Method and its apparatus for x-ray diffraction

In order to realize a compact and lightweight X-ray diffraction apparatus not requiring a goniometer, an apparatus for X-ray diffraction includes a first X-ray irradiating unit and a second X-ray irradiating unit that irradiate shaped X-rays on a same region of the surface of the sample from respective directions; an X-ray detecting unit that detects a first diffracted X-ray emanated from the region of the sample where the X-ray is irradiated by the first X-ray irradiating unit and a second diffracted X-ray emanated from the region of the sample where the X-ray is irradiated from the second X-ray irradiating unit; and an X-ray diffraction signal processing unit that processes a signal acquired by detecting the first diffracted X-ray and the second diffracted X-ray emanated from the same region of the sample with the X-ray detecting unit.

TECHNICAL FIELD

The present invention relates to a method for X-ray diffraction in which a characteristic X-ray emitted from an X-ray tube is irradiated to a sample to make an analysis of a material, a portable method for X-ray diffraction using the same, and its apparatus.

BACKGROUND ART

A use of a method for X-ray diffraction has been established as a method of identifying an unknown crystal sample, or as a measurement method of measuring a part of a large sample or a sample mounted on various substrates. With this, there has been an increased demand for a measuring apparatus that can allow an analyzing apparatus, which has conventionally been used in a building, to be used outdoors. Thanks to the recent development in electronic techniques, a power source and a control circuit can be made compact, and lightweight, and can be formed to have reduced power consumption. However, a general method for X-ray diffraction entails a problem that, when a position of a sample is shifted from a predetermined position, a measurement precision or sensitivity is deteriorated. In order to avoid this situation, a mechanical angle measuring device called goniometer described in Patent Literature 1, for example, is used to carry out a measurement of an X-ray diffraction in which a sample is located at a predetermined position.

Patent Literature 2 describes a configuration of using a position-sensitive X-ray detector or accumulative fluorescent material, wherein a diffracted X-ray from a sample is detected with the detector being fixed.

Patent Literature 3 describes a configuration in which a direction of a CCD having position resolution within a linear range is changed between a tangential direction and a radius direction of a Debye ring of a diffracted X-ray so as to detect an intensity of the X-ray.

On the other hand, Patent Literature 4 describes a portable X-ray diffraction apparatus that aims an X-ray diffraction of a specific portion.

CITATION LIST

SUMMARY OF INVENTION

Technical Problem

In the measurement of the X-ray diffraction, a diffraction intensity of an X-ray to a diffraction angle of the X-ray is measured by an X-ray detector. Therefore, as described in Patent Literature 1, it has to be measured by changing the angle of the sample or the position of the detector for each angle. Accordingly, a mechanical angle measuring device inevitably needs weight in order to attain precision in holding an X-ray source or detector or in changing the angle, which means it is difficult to make the angle measuring device compact and lightweight.

In the X-ray diffraction apparatus described in Patent Literature 2, a position-sensitive X-ray detector is arranged over a wide detection-angle range. However, an incident angle (irradiation angle) of the X-ray to the sample is fixed, so that it is unsuitable for the detection of an X-ray diffraction pattern of a sample in which a direction of a crystal is optional.

The X-ray diffraction apparatus described in Patent Literature 3 has two types of detectors for detecting the tangential direction and radius direction of the Debye ring, wherein these detectors are switched for the detection. Therefore, it is unsuitable for making the apparatus compact.

Patent Literature 4 describes a hand-held X-ray diffraction apparatus. In this apparatus, two detectors are arranged at positions apart from each other, so that the Debye ring in a continuous region cannot be detected, which entails a problem that some information of the diffracted X-ray might be missing.

The present invention is accomplished in order to realize a compact and lightweight apparatus for X-ray diffraction as described above. Specifically, when an X-ray diffraction measurement is carried out, the measurement has conventionally been made under the condition in which a positional relationship among an incident X-ray, a sample, and a diffracted X-ray is surely retained. For example, a diffracted X-ray from a sample is measured by using a characteristic X-ray (when a target is Cu, a wavelength of Kα1is 0.154056 nm) emitted from an X-ray tube. This measurement condition is based upon Bragg law, wherein a mechanical angle setting device called goniometer has been used in order to accurately keep the positional relationship among the X-ray tube, the sample, and the X-ray detector. The mechanical goniometer has large weight, so that it is unsuitable as a device that can be held and used with human power. Further, since it is held by human power, the measurement is not affected by a shift in the position of the sample. Therefore, a method for X-ray diffraction, which is executed without using the goniometer, and an X-ray diffraction apparatus using this method have been desired.

The present invention is accomplished in view of the above-mentioned conventional problems, and aims to provide a method for X-ray diffraction that does not need a goniometer, which is used to adjust a position of a detector, and a compact and lightweight apparatus for this method.

Solution to Problem

In order to attain the foregoing object, the present invention provides an X-ray diffraction apparatus, the apparatus including: plural X-ray irradiating units that irradiate shaped X-rays onto a same surface of a sample from different directions; an X-ray detecting unit that detects plural diffracted X-rays emanated from the sample through the irradiation of the X-rays in the same surface region of the sample by the plural X-ray irradiating units; and an X-ray diffraction signal processing unit that processes signals acquired by detecting the plural diffracted X-rays emanated from the same surface region of the sample by the X-ray detecting unit.

In order to attain the foregoing object, the present invention also provides an X-ray diffraction method including: irradiating X-rays, which are shaped, from plural X-ray irradiating units onto a same surface of a sample from different directions; detecting, by an X-ray detecting unit, plural diffracted X-rays emanated from the sample through the irradiation of the X-rays in the same surface region of the sample by the plural X-ray irradiating units; and processing signals acquired by detecting the plural diffracted X-rays emanated from the same surface region of the sample by the X-ray detecting unit.

Advantageous Effects of Invention

According to the present invention, the X-ray diffraction pattern can be detected in a continuous wide region, whereby a higher detection precision can be attained.

The present invention does not need a goniometer conventionally used for adjusting a position of a detector, and does not have a movable mechanism other than a shutter. Therefore, the present invention can provide a compact and lightweight apparatus.

DESCRIPTION OF EMBODIMENTS

In the present invention, a position of a diffracted X-ray is detected without using a goniometer, whereby an apparatus is made compact and lightweight, which enhances portability.

First Embodiment

FIG. 1illustrates a configuration of a first embodiment.

An X-ray diffraction apparatus100according to the first embodiment includes an X-ray diffraction apparatus body101having a first X-ray irradiating unit110, a second X-ray irradiating unit120, an X-ray detector130, and a monitor camera140; a processing control unit150; and an output unit160. The first X-ray irradiating unit110, the second X-ray irradiating unit120, and the X-ray detector130are arranged on the same plane illustrated inFIG. 1.

The first X-ray irradiating unit110of the X-ray diffraction apparatus body101includes a first X-ray source111, a first shutter112, a first actuator113that drives the first shutter112to open or close the shutter112, and a first slit device114that narrows down the X-ray emitted from the first X-ray source111.

The second X-ray irradiating unit120of the X-ray diffraction apparatus body101includes a second X-ray source121, a second shutter122, a second actuator123that drives the second shutter122to open or close the shutter122, and a second slit device124that narrows down the X-ray emitted from the second X-ray source121.

The X-ray detector130is made of a two-dimensional sensor array having sensor devices, which detect the X-ray, arranged two-dimensionally.

The slit device is one of X-ray forming units, and it can be replaced with an X-ray optical device such as a capillary tube, zone plate, or a collimator. Specifically, the first slit device is a first X-ray forming unit, and the second slit device is a second X-ray forming unit. The same is applied to later-described embodiments 2 and 3.

The first X-ray irradiating unit110, the second X-ray irradiating unit120, and the X-ray detector130are arranged and fixed in a container102.

The container102is formed with an X-ray transmissive window103for irradiating the X-rays emitted from the first X-ray irradiating unit110and the second X-ray irradiating unit120arranged therein to a sample10placed at the outside of the container102. The X-ray transmissive window103may be a mere opening or may be partitioned with an X-ray transmissive film. When the X-ray transmissive window103is partitioned with the X-ray transmissive film, the container102can be evacuated or filled with an inert gas with an unillustrated unit.

In order to be capable of confirming, by the monitor camera140, the position of the sample10where the X-ray is irradiated, a glass window104for the monitor is provided at the side where the monitor camera140is mounted. An X-ray shield ring105for a protection of an X-ray leakage is provided at the outside of the X-ray transmissive window103in order to prevent the X-ray from leaking to the outside of the container102, when the X-ray emitted from the first X-ray irradiating unit110or the second X-ray irradiating unit120is irradiated to the sample10.

As illustrated inFIG. 2, the processing control unit150includes a first X-ray source drive unit151for driving the first X-ray source111, a first shutter drive unit152for driving the first actuator113so as to open and close the first shutter112, a camera control unit153for controlling the monitor camera140, a second shutter drive unit154for driving the second actuator123so as to open and close the second shutter122, a second X-ray source drive unit155for driving the second X-ray source121, a sensor input unit156for receiving an output from the X-ray detector130, an operation unit157for calculating an X-ray diffraction angle of the sample10by using the output from the X-ray detector130received by the sensor input unit156, an input/output unit158that inputs information involved with the irradiation condition of the X-ray and the sample10and outputs information involved with the X-ray diffraction angle of the sample10obtained from the operation unit157, and an entire control unit159that controls the entire apparatus. The respective units of the processing control unit150and the X-ray diffraction apparatus body101are separated, wherein they are connected with a cable106.

The output unit160includes a display screen161, and displays the information involved with the X-ray diffraction angle of the sample10outputted from the input/output unit158of the processing control unit150onto the display screen161.

A method of measuring the diffraction of the X-ray of the sample10with the configuration described above will be described with reference toFIGS. 3 to 5.

As illustrated inFIG. 3A, when the X-ray having a wavelength of λ from the first X-ray source111is transmitted through the first slit device114to be shaped, and then, is incident on the sample10, which is a polycrystalline body, with an incident angle φ1, the diffracted X-ray is emanated according to the orientation of the crystal of the sample10. When the diffraction angle of the diffracted X-ray with respect to the advancing direction of the incident X-ray is defined as2θ1, the diffracted X-ray appears on an annular outline (Debye ring) obtained by cutting a cone, in which the incident direction of the X-ray is defined as a central axis and a half of an apex angle is defined as2θ1with the position of the sample10where the X-ray is irradiated being defined as an apex, along a plane vertical to the central axis.

The diffraction angle2θ1is represented as an angle double the incident angle θ1of the X-ray to the crystal plane of the sample10. Specifically, when the position where the diffracted X-ray is emanated is found through the detection of the diffracted X-ray from the sample10with the use of the X-ray detector130, information relating to a crystal lattice length of the sample10can be obtained from the incident angle of the X-ray to the sample10and the relating to the position where the diffracted X-ray is emanated. When the crystal plane of the sample10has random orientations, information relating to the respective crystal planes can be obtained, whereby the inside of the sample10can be observed without destroying the sample10.

FIG. 3Billustrates one example of a state in which the diffracted X-ray from the sample10is detected by the X-ray detector130. Diffracted X-ray patterns111-1to111-4according to the indexing of the crystal planes of the sample10are detected on the detection surface of the X-ray detector130.

The diffraction angle2θ1, θ1of the diffracted X-ray and the crystal lattice length can be obtained from the positional relationship among the positional information of the convex diffracted X-ray patterns111-1to111-4on the X-ray detector130detected by the X-ray detector130, the position of the sample10where the X-ray is irradiated and the X-ray detector, and the information relating to the X-ray irradiation direction.

It has been described that the X-ray detector130is a two-dimensional detector. However, the X-ray detector30may be replaced with a linear sensor having devices arranged in a longitudinal direction as illustrated inFIG. 3A, because the position of the Debye ring of the diffracted X-ray projected on the X-ray detector130is only found.

As illustrated inFIG. 4A, when the X-ray having a wavelength of λ, same as the wavelength of the X-ray from the first X-ray source111, from the second X-ray source121is transmitted through the second slit device124to be shaped, and then, is incident on the region on the polycrystalline sample10, which region is the same as the region where the X-ray from the first X-ray source111is irradiated, with an incident angle φ2, the diffracted X-ray is emanated according to the lattice indexing of the crystal of the sample10. When the diffraction angle of the diffracted X-ray with respect to the advancing direction of the incident X-ray is defined as2θ2, the diffraction angle2θ2is represented as an angle double the incident angle θ2of the X-ray to the crystal plane of the sample10. When the crystal plane of the sample10has random orientations, information relating to the respective crystal planes can be obtained, whereby the inside of the sample10can be observed without destroying the sample10.

FIG. 4Billustrates one example of a state in which the diffracted X-ray from the sample10is detected by the X-ray detector130. Diffracted X-ray patterns according to the indexing of the crystal plane of the sample10are detected on the detection surface of the X-ray detector130. Since the incident angle θ2of the X-ray from the second X-ray source121to the sample10is different from the incident angle θ1of the X-ray from the first X-ray source111to the sample10, the concave patterns121-1to121-4of the diffracted X-ray on the detection surface of the X-ray detector130are detected such that the direction of the curvatures is opposite to the direction of the curvatures of the convex patterns111-1to111-4of the diffracted X-ray illustrated inFIG. 3B.

The diffraction angle2θ2and θ2of the diffracted X-ray and the crystal lattice length can be obtained from the positional relationship among the positional information of the diffracted X-ray patterns121-1to121-4on the X-ray detector130detected by the X ray detector130, the position of the sample10where the X-ray is irradiated and the X-ray detector, and the information relating to the X-ray irradiation direction. In this case, the X-ray detector130can be replaced with a linear sensor.

When the X-ray from the first X-ray source111and the X-ray from the second X-ray source121are simultaneously irradiated to the same region of the sample10, the X-ray diffraction illustrated inFIG. 3Aand the X-ray diffraction illustrated inFIG. 4Aare simultaneously emanated from the sample10, so that the diffraction patterns111-1to111-4convex in shapes and the diffraction patterns121-1to121-4concave in shapes as illustrated inFIG. 5are detected by the X-ray detector130. The X-ray diffraction pattern illustrated inFIG. 5is a pattern formed by combining the convex diffraction patterns111-1to111-4generated by the irradiation of the X-ray from the first X-ray source111illustrated inFIG. 3Band the concave diffraction patterns121-1to121-4generated by the irradiation of the X-ray from the second X-ray source121illustrated inFIG. 4B.

In this case, the center direction of the curvature of each pattern is obtained from the output from the two-dimensional X-ray detector130detecting the X-ray diffraction patterns illustrated inFIG. 5, in order to separate the diffraction patterns111-1to111-4generated by the irradiation of the X-ray from the first X-ray source111and the diffraction patterns121-1to121-4generated by the irradiation of the X-ray from the second X-ray source121.

The diffraction angles2θ1, θ1,2θ2and θ2of the diffracted X-ray and the crystal lattice length can be obtained from the positional relationship among the positional information on the X-ray detector130of each of separated patterns, the position of the sample10where the X-ray is irradiated, and the X-ray detector130, and the X-ray irradiating direction.

The X-ray detector130is arranged as tilting with respect to the Debye ring formed by the diffraction patterns111-1to111-4generated by the irradiation of the X-ray from the first X-ray source111and the Debye ring formed by the diffraction patterns121-1to121-4generated by the irradiation of the X-ray from the second X-ray source121, whereby the X-ray diffraction patterns detected by the two-dimensional X-ray detector130are detected as an ellipse that is deformed from a true circle. Accordingly, when the diffraction angles2θ1, θ1,2θ2and θ2of the diffracted X-ray are obtained, they may be calculated by using information of the major axis of the ellipse that is extracted from the elliptic X-ray diffraction pattern detected by the two-dimensional X-ray detector130.

Next, the procedure of the operation of detecting the X-ray diffraction patterns by sequentially irradiating the X-ray onto the sample10from the first X-ray source111and the second X-ray source121with the use of the apparatus illustrated inFIG. 1will be described with reference toFIG. 6.

Firstly, the X-ray diffraction apparatus100is set on the sample10to be measured, and with this state, the surface of the sample10below the transmissive window103is observed by the camera140through the window portion104so as to confirm whether or not the portion of the sample10that should be analyzed agrees with the position where the X-ray is irradiated (S601). When the position is determined to be shifted as a result of the observation (NO in S602), the position of the X-ray diffraction apparatus100or the sample10is adjusted (S603).

When it is determined that the position is not shifted as a result of the observation (YES in S602), the first actuator113is driven according to the instruction from the first shutter drive unit152of the processing control unit150so as to open the first shutter112arranged immediately before the first X-ray source111(S604), whereby the X-ray emitted from the first X-ray source111is transmitted through the first slit device114to be narrowed down and shaped, and then, irradiated to the sample10below the X-ray transmissive window103. The diffracted X-ray, out of the diffracted X-rays emanated from the sample10to which the X-ray narrowed down by the first slit device114is irradiated, passing through the X-ray transmissive window103to be incident on the X-ray detector130is detected by the X-ray detector130(S605). The output from the X-ray detector130detecting the diffracted X-ray is inputted to the sensor input unit156of the processing control unit150, amplified, subjected to an A/D conversion, and then, transmitted to the operation unit157where the diffraction angle θ1is obtained through the operation process (S606).

Subsequently, the first actuator113is driven in accordance with the instruction from the first shutter drive unit152so as to close the first shutter112(S607), in order to shield the X-ray emitted from the first X-ray source111for preventing the X-ray from irradiating the sample10. The second actuator123is driven in accordance with the instruction from the second shutter drive unit154so as to open the second shutter122, which is arranged immediately before the second X-ray source121(S608), whereby the X-ray emitted from the second X-ray source121is transmitted through the second slit device124to be narrowed down and shaped, and then, irradiated to the region of the sample10, same as the region where the X-ray emitted from the first X-ray source111is irradiated, through the X-ray transmissive window103.

The diffracted X-ray, out of the diffracted X-rays emanated from the sample10to which the X-ray narrowed down by the second slit device124is irradiated, passing through the X-ray transmissive window103to be incident on the X-ray detector130is detected by the X-ray detector130(S609). The output from the X-ray detector130detecting the diffracted X-ray is inputted to the sensor input unit156of the processing control unit150, amplified, subjected to an A/D conversion, and then, transmitted to the operation unit157where the diffraction angle θ2is obtained through the operation process (S610).

Then, the second actuator123is driven in accordance with the instruction from the second shutter drive unit154to close the second shutter122(S611), in order to shield the X-ray emitted from the second X-ray source121for preventing the X-ray from irradiating to the sample10.

Finally, information of the θ1obtained in S606through the operation, θ2obtained in S610through the operation are sent to the output unit160from the input/output unit158, and the resultant is displayed onto the display screen161(S612).

According to the present embodiment, it takes some times because the X-ray is sequentially irradiated from the first X-ray source111and the second X-ray source121. However, the X-ray diffraction patterns generated by the irradiation of the X-ray from the first X-ray source111and the X-ray diffraction patterns generated by the irradiation of the X-ray from the second X-ray source121can be detected as being surely separated from each other, whereby a high detection precision can be expected without changing the position of the X-ray detector.

Since the X-ray diffraction patterns can be detected in a continuous wide region by a linear or two-dimensional X-ray detector130, a higher detection precision can be attained.

The X-ray detector130can be configured with a linear detector, and since the X-ray detector130is fixed, the apparatus does not have a movable mechanism other than the shutter. Therefore, the apparatus can be made compact and lightweight.

As a modification of the present embodiment, the on/off function of the drive source151for the first X-ray source111and the on/off function of the drive source155for the second X-ray source121can be used as a substitute operation of opening and closing the first shutter112and the second shutter122. In this case, the shutter can be eliminated from the apparatus.

As another modification of the present embodiment, a drive high-voltage power source unit (not illustrated) of the first X-ray source111and the second X-ray source121can be shared, and it is electrically changed by a switch, whereby the weight of the apparatus can further be reduced.

The present embodiment does not need a goniometer conventionally used for adjusting a position of the X-ray detector, and does not have a movable mechanism other than the shutter. Therefore, the present embodiment can provide a compact and lightweight apparatus.

Second Embodiment

A second embodiment will be described below wherein the X-ray is simultaneously emitted from the first X-ray source111and the second X-ray source121so as to simultaneously irradiate the same region on the sample10with the use of the X-ray diffraction apparatus100having the configuration illustrated inFIG. 1. In this case, the pattern, as described inFIG. 5, is detected from the sample10, wherein the pattern has the X-ray diffraction patterns by the irradiation of the X-ray from the first X-ray source111and the X-ray diffraction patterns by the irradiation of the X-ray from the second X-ray source121, those of which are superimposed with each other.

The procedure of the detection in this case will be described with reference toFIG. 7.

Firstly, the X-ray diffraction apparatus100is set on the sample10to be measured, and with this state, the surface of the sample10below the transmissive window103is observed by the camera140through the window portion104so as to confirm whether or not the portion of the sample10that should be analyzed agrees with the position where the X-ray is irradiated (S701). When the position is determined to be shifted as a result of the observation (NO in S702), the position of the X-ray diffraction apparatus100or the sample10is adjusted (S703).

When it is determined that the position is not shifted as a result of the observation (YES in S702), the first actuator113is driven according to the instruction from the first shutter drive unit152of the processing control unit150so as to open the first shutter112arranged immediately before the first X-ray source111, and simultaneously, the second actuator123is driven according to the instruction from the second shutter drive unit154so as to open the second shutter122arranged immediately before the second X-ray source121(S704), whereby the X-ray emitted from the first X-ray source111and shaped by the first slit device114and the X-ray emitted from the second X-ray source121and shaped by the second slit device124are transmitted through the X-ray transmissive window103, and simultaneously irradiated onto the same region of the sample10.

The diffracted X-ray, out of the diffracted X-rays emanated from the sample10to which the X-ray is irradiated, passing through the X-ray transmissive window103to be incident on the X-ray detector130is detected by the X-ray detector130(S705). The output from the X-ray detector130detecting the diffracted X-ray is inputted to the sensor input unit156of the processing control unit150, amplified, subjected to the A/D conversion, and then, transmitted to the operation unit157where the X-ray diffraction patterns generated from the X-ray emitted from the first X-ray source111and the X-ray diffraction patterns generated from the X-ray emitted from the second X-ray source121are separated from each other (S706), and the diffraction angle θ1of the X-ray diffraction patterns generated by the X-ray emitted from the first X-ray source111and the diffraction angle θ2of the X-ray diffraction patterns generated by the X-ray emitted from the second X-ray source121are obtained through the operation process (S707).

Subsequently, the first actuator113is driven in accordance with the instruction from the first shutter drive unit152so as to close the first shutter112, and simultaneously, the second actuator123is driven in accordance with the instruction from the second shutter drive unit154so as to close the second shutter122(S708), in order to shield the X-ray emitted from the first X-ray source111and the X-ray emitted from the second X-ray source121.

Finally, the information of the θ1and θ2obtained in S707through the operation is sent to the output unit160from the input/output unit158, and the resultant is displayed onto the display screen161(S709).

According to the present embodiment, the X-rays are simultaneously irradiated from the first X-ray source111and the second X-ray source121, whereby the time for the measurement can be shortened.

The X-ray diffraction patterns can be detected in a continuous wide region with the two-dimensional X-ray detector130, whereby a higher detection precision can be attained.

Since the X-ray detector130is fixed, the apparatus does not have a movable mechanism other than the shutter. Therefore, the apparatus can be made compact and lightweight.

As a modification of the present embodiment, the on/off function of the drive source151for the first X-ray source111and the on/off function of the drive source155for the second X-ray source121can be used as a substitute operation of opening and closing the first shutter112and the second shutter122. In this case, the shutter can be eliminated from the apparatus.

The present embodiment does not need a goniometer conventionally used for adjusting a position of the X-ray detector, and does not have a movable mechanism other than the shutter. Therefore, the present embodiment can provide a compact and lightweight apparatus.

Third Embodiment

A third embodiment according to the present invention will be described with reference toFIG. 8.

The configuration illustrated inFIG. 8is obtained by eliminating the monitor camera140of the X-ray diffraction apparatus100described inFIG. 1and mounting a third X-ray irradiating unit830. The elements which are the same with that of the first embodiment are put the same number with theFIG. 1. As in the first and second embodiments, an X-ray diffraction apparatus body801of the third embodiment includes the first X-ray irradiating unit110, the second X-ray irradiating unit120, the third X-ray irradiating unit830, and an X-ray detector840. These are arranged on the same plane in a container802illustrated inFIG. 8, wherein X-rays generated by the first to third X-ray irradiating units110,120, and830are transmitted through an X-ray transmissive window803to be irradiated onto the sample10.

As illustrated inFIG. 9, a processing control unit850includes the first X-ray source drive unit151for driving the first X-ray source111, the first shutter drive unit152for driving the first actuator113, the second shutter drive unit154for driving the second actuator123, the second X-ray source drive unit155for driving the second X-ray source121, a third X-ray source drive unit851for driving the third X-ray source831, a third shutter drive unit852for driving a third actuator833, a sensor input unit853for receiving an output from the X-ray detector840, an operation unit854for calculating an X-ray diffraction angle of the sample10by using the output from the X-ray detector840received by the sensor input unit853, an input/output unit855that inputs information relating to the irradiation condition of the X-ray and the sample10and outputs information relating to the X-ray diffraction angle of the sample10calculated by the operation unit854, and an entire control unit856that controls the entire apparatus. The respective units of the processing control unit850and the X-ray diffraction apparatus body801are separated, wherein they are connected with a cable806.

The output unit860includes a display screen861, and displays the information relating to the X-ray diffraction angle of the sample10outputted from the input/output unit855of the processing control unit850onto the display screen861.

Like the first X-ray irradiating unit110and the second X-ray irradiating unit120described inFIG. 1, the third X-ray irradiating unit830includes the third X-ray source831, the third shutter832, the third actuator833for driving the third shutter832for opening and closing the third shutter832, and a third slit device834for narrowing down the X-ray emitted from the third X-ray source831.

The method of detecting the diffracted X-ray from the sample10with the use of the apparatus800having the above-mentioned configuration is the same as the method of detecting the X-ray diffraction patterns by sequentially irradiating the X-ray from each X-ray source as described in the first embodiment, and the method, as described in the second embodiment, in which the X-rays are simultaneously irradiated from the respective X-ray sources, and the X-ray diffraction patterns detected by the two-dimensional X-ray detector130are separated into each X-ray diffraction pattern for each X-ray source so as to obtain the diffraction angle.

The present embodiment describes the case in which three X-ray irradiating units are provided. However, the present invention is not limited thereto. The X-ray diffraction apparatus may be configured to include many X-ray irradiating units more than three.

In the present embodiment, plural X-ray irradiating units, each having a different X-ray irradiation angle, are provided to irradiate the X-ray onto the sample. Therefore, the diffracted X-ray in a wider range can be detected, which can enhance the precision in the X-ray diffraction.

Since the X-ray diffraction patterns can be detected in a continuous wide region by the two-dimensional X-ray detector840, a higher detection precision can be attained.

When the present embodiment takes a method same as the method described in the first embodiment in which the X-ray is sequentially irradiated from each X-ray source so as to detect the X-ray diffraction patterns, a drive high-voltage power source unit (not illustrated) of the first X-ray source111, the second X-ray source121, and the third X-ray source831can be shared, and it is electrically changed by a switch, whereby the weight of the apparatus can further be reduced, as a modification of the present embodiment.

When the present embodiment takes a method same as the method described in the second embodiment in which the X-rays are simultaneously irradiated from the respective X-ray sources, the on/off function of the drive source151for the first X-ray source111, the on/off function of the drive source155for the second X-ray source121, and the on/off function of the drive source851for the third X-ray source831can be used as a substitute operation of opening and closing the first shutter121, the second shutter122and the third shutter832. In this case, the shutters can be eliminated from the apparatus, as another modification of the present embodiment.

The slit device is one of X-ray forming units, and it can be replaced with an X-ray optical device such as a capillary tube, zone plate, or a collimator. Specifically, the first slit device114is a first X-ray forming unit, the second slit device124is a second X-ray forming unit, and the third slit device834is a third X-ray forming unit.

The present embodiment does not need a goniometer conventionally used for adjusting a position of the X-ray detector, and does not have a movable mechanism other than the shutter. Therefore, the present embodiment can provide a compact and lightweight apparatus.

INDUSTRIAL APPLICABILITY

The present invention is applicable to a portable X-ray diffraction apparatus using a method for X-ray diffraction for analyzing a material by irradiating a characteristic X-ray, generated from an X-ray tube, onto a sample.

REFERENCE SIGNS LIST