JP2015137907A - Back reflection x-ray analysis device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an X-ray analysis device which can set camera length by avoiding interference with a measuring object even in a case in which irregularities exist on the surface shape of the measuring object.SOLUTION: A back reflection X-ray analysis device comprises: an X-ray tube 1 which emits an X-ray to a sample 3; an imaging plate 2 which can detect a toric diffraction image formed by a diffraction X-ray by receiving the diffraction X-ray diffracting on the surface of the sample 3 when the X-ray is made incident on the sample 3; and camera length variable setting means which can set the camera length by selecting any one from a plurality of prescribed distances in a case of setting the camera length prescribed with a distance from an X-ray passage hole 5 of the imaging plate to a laser irradiation position O of the sample 3 in the optical axis direction of the X-ray emitted from the X-ray tube 1. The camera length variable setting means is constituted by using a distance sensor mechanism 10 of a triangular range-finding system.

Description

  The present invention relates to a back reflection X-ray analysis apparatus including an X-ray detector that irradiates a measurement object with X-rays and receives X-rays diffracted by the measurement object.

  Conventionally, by irradiating a measurement object with X-rays and receiving the X-ray diffracted by the measurement object with an X-ray detector, an annular diffraction image formed on the X-ray detector (hereinafter referred to as “diffraction ring”). Also known is a back-reflection X-ray analysis apparatus for measuring "." The “back reflection” described here refers to a reflection having a black angle larger than 45 degrees during Bragg diffraction of X-rays. The back-reflection X-ray analyzer is used to measure the residual stress by analyzing the shape of the diffraction ring, quantitative analysis of the crystal phase from the intensity ratio of multiple diffraction rings, crystal orientation analysis and crystal structure to measure Laue spots Some perform analysis.

  In general, the back reflection X-ray analyzer is large in size and difficult to carry. Therefore, in recent years, a back reflection X-ray analysis apparatus that has been reduced in size and weight has been proposed (see Patent Document 1). In this back reflection X-ray analyzer, an X-ray emitter, an X-ray detector, and the like are housed in a housing with a handle to facilitate transport of the back reflection X-ray analyzer.

JP 2013-113737 A

However, the conventional back reflection X-ray analyzer described in Patent Document 1 has the following drawbacks.
That is, in general, in the back reflection X-ray analyzer, when X-ray analysis is performed using an X-ray detector, the distance from the X-ray detector to the measurement object is set to a predetermined specified distance ( Hereinafter, it is also referred to as “camera length”). At that time, the conventional antireflection X-ray analyzer has only one camera length applicable to X-ray analysis, that is, the camera length is fixed, so that the desired camera length can be obtained depending on the measurement environment. There were cases where it could not be set. Specifically, for example, when a convex portion exists on a part of the surface of the measurement object, a part of the housing described above interferes (contacts) with the convex part of the measurement object, and the desired object is obtained. The camera length could not be set.

  Incidentally, the reason for setting the camera length in accordance with the prescribed (known) distance in the back reflection X-ray analyzer is as follows. First, the size (diameter) of the diffraction ring formed in the X-ray detector varies depending on the camera length. Specifically, even if the X-ray diffraction angle diffracted on the surface of the object to be measured is the same, if the measurement is performed under a short camera length, the detected diffraction ring becomes small and the long camera length When the measurement is performed with, the detected diffraction ring becomes larger. For this reason, if the camera length is deviated from a specified distance or the camera length is unknown, even if the diffraction ring can be detected, accurate X-ray analysis (stress measurement, etc.) is performed based on this. I can't do that.

  A main object of the present invention is to provide an X-ray analyzer capable of setting the camera length while avoiding interference with a measurement object even when the surface shape of the measurement object is uneven.

The first aspect of the present invention is:
An X-ray emitting unit that emits X-rays toward the measurement object;
An annular diffraction formed by the diffracted X-ray by receiving the diffracted X-ray diffracted by the measurement object when the X-ray emitted from the X-ray emission part is incident on the measurement object. An X-ray detector capable of detecting an image;
When setting the camera length defined by the distance from the X-ray detector to the measurement object in the direction of the optical axis of the X-rays emitted from the X-ray emission part, the first camera length corresponding to the first camera length is set. One of a plurality of specified distances including a specified distance and a second specified distance corresponding to a second camera length different from the first camera length can be selected and set. Camera length variable setting means;
A back reflection X-ray analyzer characterized by comprising:

The second aspect of the present invention is:
The camera length variable setting means is configured to use a triangulation distance sensor mechanism. The back reflection X-ray analysis apparatus according to the first aspect, wherein the camera is variable.

The third aspect of the present invention is:
The distance sensor mechanism is
A laser emitting section for emitting a visible laser to be irradiated to the measurement object;
A laser receiving unit that receives a visible laser beam emitted from the laser emitting unit and reflected by the measurement object;
The back reflection X according to the second aspect, wherein the laser light receiving position of the laser light receiving unit is changed according to a distance from the X-ray detector to the measurement object. It is a line analyzer.

The fourth aspect of the present invention is:
An optical axis when the measurement object is irradiated with the visible laser emitted from the laser emitting unit, and an optical axis when the measurement object is irradiated with the X-ray emitted from the X-ray emitting unit Is set to be coaxial, The back reflection X-ray analysis apparatus according to the third aspect, characterized in that:

According to a fifth aspect of the present invention,
An optical path converting means for converting the optical path of the visible laser emitted from the laser emitting section so that the optical axis of the visible laser is coaxial with the X-ray emitted from the X-ray emitting section;
Advancing / retreating support means for supporting the optical path conversion means so as to be movable back and forth with respect to the optical path of the X-rays emitted from the X-ray emitting section;
The back reflection X-ray analyzer according to the fourth aspect, characterized in that

The sixth aspect of the present invention is:
An optical axis when the measurement object is irradiated with the visible laser emitted from the laser emitting unit, and an optical axis when the measurement object is irradiated with the X-ray emitted from the X-ray emitting unit Are set so as to intersect with each other. The back reflection X-ray analyzer according to the third aspect.

The seventh aspect of the present invention is
The back reflection X-ray analyzer according to the sixth aspect, further comprising a sensor moving mechanism that moves a position where the X-ray and the visible laser intersect by moving the distance sensor mechanism. is there.

The eighth aspect of the present invention is
The back-reflection X-ray analysis apparatus according to the seventh aspect, wherein the sensor moving mechanism moves the distance sensor mechanism linearly.

The ninth aspect of the present invention provides
The back-reflection X-ray analyzer according to the seventh aspect, wherein the sensor moving mechanism rotates the distance sensor mechanism.

  According to the present invention, it is possible to set the camera length while avoiding interference with the measurement object even when the surface shape of the measurement object has irregularities.

It is a perspective view which shows an example of a structure of the back surface reflection X-ray analyzer which can apply this invention. 1 is a perspective view showing a schematic configuration of a back reflection X-ray analysis apparatus according to a first embodiment of the present invention. It is a figure explaining the structure of the principal part of the back surface reflection X-ray analyzer which concerns on the 1st Embodiment of this invention. In the 1st Embodiment of this invention, it is a figure which shows the positional relationship of each part at the time of installing the back reflection X-ray-analysis apparatus close to a sample, and when installing apart. It is a figure explaining the structure of the principal part of the back reflection X-ray analyzer which concerns on the 2nd Embodiment of this invention. In the 2nd Embodiment of this invention, it is a figure which shows the positional relationship of each part at the time of installing a back reflection X-ray analyzer close to a sample. In the 2nd Embodiment of this invention, it is a figure which shows the positional relationship of each part at the time of installing a back surface reflection X-ray analyzer away from a sample. It is a figure explaining the structure of the principal part of the back reflection X-ray analyzer which concerns on the 3rd Embodiment of this invention. It is a figure which shows the positional relationship before and behind the rotational movement of the distance sensor mechanism by a sensor moving mechanism. In the 3rd Embodiment of this invention, it is a figure which shows the positional relationship of each part at the time of installing a back reflection X-ray analyzer close to a sample. In the 3rd Embodiment of this invention, it is a figure which shows the positional relationship of each part at the time of installing a back surface reflection X-ray analyzer away from a sample.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
Here, a case where an imaging plate is used as an X-ray detector will be described.

<Back reflection X-ray analyzer>
(Configuration of back reflection X-ray analyzer)
FIG. 1 is a perspective view showing an example of the configuration of a back reflection X-ray analyzer to which the present invention can be applied. The illustrated back reflection X-ray analysis apparatus includes an X-ray tube 1 as an example of an X-ray emission unit and an imaging plate 2 as an example of an X-ray detector. The X-ray tube 1 emits X-rays toward a sample 3 that is a measurement object. Here, as an example of the sample 3, a plate (metal plate or the like) having a flat surface (upper surface) is assumed.

The imaging plate 2 is used when measuring a two-dimensional intensity distribution of X-rays.
Specifically, the imaging plate 2 receives the diffracted X-rays diffracted on the surface of the sample 3 when the X-rays emitted from the X-ray tube 1 are incident on the sample 3, whereby the diffracted X-rays are received. It is possible to detect a diffraction ring (annular diffraction image) formed by. The imaging plate 2 is formed, for example, by coating a phosphorescent phosphor powder on one side of an organic film into a plate shape. For this reason, after the imaging plate 2 is exposed to X-rays, when the exposed portion is irradiated with laser light, light emission corresponding to the X-ray exposure amount is obtained. Therefore, an X-ray image reflecting the X-ray exposure amount can be obtained by measuring the light emission amount when the exposed portion of the imaging plate 2 after X-ray exposure is irradiated with laser light.

  The imaging plate 2 is formed in a disk shape as a whole. The imaging plate 2 is supported using, for example, a support member (not shown) having the same shape as the imaging plate 2. An X-ray passage hole 5 is formed at the center of the imaging plate 2. The X-ray passage hole 5 is a hole through which X-rays emitted from the X-ray tube 1 pass. The X-ray passage hole 5 is a circular hole that penetrates the imaging plate 2 in the thickness direction. One side of the imaging plate 2 is an X-ray light receiving unit 6. The X-ray light receiving unit 6 is a part that receives diffracted X-rays diffracted on the surface of the sample 3 when X-rays are incident on the sample 3 from the X-ray tube 1 through the X-ray passage hole 5 of the imaging plate 2. The X-ray light receiving unit 6 is constituted by one surface of the imaging plate 2 on the side opposite to the side where the X-ray tube 1 is disposed, and the surface coated with the above-described photostimulable phosphor powder. .

(Operation of back reflection X-ray analyzer)
In the back reflection X-ray analyzer configured as described above, X-rays emitted from the X-ray tube 1 enter the surface of the sample 3 through the X-ray passage hole 5 of the imaging plate 2. The figure shows an example of measuring the residual stress by analyzing the shape of the diffraction ring. X-rays on the surface of the sample 3 so that the X-rays emitted from the X-ray tube 1 enter the sample 3 from an oblique direction. Is set to be less than 90 degrees (for example, about 30 degrees). The imaging plate 2 is disposed obliquely with respect to the surface of the sample 3 in accordance with the incident angle of the X-ray, and the X-ray optical axis of the X-ray emitted from the X-ray tube 1. It is arranged in the direction orthogonal to.

  As described above, when X-rays are incident on the surface of the sample 3, the X-rays are diffracted there. The diffracted X-ray diffracted on the surface of the sample 3 is received by the X-ray light receiving unit 6 of the imaging plate 2. Thereby, the X-ray light-receiving part 6 is exposed by X-rays. At this time, an annular diffraction image is formed as a latent image on the X-ray light receiving unit 6 by exposure with X-rays. Thereafter, when a predetermined exposure time has elapsed, the emission of X-rays from the X-ray tube 1 is stopped. Next, the latent image accumulated so far in the X-ray light receiving unit 6 is read by a laser reader or the like. Thereby, the diffraction ring formed on the imaging plate 2 can be detected.

<First Embodiment>
FIG. 2 is a perspective view showing a schematic configuration of the back reflection X-ray analysis apparatus according to the first embodiment of the present invention, and FIG. 3 is a back reflection X-ray analysis apparatus according to the first embodiment of the present invention. It is a figure explaining the structure of the principal part. 3 is a view of FIG. 2 viewed from the front direction F. FIG. In FIG. 3, the surface of the sample 3 to be measured is a surface inclined from a plane perpendicular to the paper surface. For this reason, X-rays enter the sample 3 from the oblique direction as described above.

  The back reflection X-ray analyzer according to the first embodiment of the present invention selects any one of at least two specified distances when setting the camera length to be applied to X-ray analysis. The camera length variable setting means can be set. In this case, the camera length can be expressed by the distance from the X-ray passage hole 5 of the imaging plate 2 to the laser irradiation position O of the sample 3 in the optical axis direction of the X-ray emitted from the X-ray tube 1. The laser irradiation position O refers to a position at which the surface of the sample 3 to be measured is irradiated with a visible laser emitted from a laser emitting unit 11 described later. This will be described in detail below.

  The camera length variable setting means is configured by using a distance sensor mechanism 10 of a triangulation system. The distance sensor mechanism 10 includes a laser emitting unit 11, a prism 12 serving as an optical path changing unit, a prism moving mechanism 13, a slit 14, and a PSD (Position Sensitive Detector) 15 serving as a laser light receiving unit.

  The laser emitting unit 11 emits a visible laser (laser beam) to be irradiated on the sample 3. The prism 12 converts the optical path of the visible laser emitted from the laser emitting unit 11. The prism 12 is configured using, for example, a right-angle prism. The prism 12 is disposed so as to advance on the optical path of the X-ray emitted from the X-ray tube 1 as necessary. The prism 12 arranged on the X-ray optical path changes the traveling direction of the visible laser emitted from the laser emitting unit 11 by 90 degrees so that the optical axis of the visible laser becomes coaxial with the optical axis of the X-ray. , Transform the optical path of the visible laser.

  The prism moving mechanism 13 constitutes an advancing / retreating support unit that supports the prism 12 so as to be able to advance and retract with respect to the optical path of the X-ray emitted from the X-ray tube 1. The prism moving mechanism 13 moves the prism 12 back and forth with respect to the X-ray optical path by reciprocating the prism 12 in a direction orthogonal to the X-ray optical path (optical axis) from the X-ray tube 1 to the imaging plate 2. Let Accordingly, the prism 12 can be selectively (alternatively) arranged at a position where the prism 12 has advanced on the X-ray optical path from the X-ray tube 1 to the imaging plate 2 and a position where the prism 12 has been retracted from the optical path.

  The slit 14 has a slit hole 14 a and is disposed in front of the PSD 15. The slit 14 restricts the passage of the visible laser reflected by the sample 3 and directed to the PSD 15 when the visible laser emitted from the laser emitting unit 11 is irradiated to the sample 3 via the prism 12 by the slit hole 14a. Is. A converging lens (not shown) is attached to the slit hole 14a of the slit 14, and a visible laser beam converged by the converging lens is focused on the light receiving surface 15a of the PSD 15.

  The PSD 15 receives the visible laser beam reflected by the sample 3 at the light receiving surface 15a and can detect the light receiving position. The light receiving surface 15 a of the PSD 15 is arranged in parallel with the imaging plate 2 and the slit 14. The light receiving position of the visible laser on the light receiving surface 15a is a position where the visible laser focused by the above-described focusing lens is imaged. Here, as an example, there is an origin on one end side of the light receiving surface 15a of the PSD 15, and with this origin as a reference (zero), the light receiving position of the visible laser is a distance from the origin (hereinafter referred to as “PSD detection distance”). The detection mechanism is based on d. In this mechanism, the PSD detection distance d becomes longer as the camera length CL described above becomes shorter. On the contrary, the PSD detection distance d becomes shorter as the camera length CL becomes longer. For this reason, if the PSD detection distance d is known, the camera length CL can be obtained based on this.

  In the back reflection X-ray analysis apparatus having the above configuration, the camera length is set before X-rays are emitted from the X-ray tube 1 and X-ray analysis is performed. The camera length is set without emitting X-rays from the X-ray tube 1. To set the camera length, first, the prism 12 is advanced on the optical path of the X-ray by the prism moving mechanism 13. Next, a visible laser is emitted from the laser emitting unit 11 toward the prism 12. Then, the optical path of the visible laser is bent at a right angle by the prism 12. As a result, the optical axis of the visible laser is coaxial with the optical axis of the X-ray. For this reason, the visible laser is irradiated to the sample 3 through the X-ray passage hole 5 of the imaging plate 2. At this time, if the distance from the X-ray passage hole 5 of the imaging plate 2 to the laser irradiation position O of the sample 3 is within a presumable settable range of the camera length, the visible light reflected at the laser irradiation position O of the sample 3 is visible. The laser reaches the light receiving surface 15 a of the PSD 15 through the slit hole 14 a of the slit 14. Thereby, PSD15 detects camera length CL based on PSD detection distance d. This will be described in detail below.

Now, the meaning of each symbol shown in FIGS. 3 and 4 is defined as follows. FIG. 4 shows the positional relationship of each part when the back reflection X-ray analysis apparatus is installed close to the sample and when it is installed away from the sample.
Reference symbol B indicates the distance from the optical axis of the visible laser to the center position of the slit hole 14a of the slit 14 in the direction perpendicular to the optical axis of the visible laser from the prism 12 toward the X-ray passage hole 5 of the imaging plate 2. . The center position of the slit hole 14a is the origin of the PSD 15.
Reference symbol C indicates the distance from the center of the X-ray passage hole 5 of the imaging plate 2 to the slit surface of the slit 14.
Reference signs L (L ₁ , L ₂ ) denote the slit surface of the slit 14 and the sample 3 in the direction parallel to the optical axis of the X-ray from the X-ray tube 1 through the X-ray passage hole 5 of the imaging plate 2 toward the sample 3. This indicates the distance between the laser irradiation position O (O ₁ , O ₂ ) on the surface, L ₁ indicates the distance when the back reflection X-ray analyzer is installed close to the sample, and L ₂ indicates The distance when a back reflection X-ray analyzer is installed away from the sample is shown.
A symbol O (O ₁ , O ₂ ) indicates a measurement position (a position where X-rays are incident) on the surface of the sample 3, and O ₁ is a case where the back reflection X-ray analyzer is placed close to the sample. , And O ₂ indicates the measurement position when the back reflection X-ray analyzer is installed away from the sample.
Reference sign S indicates the center position of the slit hole 14a of the slit 14 (the optical center position of the lens when a lens is present).
Reference numeral f denotes between the center of the slit hole 14a of the slit 14 and the light receiving surface 15a of the PSD 15 in a direction parallel to the optical axis of the visible laser from the prism 12 through the X-ray passage hole 5 of the imaging plate 2 toward the sample 3. Indicates distance.
Among these, the distances indicated by the symbols B, C, and f are known information because they are determined by the mechanical configuration (mechanism design, etc.) of the back reflection X-ray analyzer. On the other hand, the distance indicated by the symbol L (L ₁ , L ₂ ) is unknown information because it varies depending on how close the back reflection X-ray analyzer is installed to the sample 3.

By the way, when the PSD detection distance d is measured in the PSD 15, the camera length CL can be detected by performing calculation using the PSD detection distance d by the control circuit of the distance sensor mechanism 10. For example, when illuminated with visible laser to the surface of the sample 3 through the prism 12 from the laser emitting section 11, if the PSD15 has received a visible laser at a position of the PSD sensing distance d _1, the following equation (1) it is possible to detect the camera length CL ₁ by.
CL ₁ = L ₁ + C = B · f / d ₁ + C (1)

Further, when the visible laser is received at the position of the PSD detection distance d ₂ when the visible light is irradiated from the laser emitting unit 11 to the surface of the sample 3 via the prism 12, the following equation (2) it is possible to detect the camera length CL ₂ by.
CL ₂ = L ₂ + C = B · f / d ₂ + C (2)

  Here, in the X-ray analysis using the back reflection X-ray analyzer, it is desirable to install the X-ray analyzer as close to the sample 3 as possible. There are two main reasons. The first reason is that, when the camera length is set shorter, X-rays with higher intensity are incident on the X-ray light receiving unit 6 of the imaging plate 2, thereby reducing the X-ray exposure time. The second reason is that when the imaging plates 2 of the same size are compared, X-rays having a larger diffraction angle can be received by the imaging plate 2 when the camera length is set shorter.

  However, if a convex portion exists on a part of the surface of the sample 3, when the back reflection X-ray analyzer is brought close to the sample 3 in an attempt to set the camera length short, for example, a part of the housing of the apparatus is In some cases, the projection 3 may interfere with the convex portion of the sample 3. Even in such a case, in the back reflection X-ray analysis apparatus according to the first embodiment of the present invention, the camera length applied to the X-ray analysis can be set without any problem. Specifically, the back reflection X-ray analyzer is installed away from the sample 3 so as not to interfere with the convex portion of the sample 3. Then, the camera length CL is detected under this installation state, and the camera length applied to the X-ray analysis is set to CL based on the detection result.

  When the setting of the camera length is thus completed, the prism 12 is retracted from the X-ray optical path by the prism moving mechanism 13. Thereafter, while maintaining the relative positional relationship between the back reflection X-ray analyzer and the sample 3 as it is, X-ray analysis of the sample 3 is performed by applying the previously set camera length.

(Effects of the first embodiment)
In the back reflection X-ray analysis apparatus according to the first embodiment of the present invention, the camera length is not fixed as in the prior art, and one of a plurality of specified distances can be selected and set as the camera length. it can. For this reason, for example, even when a convex portion exists on a part of the surface of the sample 3, it is possible to select and set a camera length at which the back reflection X-ray analyzer does not interfere with the convex portion. Therefore, it is possible to perform an X-ray analysis of the sample 3 by selecting an appropriate camera length corresponding to the measurement environment of the X-ray analysis. Further, when the camera length CL is changed, the PDS detection distance d is changed accordingly. For this reason, the camera length CL can be detected based on the PSD detection distance d. Therefore, it is possible to arbitrarily select and set the camera length during X-ray analysis within the range of the maximum value and the minimum value of the camera length CL.

  In the first embodiment of the present invention, the optical axis when the sample 3 is irradiated with the visible laser emitted from the laser emitting unit 11 and the X-ray emitted from the X-ray tube 1 are applied to the sample 3. The optical axis when irradiated is set to be coaxial. For this reason, on the surface of the sample 3, the irradiation position of the visible laser at the time of setting the camera length and the irradiation position of the X-ray at the time of X-ray analysis are always the same position. Therefore, the spot position of the visible laser irradiated to the sample 3 when the camera length is set becomes the X-ray irradiation position as it is during the X-ray analysis. Therefore, a visible laser can be effectively used as an index indicating the measurement position of the sample 3 to be subjected to X-ray analysis.

  As an application example of the first embodiment of the present invention, the entire X-ray analysis system including the X-ray tube 1, the imaging plate 2, and the above-described distance sensor mechanism 10 is used for the incident X-ray light. You may employ | adopt the structure which provided the analysis system moving mechanism (not shown) moved to an axial direction. When this configuration is adopted, by moving the entire mechanism of the X-ray analysis system by the analysis system moving mechanism with the measurement position of the sample 3 to be subjected to X-ray analysis fixed (uniquely determined), An arbitrary camera length can be set with the measurement position kept constant. In other words, even if the camera length is adjusted, it is not necessary to reset the measurement position, so that the adjustment becomes simple.

<Second Embodiment>
FIG. 5 is a diagram for explaining the configuration of the main part of a back reflection X-ray analyzer according to the second embodiment of the present invention. 5 is also a view of FIG. 2 viewed from the front direction F, and the measurement surface of the sample 3 is inclined from the plane perpendicular to the paper surface, and the X-rays are from the oblique direction as described above. Is incident.

  In the back reflection X-ray analysis apparatus according to the second embodiment of the present invention, the camera length variable setting means uses the triangulation distance sensor mechanism 10 as compared with the case of the first embodiment. Although the points are configured in common, the configuration of the distance sensor mechanism 10 is different.

  The distance sensor mechanism 10 includes a laser emitting unit 11, a slit 14, and a PSD 15. The distance sensor mechanism 10 is provided so as to be movable by the sensor moving mechanism 16. The basic configuration of the laser emitting unit 11, the slit 14, and the PSD 15 is the same as that of the first embodiment, but the arrangement of each is different as follows.

  The laser emitting unit 11 is disposed so as to face the sample 3 at an angle different from that of the X-ray tube 1 and the imaging plate 2. The visible laser emitted from the laser emitting unit 11 is configured to be directly irradiated onto the sample 3 through the outside of the imaging plate 2 so as not to interfere with the imaging plate 2. Further, the optical axis of the visible laser emitted from the laser emitting unit 11 and the optical axis of the X-ray emitted from the X-ray tube 1 are set so as to intersect each other.

  The slit 14 and the light receiving surface 15a of the PSD 15 are arranged outside the imaging plate 2 in parallel with each other. The sensor moving mechanism 16 moves the distance sensor mechanism 10 including the laser emitting unit 11, the slit 14, and the PSD 15 linearly and integrally in a direction parallel to the light receiving surface 15a of the PSD 15. For this reason, when the distance sensor mechanism 10 is moved by the sensor moving mechanism 16, the laser emitting unit 11, the slit 14, and the PSD 15 approach or separate from the imaging plate 2 accordingly.

The sensor moving mechanism 16 can employ, for example, the following configuration.
That is, although not shown, the laser emitting portion 11, the slit 14, and the PSD 15 constituting the distance sensor mechanism 10 are supported using a common base member. Further, the base member is supported so as to be linearly movable by using a guide member such as a guide rail or a guide shaft. As a drive system for movement, a motor or the like is used as a drive source, and a ball screw mechanism is used to convert rotational motion into linear motion and move the base member.

  In the back reflection X-ray analysis apparatus having the above configuration, when setting the camera length, a visible laser is emitted from the laser emitting unit 11 toward the sample 3. At this time, if the distance from the X-ray passage hole 5 of the imaging plate 2 to the laser irradiation position O of the sample 3 is within the settable range of the camera length assumed in advance, the visible laser reflected by the sample 3 is slit 14. The light receiving surface 15a of the PSD 15 through the slit hole 14a. Thereby, PSD15 detects camera length CL based on PSD detection distance d. This will be described in detail below.

Now, the meaning of each symbol shown in FIGS. 5, 6 and 7 is defined as follows. 6 shows the positional relationship of each part when the back reflection X-ray analyzer is installed close to the sample, and FIG. 7 shows the positional relation of each part when installed far away.
Reference symbol B indicates the distance from the optical axis of the visible laser to the center position of the slit hole 14 a of the slit 14 in the direction orthogonal to the optical axis of the visible laser from the laser emitting portion 11 toward the sample 3. The center position of the slit hole 14a is the origin of the PSD 15.
Reference symbol C indicates the distance from the center of the X-ray passage hole 5 of the imaging plate 2 to the slit surface of the slit 14.
Reference numerals L (L ₁ , L ₂ ) denote laser irradiation positions O (O ₁ , O ₁ , O ₂ ) on the slit surface of the slit 14 and the surface of the sample 3 in a direction parallel to the optical axis of the visible laser from the laser emitting unit 11 toward the sample 3. O ₂ ), L ₁ indicates the distance when the back reflection X-ray analyzer is set close to the sample, and L ₂ indicates that the back reflection X-ray analyzer is away from the sample. Indicates the distance when set.
A symbol O (O ₁ , O ₂ ) indicates a measurement position (a position where X-rays are incident) on the surface of the sample 3, and O ₁ is a case where the back reflection X-ray analyzer is placed close to the sample. , And O ₂ indicates the measurement position when the back reflection X-ray analyzer is installed away from the sample.
Reference sign S indicates the center position of the slit hole 14a of the slit 14 (the optical center position of the lens when a lens is present).
The symbol f indicates the distance between the center of the slit hole 14a of the slit 14 and the light receiving surface 15a of the PSD 15 in the direction parallel to the optical axis of the visible laser from the laser emitting portion 11 toward the sample 3.
A symbol α indicates an angle formed by the optical axis of the X-ray from the X-ray tube 1 through the X-ray passage hole 5 of the imaging plate 2 toward the sample 3 and the optical axis of the visible laser from the laser emitting unit 11 toward the sample 3. .
Of these, the distances indicated by the symbols B, C, and f and the angle indicated by the symbol α are known information because they are determined by the mechanical configuration of the back reflection X-ray analyzer. On the other hand, the distance indicated by the symbol L (L ₁ , L ₂ ) is unknown information because it varies depending on how close the back reflection X-ray analyzer is installed to the sample 3.

Therefore, when the PSD detection distance d is measured in the PSD 15, the camera length CL can be detected by performing calculation using the PSD detection distance d by the control circuit of the distance sensor mechanism 10. For example, when irradiated with visible laser from the laser emitting section 11 on the surface of the sample 3, when the PSD15 has received a visible laser at a position of the PSD sensing distance d _1, the camera length CL ₁ by the following equation (3) Can be detected.
CL ₁ = (L ₁ + C) / cos α = (B · f / d ₁ + C) / cos α (3)

In addition, when the visible light is irradiated at the position of the PSD detection distance d ₂ when the visible laser is irradiated from the laser emitting unit 11 to the surface of the sample 3, the camera length CL ₂ is calculated by the following equation (4). Can be detected.
CL ₂ = (L ₂ + C) / cos α = (B · f / d ₂ + C) / cos α (4)

Here, in the second embodiment, the optical axis of the X-ray emitted from the X-ray tube 1 toward the sample 3 and the optical axis of the visible laser emitted from the laser emitting unit 11 toward the sample 3. It is necessary to set the position at which the crossing and the measurement position of the sample 3 are. For this reason, when the camera length setting at the time of X-ray analysis is changed from the camera length CL ₁ to the camera length CL ₂ , it is necessary to move the laser emitting unit 11, the slit 14, and the PSD 15 by the sensor moving mechanism 16. The amount of movement at that time is (CL ₁ -CL ₂ ) sin α. Further, it is necessary to visually adjust the measurement position of the sample 3 separately. Specifically, the sample position is adjusted so that the visible laser beam hits the measurement position.

The amount of movement of the distance sensor mechanism 10 by the sensor moving mechanism 16 may be controlled by the following method, for example.
First, when the distance sensor mechanism 10 is linearly moved by the sensor moving mechanism 16, the intersection of the X-ray and the visible laser emitted from the laser emitting unit 11 in the optical axis direction of the X-ray emitted from the X-ray tube 1. The position to perform is displaced. Specifically, when the distance sensor mechanism 10 is linearly moved in the direction approaching the imaging plate 2 by the sensor moving mechanism 16, the position at which the X-ray and the visible laser intersect with each other is on the imaging plate 2 on the optical axis of the X-ray. Displaces in the direction approaching. In addition, when the distance sensor mechanism 10 is linearly moved away from the imaging plate 2 by the sensor moving mechanism 16, the position where the X-ray and the visible laser intersect with each other moves away from the imaging plate 2 on the optical axis of the X-ray. It is displaced to.

Thereby, the camera length at the time of X-ray analysis can be arbitrarily selected and set. For this reason, even when a convex portion exists on a part of the surface of the sample 3, it is possible to select and set a camera length at which the back reflection X-ray analyzer does not interfere with the convex portion. Therefore, it is possible to perform an X-ray analysis of the sample 3 by selecting an appropriate camera length corresponding to the measurement environment of the X-ray analysis.
Note that the moving direction of the distance sensor mechanism 10 by the sensor moving mechanism 16 does not necessarily have to be a direction parallel to the light receiving surface 15a of the PSD 15, and any direction other than the direction S-O in the figure. It doesn't matter.

<Third Embodiment>
FIG. 8 is a diagram illustrating the configuration of the main part of a back reflection X-ray analyzer according to the third embodiment of the present invention. 8 is also a view of FIG. 2 viewed from the front direction F, and the measurement surface of the sample 3 is inclined from the plane perpendicular to the paper surface, and the X-ray is from the oblique direction as described above. Is incident.

  In the back reflection X-ray analysis apparatus according to the third embodiment of the present invention, the configuration of the sensor moving mechanism 16 is different from that in the second embodiment. That is, in the second embodiment, the sensor moving mechanism 16 is configured to linearly move the distance sensor mechanism 10. However, in the third embodiment, the sensor moving mechanism 16 is configured to move the distance sensor mechanism 10. Is configured to rotate. This will be described in detail below.

  The laser emitting unit 11 is disposed so as to face the sample 3 at an angle different from that of the X-ray tube 1 and the imaging plate 2. The visible laser emitted from the laser emitting unit 11 is configured to be directly irradiated onto the sample 3 through the outside of the imaging plate 2 so as not to interfere with the imaging plate 2. Further, the optical axis of the visible laser emitted from the laser emitting unit 11 and the optical axis of the X-ray emitted from the X-ray tube 1 are set so as to intersect each other. This point is the same as in the second embodiment.

  The sensor moving mechanism 16 integrally rotates the distance sensor mechanism 10 (laser emitting unit 11, slit 14, PSD 15) with the center of the slit hole 14a of the slit 14 as the rotation center. When the distance sensor mechanism 10 is actually rotationally moved by the sensor moving mechanism 16, the position where the X-ray and the visible laser intersect is displaced accordingly. Specifically, as shown in FIG. 9, when the distance sensor mechanism 10 is rotated clockwise by the sensor moving mechanism 16, the laser emitting unit 11, the PSD 15 and the like are displaced from the solid line to the position indicated by the broken line. Accordingly, the position where the X-ray and the visible laser intersect with each other is displaced in the direction away from the imaging plate 2 on the optical axis of the X-ray. In addition, when the distance sensor mechanism 10 is rotated counterclockwise by the sensor moving mechanism 16 from that state, the laser emitting unit 11, the PSD 15 and the like are displaced from the broken line to the position indicated by the solid line, and X-rays and visible rays are accordingly displayed. The position where the laser intersects is displaced in a direction approaching the imaging plate 2 on the optical axis of the X-ray.

The sensor moving mechanism 16 can employ, for example, the following configuration.
That is, although not shown, the laser emitting portion 11, the slit 14, and the PSD 15 constituting the distance sensor mechanism 10 are supported using a common base member. Moreover, this base member is rotatably supported using a pivot. As a drive system for movement, a motor or the like is used as a drive source, the drive force is transmitted to the base member by a gear mechanism, and the base member is rotated.

  In the back reflection X-ray analysis apparatus having the above configuration, when setting the camera length, a visible laser is emitted from the laser emitting unit 11 toward the sample 3. At this time, if the distance from the center Cc of the X-ray passage hole 5 in the X-ray receiving part 6 of the imaging plate 2 to the laser irradiation position O of the sample 3 is within a presumable settable range of the camera length, the sample 3 The visible laser reflected by the laser beam reaches the light receiving surface 15a of the PSD 15 through the slit hole 14a of the slit 14. Thereby, PSD15 detects camera length CL based on PSD detection distance d. This will be described in detail below.

Now, as shown in FIG. 9, it is assumed that the distance sensor mechanism 10 is rotated clockwise by the angle β by the sensor moving mechanism 16. In such a case, the arrangement state of each part of the distance sensor mechanism 10 changes from the state shown in FIG. 10 to the state shown in FIG. At this time, a two-dimensional coordinate is assumed with the center position S of the slit hole 14a of the slit 14 serving as the rotation center of the distance sensor mechanism 10 in the state before rotational movement. Specifically, in FIG. 10, an SXY coordinate system is assumed in which an axis parallel to the optical axis of the visible laser from the laser emitting portion 11 toward the sample 3 is defined as the Y axis, and an axis orthogonal thereto is defined as the X axis. In such a case, before the distance sensor mechanism 10 is rotated, the intersection of the optical axis of the X-ray and the optical axis of the visible laser is O ₁ , and the angle formed by them is α _1. After the rotational movement by the angle β, it becomes as shown in FIG. That is, at the intersection the O ₂ in the optical axis of the visible laser X-ray, their angle α2 becomes, alpha ₂ is the alpha _1-beta. Further, by β rotation about the center position S of the slit hole 14a of the slit 14, the SXY coordinate system becomes the SX'Y 'coordinate system, and the intersection of the X-ray and the visible laser is on the optical axis of the X-ray. It is displaced in a direction away from the imaging plate 2. In the measurement of the X-ray analysis, the measurement position of the sample 3 is set at the intersection of the X-ray and the visible laser. For this reason, before and after rotating the distance sensor mechanism 10 in the clockwise direction as described above, the camera length changes from a short distance to a long distance.

Here, when the distance sensor mechanism 10 is rotated by an angle β as described above, the measurement position of the surface of the sample 3 is aligned with the intersection O ₂ between the X-ray and the visible laser. Further, the coordinates of the center Cc of the X-ray passage hole 5 in the X-ray light receiving unit 6 of the imaging plate 2 are set to (X _CC , Y _CC ) in the SXY coordinate system, and Cc in the SX′Y ′ coordinate system after the rotational movement is set. Let the coordinates be (X ′ _CC , Y ′ _CC ). A camera length CL ₁ in FIG. 10, camera length CL ₂ of FIG. 11 after β rotation, each of the following equation (5) is determined from the equation (6).

CL ₁ = (L ₁ + Y _CC ) / cos α ₁ = (B · f / d ₁ + C) / cos α ₁ (5)
CL ₂ = (L ₂ + Y ′ _CC ) / cos α ₂ = [B · f / d ₂ + {(L ₁ + C) tan α ₁ + B} sin β + C cos β] / cos (α ₁ -β) (6 )

In the above formulas and FIGS. 8 to 11, the meanings of the respective symbols are as follows.
Reference symbol B indicates the distance from the optical axis of the visible laser to the center position of the slit hole 14 a of the slit 14 in the direction orthogonal to the optical axis of the visible laser from the laser emitting portion 11 toward the sample 3. The center position of the slit hole 14a is the origin of the PSD 15.
Symbol C indicates the distance from the center Cc of the X-ray passing hole 5 of the imaging plate 2 in the state of FIG. 10 the angle between the optical axis and the visible laser of X-ray is alpha ₁ to the slit surface of the slit 14.
Reference numerals L (L ₁ , L ₂ ) denote laser irradiation positions O (O ₁ , O ₁ , O ₂ ) on the slit surface of the slit 14 and the surface of the sample 3 in a direction parallel to the optical axis of the visible laser from the laser emitting unit 11 toward the sample 3. O ₂ ), L ₁ indicates the distance when the back reflection X-ray analyzer is set close to the sample, and L ₂ indicates that the back reflection X-ray analyzer is away from the sample. Indicates the distance when set.
A symbol O (O ₁ , O ₂ ) indicates a measurement position (a position where X-rays are incident) on the surface of the sample 3, and O ₁ is a case where the back reflection X-ray analyzer is placed close to the sample. , And O ₂ indicates the measurement position when the back reflection X-ray analyzer is installed away from the sample.
Reference sign S indicates the center position of the slit hole 14a of the slit 14 (the optical center position of the lens when a lens is present).
The symbol f indicates the distance between the center of the slit hole 14a of the slit 14 and the light receiving surface 15a of the PSD 15 in the direction parallel to the optical axis of the visible laser from the laser emitting portion 11 toward the sample 3.
Reference symbols α (α ₁ , α ₂ ) denote the X-ray optical axis from the X-ray tube 1 to the measurement position of the sample 3 through the X-ray passage hole 5 of the imaging plate 2, and the measurement position of the sample 3 from the laser emitting unit 11. Indicates the angle formed by the optical axis of the visible laser toward the surface, α ₁ indicates the angle when the back reflection X-ray analyzer is installed close to the sample, and α ₂ indicates the back reflection X-ray analyzer. Indicates the angle when placed away from the sample.
Among them, reference numerals B, C, and distance indicated f is the initial angle code alpha ₁ is shown, since determined by the mechanical structure of the rear reflective X-ray analysis apparatus, both the known information. On the other hand, the distance indicated by the symbol L (L ₁ , L ₂ ) is unknown information because it varies depending on how close the back reflection X-ray analyzer is installed to the sample 3.

The amount of movement of the distance sensor mechanism 10 by the sensor moving mechanism 16 may be controlled by the following method, for example.
First, when the distance sensor mechanism 10 is rotationally moved by the sensor moving mechanism 16, the intersection of the X-rays and the visible laser emitted from the laser emitting unit 11 in the optical axis direction of the X-rays emitted from the X-ray tube 1. The position to perform is displaced. Specifically, when the distance sensor mechanism 10 is rotated counterclockwise in the figure by the sensor moving mechanism 16, the position where the X-ray and the visible laser intersect with each other is placed on the imaging plate 2 on the optical axis of the X-ray. Displace in the approaching direction. Further, when the distance sensor mechanism 10 is rotated clockwise by the sensor moving mechanism 16, the position where the X-ray and the visible laser intersect is displaced in a direction away from the imaging plate 2 on the optical axis of the X-ray. To do.

Therefore, when the combined camera length at the time of X-ray analysis to CL _1, a movement control position when PSD15 to receiving a visible laser at a position of the PSD sensing distance d _1, the camera length at the time of X-ray analysis CL ₂ The movement control position when the PSD 15 receives the visible laser at the position of the PSD detection distance d ₂ is experimentally obtained in advance and stored in the control circuit (not shown) of the distance sensor mechanism 10. deep. When the camera length at the time of X-ray analysis is to be matched with the X-ray irradiation distance CL ₁ or CL ₂ , the sensor moving mechanism 16 is used to move the distance sensor mechanism 10 to the movement control position stored in the control circuit in advance. Controls the amount of movement.

Thereby, when setting the camera length at the time of X-ray analysis, it is possible to select one of the two prescribed distances such as CL ₁ and CL ₂ and set it as the camera length. For this reason, for example, even when a convex portion exists on a part of the surface of the sample 3, it is possible to select and set a camera length at which the back reflection X-ray analyzer does not interfere with the convex portion. Therefore, it is possible to perform an X-ray analysis of the sample 3 by selecting an appropriate camera length corresponding to the measurement environment of the X-ray analysis. Further, by storing the relationship between the movement control position and the X-ray irradiation distance in the control circuit in more detail, the camera length at the time of X-ray analysis can be arbitrarily selected and set.

(Modifications, etc.)
The technical scope of the present invention is not limited to the above-described embodiments, and includes various modifications and improvements as long as the specific effects obtained by the constituent elements of the invention and combinations thereof can be derived.

  For example, in each of the above embodiments, the example using the distance sensor mechanism of the triangulation method has been shown, but the present invention is not limited to this, and other examples such as a time-of-flight method and a phase difference distance measurement method are available. A type of distance sensor may be used. The time-of-flight method is a method of measuring the distance based on the time until the light emitted toward the measurement object is reflected by the measurement object and returns. The phase difference ranging method is a method of measuring a distance based on a phase shift that occurs until light returns from a measurement reflecting object when the light is emitted toward the measurement object.

  The camera length variable setting means may be any configuration that can select any one of at least two different specified distances and set it as the camera length. For this reason, for example, two distance sensor mechanisms are provided, and one distance sensor mechanism detects that the first specified distance corresponding to the first camera length is reached, and the other distance sensor mechanism detects the first distance. It may be configured to detect that the second specified distance corresponding to the camera length of 2 is reached.

  Further, the back reflection X-ray analysis apparatus according to the present invention can be applied to both a stationary type and a portable type, but is particularly useful when applied to a portable type back reflection X-ray analysis apparatus.

1 ... X-ray tube 2 ... Imaging plate (X-ray detector)
3 ... Sample (object to be measured)
DESCRIPTION OF SYMBOLS 10 ... Distance sensor mechanism 11 ... Laser emission part 12 ... Prism (optical path conversion means)
13. Prism moving mechanism (advance / retreat support means)
15 ... PSD (Laser receiver)
16 ... Sensor moving mechanism

Claims (9)

An X-ray emitting unit that emits X-rays toward the measurement object;
An annular diffraction formed by the diffracted X-ray by receiving the diffracted X-ray diffracted by the measurement object when the X-ray emitted from the X-ray emission part is incident on the measurement object. An X-ray detector capable of detecting an image;
When setting the camera length defined by the distance from the X-ray detector to the measurement object in the direction of the optical axis of the X-rays emitted from the X-ray emission part, the first camera length corresponding to the first camera length is set. One of a plurality of specified distances including a specified distance and a second specified distance corresponding to a second camera length different from the first camera length can be selected and set. Camera length variable setting means;
A back reflection X-ray analysis apparatus comprising: The back reflection X-ray analysis apparatus according to claim 1, wherein the camera length variable setting unit is configured using a triangulation distance sensor mechanism. The distance sensor mechanism is
A laser emitting section for emitting a visible laser to be irradiated to the measurement object;
A laser receiving unit that receives a visible laser beam emitted from the laser emitting unit and reflected by the measurement object;
The back reflection X-ray analysis according to claim 2, wherein the laser receiving position of the laser receiving unit is changed according to a distance from the X-ray detector to the measurement object. apparatus. An optical axis when the measurement object is irradiated with the visible laser emitted from the laser emitting unit, and an optical axis when the measurement object is irradiated with the X-ray emitted from the X-ray emitting unit Is set to be coaxial. The back reflection X-ray analysis apparatus according to claim 3, wherein: An optical path converting means for converting the optical path of the visible laser emitted from the laser emitting section so that the optical axis of the visible laser is coaxial with the X-ray emitted from the X-ray emitting section;
Advancing / retreating support means for supporting the optical path conversion means so as to be movable back and forth with respect to the optical path of the X-rays emitted from the X-ray emitting section;
The back reflection X-ray analysis apparatus according to claim 4, comprising: An optical axis when the measurement object is irradiated with the visible laser emitted from the laser emitting unit, and an optical axis when the measurement object is irradiated with the X-ray emitted from the X-ray emitting unit Are set so as to intersect with each other. The back reflection X-ray analysis apparatus according to claim 3, wherein: The back reflection X-ray analysis apparatus according to claim 6, further comprising a sensor moving mechanism that moves a position where the X-ray and the visible laser intersect by moving the distance sensor mechanism. The back reflection X-ray analysis apparatus according to claim 7, wherein the sensor moving mechanism moves the distance sensor mechanism linearly. The back reflection X-ray analysis apparatus according to claim 7, wherein the sensor moving mechanism rotates the distance sensor mechanism.

Images