JP3419133B2 - X-ray spectrometer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray spectrometer, and more particularly to a linear condensing X-ray spectrometer that moves a spectroscopic element along a straight line passing through an analysis point. About. 2. Description of the Related Art An X-ray spectroscope used in an apparatus such as an X-ray microanalyzer irradiates an analysis point on a sample with X-rays, and the X-rays emitted from the analysis point are separated by a spectroscopic element. Then, the light is incident on the detector and measurement is performed. As this X-ray spectrometer, a linear focusing X-ray spectrometer is known. In this linear focusing X-ray spectrometer, for example, as shown in FIG. 8, an analysis point on a sample, a spectroscopic element, and a detector are arranged on the same Rowland circle, and an incident angle θ of X-rays to the spectroscopic element
In order to perform X-ray spectroscopy while keeping the X-ray emission angle θ to the detector equal and the X-ray emission direction from the analysis point always kept constant, It moves along one straight line passing through the analysis point. At this time, the angle of incidence of X-rays incident on the spectral element is changed by rotating the spectral element itself. In a conventional linear focusing X-ray spectrometer,
In order to maintain the relationship between the analysis point and the spectroscopic element detector, for example, a link mechanism as shown in FIG. 9 guides the spectroscopic element to move along a straight line passing through the analysis point. In FIG. 9, X-rays emitted in the X-axis direction from an analysis point on the sample are separated by a spectroscopic element, and the separated X-rays are detected by a detector. At this time, the spectral element moves linearly along the X axis. A spectroscopic element that performs this linear movement, an analysis point on the sample, and a detector are arranged on the circumference of the same Rowland circle, and a second link that moves with a first link fixed to determine the angle of the detector Is constituted. The first link is an arc having a radius R of a Rowland circle centered on the analysis point on the sample, and is fixed to the X-ray spectrometer main body. On the other hand, the second link is a link having a length of R, one end of which moves along the first link, and the other end is provided with a spectral element. The distance from the analysis point on the sample to the spectroscopic element and the distance from the spectroscopic element to the detector are kept at the same distance by a link mechanism (not shown). FIG. 10 is a schematic diagram for explaining another conventional X-ray spectrometer. The X-ray spectrometer shown in FIG. 10 includes a first movement axis arranged along a first straight line (AA ′) passing through an analysis point on a sample, and a second movement axis passing through the analysis point on the sample.
A second moving axis arranged along a straight line (A-A "), and a light-splitting element arranged on a table moving on the first moving axis such that its lattice plane tangent is in contact with a Rowland circle; Second
A third straight line (DD ′) intersecting with the straight line (AA ′)
On a table that moves along the second movement axis,
A third axis rotatably installed at the intersection (D) of the second straight line and the third straight line, and a detector provided on a table sliding on the third axis are constituent elements. As a mechanism for connecting these components, a mechanism is provided between a central portion (B) of the spectral element that moves on the first movement axis and an intersection (D) between the second straight line and the third straight line. A first mechanism for linking the movements of the movable table on the first movable axis and the movable table on the second movable axis, so as to always keep the length of the optical element constant even when the spectroscopic element moves; The angle between the straight line and the second straight line is always the straight line connecting the central portion (B) of the spectral element and the intersection (D) and the second straight line (AA) even if the intersection (D) moves. ) And a third mechanism for always restricting the slit point of the detector on the Rowland circle. The first mechanism and the second mechanism determine the distance between the sample and the spectroscopic element and the distance between the spectroscopic element and the detector on the Rowland circle. [0008] However, in the conventional X-ray spectroscope, the sample and the stage for moving the sample constitute the X-ray spectrometer. For example, in the conventional X-ray spectrometer shown in Fig. 9, there is a problem that the link is an arc having a center at an analysis point on a sample and a radius R of a Roland circle. Therefore, the size of the sample and the sample stage and the moving range of the sample and the sample stage are limited by the fixed link to narrow the analysis range, and the movable range of the spectroscopic element is also limited. Further, in the conventional X-ray spectrometer shown in FIG. 10, the angle between the first moving axis and the second moving axis increases as the spectral range increases, and the second Therefore, the moving axis becomes longer in the direction of the sample, so that the size of the sample and the sample stage and the moving range thereof are restricted to narrow the analysis range, and the movable range of the spectroscopic element is also restricted. An object of the present invention is to solve the above-mentioned problems of the conventional X-ray spectrometer and to provide an X-ray spectrometer having a large movable range of a sample and a sample stage. According to the present invention, there is provided an X-ray spectroscope which disperses X-rays from an analysis point by a spectroscopic element which moves on a straight line passing through the analysis point and performs detection by a detector. A first link having an arc having a radius twice as large as a trajectory, a second link restrained by the first link, a distance from the origin to the spectral element, and a distance from the spectral element to the detector. To equidistant A second link having a trajectory along an arc having the radius of the Roland circle as the trajectory, the spectroscopic element being provided at one end of the link, and the detector being restrained on the trajectory of the arc. The above-mentioned object is achieved by causing a movement to cause a point on the arc trajectory to be constrained on the arc trajectory of the first link. FIG. 1 is a schematic configuration diagram for explaining an X-ray spectrometer of the present invention. In FIG. 1, a sample 11 is arranged at an analysis point 1, and X-rays emitted from the analysis point 1 are separated by a spectral element 2, and the spectral X-rays are detected by a detector 3. The X-ray spectrometer according to the present invention employs a link mechanism having a first link 6, a second link 7, and a third link (not shown), and the analysis point 1, the spectroscopic element 2, and the detector. 3 is arranged on the Rowland circle 4. Here, the first link 6 is an arc whose origin is the position of the analysis point 1 and whose center is the origin and whose radius is 2R which is twice as large as the radius of the Roland circle 4 is R. 5 is a locus, and is fixed to the X-ray spectrometer. The second link 7 is a link whose locus is an arc having the radius R of the Rowland circle 4 as a radius. The second link 7 is provided with the spectroscopic element 2 at one end thereof, and causes the detector 3 to move in a constrained manner on the locus of the arc of the second link. Note that FIG. 1 does not show a connecting member that connects the second link and the spectral element. Further, the second link 7 performs a constraining motion on the first link by moving a point on the arc trajectory constrained on the arc trajectory of the first link 6. A third link (not shown) is an ordinary link that restricts the distance from the position of the analysis point 1 which is the origin to the spectroscopic element 2 and the distance from the spectroscopic element 2 to the detector 3 to be equal. Thus, for example, it can be constituted by a wire mechanism. In an embodiment of the present invention, the trajectory of the arc of the first link and the trajectory of the arc of the second link are configured to overlap in the thickness direction of the link, whereby the second link is formed. To the first link,
The detector can be moved along the arc trajectory of the second link. Another embodiment of the present invention comprises a biasing means for biasing the second link in the first link direction, whereby the second link is separated from the first link by its own weight. This can prevent the second link from being restrained by the first link. Next, the operation of the X-ray spectrometer of the present invention will be described with reference to FIGS. Linear concentrating X according to the present invention
The X-ray spectroscope is a device that performs X-ray spectroscopy while moving the spectroscopic element along a straight line passing through the analysis point, and the spectroscopic element linearly moves along the X axis in the drawing. At the position of the spectroscopic element 2 shown in FIG. 1, the Rowland circle 4 (dot-dash line in the figure) on which the analysis point 1, the spectroscopic element 2 and the detector 3 are mounted on the circumference thereof is indicated by 41 in the figure. In the position shown, the second link 7 is in contact with the first link 6 at a point P1. Here, the distance between the analysis point 1 and the spectroscopic element 2 and the distance between the spectroscopic element 2 and the detector 3 are arranged equidistant by a third link (not shown). Thereby, the X-rays from the analysis point 1 are detected by the detector 3 after being separated by the spectroscopic element 2. Next, the spectroscopic element 2 is moved along the X axis,
It is moved from the position shown in FIG. 1 to the position shown in FIG. This movement moves the Rowland circle 4 to a position indicated by reference numeral 42 in FIG. 2, and causes the second link 7 supporting the spectroscopic element 2 at one end thereof to be restrained by the arc trajectory of the first link 6. While moving. At this time, the second link 7 contacts at the point P2 of the locus of the arc of the first link 6. The first link 6 moves while contacting the second link without slipping. Therefore, when the first link 6 moves on the trajectory of the first link 7, the contact point between the first link 6 and the first link 7 always has a one-to-one relationship.
Since this contact point P2 is a point on the arc of the second link 7 and a point on the arc of the first link 6,
The second link 7 overlaps on the Rowland circle 42 passing through the analysis point 1 and the spectral element 2. Therefore, detector 3
Are arranged on the same Rowland circle 42, and even if the spectroscopic element 2 moves on the X axis, the analysis point, the spectroscopic element and the detector are always located on the same Rowland circle. At this time, the distance from the analysis point 1 to the spectroscopic element 2 is restricted by the third link so as to be equal to the distance from the spectroscopic element 2 to the detector 3. Therefore, when the spectroscopic element moves on a straight line passing through the analysis point, the analysis point, the spectroscopic element, and the detector are always rolanded by the link mechanism of the first link, the second link, and the third link. X placed on the circle and the distance from the analysis point to the spectroscopic element and the distance from the spectroscopic element to the detector are equidistant, and X
The line can be detected by a detector after being separated by a spectroscopic element. According to this configuration, the distance between the analysis point and the first link fixed to the X-ray spectrometer is twice as long as the radius of the Roland circle. The distance can be made larger than in the case, and a margin can be provided in the distance between the link and the analysis point. Embodiments of the present invention will be described below in detail with reference to the drawings. (Structure of one embodiment of the present invention) A schematic structure diagram illustrating the structure of one embodiment of the present invention, illustrating an X-ray spectrometer of the present invention in FIG.
This will be described with reference to a perspective view illustrating the first link and the second link of the present invention in FIG. 4 and a schematic configuration diagram illustrating the third link of the present invention in FIG. FIG. 3 shows a first link and a second link of the present invention. The first link 6 is fixedly installed on the base 61 of the X-ray spectroscope. When the radius of the Roland circle is R, the first link is formed by an arc having a center at the analysis point 1 and a radius of 2R. Are formed. The analysis point 1 is a position on the sample 11 where the probe is irradiated and emits X-rays, and is a position fixed to the base 61 of the X-ray spectrometer. Also,
The sample 11 is movably mounted on a sample stage (not shown). The second link 7 is a link mechanism formed on the plate 71. The second link 7 moves while contacting the arc trajectory of the first link, and also moves the detector 3 along the arc trajectory. It is a mechanism to make it. The movement of the second link with respect to the first link is performed so that no slip occurs between the two links at the contact point. Therefore, there is a one-to-one correspondence between the contact points of both links. The second link 7 is formed by an arc having a radius of R, and includes an arc-shaped portion that comes into contact with the first link 6 and a groove portion that causes the detector 3 to move in a restricted manner along the arc. FIG. 4 shows the relationship between the first link and the second link. In FIG. 4, the first link 6 includes a convex portion 62 having an outer peripheral surface formed by an arc having a radius of 2R with the center being an analysis point (not shown), while the second link 7 includes:
A concave portion 72 having an arc having a radius R that comes into contact with the convex portion 62 and a groove 73 having an arc having the same radius R are provided. The first link 6 and the second link 7 have their convex portions 62 fitted into the concave portions 72, and for example, the second link 7 is moved to the first link by a biasing means such as a holding spring 74 shown in FIG.
Is urged toward the link 6 side.
In FIG. 3, both links are in contact at a contact point P. The detector 3 is mounted by inserting the shaft 31 into the groove 73. When the shaft 31 moves along the groove 73, the detector 3 moves while being restrained with respect to the second link. The slit 32 of the detector 3 is formed on the axis of the axis 31. In the second link 7, the trajectory point of the concave portion 72 in contact with the first link and the slit position of the detector 3 in the groove 73 are at the same position with respect to the plane of the base 61.
The link 7 is arranged so as to overlap in the thickness direction of the link 7 in the vertical direction. Therefore, the second link 7 can perform both the movement with respect to the first link and the restraining movement of the detector 3 without interfering with each other. The spectroscopic element 2 is provided on the plate 71 on the second link 7 side, and further movably supports a moving member 83 that moves linearly along a moving axis 82 and the detector 3. A driving shaft 81 is attached. FIG. 5 is a diagram for explaining the third link of the present invention. The third link 9 is a mechanism for restraining the distance from the analysis point 1 to the spectroscopic element 2 and the distance from the spectroscopic element 2 to the detector 3 to be equal, and is configured by a conventionally used wire mechanism. be able to. Therefore, only the outline of this wire mechanism will be described below. The wire mechanism is, for example, a first wire mechanism 91 provided on the spectral element from the detector along the moving axis 81.
(A two-dot chain line in FIG. 5) and a second wire mechanism 92 (a one-dot chain line in FIG. 5) that passes through the detector and the spectroscopic element and is provided along the movement axis 82. (Operation of One Embodiment of the Present Invention) Next, regarding the operation of one embodiment of the present invention, the relationship between the first link and the second link of the X-ray spectrometer of the present invention shown in FIG. 6 will be described. This will be described with reference to a perspective view of FIG. 7 and a schematic configuration diagram of the X-ray spectrometer of the present invention shown in FIG. FIG. 6A shows the positional relationship between the first link and the second link when the spectroscopic element 2 is located at a position near the analysis point. The second link 7 is biased toward the first link 6 by biasing means (not shown),
Contact is made at the contact point P, and the positional relationship is restricted.
Further, the detector 3 is provided with a groove on the second link 7,
And the distance from the spectroscopic element 2 is set by the third link, and the analysis point, the spectroscopic element 2 and the detector 3 are arranged on the Rowland circle 4. Next, the spectroscopic element 2 is connected to the moving shaft 8 shown in FIGS.
When the spectroscopic element 2 is moved away from the analysis point as shown in FIG. 6B, the second link 7 moves while changing the contact position by moving the spectroscopic element 2 as shown in FIG. I do. At this time, the second link 7 is urged toward the first link 6 by an urging means (not shown), and contacts at the contact point Q to restrict the positional relationship. The detector 3 is restrained by the groove on the second link 7 by the second link, and the distance from the spectroscopic element 2 is set by the third link (not shown).
Moves from the spectroscopic element by a distance away from the analysis point, and during and after the movement, the analysis point, the spectroscopic element 2 and the detector 3 are arranged on the Rowland circle 4. Similarly, even when the spectroscopic element 2 further linearly moves along the moving axis 82 in FIGS. 3 and 5, the analysis point and the spectroscopic element are moved by the first link, the second link, and the third link. The detector 2 and the detector 3 are always arranged on the Rowland circle 4, and the detector 3 can detect spectral X-rays separated by the spectral element. FIG. 6A shows a first link (fixed link) of the conventional X-ray spectrometer shown in FIG. 9 by a two-dot chain line. In the conventional X-ray spectrometer, since the fixed link is fixed at a distance of the radius R of the Roland circle from the analysis point, when the sample 11 or the sample table supporting the sample moves, interference occurs with the first link. Will wake up. For this reason, a large sample cannot be analyzed, and the moving range of the sample table is limited. On the other hand, in the X-ray spectrometer of the present invention,
The mechanism that limits the range of the sample or sample table is at a distance twice the radius of the Roland circle from the analysis point.
The sample can be moved to the position of the sample indicated by the two-dot chain line in the figure, and a large sample can be analyzed, and the moving range of the sample table can be expanded. (Modification) FIG. 11 is a schematic configuration diagram for explaining a modification of the present invention. In a modification of the present invention, the X-ray spectrometer having the same configuration as that of the above-described embodiment is installed by changing the arrangement angle, and the X-ray spectrometer shown in FIG.
Rotate so that the direction of the arrow in the figure is upward. In this arrangement, the incident electron beam is incident on the sample from the lateral direction, and detection is performed by a spectroscopic element and a detector arranged below. In this arrangement, the second link is located above the first link, and the second link always biases toward the first link by its own weight. Accordingly, the second link can be moved while being restrained by the first link without separately providing the urging means. (Effects of the Embodiment) According to the embodiment of the present invention, an X-ray spectrometer can be constituted by a link mechanism having a simple structure, and the movable range of the spectral element is enlarged to increase the spectral range. Can be expanded. In the X-ray spectrometer of the present invention, the second
By disposing the link above the first link, there is no need for urging means for urging the second link and the first link to restrain the first link and the second link. can do. As described above, according to the present invention,
An X-ray spectrometer having a large movable range of the sample and the sample stage can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram for explaining an X-ray spectrometer of the present invention. FIG. 2 is a schematic configuration diagram for explaining the X-ray spectrometer of the present invention. FIG. 3 is a schematic configuration diagram illustrating an embodiment of an X-ray spectrometer of the present invention. FIG. 4 is a perspective view illustrating a first link and a second link of the present invention. FIG. 5 is a schematic configuration diagram illustrating a second link of the present invention. FIG. 6 is a perspective view for explaining a relationship between a first link and a second link of the X-ray spectrometer of the present invention. FIG. 7 is a schematic configuration diagram of an X-ray spectrometer of the present invention. FIG. 8 is a diagram for explaining a relationship among an X-ray source, a spectral element, and a detector of the X-ray spectroscope. FIG. 9 is a schematic configuration diagram for explaining a conventional X-ray spectrometer. FIG. 10 is a schematic configuration diagram for explaining a conventional X-ray spectrometer. FIG. 11 is a schematic configuration diagram for explaining another embodiment of the X-ray spectrometer of the present invention. [Description of Signs] 1 ... X-ray source, 2 ... Spectroscopy element, 3 ... Detector, 4 ... Roland circle, 5 ... Circular arc, 6 ... First link, 7 ... Second link, 9 ... Third link , 11 ... sample.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-7-20069 (JP, A) JP-A-61-176840 (JP, A) JP-A-50-6678 (JP, U) 3320 (JP, B1) JP-B-43-24040 (JP, B1) JP-B-46-40520 (JP, B1) JP-B-44-14880 (JP, B1) (58) Fields surveyed (Int. ⁷ , DB name) G21K 1/06 G01N 23/22

Claims (1)

(57) [Claim 1] An X-ray spectrometer that disperses X-rays from an analysis point by a spectroscopic element that moves on a straight line passing through the analysis point, and detects the spectral X-rays with a detector. , A first link having a locus whose center is at an analysis point and having a radius twice as large as the radius of the Roland circle, and a link having a locus which has an arc having a radius of the Roland circle as the trajectory, At one end of the link, the detector is caused to perform a constrained movement on the locus of the arc, a point on the locus of the arc is a second link constrained on the locus of the arc of the first link, An X-ray spectrometer comprising: a third link that restricts a distance from the analysis point to the spectroscopic element and a distance from the spectroscopic element to the detector at equal distances.