JP3751008B2 - X-ray analyzer - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray analyzer that analyzes the structure and the like of a sample using X-rays.
[0002]
[Prior art]
An X-ray analyzer generally has an X-ray source that generates X-rays irradiated on a sample, and an X-ray detector that detects X-rays generated from the sample, such as diffraction X-rays and scattered X-rays. In this X-ray analyzer, in order to prevent the X-rays emitted from the X-ray source from directly entering the X-ray detector, that is, to prevent the direct beam from entering the X-ray detector. It is known to arrange a member for preventing the X-ray from traveling at a position, that is, a so-called direct beam stopper (see, for example, Patent Document 1).
[0003]
In addition, during the work of adjusting the mutual positional relationship of a plurality of elements constituting the X-ray optical system, so-called alignment work or setting work, strong X-rays enter the X-ray detector and damage the X-ray detector. In order to prevent this, it is also known to dispose a member that weakens the intensity of X-rays, for example, an X-ray absorption plate, in the X-ray optical system (see, for example, Patent Document 2).
[0004]
The direct beam stopper is disposed on the X-ray optical path during X-ray measurement. However, during the setting operation, the direct beam stopper may be retracted from the X-ray optical path. Further, the X-ray absorbing plate described above needs to be disposed on the X-ray optical path during the setting operation, but needs to be removed from the X-ray optical path during the X-ray measurement. Thus, elements such as a direct beam stopper and an X-ray absorbing plate need to be selected as necessary.
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 7-55727
[Patent Document 2]
JP-A-3-218449
[0006]
[Problems to be solved by the invention]
However, in the conventional X-ray analyzer, the position of the direct beam stopper and the position of the X-ray absorber are individually changed, and are not linked to each other. Therefore, in some cases, the direct beam or very strong X-ray enters the X-ray detector, and there is a risk of damaging the X-ray detector.
[0007]
The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an X-ray analyzer that can surely prevent very strong X-rays from entering an X-ray detector.
[0008]
[Means for Solving the Problems]
(1) In order to achieve the above object, an X-ray analysis apparatus according to the present invention includes an X-ray source that generates X-rays, an X-ray attenuation element that passes X-rays with reduced intensity, and the X-rays X-ray intensity adjusting means for selectively realizing a state where the attenuation element is placed on the X-ray optical path and a state where the attenuation element is not placed, a sample support means for holding the sample to be analyzed, and the progress of the direct beam emitted from the X-ray source A direct beam stopper for preventing the direct beam stopper, a stopper position adjusting means for moving the direct beam stopper between a position on the X-ray optical path and a retracted position for retracting from the position, and the direct beam stopper as viewed from the X-ray source. X-ray detection means arranged at a rear position; control means for moving the X-ray attenuation element and the direct beam stopper in conjunction with each other; An X-ray shutter that selects a state of emitting X-rays from the X-ray source and a state of shielding X-rays, and the control means includes the X-ray attenuation element and the direct beam stopper together When the X-ray shutter is not on the ray path, the X-ray shutter is interlocked so as to shield the X-ray. It is characterized by that.
[0009]
According to this X-ray analyzer, the X-ray attenuating element and the direct beam stopper can be moved in conjunction with each other. Therefore, when one is retracted to a position off the X-ray optical path, the other is automatically operated in conjunction with it. Can be placed on the X-ray optical path. As a result, the X-rays traveling along the X-ray optical path always strike either the X-ray attenuation element or the direct beam stopper. Therefore, even when an X-ray detector is disposed on the X-ray optical path, it is possible to reliably prevent the X-ray having strong intensity from entering the X-ray detector.
[0010]
(2) In the X-ray analyzer configured as described above, the control unit has a measurement mode which is a control mode for performing X-ray measurement. In this measurement mode, the control unit sets the direct beam stopper to X-ray light. The X-ray attenuating element can be placed at the retracted position in association with the road.
[0011]
In the measurement mode, the sample is irradiated with X-rays emitted from the X-ray source, and X-rays generated from the sample at that time, for example, scattered X-rays, are detected by the X-ray detector. At this time, if the direct beam stopper is placed on the X-ray optical path, the X-ray detector can be prevented from being damaged by the direct beam hitting the X-ray detector. At this time, the X-ray attenuating element automatically retracts to a position deviating from the X-ray optical path, so that the X-ray irradiated to the sample is not weakened.
[0012]
(3) In the X-ray analysis apparatus having the above configuration, the control means has a setting mode which is a control mode for setting the X-ray optical system, and in this setting mode, the control means controls the X-ray attenuation element. It can be placed on the X-ray optical path. In this case, it is desirable for the control means to ensure that the X-ray attenuation element is in the X-ray optical path regardless of the position of the direct beam stopper.
[0013]
Setting means that X-ray measurement can be normally performed by aligning a plurality of X-ray optical elements included in the X-ray analyzer, for example, slits, collimators, and the like at predetermined positions with respect to the X-ray optical path. It is work to make. This operation is sometimes called alignment.
[0014]
When performing this setting, if the X-ray attenuation elements are arranged on the X-ray optical path as described above, the X-ray optical elements can be aligned using the X-rays whose intensity has been reduced. Further, if the direct beam stopper is retracted to a position deviating from the X-ray optical path, it is possible to prevent the X-ray whose intensity has been weakened from being erroneously removed by the direct beam stopper.
[0015]
(4) In the X-ray analysis apparatus having the above-described configuration, the control unit has a setting mode which is a control mode for performing setting. In the setting mode, the control unit places the direct beam stopper at a retracted position, The X-ray attenuation element is placed on the X-ray optical path in conjunction with it, or the direct beam stopper is placed on the X-ray optical path, and the X-ray attenuation element is placed on the X-ray optical path in conjunction therewith. it can.
[0016]
In the setting mode, if the direct beam stopper is placed at the retracted position, and the X-ray attenuation element is controlled to be linked to the X-ray optical path in conjunction with the direct beam stopper, as described above, the X intensity attenuated by the X-ray attenuation element. Settings can be made using lines.
[0017]
In this setting mode, if the direct beam stopper is placed on the X-ray optical path and the X-ray attenuating element is placed on the X-ray optical path in conjunction with the direct beam stopper, that is, both are placed on the X-ray optical path. Whether or not the direct beam stopper itself is set at a normal position, that is, a setting relating to the direct beam stopper can be performed.
[0018]
(5) In the X-ray analysis apparatus having the above configuration, the control means has an X-ray monitor mode which is a control mode for checking whether or not X-rays are emitted, and in the X-ray monitor mode, the control means The direct beam stopper can be placed at the retracted position, and the X-ray attenuation element can be placed on the X-ray optical path in conjunction with the direct beam stopper.
[0019]
If the X-ray attenuation element is placed on the X-ray optical path, the intensity of the X-ray traveling along the X-ray optical path is reduced, and the direct beam stopper is retracted to a position outside the X-ray optical path, thereby reducing the intensity. Whether or not X-rays are emitted can be determined depending on whether or not the above-mentioned X-rays can be detected by an X-ray detector disposed on the X-ray optical path.
[0020]
(6) It is desirable that the X-ray analyzer configured as described above has an X-ray shutter that selects a state of emitting X-rays from the X-ray source and a state of shielding X-rays. In this case, it is desirable that the control means be interlocked so that the X-ray shutter shields X-rays when both the X-ray attenuation element and the direct beam stopper are not on the X-ray optical path. . In this way, in addition to the X-ray attenuation element and the direct beam stopper, if the opening / closing operation of the X-ray shutter is interlocked, excessive X-rays will accidentally enter the X-ray detector. This can be prevented more reliably.
[0021]
(7) The X-ray analyzer configured as described above is provided between the X-ray source and the direct beam stopper, and an X-ray optical system in which a sample is placed, and the direct as viewed from the X-ray source. X-ray detection means disposed behind the beam stopper. In that case, the X-ray optical system can be constituted by an optical system capable of detecting scattered X-rays generated from the sample in a small angle region centered on the X-ray optical path.
[0022]
The X-ray analyzer having this configuration is an X-ray analyzer generally called a small angle scattering device. This small-angle scattering apparatus is an X-ray generated in an angle region that cannot be measured by a wide-angle goniometer, that is, an angle region of about 0.08 ° to 4.5 ° from the center of the X-ray incident on the sample, for example, a so-called small-angle region. Measure scattered X-rays.
[0023]
In order to make it possible to recognize X-rays generated in such a small-angle region, in other words, in order to increase the resolution in the small-angle region, the small-angle scattering apparatus uses general X-ray diffraction with a wide-angle region as a measurement range. Structure different from the device, for example, (1) In order to prevent X-rays incident on the sample from being narrowed into a very narrow parallel beam and (2) to prevent unwanted parasitic scattered rays generated from the slit from entering the sample A large number of, for example, three slits are arranged in the long optical path length, (3) the X-ray passage from the X-ray source to the X-ray detector is kept in a vacuum state, or (4) the X from the sample Various configurations such as a very long length reaching the line detector, so-called camera length, and the like are employed.
[0024]
According to this small angle scattering apparatus, a difference in molecular structure in a substance having a long-period structure, such as an organic compound, which cannot be measured by a wide angle X-ray analyzer, can be grasped by a difference in X-ray diffraction pattern.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a case where the present invention is applied to a small angle scattering apparatus which is an example of an X-ray analyzer will be described as an example. In addition, this embodiment is an example of this invention and does not limit this invention.
[0026]
FIG. 1 shows a small angle scattering device 1 according to an embodiment of the present invention. This small angle scattering apparatus 1 includes an X-ray tube 6 having an X-ray source 4, a confocal mirror 7 as an X-ray condensing means for converging X-rays generated from the X-ray source 4 to one focus, 1 slit 8, second slit 9, third slit 11, sample support device 12, two-dimensional X-ray detector 13 as X-ray detection means, and zero-dimensional X-ray detector as X-ray detection means 15.
[0027]
The X-ray source 4 can be constituted by, for example, a filament (not shown) that generates heat when energized and a target (not shown) arranged to face the filament. A predetermined voltage, so-called tube voltage, is applied between the filament and the target. When a predetermined current is passed through the filament, the filament generates heat and emits thermoelectrons, and the thermoelectrons are accelerated by the tube voltage and collide with the surface of the target, and the wavelength corresponding to the material of the target from the collision area. X-rays are generated. The region where electrons collide on the surface of the target is the X-ray focal point.
[0028]
The X-ray tube 6 has a window (not shown) for emitting X-rays to the outside, and an X-ray shutter 57 is provided at the window. The X-ray shutter 57 has a shutter mechanism that can select an open state that allows the X-rays to travel from the X-ray source 4 and a closed state that blocks the X-rays from traveling. The controller 56 controls which state is selected by the shutter mechanism.
[0029]
The control device 56 can be configured by a single control circuit, or can be configured as a part of a control circuit that controls the entire small angle scattering device 1. Further, the control device 56 may be configured by a computer system including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a storage medium, or the like, or a computer It is also possible to use a sequence circuit that does not include
[0030]
An attenuator 41 as an X-ray intensity adjusting means is disposed between the second slit 9 and the third slit 11. A sample holder 42 can be attached to the sample support device 12, and the sample S to be measured is attached to the sample holder 42.
[0031]
In the case of this embodiment, the two-dimensional X-ray detector 13 is constituted by a detector plate using a stimulable phosphor. The detector plate 13 is a plate in which a stimulable phosphor is provided with a uniform thickness on the entire surface for detecting X-rays. The stimulable phosphor is a well-known substance, and can store a latent image having an energy corresponding to the intensity of the X-ray in the portion irradiated with the X-ray. For example, it is a substance having a function of emitting the accumulated energy latent image as light when irradiated with laser light.
[0032]
As the two-dimensional X-ray detector, a CCD X-ray detector formed by planarly arranging a plurality of CCDs (Charge Coupled Devices) other than the detector plate using the stimulable phosphor is used. You can also. The zero-dimensional X-ray detector 15 can be configured by a PC (Proportional Counter), an SC (Scintillation Counter), or the like.
[0033]
When small-angle scattering measurement is performed on the sample S, a detector plate 13 that is a two-dimensional X-ray detector is used as the X-ray detector. Further, when performing an operation of aligning the slits 8, 9, 11 and other elements at a predetermined position with respect to the X-ray optical path X0, that is, a setting operation, the zero-dimensional X-ray detector 15 is used as the X-ray detector.
[0034]
As shown in FIG. 4, the attenuator 41 is a circle that can rotate in the direction of arrow A or in the opposite direction about an axis 43 that extends parallel to the X-ray optical path X0 (that is, the direction perpendicular to the plane of FIG. 4). A plate 44 is provided. In this disk 44, five openings 46 are provided around the shaft 43 at equal angular intervals. Except for one opening 46a, four X-ray absorbing members 47a, 47b, 47c, and 47d having different X-ray absorption rates are attached to the four openings 46 as X-ray attenuation elements. Nothing is attached to the opening 46a and it is empty.
[0035]
The X-ray absorbing members 47a to 47d are made of a material capable of absorbing X-rays, for example, Cu (copper) or Al (aluminum), and have different thicknesses in order to make X-ray absorption rates different. For example, the X-ray absorbing member 47a is formed of Cu having a thickness of 0.3 mm, the X-ray absorbing member 47b is formed of Cu having a thickness of 0.2 mm, and the X-ray absorbing member 47c is formed of Cu having a thickness of 0.1 mm. The X-ray absorbing member 47d is formed of Al having a thickness of 0.2 mm.
[0036]
A rotation drive device 54 is connected to the shaft 43 of the disc 44. The rotation drive device 54 is configured using, for example, an electric motor capable of controlling the rotation angle. By rotating the disk 44 about the axis 43 by a predetermined angle by the rotation driving device 54, any one of the plurality of openings 46 can be selectively placed on the X-ray optical path X0. FIG. 4 shows a state in which the empty opening 46a is placed on the X-ray optical path X0. In this state, the X-ray absorbing member is not placed on the X-ray optical path, so that the X-ray source 4 in FIG. The emitted X-rays pass through the attenuator 41 without being attenuated.
[0037]
Various means for determining which one of the X-ray absorbing members 47a to 47d and the empty opening 46a is located in the X-ray optical path X0 are conceivable and are not limited to specific ones. For example, a method is conceivable in which the rotation drive device 54 is constituted by a pulse motor, and the disk 44 is rotated by a desired angle by controlling a pulse applied to the pulse motor.
[0038]
Another possible method is to attach a pulse generator to the shaft 43 and detect the rotation angle of the disc 44 using this pulse generator. A method is also conceivable in which a cam is provided corresponding to each opening 46, and when any opening 46 arrives in the X-ray optical path X0, the corresponding cam is detected by a microswitch.
[0039]
The operation of the rotary drive device 54 is controlled by the control device 56 of FIG. 4 is transmitted to the control device 56 in FIG. 1 and used as information for control by the control device 56. The information on the angular position of the disc 44 in FIG. .
[0040]
A tube 14 is disposed between the first slit 8 and the second slit 9, a tube 16 is disposed between the second slit 9 and the attenuator 41, and between the attenuator 41 and the third slit 11. Is provided with a tube 17, and a tube 18 is provided between the position where the sample S is mounted and the position where the detector plate 13 is placed. In the small angle scattering measurement, the detector plate 13 is disposed so as to face the end of the tube 18. These tubes 14, 16, 17, 18 are connected to a decompression device (not shown), and the inside of these tubes is decompressed to a vacuum or a decompressed state close thereto by the action of this decompression device. This reduced pressure state can prevent X-rays traveling in the tube from being attenuated by air scattering.
[0041]
In the small angle scattering device 1 of the present embodiment, the purpose is to detect the scattered radiation generated from the sample S supported by the sample support device 12, but the intensity of the scattered radiation is very small. The reason why the decompression passage is formed by the tubes 14, 16, 17, and 18 as described above is to prevent the scattered radiation from the target sample S from being disturbed by the X-ray air scattering.
[0042]
A stopper plate 48 is attached to the end of the pipe 18 so as to be slidable as indicated by arrows B and B ′. The stopper plate 48 includes a frame 49 formed in a ring shape of a square, a rectangle, a circle, or other appropriate shape, an X-ray transmission film 51 attached to the frame 49, and a substantially central position of the X-ray transmission film 51. The direct beam stopper 38 is fixed, for example, bonded to the direct beam stopper 38. The direct beam stopper 38 is made of, for example, Pb (lead).
[0043]
A mechanism for slidingly moving the stopper plate 48 is built in the end portion of the pipe 18 to which the stopper plate 48 is attached. Further, a lever 52 is attached to this slide mechanism. If the lever 52 is tilted in the direction of arrow C, the stopper plate 48 can be slid in the direction of arrow B. If the lever 52 is tilted in the direction of arrow C ′, the stopper plate 48 can be slid in the direction of arrow B ′.
[0044]
In this embodiment, when the lever 52 is moved to the extreme end position in the arrow C direction, the stopper plate 48 can be moved to the extreme end position in the arrow B direction, and the direct beam stopper 38 is moved to the X-ray optical path at this extreme end position. It is located on X0. Further, if the lever 52 is moved in the direction of the arrow C ′, the stopper plate 48 can be slid in the direction of the arrow B ′, and the direct beam stopper 38 can be retracted to the retracted position outside the X-ray optical path X0.
[0045]
As described above, the stopper plate 48, the mechanism for sliding the stopper plate 48, and the lever 52 are stopper position adjusting means for moving the direct beam stopper 38 between the position on the X-ray optical path X0 and the position retracted therefrom. Is configured. Of course, the stopper position adjusting means may have other configurations.
[0046]
A mechanism or lever 52 for sliding the stopper plate 48 is provided with a position sensor 53 of any structure such as a photo sensor, a micro switch, and the direct beam stopper 38 on the X-ray optical path X0. A different signal is output from the position sensor 53 according to the difference from the case of retreating from the X-ray optical path X0.
[0047]
FIG. 2 schematically shows the progress of X-rays in the small angle scattering device 1 shown in FIG. 2, the same reference numerals as those in FIG. 1 denote the same elements. As shown in FIG. 2, the confocal mirror 7 has two X-ray reflecting surfaces 7a and 7b that are in a crossing relationship with each other, and the X-rays reflected by these X-ray reflecting surfaces have the same or substantially the same focus f. It is an X-ray reflection mirror that is adapted to be gathered together.
[0048]
The confocal mirror 7 can be formed as a single layer structure with a material capable of reflecting X-rays, for example, nickel, platinum, tungsten, or the like. Alternatively, the confocal mirror 7 can also be formed as a multilayer mirror having a structure that reflects X-rays as a whole by using diffraction of X-rays by laminating a plurality of thin films on the X-ray reflecting surface. According to this multilayer mirror, X-rays with higher intensity can be reflected and collected at the focal point f as compared with the X-ray reflecting mirror having a single layer structure.
[0049]
The control device that controls the overall operation of the small angle scattering device 1 of FIG. 1 includes the control device 56 or is provided separately from the control device 56. However, this control device has at least the measurement mode and setting. There are three control modes: mode and X-ray monitor mode. These modes can be instructed by a keyboard, mouse, or other appropriate operation input device.
[0050]
The measurement mode is a control mode for irradiating the sample S with X-rays and measuring scattered X-rays generated from the sample S within a small-angle region with respect to the center of the X-ray optical path X0. The X-ray monitor mode is a control mode for checking whether X-rays are emitted from the X-ray source 4.
[0051]
The setting mode is formed by various optical elements disposed between the X-ray source 4 and the direct beam stopper 38, for example, the confocal mirror 7, the slits 8, 9, 11 and the sample support device 12. This is a control mode for checking whether or not the X-ray optical system is aligned with a predetermined position with respect to the X-ray optical path X0. The setting mode also includes checking whether the direct beam stopper 38 is accurately positioned on the X-ray optical path X0.
[0052]
(Measurement mode)
First, the operation in the measurement mode will be described. In this measurement mode, the measurer moves the lever 52 for the stopper plate 48 with an arrow. C The direct beam stopper 38 is set on the X-ray optical path X0 with the end position set in the direction. The detector plate 13 is disposed on the X-ray optical path X0. When the lever 52 is set at the above position, the position information is transmitted to the control device 56 by the position sensor 53. The control device 56 controls the operation of the attenuator 41 and the X-ray shutter 57 according to the information. That is, the state of the attenuator 41 and the X-ray shutter 57 is controlled in conjunction with the position of the direct beam stopper 38.
[0053]
Specifically, information indicating that the X-ray absorbing members 47a to 47b are not interposed in the X-ray optical path X0 is transmitted to the rotary drive device 54 in the attenuator 41 of FIG. And the empty opening 46a is set on the X-ray optical path X0. That is, the attenuator 41 is set in a state that does not attenuate X-rays. Further, the X-ray shutter 57 of FIG. 1 is set in a state in which the X-ray passage is opened and the X-ray is allowed to pass.
[0054]
Under the above conditions, the measurer attaches the sample holder 42 on which the sample S is mounted to a predetermined position of the sample support device 12, and sets the sample S on the X-ray optical path X0. Next, when a measurement start is instructed by the measurer, X-rays are generated from the X-ray source 4 and the X-rays proceed so as to be condensed at the focal point f by the confocal mirror 7 in FIG. In addition, the double slit structure of the first slit 8 and the second slit 9 sets the X-ray convergence state to a stable state, and further, the parasitic scattered radiation generated in the second slit 9 hits the sample S. This is prevented by the three slits 11.
[0055]
When the X-rays that have passed through the third slit 11 enter the sample S, in FIG. 3, scattered radiation having an intensity corresponding to the molecular structure is generated at a scattering angle 2θ corresponding to the molecular structure of the sample S. Then, an energy latent image corresponding to the intensity of the scattered radiation is accumulated on the detector plate 13 where the scattered radiation has hit.
[0056]
In FIG. 3, a direct beam stopper 38 is disposed in front of the detector plate 13 of the portion W0 where the direct beam Rd hits to prevent the direct beam Rd from hitting the detector plate 13 directly. A region indicated by W1 indicates a region where the parasitic scattered rays generated in the second slit 9 in FIG. 2 cannot be blocked by the third slit 11 and reach the detector plate 13.
[0057]
That is, the region W0 and the region W1 on the detector plate 13 are regions where the scattered radiation from the sample S cannot be measured due to the direct beam or the parasitic scattered radiation. Therefore, the small angle region measured by the small angle scattering device 1 of the present embodiment is a 2θ region outside W1 in FIG. 3, specifically, an angle region of 0.08 ° to 4.5 °. .
[0058]
The measurement of the scattered radiation in such a small-angle region must be performed with the X-rays being focused very small by the slits 8, 9, and 11 and the camera length L being further increased. Therefore, a general wide-angle goniometer is used. This cannot be realized by the X-ray measurement performed. In addition, since the intensity of the X-ray incident on the sample S is reduced due to the narrowing of the X-ray, it tends to require a long time for the measurement.
[0059]
However, in the present embodiment, as shown in FIG. 2, the X-rays emitted from the X-ray source 4 are condensed by the confocal mirror 7, so that X-rays having a stronger intensity than before are applied to the sample S. It can be made incident. Since high-intensity X-rays can be incident on the sample S in this way, in this embodiment, scattered light with sufficient intensity can be obtained on the detector plate 13 in a very short time. Measurement can be completed in a short time.
[0060]
After completion of the above measurement, in FIG. 1, the measurer removes the detector plate 13 from the small angle scattering device 1 and sets the detector plate 13 at a predetermined reading position of an X-ray reader (not shown). Then, the entire surface of the energy storage surface of the detector plate 13 is scanned with stimulated excitation light, for example, laser light, the light excited by this laser light is collected, and further converted into an electrical signal by a photoelectric tube or the like. Based on the signal, the scattering angle 2θ of the scattered radiation generated from the sample S and the intensity of the battle line are measured.
[0061]
(Setting mode)
Next, the operation in the setting mode will be described. This setting mode is usually executed in accordance with a measurement person's instruction prior to performing the above measurement mode, if necessary. In this setting mode, in FIG. 1, a mode for adjusting the position state of the X-ray optical system composed of various elements installed from the X-ray source 4 to the front side of the direct beam stopper 38, and a direct beam stopper. There are two types of modes for adjusting the position of 38.
[0062]
(1) First, settings regarding the X-ray optical system on the front side of the direct beam stopper 38 will be described. In the case of this setting, the measurer removes the detector plate 13 from the small angle scattering apparatus 1 and installs the 0-dimensional X-ray detector 15 on the X-ray optical path X0 instead. Further, the sample support device 12 is not loaded with the sample S.
[0063]
Further, the lever 52 of the direct beam stopper 38 is moved to the extreme end position in the arrow C ′ direction, the stopper plate 48 is slid in the arrow B ′ direction, and the direct beam stopper 38 is removed from the X-ray optical path X0. Move to. In this way, when the direct beam stopper 38 is retracted to the retracted position, the position information is transmitted to the control device 56 by the position sensor 53, and the control device 56 controls the attenuator 41 and the X-ray shutter in conjunction with the information. To do.
[0064]
Specifically, the rotation drive device 54 of FIG. 4 is controlled to rotate the disk 44 by an appropriate angle, and any one of the X-ray absorbing members 47a to 47d is set on the X-ray optical path X0. . Which X-ray absorbing member is selected is determined according to how much the X-ray intensity is attenuated. Since the X-ray emitted from the X-ray source 4 is attenuated by one of the X-ray absorption plates 47a to 47d, even when the direct beam stopper 38 is out of the X-ray optical path X0, the X-ray detector 15 has high intensity. Strong X-rays can be prevented from entering by mistake, and damage to the X-ray detector 15 can be prevented.
[0065]
In addition, the control device 56 sets the X-ray shutter 57 in an open state in conjunction with the direct beam stopper 38 being retracted to a position that is out of the X-ray optical path X0. Thereby, X-rays can be passed through the X-ray optical system including the slits 8, 9, 11 and the like. If the X-rays thus passed are attenuated by any of the X-ray absorbing members 47a to 47d in the attenuator 41 and then detected at a predetermined intensity by the X-ray detector 15, the slits 8, 9, 11 It is confirmed that the X-ray optical system including etc. is arranged at a regular position.
[0066]
On the other hand, when the X-ray detector 15 does not detect X-rays having a predetermined intensity, it can be determined that any element constituting the X-ray optical system is not placed at a normal position. Setting is performed by adjusting the position of the slit 8.9.11 or other elements according to the determination result.
[0067]
(2) Next, a mode for aligning the position of the direct beam stopper 38 will be described. In this mode, the measurer sets the lever 52 for the stopper plate 48 at the extreme end position in the arrow C direction, and places the direct beam stopper 38 on the X-ray optical path X0. In this way, the control device 56 links any of the X-ray absorbing members 47a to 47d in the attenuator 41 of FIG. 4 on the X-ray optical path X0 in conjunction with it. Further, the X-ray shutter 57 is arranged in an open state, that is, a state in which X-rays pass.
[0068]
In this state, X-rays are generated from the X-ray source 4 and detected by the X-ray detector 15. If the direct beam stopper 38 is set at a proper position, the X-ray detector 15 does not detect X-rays. On the other hand, if the direct beam stopper 38 is not set at the normal position, the X-ray detector 15 detects X-rays leaking from the direct beam stopper 38. Thus, it can be determined whether or not the direct beam stopper 38 is set at the normal position depending on whether or not the X-ray detector 15 detects X-rays.
[0069]
(X-ray monitor mode)
Next, the operation in the X-ray monitor mode will be described. This X-ray monitor mode is normally executed in accordance with a measurement person's instruction prior to performing the measurement mode or the setting mode as necessary.
[0070]
During this X-ray monitoring, the measurer tilts and moves the lever 52 of the stopper plate 48 to the extreme end position in the direction of the arrow C ′, and sets the direct beam stopper 38 at the retracted position that deviates from the X-ray optical path X0. When the direct beam stopper 38 is set in the retracted position in this way, the control device 56 interlocks with it and sets any one of the X-ray absorbing members 47a to 47d on the X-ray optical path X0 in the attenuator 41 of FIG. To do. Further, the control device 56 opens the X-ray shutter 57 in conjunction with the control device 56 and allows the passage of X-rays.
[0071]
When X-rays are generated from the X-ray source 4 in the above state, the intensity of the X-rays is attenuated by any of the X-ray absorbing members 47a to 47d of the attenuator 41, and the attenuated X-rays are converted into X-rays. It is detected by the detector 15. If X-rays are detected by the X-ray detector 15 in this way, it can be recognized that X-rays are emitted from the X-ray source 4. On the other hand, if the X-ray detector 15 does not detect X-rays, it can be recognized that X-rays are not emitted from the X-ray source 4.
[0072]
As described above, according to the present embodiment, the movement of the direct beam stopper 38, the movement of the attenuator 41, and the movement of the X-ray shutter 57 are linked to each other. Therefore, it is possible to surely prevent the X-ray detector 15 from being damaged by excessive X-rays entering the X-ray detector 15.
[0073]
(Other embodiments)
The present invention has been described with reference to the preferred embodiments. However, the present invention is not limited to the embodiments, and various modifications can be made within the scope of the invention described in the claims.
[0074]
For example, in the embodiment of FIG. 1, the direct beam stopper 38 is manually moved by the measurer between the position on the X-ray optical path X0 and the retracted position. Matching can also be performed automatically by the control device 56.
[0075]
In the embodiment of FIG. 1, the present invention is applied to a small angle scattering apparatus. However, the present invention can also be applied to an X-ray analysis apparatus other than the small angle scattering apparatus, for example, an X-ray analysis apparatus using a wide angle goniometer. .
[0076]
【The invention's effect】
As described above, according to the present invention, the X-ray attenuating element and the direct beam stopper can be moved in conjunction with each other. Therefore, when one is retracted to a position outside the X-ray optical path, the X-ray attenuation element and the direct beam stopper are linked with each other. The other can be automatically placed on the X-ray optical path. As a result, the X-rays traveling along the X-ray optical path always strike either the X-ray attenuation element or the direct beam stopper. Therefore, even when an X-ray detector is disposed on the X-ray optical path, it is possible to reliably prevent the X-ray having strong intensity from entering the X-ray detector.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of an X-ray analyzer according to the present invention.
FIG. 2 is a diagram schematically showing the progress of X-rays in the X-ray analyzer of FIG.
FIG. 3 is an enlarged view showing a main part of FIG. 2;
4 is a diagram showing an example of an internal structure of an attenuator that is a main part of the X-ray analysis apparatus of FIG. 1;
[Explanation of symbols]
1: small angle scattering device, 4: X-ray source, 6: X-ray tube, 7: confocal mirror, 8, 9, 11: slit, 12: sample support device, 13: detector plate (two-dimensional X-ray detector) , 14, 16, 17, 18: tube, 38: direct beam stopper, 41: attenuator (X-ray intensity adjusting means), 42: sample holder, 43: rotating shaft, 44: disc, 46: opening, 46a: Empty opening, 47a to 47d: X-ray absorbing member (X-ray attenuation element), 48: Stopper plate (stopper position adjusting means), 51: X-ray transmission film, 52: Lever, 53: Position sensor, 57: X-ray Shutter

Claims (4)

An X-ray source generating X-rays;
An X-ray attenuation element that allows X-rays to pass therethrough with a reduced intensity;
X-ray intensity adjusting means for selectively realizing a state where the X-ray attenuation element is placed on the X-ray optical path and a state where the X-ray attenuation element is not placed;
Sample support means for holding the sample to be analyzed;
A direct beam stopper for preventing the progress of the direct beam emitted from the X-ray source;
Stopper position adjusting means for moving the direct beam stopper between a position on the X-ray optical path and a retracted position retracted therefrom;
X-ray detection means disposed behind the direct beam stopper as viewed from the X-ray source;
Control means for moving the X-ray attenuation element and the direct beam stopper in conjunction with each other;
An X-ray shutter that selects a state of emitting X-rays from the X-ray source and a state of shielding X-rays;
The X-ray attenuating element and the direct beam stopper are interlocked so that the X-ray shutter shields the X-ray when both the X-ray attenuation element and the direct beam stopper are not on the X-ray optical path. Analysis equipment. In claim 1,
The control means has a measurement mode which is a control mode for performing X-ray measurement,
In the measurement mode, the control means places the direct beam stopper on an X-ray optical path, and links the X-ray attenuation element at a retracted position in conjunction with the direct beam stopper. In claim 2,
The control means has a setting mode which is a control mode for setting the X-ray optical system,
In the setting mode, the control means places the X-ray attenuation element on an X-ray optical path. In claim 2 ,
The control means has an X-ray monitor mode which is a control mode for checking whether or not X-rays are emitted.
In the X-ray monitor mode, the control means places the direct beam stopper at a retracted position and places the X-ray attenuation element on the X-ray optical path in conjunction with the direct beam stopper.

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