand, when the disc jig 63 is not held on the fixing plate 62, the X-rays radiated from the X-ray radiator 10a pass through the opening opening 64 of the fixing plate 62, It is projected as a 1st X-ray projection image 101 (refer FIG. 12 (b)) on the display screen of the image display part 45. FIG.

When performing the positioning measurement of the positioning mark 70m provided on the multilayered printed circuit board 70 by the X-ray radiator 10a and the X-ray camera 10b, the specific positioning will be described with reference to FIGS. 4 and 5. The X-ray radiator 10a and the X-ray camera 10b are moved on the coordinate position of the mark 70m. Here, a plurality of positioning marks 70m are provided along each side of the multilayer printed circuit board 70. Specifically, the positioning mark 70m is (2, 1) to (n-1, 1) in the XY coordinates shown in FIG. 5 formed on the multilayer printed circuit board 70; (m, 2)-(n-1, m); (2, 1)-(m-1, 1); It is provided in each coordinate position of (n, 2)-(n, m-1). Moreover, in the multilayer printed circuit board 70, the origin position is provided in the coordinate position of (1, 1).

When performing positioning measurement of the positioning mark 70m provided in the multilayered printed circuit board 70, the X-ray radiator 10a and the X-ray camera 10b are the 2nd X-direction moving body 14 and the 1st X, respectively. It moves along the 3rd orbital rail 53 and the 2nd orbital rail 52 via the directional movable body 13 (refer FIG. 1). As shown in FIG. 7, the radiation center and the X-ray camera of the X-ray radiator 10a are caused by the undulation of the third orbital rail 53 and the second orbital rail 52 at the coordinate position of the moving destination. The position shift of the optical axis L of 10b is caused. In addition, even if the X-ray position measuring device 10 moves the X-ray radiator 10a and the X-ray camera 10b by the same distance in the X direction due to the feeding accuracy, the working accuracy, the assembly error, etc. There is. As a result, as shown in Fig. 7, the second X-ray projection image 102 is in a position shifted from the center position O of the display screen of the image display section 45, so that accurate position measurement cannot be performed. do.

Hereinafter, the positional relationship between the radiation center of the X-ray radiator 10a, the optical axis L of the X-ray camera 10b, and the second X-ray projected image 102 and the position measurement accuracy will be described. In the state shown in FIG. 8, the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b correspond. However, the center position of the microhole 65 of the position correction jig 61 produces a position shift in the + X direction and does not coincide. Therefore, the microhole 65 is displayed on the image display part 45 in the + X direction from the center position O of the image display part 45 as the 2nd X-ray projection image 102. As shown in Fig. 8, X-rays are emitted so that the projection area is enlarged in sequence. Therefore, even if the measurement object has the same distance from the X-ray radiator 10a, the measurement object is used as the second X-ray projection image 102 on the image display unit 45 according to the separation distance at the radiation center of the X-ray radiator 10a. The magnification will be different when projected.

Specifically, as shown in FIG. 8, from the end point on the -X side of the microhole 65 of the position correction jig 61 projected as the second X-ray projection image 102 on the image display unit 45. The distance from the center point O 'of the second X-ray projection image 102 to the center point O' of the second X-ray projection image 102 corresponding to the center position of the minute hole 65 is "La". If the distance to the end point on the + X side of the microhole 65 is "Lb", La <Lb. That is, as the result of the projection of the micro-holes 65 having a round shape as the second X-ray projection image 102 on the image display portion 45, the microscopic holes 65 are projected in a slightly distorted shape. When the center point of the second X-ray projected image 102 projected in the distorted shape as described above is measured, the center point (ie, the second point) that causes a position shift from the true center point O 'of the second X-ray projected image 102 is measured. The apparent center point (O ") on the X-ray projection is mistaken for the true center point (O ') and detected.

On the other hand, as shown in FIG. 9, the radiation center of the X-ray radiator 10a, the optical axis L of the X-ray camera 10b, and the center position of the microhole 65 of the position correction jig 61 match, If so, the micro holes 65 are projected onto the image display section 45 without being distorted in shape, and La = Lb. For this reason, the center position of the microhole 65 can be measured correctly from the 2nd X-ray projection image 102.

That is, in performing high-precision position measurement, not only the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b correspond, but also the center position of the microhole 65 It is desirable to coincide. However, the radiation center of the X-ray radiator 10a, the optical axis L of the X-ray camera 10b, and the position of the center of the microhole 65 of the position correction jig 61 do not have to be exactly identical. It is only necessary that they match within the range according to the positioning accuracy to be achieved.

As in the present embodiment, even when the positioning measurement of the positioning mark 70m provided on the multilayer printed circuit board 70 is performed, as described above, the radiation center of the X-ray radiator 10a and the X-ray camera 10b Position measurement is preferably performed in the state where the center point of the optical axis L and the positioning mark 70m coincide with each other.

Specifically, position measurement is performed as follows. For example, in the XY coordinates shown in FIG. 5, the X-ray radiator 10a and the X-ray camera 10b are mounted in order to perform position measurement of the positioning mark 70m at the position of (2, 1). When it moves, the position shift which occurred at the time of printing the positioning mark 70m on the multilayer printed circuit board 70, and the multilayer printed circuit board 70 itself make expansion and contraction by the temperature and humidity of an atmosphere. For this reason, the center point of the optical axis L of the X-ray camera 10b and the positioning mark 70m in the coordinate position of (2, 1) do not necessarily correspond.

If position measurement is performed in such a state, position measurement cannot be performed accurately as described above. For this reason, the position shift amount between the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b is measured once. Then, the X-ray camera 10b and the X-ray radiator 10a are moved by the distance according to the position shift amount so that the position shift amount may be offset. Then, the radiation center of the X-ray radiator 10a and the center point of the optical axis L of the X-ray camera 10b and the positioning mark 70m are made to match within the range required for the positioning accuracy.

By doing so, it becomes possible to perform positioning measurement of the positioning mark 70m with high accuracy. In other words, the position measurement can be performed in a state where the amount of distortion when the micro holes 65 are projected onto the image display unit 45 as the second X-ray projection image 102 is sufficiently small. Thus, in this embodiment, after performing positioning of the X-ray camera 10b and the positioning mark 70m once, operation for canceling the position shift amount only once is performed. In addition to this, if the positioning is to be performed with high accuracy, the operation for canceling the positional shift may be repeated until the required precision is obtained.

In the present embodiment, the controller 81 of the X-ray position measuring device 10 is used when positioning the relative position of the X-ray camera 10b and the X-ray radiator 10a with respect to the positioning mark 70m. The movement pulses of the first X motor 11, the second X motor 21, and the fourth Y motor 42 are stored. And the controller 81 can grasp | ascertain the relative position of the positioning mark 70m with respect to the machine origin of the X-ray positioning apparatus 10 based on the memory value of this movement pulse.

As described above, in the present embodiment, the X-ray radiator 10a and the X-ray camera 10b are independently moved in the X direction at the time of the position measurement of the measurement object. For this reason, the phenomenon that the stop position of the X-ray radiator 10a and the X-ray camera 10b displace | deviate from each other at the movement destination potentially arises. If such a position shift occurs, and the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b do not coincide, the following results are obtained.

That is, in FIG. 10, although the optical axis L of the X-ray camera 10b and the center position of the microhole 65 match, the optical axis L and X-ray radiator 10a of the X-ray camera 10b do not correspond. Radiation centers represent states of mismatch. As shown in Fig. 10, the X-rays are emitted so that the projection area is enlarged in sequence. Therefore, although the center position of the microhole 65 and the optical axis L of the X-ray camera 10b match, in the state projected as the 2nd X-ray projection image 102 on the projection part 45, The 2nd X-ray projection image 102 is projected in the state which caused the position shift in the + X direction. In addition, similarly to the case shown in FIG. 8, the second X-ray projection image 102 from the end point on the -X side of the microhole 65 projected on the image display unit 45 as the second X-ray projection image 102. Is the distance from the center point O 'of the second X-ray projection image 102 to the end point on the + X side of the microhole 65, " Lb " La <Lb. That is, as a result of the projection of the micro-hole 65 of a round shape as the 2nd X-ray projection image 102 to the image display part 45, it becomes a slightly distorted shape.

When the center point of the second X-ray projected image 102 projected in the distorted shape is measured, the center point O ″ causing the position shift from the true center point O 'of the second X-ray projected image 102 is determined. In this state, in order to correct the distortion of the second X-ray projected image 102, the center point O ″ of the second X-ray projected image 102 is detected. When the position correction jig 61 (micro hole 65) is moved so that the optical axis L of the X-ray camera 10b coincides, the optical axis L and the micro hole 65 of the X-ray camera 10b are moved. From the state where the center positions of the two coincide with each other, position shift occurs, and the accuracy of the position measurement deteriorates.

Therefore, in the X-ray position measuring device 10 of the present embodiment, the radiation center of the X-ray radiator 10a and the X-ray radiator 10a at the time of moving in the X-direction of the X-ray radiator 10a and the X-ray camera 10b in advance. The amount of position shift on the XY plane with the optical axis L of the X-ray camera 10b is measured and stored as a correction amount. And when performing the position measurement of a multilayer printed circuit board actually, using the correction amount, the position (position of the positioning mark 70m) in the multilayer printed circuit board 70, the X-ray radiator 10a The relative position of the center of radiation and the optical axis L of the X-ray camera 10b is corrected.

Hereinafter, the example is demonstrated referring a flowchart of FIG. The position measurement processing here is executed by the controller 81 by a program stored in the storage unit 47.

<Acquisition of correction amount at the time of X direction movement of X-ray radiator 10a and X-ray camera 10b>

Before actually performing the position measurement of the multilayered printed circuit board using the X-ray position measuring device 10, the amount of correction when the X-ray radiator 10a and the X-ray camera 10b move in the X direction is obtained. Here, the multilayer printed circuit board is not placed on the work mounting table 10c. In addition, the magnification of the X-ray camera 10b is made constant at a predetermined magnification (here, x1). It is preferable to acquire this correction amount every time the position measurement of one multilayer printed circuit board is performed. However, the present invention is not limited to this, and may be performed every time the position measurement of a plurality of multilayer printed circuit boards is performed. It is also possible to determine the timing regardless of the number of multilayer printed circuit boards for performing position measurement.

First, at the origin positions 1 and 1 of the multilayer printed circuit board 70 shown in FIG. 5, the alignment between the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b is performed. . Here, it is assumed that the origin positions 1 and 1 of the multilayer printed circuit board 70 and the machine origin of the X-ray position measuring apparatus 10 are at the same coordinate position. At this time, the disk jig 63 is removed from the position correction jig 61 attached to the first X-direction moving body 13.

Next, using the optical axis alignment jig (not shown) of the same structure as the position correction jig 61 shown in FIG.3 (b), the fixing plate is fixed to the predetermined position of the workpiece | work mounting table 10c. Here, "predetermined position" means that the power supply is turned on to the X-ray position measuring device 10, and the above-mentioned first X motor 11, second X motor 21, second Y motor 22, and third For fixing in the state where the positioning (reset operation) to the machine origin of the X-ray position measuring device 10 by the X motor 31, the third Y motor 32, and the fourth Y motor 42 is completed. When the plate is fixed at the predetermined position of the work placing table 10c (see FIG. 3 (a)), the center position (center coordinate of the hole) of the micro hole 65 of the disc jig 63 attached to the fixing plate. And the origin positions 1 and 1 shown in FIG. 5 coincide.

6, the 2nd X-ray projection image by the microhole 65 of the optical-axis alignment jig fixed to the predetermined position of the workpiece | work table 10c projected on the display screen of the image display part 45 ( The first X motor 11, the second X motor 21, the second Y motor 22, and the first 102 so that 102 is positioned at a reference position (center position) O of the display screen of the image display unit 45. 3 The relative position of the X-ray radiator 10a and the X-ray camera 10b is changed using the X motor 31 and the 3rd Y motor 32 (refer FIG. 1). And by this operation, the radiation center of the X-ray radiator 10a, the optical axis L of the X-ray camera 10b, and the home position (machine origin) of the multilayer printed circuit board 70 are made to correspond.

Next, the fixing plate fixed at the predetermined position of the work placing table 10c is removed. Moreover, the disk jig 63 is attached to the position correction jig 61 attached to the 1st X-direction moving body 13 (refer FIG. 3 (a) and FIG. 3 (b)).

Then, the controller 81 at the origin position (machine origin) shown in Fig. 5 in which the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide, the second X at that time. Using the line projection image 102, the XY coordinate of the center position (center point O 'of the 2nd X-ray projection image 102) of the microhole 65 of the position correction jig 61 is measured. Then, the controller 81 stores the XY coordinates in the storage unit 47 (step S1). By this operation, the origin position (machine origin) of the multilayer printed circuit board 70 shown in FIG. 5 and the center position of the microhole 65 of the disc jig 63 attached to the first X-direction moving body 13 are Related. Further, the alignment is performed in advance so that the center position of the microhole 65 of the position correction jig 61 attached to the first X-direction moving body 13 and the optical axis L of the X-ray camera 10b coincide with each other.

This positioning is performed as follows, for example. That is, first, by the operation of the servomotor group 44, the center point O 'of the second X-ray projected image 102 and the center position O of the display screen of the image display section 45 coincide. Then, the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b and the minute hole 65 of the optical axis alignment jig 61 fixed at a predetermined position of the work placing table 10c. Match the center position. Thereafter, the opening 64 for holding the fixing plate fixed to the predetermined position of the work placing table 10c, and the opening 64 for holding the position correction jig 61 attached to the first X-direction moving body 13. A pin-shaped jig having the same diameter as the two openings 64 and 64 is inserted and passed vertically. Thereby, alignment of the two openings 64 and 64 on the XY coordinates is performed, and the position of the optical axis alignment jig fixed to the predetermined position of the work placing table 10c and the first X-direction moving object 13 are fixed. The position of the attached position correction jig 61 coincides.

Moreover, by the method mentioned above, the center position of the microhole 65 of the position correction jig 61 attached to the 1st X-direction moving body 13, and the optical axis L of the X-ray camera 10b will correspond. Even if the alignment is performed in advance, there is a possibility that a positional shift due to the part precision, for example, a positional shift of the degree of fitting tolerance, may occur. However, even in such a case, if the positional displacement amount is enough to satisfy the required accuracy, the positional displacement amount at that time is stored in the storage unit 47, and the positional displacement amount is added to the correction value to perform the position measurement operation. do. In addition, in this embodiment, the center position of the microhole 65 of the position correction jig 61 attached to the 1st X-direction moving body 13, the radiation center of the X-ray radiator 10a, and the X-ray camera 10b ) Optical axis L coincides and assumes no position shift.

Next, the controller 81 controls the first X motor 11, the second X motor 12, and the fourth Y motor 42 to multilayer the X-ray radiator 10a and the X-ray camera 10b. It sequentially moves to each coordinate position of the positioning mark 70m of the printed board 70 (step S2).

Specifically, in the XY coordinates shown in FIG. 5, the X-ray radiator 10a and the X-ray camera 10b are (2, 1) to (n-1, 1); (m, 2)-(n-1, m); (2, 1)-(m-1, 1); It moves to the positioning mark 70m provided in each coordinate position of (n, 2)-(n, m-1) sequentially. Specifically, in the X direction, the X-ray radiator 10a and the X-ray camera 10b are moved using the first X motor 11 and the second X motor 12. In the Y direction, the work placing table 10c on which the multilayer printed circuit board 70 is placed is moved using the fourth X motor 42.

Next, with reference to FIG. 7, the controller 81 displays the image data of the image display part 45 on which the 2nd X-ray projection image 102 was projected in each coordinate position of all the positioning marks 70m. Using this, the position shift amount (DELTA) X1, (DELTA) Y1 of the XY coordinate of the center point O 'of the 2nd X-ray projection image 102, and the optical axis L of the X-ray camera 10b is measured. The position shift amounts ΔX1 and ΔY1 are also stored in the storage unit 47 as correction amounts (step S3).

Specifically, with reference to FIG. 7, the center position (second position) of the microhole 65 of the position correction jig 61 in the origin position (machine origin) shown in FIG. 5 stored in the memory | storage part 47 is shown. The XY coordinate of the center point O 'of the X-ray projection image 102 is set to the center position O of the display screen of the image display section 45. The second X-ray on the display screen of the image display section 45 at the coordinate position where the center position O and the X-ray radiator 10a and the X-ray camera 10b have moved in the X-direction. The XY coordinates of the center point O '(the center position of the micropores 65) of the projected image 102 are compared, and the positional shift amounts ΔX1 and ΔY1 as the correction amounts are measured. The controller 81 corresponds to the magnification of the X-ray camera 10b (the position in the Z direction of the X-ray camera 10b) and the coordinate positions of the positioning marks 70m, respectively. The correction amount is sequentially stored in the storage unit 47. After storing the correction amount at each coordinate position of all the positioning marks 70m, the disk jig 63 is removed from the position correction jig 61.

Subsequently, in order to actually measure the position of the multilayer printed board using the X-ray position measuring device 10, the multilayer printed board is placed and fixed on the work placing table 10c (see Fig. 3 (a)). . Here, 70 m of positioning marks of a multilayer printed circuit board are (2, 1)-(n-1, 1) in XY coordinates shown in FIG. (m, 2)-(n-1, m); (2, 1)-(m-1, 1); The multilayer printed circuit board is mounted and fixed on the work placing table 10c in a state where positioning is performed so as to correspond to each coordinate position of (n, 2) to (n, m-1).

<Position Measurement of Multilayer Printed Boards>

Next, the controller 81 performs the first X motor 11, the second X motor 21, and the fourth Y motor 42 to perform position measurement at each positioning mark 70 m of the multilayer printed circuit board. ), The X-ray radiator 10a and the X-ray camera 10b are moved to the coordinate positions of the positioning mark 70m described above (step S4).

And the controller 81 is the magnification of the X-ray camera 10b (the Z-direction position of the X-ray camera 10b) in the coordinate position which the X-ray radiator 10a and the X-ray camera 10b moved. Here, for each coordinate position of the positioning mark 70m, using the correction amounts ΔX1 and ΔY1 stored in the storage unit 47 in correspondence with the corresponding coordinate positions of the positioning mark 70m, The second X motor 21 and the second Y motor 22 (see Figs. 1 and 3A) are controlled. Then, the controller 81 moves the X-ray radiator 10a by the second X motor 21 and the second Y motor 22 in the XY direction by ΔX1 and ΔY1 equivalent amounts so that the correction amount is canceled, and X The radiation center of the ray emitter 10a and the optical axis L of the X-ray camera 10b coincide (step S5). In this case, since the center positions of the optical axis L and the microhole 65 of the X-ray camera 10b are already coincident with the above adjustments, the second X motor 21 and the second Y motor 22. The X-ray radiator 10a may be moved so that the radiation center of the X-ray radiator 10a coincides with the center position of the microhole 65.

By doing so, even if the X-ray radiator 10a and the X-ray camera 10b are independently moved by approximately the same distance in the X direction based on the respective position coordinates of the positioning mark 70m, Figs. 6 and 12 As shown in (a), the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide at each coordinate position of the positioning mark 70m of the multilayer printed circuit board. The position measurement is performed accurately at.

Specifically, as shown in FIG. 12B, the original mark 70b applied to the multilayer printed circuit board 70 and the original mark 70a applied to the copper foil 2 are provided on the image display unit 45. The position measurement of the projected first X-ray projection image 101 is performed in a state where the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide. As a result, the position measurement of the multilayer printed circuit board 70 is performed correctly.

As a result of the above-described position measurement operation, the controller 81 ends the process when the position measurement is completed for all the positioning marks 70m of the multilayer printed circuit board 70.

As described above, in the X-ray position measuring apparatus 10, the magnification can be adjusted by moving the X-ray camera 10b in the vertical direction with respect to the X-ray radiator 10a. As shown in FIG. 6, the X-ray camera 10b is moved along the first orbit rail 51 from the state where the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide. When moved upward, the optical axis center of the X-ray camera 10b moves along this initial optical axis L by design. However, as shown in Fig. 11, in practice, the optical axis center of the X-ray camera 10b is caused by various factors such as the ups and downs of the first orbit rail 51 (see Fig. 3 (a)). L) out of it. As a result, as shown in Fig. 11, the center point O 'of the second X-ray projection image 102 is in a state where a position shift occurs from the center position O of the display screen of the image display section 45, and the Position measurement cannot be performed.

Therefore, in the X-ray position measuring device 10 of the present embodiment, the radiation center of the X-ray radiator 10a and the X-ray camera 10b at the time of changing the magnification of the X-ray camera 10b in advance. The amount of positional deviation from the optical axis L is measured and stored as a correction amount. When the magnification of the X-ray camera 10b is actually changed, the correction amount is used to correct the position of the radiation center of the X-ray radiator 10a and the position of the optical axis L of the X-ray camera 10b.

Hereinafter, the example is demonstrated referring a flowchart of FIG. The position measurement processing here is executed by the controller 81 by a program stored in the storage unit 47.

<Acquisition of correction amount at the time of magnification change (Z direction movement) of X-ray camera 10b>

Before actually changing the magnification of the X-ray camera 10b using the X-ray position measuring device 10, a correction amount at the time of changing the magnification of the X-ray camera 10b is obtained. Here, the multilayer printed circuit board is not placed on the work mounting table 10c. In addition, the initial magnification of the X-ray camera 10b is set to a predetermined magnification (here, x1). It is preferable to acquire this correction amount every time the position measurement of one multilayer printed circuit board is performed. However, the present invention is not limited to this, and may be performed every time the position measurement of a plurality of multilayer printed circuit boards is performed. It is also possible to determine the timing regardless of the number of multilayer printed circuit boards for performing position measurement.

Here, it is assumed that the alignment of the optical center L of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b and the machine origin are already completed.

Next, using the fixing plate 62, the position correction jig 61 is fixed to a predetermined position of the first X-direction moving object 13 on the lower side of the X-ray camera 10b (Fig. 3 (a)). And FIG. 3 (b)).

Then, the controller 81 at the origin position (machine origin) shown in Fig. 5 in which the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide, the second X at that time. Using the line projection image 102, the XY coordinate of the center position (center point O 'of the 2nd X-ray projection image 102) of the microhole 65 of the position correction jig 61 is measured. And the controller 81 memorize | stores the XY coordinate in the memory | storage part 47 (step S11). As described above, the center position of the minute hole 65 of the position correction jig 61 attached to the first X-direction moving object 13 and the optical axis L of the X-ray camera 10b are attributable to component precision. Position shift, for example, position shift of the fitting tolerance degree may occur. However, even in such a case, as long as the position shift amount is enough to satisfy the required accuracy, the position shift amount may be stored in the storage unit 47, and the position shift amount may be added to the correction amount to perform the position measurement operation. . In addition, in this embodiment, the center position of the microhole 65 of the position correction jig 61 attached to the 1st X direction moving body 13, the radiation center of the X-ray radiator 10a, and the X-ray camera 10b Let the optical axis L of coincide and there will be no position shift.

Next, the controller 81 controls the Z motor 43 to move the X-ray camera 10b along the Z-direction to increase the magnification of the X-ray camera 10b by a predetermined magnification (for example, × 2, x 4, x 6) (step S12).

Next, the controller 81 refers to the image display part 45 on which the 2nd X-ray projection image 102 was projected in the Z direction position of the X-ray camera 10b corresponding to each enlargement magnification. Using the image data of the X-ray projection image 102, the positional shift amounts ΔX2 and ΔY2 of the XY coordinates of the center point O 'of the second X-ray projection image 102 and the optical axis L of the X-ray camera 10b are measured. . The controller 81 stores the position shift amounts ΔX2 and ΔY2 in the storage unit 47 as correction amounts (step S13).

Specifically, with reference to FIG. 11, the center position (second position) of the microhole 65 of the position correction jig 61 in the origin position (machine origin) shown in FIG. 5 stored in the memory | storage part 47 is shown. The XY coordinate of the center point O 'of the X-ray projection image 102 is set to the center position O of the display screen of the image display section 45. And this center position O and the center point of the 2nd X-ray projection image 102 in the display screen of the image display part 45 in the previous coordinate position which the X-ray camera 10b moved to Z direction. The XY coordinates of (O ') (the center position of the micropores 65) are compared, and the position shift amounts ΔX2 and ΔY2 as the correction amounts are measured. The controller 81 sequentially stores the correction amount at the Z-direction position in the storage unit 47 in correspondence with the magnification of the X-ray camera 10b (the Z-direction position of the X-ray camera 10b). do. After the correction amounts at all magnifications are stored, the disc jig 63 is removed from the position correction jig 61.

Subsequently, in order to actually measure the position of the multilayer printed board using the X-ray position measuring device 10, the multilayer printed board is placed and fixed on the work placing table 10c (see Fig. 3 (a)). . Here, 70 m of positioning marks of a multilayer printed circuit board are (2, 1)-(n-1, 1) in XY coordinates shown in FIG. (m, 2)-(n-1, m); (2, 1)-(m-1, 1); The multilayer printed circuit board is mounted and fixed on the work placing table 10c in a state where positioning is performed so as to correspond to each coordinate position of (n, 2) to (n, m-1).

<Position Measurement of Multilayer Printed Boards>

Next, the controller 81 performs the first X motor 11, the second X motor 21, and the fourth Y motor in order to perform position measurement at a predetermined positioning mark 70 m of the multilayer printed circuit board. 42, the X-ray radiator 10a and the X-ray camera 10b are moved to the coordinate positions of any of the positioning marks 70m described above (step S14).

The controller 81 stores the correction amount stored in the storage unit 47 in correspondence with the magnification of the X-ray camera 10b (here, initial magnification × 1) and the coordinate position of the positioning mark 70m. By using (ΔX1, ΔY1), the second X motor 21 and the second Y motor 22 (see Figs. 1 and 3 (a)) are controlled. Then, the controller 81 moves the X-ray radiator 10a by the second X motor 21 and the second Y motor 22 in the XY direction by ΔX1 and ΔY1 for a small amount so that the correction amount is canceled. The center position of the hole 65 (center position O of the display screen of the image display section 45), the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide (step). S15). In this case, since the optical axis L of the X-ray camera 10b and the center position of the microhole 65 are already coincident with the above adjustment, the second X motor 21 and the second Y motor 22 are already identical. The X-ray radiator 10a may be moved so that the radiation center of the X-ray radiator 10a coincides with the center position of the microhole 65.

In addition, the controller 81 controls the Z motor 43 at a predetermined coordinate position where the X-ray radiator 10a and the X-ray camera 10b are moved, so that the magnification of the X-ray camera 10b is increased. The setting is made (step S16).

Then, the controller 81 controls the magnification of the X-ray camera 10b in the storage unit 47 at the Z-direction position where the X-ray camera 10b moves in accordance with the magnification change (X-ray camera 10b). The third X motor 31 and the third Y motor 32 (see FIGS. 1 and 4) are controlled by using the correction amounts ΔX2 and ΔY2 stored in correspondence with the position in the Z direction. Then, the controller 81 moves the X-ray camera 10b by ΔX2 and ΔY2 for the XY direction by the third X motor 31 and the third Y motor 32 so that the correction amount is canceled. The center position of the hole 65, the radiation center of the X-ray radiator 10a, and the optical axis L of the X-ray camera 10b coincide with each other (step S17). Here, by the above adjustment, since the radiation center of the X-ray radiator 10a and the center position of the microhole 65 already correspond, the 3rd X motor 31 and the 3rd Y motor 32 make it possible. The X-ray camera 10b may be moved to match the center positions of the optical axis L and the microhole 65 of the X-ray camera 10b.

6, 12 (a) and 12 (b), the radiation center of the X-ray radiator 10a and the X-ray camera 10b at each magnification of the X-ray camera 10b. Position measurement is performed accurately in the state where the optical axis L of () is coincident.

As a result of the above-described position measurement operation, the controller 81 finishes the process when the position measurement at the predetermined magnification of the X-ray camera 10b is completed for the predetermined positioning mark 70m of the multilayer printed circuit board 70. Quit

As described above, according to the X-ray position measuring device 10 of the present embodiment, the X-ray radiator 10a and the X-ray camera 10b independently move along the XY coordinates (the surface of the multilayer printed board), respectively. In this case, by providing the position correction jig 61, it becomes possible to grasp the relative positions of each other where the X-ray radiator 10a and the X-ray camera 10b have moved. In the position measurement, the position of the X-ray camera 10b can be appropriately corrected so that the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide with each other. Therefore, as in the prior art, the structure of securing the positional accuracy by holding the X-ray camera 10b and the X-ray radiator 10a is eliminated by the U-shaped frame, and miniaturization of the entire X-ray position measuring apparatus is realized. In addition, when the X-ray radiator 10a and the X-ray camera 10b independently move along the XY coordinates, a high-precision XY transfer mechanism or a high rigidity mechanical housing is required to secure position accuracy. However, even if it does not have such a structure, high-precision position measurement is attained. Therefore, according to the X-ray position measuring device 10 of the present embodiment, it is possible to realize a small and low-cost X-ray position measuring device with high precision position measurement.

Moreover, according to the X-ray position measuring apparatus 10 of this embodiment, the X-ray camera 10b and X-ray radiator 10a which were provided so that the relative positional relationship of each other can be changed to Z direction are relatively relative to Z direction. It moves, and the result is measured by the position correction jig 61, and it becomes possible to confirm whether the coordinate of the center position of each other before and after a movement does not deviate from the XY direction. Therefore, high-precision position measurement is attained, without providing a high-precision Z-direction (up-down direction), a high rigid housing body, etc. In addition, when the X-ray radiator 10a and the X-ray camera 10b are movable along the XY coordinate, the X-ray radiator 10a is radiated along an Z direction at an arbitrary coordinate position on the XY coordinate. Since the position shift amount between the center and the optical axis L of the X-ray camera 10b can be measured and stored, and used for correction, high-precision position measurement is realized.

Moreover, according to the X-ray position measuring apparatus 10 of this embodiment, the radiation of the X-ray radiator 10a by thermal expansion of each part of the X-ray position measuring apparatus 10 by the heat which generate | occur | produces between position measuring operations. Even if a position shift between the center and the optical axis L of the X-ray camera 10b occurs, the positional deviation can be prevented from being deteriorated by appropriately correcting the position shift.

For example, a high voltage is applied between the cathode and the anode between position measurement operations in the X-ray tube, and hot electrons emitted from the filament collide with the target focal point to generate X-rays and heat to the target. . By this heat, each part of an anode thermally expands, and as a result, a target moves to a cathode side (for example, -X direction in this embodiment) along an X-ray tube axial direction. As a result of the movement of the target due to the thermal expansion of the anode, the position of the focus is also displaced in the -X direction by the same amount.

In this way, if the position of the focus causes a position shift, the radiation center of the X-ray radiator 10a causes a position shift and does not coincide with the optical axis L of the X-ray camera 10b. Precision deteriorates

However, according to the X-ray position measuring device 10 of the present embodiment, the radiation center and X-ray of the X-ray radiator originated from the thermal displacement of the cathode of the X-ray radiator 10a by providing the position correction jig 61. It is also possible to detect the position shift amount with the optical axis L of the camera and to correct it appropriately.

For example, at the predetermined timing after measuring the correction amount at each coordinate position of all the positioning marks 70m, the second using the position correction jig 61 for any of the positioning marks 70m is used. Position measurement of the X-ray projection image 102 is performed. And the correction amount obtained at this time is compared with the correction amount stored in the memory | storage part 47, and the presence or absence of the difference of two correction amounts is detected. When there is a difference between the two correction amounts, the correction amount at each coordinate position of all the positioning marks 70m is measured again, and the correction amount obtained after that is stored in the storage unit 47 as the correction amount. In the subsequent position measurement operation, the alignment between the X-ray radiator 10a and the optical axis L of the X-ray camera 10b is performed using the correction amount obtained thereafter.

According to this embodiment, since the position measurement process is performed as described above, even if the X-ray radiator 10a causes thermal displacement, measurement accuracy can be ensured. Therefore, it is unnecessary to take various countermeasures for suppressing thermal displacement of the X-ray radiator 10a. Therefore, the X-ray position measuring apparatus 10 enables high-precision position measurement and can reduce the cost.

Moreover, in the said embodiment, the measurement object was made into the multilayer printed circuit board 70 of a 7-layer structure. However, it is not limited to this, The measurement object may be a multilayer printed circuit board of 6 layers or less or 8 layers or more, and other processing object parts may be sufficient as it.

In the said embodiment, the position correction jig 61 was arrange | positioned between the X-ray radiator 10a and the X-ray camera 10b in the state where the relative position with the X-ray camera 10b was determined. However, it is not limited to this, You may arrange | position through the state in which the relative position with the X-ray radiator 10a was determined.

In the said embodiment, the magnification of this X-ray camera 10b was changed by moving the X-ray camera 10b with respect to the X-ray radiator 10a in the direction perpendicular | vertical to the workpiece | work mounting table 10c. However, it is not limited to this, It is also possible to set it as the structure which changes the magnification of the X-ray camera 10b by moving the X-ray radiator 10a with respect to the X-ray camera 10b.

In the above embodiment, the position correction jig 61 is detachably held in the fixing plate 62 having a rectangular flat plate shape and the holding opening 64 formed in the fixing plate 62, and the microhole ( And a disc jig 63 having 65) (see FIG. 3 (b)). However, the present invention is not limited to this, and instead of the disc jig 63, the plate body may be rotated with respect to a point provided at a predetermined position of the fixing plate 62 to have a minute hole 65 in the central portion in the width direction. In this plate body, when performing the positioning measurement of the positioning mark 70m, the position measurement of the 2nd X-ray projection image 102 is retracted from the lower side of the X-ray camera 10b so that the positioning may not be disturbed. In this case, positioning is performed at a predetermined position under the X-ray camera 10b where position measurement is possible.

In the said embodiment, the position which moves the X-ray radiator 10a and the X-ray camera 10b using the correction amount acquired beforehand for every coordinate position of the positioning mark 70m or every magnification of the X-ray camera 10b. Was corrected. However, the present invention is not limited to this, and it is also possible to correct the data itself obtained as a result of the position measurement based on the correction amount.

In the above embodiment, the position measurement by the X-ray position measuring device 10 makes the magnification of the X-ray camera 10b constant at all the positioning marks 70m, or the predetermined positioning mark ( 70 m) was performed by changing the magnification of the X-ray camera 10b. However, the present invention is not limited to this, and for each coordinate position of the positioning mark 70m, the magnification of the X-ray camera 10b is changed to a plurality of stages, and the positioning mark 70m with the magnification of the plurality of stages. The measured values of the coordinate position and the amount of position shift are stored as the correction amount. Then, the magnification is changed for each coordinate position of the positioning mark 70m while using the correction amount, the radiation center of the X-ray radiator 10a and the optical axis L of the X-ray camera 10b coincide with each other. It is also possible to do this.

In the above embodiment, at the time of position measurement by the X-ray position measurement apparatus 10, the controller 81 having a CPU as a computer executes the position measurement program stored in the storage unit 47. However, the present invention is not limited thereto, and the controller 81 may execute a program for position measurement recorded on a portable recording medium, and the controller 81 may execute a position measurement program transmitted via the Internet.

Various embodiments and modifications of the present invention can be made without departing from the broader spirit and scope of the present invention. In addition, embodiment mentioned above is only for demonstrating this invention, and does not limit the scope of the present invention.

10: X-ray position measuring device 10a: X-ray radiator
10b: X-ray camera 10c: Work wit table
10d: Base to 10e: Standing Plate
10f: groove 11: first X motor
13: first X moving member 14: second X moving member
15: Z moving body 21: the second X motor
22: 2nd Y motor 31: 3rd X motor
32: third Y motor 42: fourth Y motor
43: Z motor 44: servo motor group
45: image display section 46: X-ray radiator drive unit
47: memory 48: input
51: first orbit rail 52: second orbit rail
53: third orbit rail 54: fourth orbit rail
61: Jig for Position Correction 62: Plate for Fixing
63: disc jig 64: opening for holding
65: micro hole 70: multilayer printed circuit board
70m: positioning mark 70a: large diameter circle mark
70b: small-diameter one mark 71: prepreg (surface-side printed board)
73: prepreg (rear side printed board) 81: microcomputer
100: light receiving surface 101: first X-ray projection image
102: second X-ray projection image L: optical axis
O: center position of the display screen of the image display section 45
O ': the true center point of the second X-ray projection
O ": apparent center point on the second X-ray projection

Claims (7)

X-ray emitters and X-ray cameras;
A work placing table for placing a measurement object;
A first moving unit for moving the X-ray radiator along a corresponding workpiece placing table surface with respect to a measurement object on the workpiece placing table;
A second moving unit for moving the X-ray camera along the workpiece placing table surface with respect to the measurement object on the workpiece placing table;
An image display unit radiating from the X-ray radiator and projecting X-rays passing through the measurement object as a first X-ray projection image;
A position correction jig disposed between the X-ray radiator and the X-ray camera and configured to project the X-ray radiated from the X-ray radiator as a second X-ray projection image which can be positioned on the image display unit;
A control unit for controlling the first moving unit and the second moving unit to independently move the X-ray radiator and the X-ray camera with respect to the work mounting table; And
A storage unit for storing a positional shift amount between at least the reference position in the image display unit and the position of the second X-ray projection image as a correction amount;
The control unit,
First moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing position measurement on the measurement object;
At the position where the position measurement is performed, the position shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is used as a correction amount corresponding to the measurement position. First measurement storage means stored in the storage;
Second moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing the position measurement; And
At the position where the position measurement is performed, the first moving part and the second moving part are controlled on the basis of the correction amount so that the radiation center of the X-ray radiator and the optical axis of the X-ray camera are coincident with each other. And position measuring means for performing position measuring of the X-ray position measuring device. The apparatus according to claim 1, further comprising: a third moving part for changing an enlarged magnification of the X-ray camera by moving one of the X-ray radiator and the X-ray camera in a direction perpendicular to the work placing table,
The control unit includes: first magnification changing means for controlling the third moving unit to change the magnification of the X-ray camera;
At the position of the X-ray camera at which a predetermined magnification is realized, the positional shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is applied. Second measurement storage means stored in the storage unit as a correction amount corresponding to an enlarged magnification;
Second magnification changing means for controlling the third moving part to change the magnification of the X-ray camera; And
At the position of the X-ray camera at which a predetermined magnification is realized, the first moving part and the second moving part are controlled based on the correction amount to adjust the radiation center of the X-ray radiator and the optical axis of the X-ray camera. And X-ray position measuring device, further comprising second position measuring means for performing coincidence and performing position measurement of the measurement object. The X-ray position measuring apparatus according to claim 1 or 2, wherein the measurement object is a multilayer printed wiring board provided with a positioning mark at a position for performing position measurement. X-ray emitters and X-ray cameras;
A work placing table for placing a measurement object;
A first moving unit for moving the X-ray radiator along a corresponding workpiece placing table surface with respect to a measurement object on the workpiece placing table;
A second moving unit for moving the X-ray camera along the workpiece placing table surface with respect to the measurement object on the workpiece placing table;
An image display unit radiating from the X-ray radiator and projecting X-rays passing through the measurement object as a first X-ray projection image;
A position correction jig disposed between the X-ray radiator and the X-ray camera and configured to project the X-ray radiated from the X-ray radiator as a second X-ray projection image which can be positioned on the image display unit;
A control unit for controlling the first moving unit and the second moving unit to independently move the X-ray radiator and the X-ray camera with respect to the work mounting table; And
A storage unit storing at least a position shift amount between a reference position in the image display unit and a position in the second X-ray projection image as a correction amount
A position measuring method used in an X-ray position measuring apparatus having a
A first moving step of controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing position measurement on the measurement object;
At the position where the position measurement is performed, the position shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is used as a correction amount corresponding to the measurement position. A first measurement storage step stored in the storage unit;
A second moving step of controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing the position measurement; And
At the position where the position measurement is performed, the first moving part and the second moving part are controlled on the basis of the correction amount so that the radiation center of the X-ray radiator and the optical axis of the X-ray camera are coincident with each other. And a first position measuring step of performing position measurement of the X-ray position measuring apparatus. The third X-ray position measuring apparatus according to claim 4, wherein the X-ray position measuring device changes the magnification of the X-ray camera by moving one of the X-ray radiator and the X-ray camera in a direction perpendicular to the work placing table. Further provided with a moving part,
The method
A first magnification changing step of changing the magnification of the X-ray camera by controlling the third moving unit;
At the position of the X-ray camera at which a predetermined magnification is realized, the positional shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is applied. A second measurement memory step stored in the storage unit as a correction amount corresponding to an enlarged magnification;
A second magnification changing step of changing the magnification of the X-ray camera by controlling the third moving unit; And
At the position of the X-ray camera at which a predetermined magnification is realized, the first moving part and the second moving part are controlled based on the correction amount to adjust the radiation center of the X-ray radiator and the optical axis of the X-ray camera. And a second position measuring step of performing the position measurement of the measurement object simultaneously with the coincidence. X-ray emitters and X-ray cameras;
A work placing table for placing a measurement object;
A first moving unit for moving the X-ray radiator along a corresponding workpiece placing table surface with respect to a measurement object on the workpiece placing table;
A second moving unit for moving the X-ray camera along the workpiece placing table surface with respect to the measurement object on the workpiece placing table;
An image display unit radiating from the X-ray radiator and projecting X-rays passing through the measurement object as a first X-ray projection image;
A position correction jig disposed between the X-ray radiator and the X-ray camera and configured to project the X-ray radiated from the X-ray radiator as a second X-ray projection image which can be positioned on the image display unit;
A control unit for controlling the first moving unit and the second moving unit to independently move the X-ray radiator and the X-ray camera with respect to the work mounting table; And
A computer provided in the control unit of the X-ray position measuring apparatus having a storage unit for storing, as a correction amount, the positional shift amount between at least the reference position in the image display unit and the position of the second X-ray projection image,
First moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing position measurement on the measurement object;
At the position where the position measurement is performed, the position shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is used as a correction amount corresponding to the measurement position. First measurement storage means stored in the storage;
Second moving means for controlling the first moving part and the second moving part to move the X-ray radiator and the X-ray camera to a position for performing the position measurement; And
At the position where the position measurement is performed, the first moving part and the second moving part are controlled on the basis of the correction amount so that the radiation center of the X-ray radiator and the optical axis of the X-ray camera are coincident with each other. Position measuring means for performing position measurement
A program for position measurement of an X-ray position measuring device, characterized in that it functions as a. The third X-ray position measuring apparatus according to claim 6, wherein the X-ray position measuring device changes a magnification of the X-ray camera by moving one of the X-ray radiator and the X-ray camera in a direction perpendicular to the work place table. Further provided with a moving part,
The computer,
First magnification changing means for controlling the third moving part to change the magnification of the X-ray camera;
At the position of the X-ray camera at which a predetermined magnification is realized, the positional shift amount between the reference position on the image display unit and the position on the second X-ray projection image is measured, and the position shift amount is applied. Second measurement storage means stored in the storage unit as a correction amount corresponding to an enlarged magnification;
Second magnification changing means for controlling the third moving part to change the magnification of the X-ray camera; And
At the position of the X-ray camera at which a predetermined magnification is realized, the first moving part and the second moving part are controlled based on the correction amount to adjust the radiation center of the X-ray radiator and the optical axis of the X-ray camera. Second position measuring means for performing coincidence and performing position measurement of the measurement object
A program for position measurement of an X-ray position measurement apparatus, characterized by further functioning.

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