JPH02221847A - Optical axis adjusting method and optical axis adjusting jig of x-ray diffraction apparatus for micropart - Google Patents

Abstract

PURPOSE:To allow safe and exact optical axis adjustment by adjusting the position of a collimator in accordance with X-ray intensity by using a jig having an edge. CONSTITUTION:A shielding cover 6 is mounted to a position sensitive type proportional counter tube 1 of a curved type and the counter tube 1 is rotated by about 3 deg. clockwise from an ordinary detection position. An X-ray is then emitted from the collimator 4 and is measured by the counter tube 1 before the jig 5 is mounted to a sample holder 2. Then, the jig 5 is mounted to the holder 2. The holder 2 is kept inclined at 20 deg. angle from a perpendicular axis. The jig 5 is so positioned that its edge extends in the forward and backward direction of the plane of the figure. A microscope 3 is fixed in a 55 deg. angle position from the perpendicular axis and the edge of the jig 5 is observed by this microscope 3. The X-ray is emitted from the collimator 4 and the X-ray intensity is measured by the counter tube 1. Further, the vertical position of the collimator 4 is so adjusted that the X-ray intensity of this time decreases to a half. The positioning of the collimator 4 in the vertical position thereof is completed in this way. The holder 2 is phi-rotated by 90 deg. to adjust the position of the collimator 4 in the forward and backward direction of the plane of the figure.

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a microscopic part X for measuring a microscopic part of a sample by X-ray diffraction.
The present invention relates to an optical axis adjustment method for a linear diffraction device and an optical axis adjustment jig used in this method.

[Prior Art] A microscopic X-ray diffractometer uses a collimator because it is necessary to accurately irradiate X-rays onto a microscopic region of a sample.

In order to accurately adjust the position of this collimator, a fluorescent material for optical axis adjustment is used. FIG. 5 shows a conventional optical axis adjustment jig. This tip axis adjustment jig 21 is used by being attached to a sample holder. A fluorescent material 22 with a diameter of 0.03 mm is embedded in the center of the tip surface of this jig 21. When X-rays hit this fluorescent material, fluorescence is emitted, which allows the collimator to be positioned.

The optical axis adjustment method using this jig 21 is as follows. First, this jig 21 is attached to a sample holder. Then, the fluorescent material 2 of this jig 21 is placed in the center of the field of view of the microscope.
Adjust the position of the sample holder so that 2 is placed. In addition,
The center of the field of view of the microscope always coincides with the three-axis rotation center of the sample holder. Next, the collimator emits X-rays, and the position of the collimator is two-dimensionally adjusted in a plane perpendicular to the optical axis so that the X-rays hit the fluorescent substance 21.

[Problem to be solved by the invention] The conventional optical axis adjustment method described above has the following drawbacks.

(a) Since the position of the collimator is adjusted by checking the light emitted from the fluorescent substance, it relies on the operator's eyes, and the accuracy of optical axis adjustment is poor.

(b) Workers must look through the microscope and adjust the collimator while emitting X-rays, which is dangerous as they come close to the X-rays.

The present invention aims to eliminate such drawbacks, and its purpose is to provide a method and a jig for adjusting the optical axis of a microscopic X-ray diffraction device safely and accurately. .

[Means for Solving the Problems and Their Effects] In order to achieve the above object, the optical axis adjustment method according to the present invention has the following steps.

(a) A step of attaching an optical axis adjustment jig having an edge to a rotatable sample holder.

(b) adjusting the position of the sample holder so that the edge crosses the center of the field of view of the microscope;

(c) A step of emitting X-rays from the collimator and passing near the edge of the optical axis adjustment jig, and detecting the X-ray intensity at this time.

(d) Position the collimator in a direction perpendicular to the optical axis so that the X-ray intensity obtained in step (C) above is half the X-ray intensity when the X-rays from the collimator are directly detected. Adjustment stage.

(e) Rotate the sample holder 90 degrees, and then
) (c) Repeating step (d) to adjust the position of the collimator also in a direction perpendicular to the collimator position adjustment direction in step (d).

The X-rays are partially blocked at the edge of the optical axis adjustment jig and reach the detector. Therefore, if the position of the collimator is adjusted so that the X-ray detection intensity is halved, the optical axis of the X-rays at this time will be exactly on the edge of the jig.

This makes it possible to adjust the position of the collimator in one dimension within a plane perpendicular to the optical axis. By rotating the sample holder 90 degrees and making similar adjustments, the two-dimensional position adjustment of the collimator is completed.

In addition, if a curved position-sensitive proportional counter tube is used as the X-ray detector of a microscopic X-ray diffraction device, when adjusting the optical axis, place a It is preferable to cover the cover with a scattered X-ray blocking cover having holes formed therein.

Further, the optical axis adjustment jig according to the present invention is used by being attached to a rotatable sample holder of a microscopic X-ray diffraction apparatus, and this jig has an edge and is elastically deformable. It has a displacement part and a fine adjustment screw that contacts the displacement part and finely adjusts the position of the edge of the displacement part.

When this fine adjustment screw is screwed in, the displacement part deforms and the edge moves slightly, allowing the edge to be correctly positioned in the center of the field of view of the microscope.

[Example] Next, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side view of essential parts showing an example of a microscopic X-ray diffraction apparatus for carrying out the method of the present invention.

This microscopic X-ray diffraction device uses a curved position-sensitive proportional counter 1 (hereinafter referred to as PSPC) as an X-ray detector.
is used. This diffraction device also includes a sample holder 2 that can rotate on three axes, a microscope 3 for observing minute parts of the sample, a collimator 4 for accurately irradiating the minute parts of the sample with X-rays, and an X-ray a source (not shown). When adjusting the optical axis, an optical axis adjustment jig 5 is attached to the sample holder 2, and a scattered X-ray blocking cover 6 is attached to the detection window of the curved PSPCI.
Attach.

FIG. 2 shows details of the optical axis adjustment jig 5. This jig 5 has the shape of a cylinder cut in half, and this half cylinder part has a groove 54 cut in the vertical direction, and a thin displacement part 51.
and a thick half-moon portion 55. The displacement part 51 has an upper part 511 whose side surface is located on the center line of the jig 51.
And the lower part 51 is slightly recessed than the upper part 511.
It consists of 2. A tip member 52 made of Au is integrally fixed to the upper part 511. The edge 53 of the tip member 52 is
It is located on the center line of the jig 5. The half-moon portion 55 has a screw hole into which a fine adjustment screw 56 is screwed (see also FIG. 1). The tip of the fine adjustment screw 56 contacts the displacement portion 51, and when the fine adjustment screw 56 is screwed in, the displacement portion 51 is displaced toward the front in FIG. Fine adjustment screw 5
When 6 is retracted, the displaced portion 51 returns to its original state due to its own elasticity. Edge 53 is therefore adjustable in position in the direction of arrow 58. This jig 5 is attached to the sample holder 2 by a shaft 57.

FIG. 3 is a perspective view of a portion of the scattered X-ray blocking cover 6. FIG. A hole 61 with a diameter of about 5 to 10 mm is formed in this cover 6, and X-rays can pass through this hole 61. X-rays that reach areas other than the hole 61 during optical axis adjustment are scattered X-rays,
This is all blocked by cover 6 and the curved PSPCI
does not reach.

Next, a method for adjusting the optical axis of this micro X-ray diffraction device will be explained. In FIG. 1, first, the scattered X
Attach the line interruption cover 6. And curved PSPC
Rotate I clockwise in the drawing by about 3 degrees from the normal detection position. The reason is as follows. Curved PSPCI
has a detection area of about 180 degrees, but in a normal arrangement, the position facing the collimator 4 is at the extreme edge of the detectable area. Therefore, in order to ensure X-ray detection during optical axis adjustment, a detection area about 3 degrees inside is used in this way.

Next, before attaching the jig 5 to the sample holder 2, X-rays are emitted from the collimator 4 and measured by the curved PSPCI. Let the X-ray intensity at this time be I.

Next, the jig 5 is attached to the sample holder 2. The sample holder 2 is tilted at an angle of 20 degrees from the vertical axis. and,
The edges of the jig 5 are made to extend in the front-rear direction of the paper. The microscope 3 is fixed at an angular position of 55 degrees from the vertical axis, and the edge of the jig 5 is observed using this microscope 3. FIG. 4 shows the field of view 31 of the microscope 3. There is a crosshair 32 in the visual field 31, and the intersection A of the crosshairs is the center of the visual field 31. The position of the sample holder 2 is adjusted so that the edge 53 of the jig crosses this intersection A.

Note that the intersection point A of the field of view 31 of the microscope and its depth of focus are positioned at the center of the three-axis rotation of the sample holder.

Next, the collimator 4 emits X-rays to form a curved PSP.
Measure X-ray intensity with CI. Then, the vertical position of the collimator 4 is adjusted so that the X-ray intensity at this time becomes 1/2. That is, the upper half of the X-rays emitted from the collimator 4 is blocked by the edge of the jig 5, and only the lower half reaches the curved shape pspc1. This completes the vertical positioning of the collimator 4.

Next, the sample holder 2 is rotated φ by 90 degrees so that the edge of the jig 5 extends in the left-right direction in FIG. Then, the same operation as described above is performed to adjust the position of the collimator 4 in the front-rear direction of the paper.

By the above operations, two parts of the collimator 4 are aligned in the plane perpendicular to the optical axis.
Dimension position adjustment is complete.

In the above-described embodiment, a jig having a fine adjustment screw is used, but the fine adjustment screw does not necessarily need to be used to carry out the optical axis adjustment method of the present invention. That is, a jig without the groove 54 or fine adjustment screw 56 shown in FIG. 2 can also be used. In this case, the jig is simply the edge 53.
It is sufficient to have the following. When using such a jig, the XY adjustment mechanism attached to the sample holder 2 shown in Figure 1 allows the jig to be adjusted in two-dimensional directions within a plane perpendicular to the axis of the sample holder. This allows the edge of the jig to be centered in the field of view of the microscope.

[Effects of the Invention] As explained above, the optical axis adjustment method according to the present invention uses a jig with edges to adjust the position of the collimator based on the X-ray intensity, and therefore has the following effects.

(a) Since the position of the collimator is adjusted based on the X-ray intensity, the accuracy of optical axis adjustment is improved compared to the conventional observation of fluorescence by an operator.

(b) Workers do not have to look into the microscope when X-rays are being emitted, making it safer.

(c) The position of the collimator can be adjusted based on the X-ray intensity, making it easy to automate optical axis adjustment.

Further, the optical axis adjustment jig according to the present invention has an extremely simple structure, as the position of the edge can be adjusted simply by elastically deforming the displacement portion using the fine adjustment screw.

[Brief explanation of the drawing]

FIG. 1 is a side view of essential parts showing an example of a microscopic X-ray diffraction apparatus for carrying out the method of the present invention, and FIG. 2 is a perspective view of an embodiment of the optical axis adjustment jig according to the present invention. FIG. 3 is a perspective view of a portion of the scattered X-ray blocking cover, FIG. 4 is an explanatory view showing the field of view of the microscope, and FIG. 5 is a perspective view of a conventional optical axis adjustment jig. 1... Curved position-sensitive proportional counter tube 2... Sample holder 3... Microscope 4... Collimator 5... Optical axis adjustment jig 51... Displacement part 53... Edge 56 ... Fine adjustment screw 6 ... Scattered X-ray cover 61 ... Hole

Claims (3)

[Claims] (1) A method for adjusting the optical axis of a microscopic X-ray diffraction device having the following steps. (a) A step of attaching an optical axis adjustment jig having an edge to a rotatable sample holder. (b) adjusting the position of the sample holder so that the edge crosses the center of the field of view of the microscope; (c) A step of emitting X-rays from the collimator and passing near the edge of the optical axis adjustment jig, and detecting the X-ray intensity at this time. (d) Position the collimator in a direction perpendicular to the optical axis so that the X-ray intensity obtained in step (c) above is half the X-ray intensity when the X-rays from the collimator are directly detected. Adjustment stage. (e) Rotate the sample holder 90 degrees, and then
)(c) Repeating step (d) to adjust the position of the collimator also in a direction perpendicular to the collimator position adjustment direction in step (d). (2) The X-ray detector of the microscopic X-ray diffraction device is a curved position-sensitive proportional counter tube, and when adjusting the optical axis, a hole for X-ray passage is made in the detection window of this counter tube. 2. The method of claim 1, further comprising a formed scattering X-ray blocking cover. (3) In an optical axis adjustment jig that can be attached to a rotatable sample holder of a microscopic X-ray diffraction device, there is a displaceable part that has an edge and is elastically deformable, and a displaceable part that comes into contact with the displaceable part. An optical axis adjustment jig characterized by having a fine adjustment screw for finely adjusting the position of an edge.