JP3635606B2 - Collimator setting device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a collimator setting device for positioning a collimator having a pair of opposed pinholes at a predetermined position with respect to an X-ray optical axis.
[0002]
[Prior art]
Conventionally, in an X-ray apparatus that analyzes a sample using X-rays, a collimator is often disposed on the X-ray incident side of the sample. This collimator is usually used to shape X-rays emanating from an X-ray focal point into a parallel X-ray beam having a small cross-sectional area. For example, considering a widely known Laue camera, a collimator 52 is disposed between the X-ray focal point F and the sample 51 as shown in FIG. The collimator 52 has a pair of pin holes 53a and 53b facing each other at both ends thereof.
[0003]
X-rays that diverge from the X-ray focal point F are formed into parallel X-ray beams having a small cross-sectional area by the pinholes 53 a and 53 b of the collimator 52, and then enter the sample 51 disposed behind the collimator 52. If the sample 51 is a powder sample, the Debye ring D forms an image on the photosensitive surface of the X-ray photosensitive film 54 by X-rays diffracted by the sample 51.
[0004]
The collimator 52 is not limited to the Laue camera as described above, and is used in an MDG (Micro Diffraction Goniometer) and other various X-ray apparatuses. Since this collimator 52 has a pair of pinholes 53a and 53b, it is sometimes called a double collimator. However, this type of double collimator has high directivity with respect to taking in X-rays. The axis X _C connecting 53b must exactly coincide with the X-ray optical axis X _R passing through the X-ray focal point F and the sample 51.
[0005]
[Problems to be solved by the invention]
In the conventional X-ray apparatus, when aligning the axis of the double collimator and the X-ray optical axis, first, the double collimator is disposed at a predetermined position on the X-ray optical axis, and the double collimator is viewed from the X-ray focal point. An X-ray counter is disposed at the rear position. Then, X-rays that diverge from the X-ray focal point are taken into an X-ray counter through a double collimator and the X-ray intensity is measured. The X-ray intensity to be measured changes depending on whether or not the pinhole of the double collimator is accurately on the X-ray optical axis, and the double collimator is positioned at an appropriate position where the X-ray intensity is strongest. It was judged to be a thing.
[0006]
However, as is well known, since X-rays are invisible light, during the above positioning operation, the operator knows exactly where the pinhole of the double collimator is located with respect to the X-ray optical axis. Therefore, the positioning work had to be done with total trial and error. As a result, the conventional positioning work related to the double collimator is a difficult work that takes a lot of time and effort.
The present invention has been made in view of the above-described problems, and an object of the present invention is to enable easy and quick positioning of a double collimator at an accurate position with respect to an X-ray optical axis.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, a collimator setting apparatus according to the present invention is a collimator setting apparatus for positioning a collimator having a pair of opposed pinholes at a predetermined position with respect to an X-ray optical axis. A setting collimator cylinder having a hole and a long hole at the other end, collimator cylinder support means for rotatably supporting the setting collimator cylinder around its axis, and a pinhole of the setting collimator cylinder And a collimator tube tilting means for tilting and moving the collimator tube as a center.
[0008]
According to this collimator setting device, an elongate hole is provided at one end of the setting collimator cylinder, and the setting collimator cylinder can be rotated around its axis, so that the setting collimator cylinder can be rotated around its axis. When X-rays are emitted from the X-ray focal point toward the X-ray counter, the X-rays pass through the slot when the slot that rotates according to the rotation of the setting collimator tube crosses the X-ray optical axis. X-rays are detected by being taken into the line counter. By observing the rotating direction of the setting collimator cylinder and the angular position of the elongated hole at this time, it is possible to know in which direction the axis of the setting collimator cylinder is shifted with respect to the X-ray optical axis. Based on this, the position of the setting collimator cylinder with respect to the X-ray optical axis can be easily and quickly determined.
[0009]
In the above configuration, the collimator tube support means for rotatably supporting the setting collimator tube can be formed by an arbitrary structure. For example, a support structure of a system that supports the outer peripheral surface of the setting collimator tube at three points. Can be adopted. According to this three-point support method, the setting collimator tube can be stably supported at a fixed position.
[0010]
The collimator tube tilting means can be configured using, for example, a structure in which the setting collimator tube is tilted and moved in each of two axial directions orthogonal to the X-ray optical axis. If the setting collimator tube is tilted and moved in two orthogonal directions in this way, the collimator tube can be tilted to a free position in three dimensions.
[0011]
In addition to the collimator tube support means and the collimator tube tilting means, the collimator setting device of the present invention may be provided with collimator tube translation means for translating the entire setting collimator cylinder with respect to the X-ray optical axis. it can. The collimator tube parallel moving means is, for example, for translating the entire setting collimator tube vertically or horizontally in order to position a pinhole provided at one end of the setting collimator tube on the X-ray optical axis. As long as the X-ray optical axis can be moved with respect to the setting collimator tube, the collimator tube parallel moving means is not necessarily provided.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
First, before describing the collimator setting apparatus according to the present invention, an X-ray apparatus that requires such setting work for the collimator will be described. FIG. 1 shows a Laue camera as an example of such an X-ray apparatus. This Laue camera includes an X-ray focal point F that emits X-rays, a double collimator 2 supported by a collimator tube support device 1, a sample support table 4 that supports a sample 3, an X-ray photosensitive film 6, and an X-ray photosensitive film. And a line counter 7. The axis X _C of the double collimator 2 is positioned so as to exactly coincide with the X-ray optical axis X _R passing through the X-ray focal point F and the sample 3.
[0013]
Double collimator 2 has a pair of pin holes 8a and 8b facing each other at both ends on the axis X _C, X-rays diverging emitted from the X-ray focal point F is the cross-sectional area by these pinholes 8a and 8b Is incident on the sample 3 after being formed into a small parallel X-ray beam. If the sample 3 is a powder sample, the Debye ring D forms an image on the photosensitive surface of the X-ray photosensitive film 6 by the X-rays diffracted by the sample 3. By observing this Debye ring D, it is possible to visually determine the size of crystal grains, the presence or absence of lattice distortion, the presence or absence of orientation, and the like.
[0014]
In the X-ray measurement as described above, the axis X _C of the double collimator 2 must be exactly matched to the X-ray optical axis X _R. In the present embodiment, the collimator 2 is positioned by the following operation.
First, the collimator tube support device 1 includes both the holders 9a and 9b that support both ends of the collimator 2, the tilting drive mechanism 11 that moves the holder 9a near the X-ray focal point F, and both the holders 9a and 9b. And a collimator cylinder parallel moving mechanism 12 that moves in an integrated state. The holder 9b on the side close to the sample 3 is set so as to support the position directly below the pinhole 8b. Further, the tilt drive mechanism 11 reciprocates linearly moved holder 9a along each axis of the X-axis and Y-axis which are two orthogonal axes perpendicular to the X-ray optical axis X _R. If the other end of the collimator 2 is linearly moved in the X axis direction and / or the Y axis direction by the tilting drive mechanism 11 with the end of the collimator 2 near the sample 3 supported by the holder 9b, the collimator 2 is moved. The pinhole 8b on the side close to the sample 3 can be tilted and moved three-dimensionally.
[0015]
On the other hand, the collimator cylinder parallel moving mechanism 12 can simultaneously translate both the holder 9a and the holder 9b in the X axis direction and / or the Y axis direction in an integrated state. The tilting drive mechanism 11 and the collimator cylinder parallel moving mechanism 12 may be a manual mechanism using a precision moving mechanism such as that used in a micrometer for minute dimension measurement, or a pulse motor or the like. An automatic mechanism using a precision power source may be used.
[0016]
As shown in FIG. 8, the holders 9 a and 9 b include a holder block 13 having a right-angled cut portion and a plate spring 14 fixed to the holder block 13. When the collimator 2 is mounted on the holders 9a and 9b, the collimator 2 is pushed into the right-angled cut portion of the holder block 13 while spreading the leaf spring 14 from above the holder block 13 as indicated by an arrow A. Then, the outer peripheral surface of the collimator 2 is supported at three points by the two wall surfaces of the right-angled cut portions of the holder blocks 9a and 9b and the leaf spring 14 that has returned and moved as indicated by the arrow B. With this three-point support structure, the collimator 2 can freely rotate about the axis X _C as indicated by an arrow C.
[0017]
In performing the positioning work on the collimator 2, first, as shown in FIG. 2, the setting single collimator cylinder 18 having the pinhole 16 at one end and the open end 17 at the other end is inserted into the holders 9a and 9b of the collimator cylinder support device 1. Attach to. At this time, the sample 3 and the X-ray photosensitive film 6 shown in FIG. 1 are not yet placed on the X-ray optical axis X _R , and the X-ray counter 7 is arranged on the X-ray optical axis X _R. The In this state, the collimator cylinder parallel movement mechanism 12 is operated to move the entire collimator cylinder 18 in the X axis direction and / or the Y axis direction, measure the X-rays by the X-ray counter 7, and measure the intensity of the X-rays. The movement of the collimator tube 18 is stopped at the place where the pressure becomes strongest. Thereby, the optimal position of the pinhole 16 is specified. However, in this state, it is not known whether the axis X _C of the collimator cylinder 18 exactly matches the X-ray optical axis X _R. That is, the axis X _C of the collimator cylinder 18 may be inclined with respect to the X-ray optical axis X _R.
[0018]
Therefore, the positioning work of the axis X _C as the next step. That is, as shown in FIG. 3, a setting collimator cylinder 21 having a pinhole 16 at one end and a long hole 19 at the other end is replaced with a single collimator cylinder 18 in FIG. Attach to 9b. At this point, the positioning operation using the single collimator tube 18 shown in FIG. 2 has been completed, the pin hole 16 of the setting for the collimator tube 21 is correctly positioned on the X-ray optical axis X _R. Reference numeral 22 denotes a mark indicating the position of the long hole 19.
[0019]
At this time, if the center of the end of the setting collimator cylinder 21 on the long hole 19 side is exactly on the X-ray optical axis X _R , the X-ray counter 7 receives the X-ray with the strongest intensity. At this point in time when the positioning operation has not been completed, the collimator tube 21 normally has an inclination with respect to the X-ray optical axis X _R , so that the X-ray emitted from the X-ray focal point F is a long hole. 19 and the pinhole 16 cannot pass through, and as a result, no X-rays appear in the X-ray counter 7.
[0020]
For example, when the setting collimator cylinder 21 is viewed from the direction of arrow E, the axis X _C of the setting collimator cylinder 21 is deviated from the X-ray optical axis X _R as shown in FIG. . Of course, since the X-ray optical axis X _R is not visible to the operator, at this point, the operator can confirm that the axis X _C of the setting collimator cylinder 21 is shifted from the X-ray optical axis X _R. I know, but I don't know how much it's moving in which direction.
[0021]
In this state, the operator first rotates the collimator tube 21 in the clockwise and / or counterclockwise directions about the axis X _C as indicated by the arrow G. At this time, when the long hole 19 that rotates together with the collimator cylinder 21 moves to the X-ray optical axis X _R , the X-ray passes through both the long hole 19 and the pin hole 16 and the X-ray counter 7 (FIG. 3). Detects it. Thereby, the operator knows that the long hole 19 has arrived on the X-ray optical axis X _R and stops the rotation of the collimator cylinder 21. This state is shown in FIG. In FIG. 4, depending on whether the collimator cylinder 21 is rotated in the clockwise direction or the counterclockwise direction, the operator knows which side of the X-ray optical axis X _R is shifted from the cylinder axis X _C. it can.
[0022]
In the state of FIG. 5, since the long hole 19 has been lowered obliquely downward, the operator can determine that the X-ray optical axis X _R is below the cylinder axis X _C. Therefore, the operator lowers the holder 9a as indicated by the arrow H in order to correct it. Then, X-rays are hidden from the X-ray counter 7 when the long hole 19 deviates from the X-ray optical axis X _R. At this time, the operator rotates the collimator tube 21 as indicated by an arrow J and detects X-rays again by the X-ray counter 7. By repeating this operation, as shown in FIG. 6, the positions of the holder 9a and the collimator tube 21 are adjusted until the long hole 19 becomes horizontal. Whether or not the long hole 19 is in the horizontal state as shown in FIG. 6 can be determined by whether or not the X-ray counter 7 can always detect X-rays when the holder 9a is reciprocated in the X-axis direction.
[0023]
Thereafter, if the holder 9a is linearly moved in the X-axis direction and the collimator cylinder 21 is carried to the boundary portion where the X-ray counter 7 can detect or cannot detect the X-ray, as shown in FIG. _C and the X-ray optical axis X _R can be exactly matched. After the axis X _C of the collimator cylinder 21 is thus exactly aligned with the X-ray optical axis X _R , the setting collimator cylinder 21 is removed from the holders 9a and 9b, that is, the collimator cylinder support device 1, and instead shown in FIG. in the double collimator 2 for measurement if attached to the collimator barrel support apparatus 1, it is possible to match the axis X _C of the double collimator 2 accurately to the X-ray optical axis X _R.
[0024]
As described above, when the positioning collimator cylinder 21 having the pinhole 16 at one end and the long hole 19 at the other end is used for the positioning work related to the measurement collimator, the setting with respect to the X-ray optical axis X _{R is} performed during the work. The direction of displacement of the axis X _C of the collimator cylinder 21 can be determined easily and quickly. Therefore, positioning with respect to the collimator 2 can be performed extremely easily, quickly and accurately compared to the conventional positioning operation by trial and error. It can be carried out.
[0025]
The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications can be made within the scope of the invention described in the claims.
For example, the collimator setting apparatus according to the present invention is limited to use only in a Laue camera as shown in FIG. 1, and is applicable to any X-ray apparatus that needs to form X-rays into a parallel beam with a small cross-sectional area. It can also be applied to. Further, the mechanism for moving the setting collimator cylinder in parallel or tilting is not limited to the mechanism shown in FIG. 1, and any other mechanism can be used.
[0026]
【The invention's effect】
According to the collimator setting apparatus of the first aspect, the setting collimator cylinder is provided with an elongated hole at one end, and the setting collimator cylinder can be rotated around its axis. Which direction is deviated with respect to the X-ray optical axis can be easily and clearly known, and therefore the position of the collimator with respect to the X-ray optical axis can be easily, quickly and accurately positioned.
[0027]
According to the collimator setting device of the second aspect, the setting collimator cylinder can be stably rotated around its axis.
[0028]
According to the collimator setting device of the third aspect, the setting collimator cylinder can be tilted and moved three-dimensionally easily and with high accuracy.
[0029]
According to the collimator setting device of the fourth aspect, since it is not necessary to move the X-ray apparatus side at all when performing the positioning work on one pinhole of the double collimator, the positioning work is performed simply, accurately and safely. be able to.
[0030]
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of an X-ray apparatus requiring a collimator setting device according to the present invention.
FIG. 2 is a perspective view showing an initial process of collimator positioning work performed using the collimator setting device according to the present invention.
FIG. 3 is a perspective view showing an embodiment of a collimator setting device according to the present invention.
4 is a front view showing one process of positioning work using the apparatus of FIG. 3; FIG.
5 is a front view showing another process of the positioning operation subsequent to FIG. 4. FIG.
6 is a front view showing still another process of the positioning operation subsequent to FIG. 5. FIG.
7 is a front view showing still another process of the positioning operation subsequent to FIG. 6. FIG.
FIG. 8 is a perspective view showing a main part of FIG. 3;
FIG. 9 is a perspective view showing a conventional collimator positioning operation.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Collimator cylinder support apparatus 2 Double collimator 3 Sample 7 X-ray counter 8a, 8b Pinhole 9a, 9b Holder 11 Tilt drive mechanism (collimator cylinder tilting means)
12 Collimator cylinder parallel movement mechanism 16 Pin hole 17 Open end 18 Setting single collimator cylinder 19 Slot 21 Setting collimator cylinder 22 Mark D Debyling F X-ray focus X _C Collimator axis X _R X-ray optical axis

Claims (4)

In a collimator setting device for positioning a collimator having a pair of opposed pinholes at a predetermined position with respect to the X-ray optical axis,
A collimator tube for setting with a pin hole at one end and a long hole at the other end;
Collimator tube support means for rotatably supporting the setting collimator tube around its axis,
A collimator setting device comprising collimator tube tilting means for tilting and moving the setting collimator tube around the pinhole of the setting collimator tube. 2. The collimator setting apparatus according to claim 1, wherein the collimator tube support means supports the setting collimator tube at three points on the outer peripheral surface thereof. 3. The collimator setting device according to claim 1, wherein the collimator tube tilting means tilts and moves the setting collimator tube in each of two axial directions orthogonal to the X-ray optical axis. In the collimator setting device according to at least one of claims 1 to 3,
A collimator setting device comprising collimator cylinder parallel moving means for translating the entire setting collimator cylinder with respect to the X-ray optical axis.

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