X-ray analysis apparatus

Abstract

The present invention relates to an X-ray analysis apparatus comprising a first roller having a length, a second roller, the first roller and the second roller forming a sample plane along which a sample passes, an X-ray source for irradiating the sample with X-rays and configured, in operation, to project X-rays to a work area between the first and second rollers, a detector configured to detect X-rays, and an enclosure extending at least the length of the first roller and comprising a first and a second part. The first part is arranged on a first side of the sample plane opposite to the X-ray source and has a first opening adjacent the sample plane and a base distal the sample plane. The second part is arranged on a second side of the sample plane, the same side as the X-ray source, and has a second opening. The first opening and the second opening are complementary. At least one of the second part and at least the base of the first part is moveable between a first position, wherein the enclosure encloses the X-ray source and the detector, and a second position.

Description

[0001] X-RAY ANALYSIS APPARATUS

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to an apparatus and method for X-ray analysis. In particular, examples relate to an X-ray analysis apparatus of flat materials and thin films.

[0004] BACKGROUND

[0005] X-ray analysis methods can be used to characterise materials. Flat material and thin film X-ray analysis is a technique used to study the atomic and molecular structure of materials. The material to be inspected is prepared and then irradiated with X-rays and resulting signals then detected. Generally, two forms of signals can be detected and these detection methods are known as X-ray diffraction or X-ray fluorescence. In X-ray diffraction, the material scatters the X-rays and results in a diffraction pattern which is detected and can then be analysed to determine information about the crystal structure. In X-ray diffraction a detector is positioned at a location to which diffracted X-rays will be directed i.e. on the same side of the sample as the X-ray source. In X-ray fluorescence, the material emits characteristic fluorescent X-rays which are then detected. In fluorescence a detector may also be positioned on the same side of the sample as the X-ray source. In X-ray transmission measurements, the detector may be positioned on the other side of the sample to the X-ray source.

[0006] Information which can be determined from the detected X-rays include material content (including atomic composition), the spacing between crystal planes, the orientation of crystal planes, information about the unit cell and other lattice parameters. This analysis can be used to study layers of materials, investigate changes in crystal structure, for example under different conditions.

[0007] X-ray analysis of flat materials such as plate glass or pictures can also be carried out and can be used to examine characteristics or changes in the material under inspection.

[0008] In industrial applications, X-ray analysis is a non-destructive method of identifying defects, determining material thickness and assessing the content and properties of a material. In particular, it can be used in the quality control of materials to ensure that the material fulfils specific quality criteria. It can also be used to detect defects, cracks, inconsistencies or contamination of materials.

[0009] X-ray analysis is also used to determine the thickness and uniformity of layers such as in the production of photovoltaic cells. Finally, X-ray analysis can be used to analyse the structural properties and composition of materials such as semiconductors and other advanced materials used in electronic applications. X-ray using a roll to roll arrangement is a thin film X-ray analysis method which involves the X-ray inspection, either continuous or spot inspection, of materials on a roll of thin film. This is particularly useful in scenarios in which quality control and non-destructive testing are essential and examples of these include flexible electronics and membranes. Roll-to-roll X- ray analysis ensures the quality and consistency of the materials being processed without interrupting the production line.

[0010] One particular industrial application of roll-to-roll X-ray analysis methods and apparatus is in the production of catalyst-coated polymer electrolyte membranes in fuel cells. The electrocatalysts are capital intensive and inconsistent application, for example too much or too little of the active element, either wastes valuable resources or renders the catalyst ineffective. Careful monitoring of the material results in higher quality products and improved cost control.

[0011] The use of roll-to-roll X-ray analysis in scenarios such as the manufacture of membranes in fuel cells allows real-time monitoring of the materials for enhanced process control. The regular analysis means that material composition and loading are continually optimised which minimises off-specification production and maximises cost efficiencies.

[0012] In a roll-to-roll X-ray apparatus the thin film must initially be loaded into the apparatus. Furthermore, it may be necessary to access the apparatus for maintenance. However, doors are relatively small and it can therefore be difficult to access the thin film, or other parts, within a roll-to-roll X-ray analysis apparatus.

[0013] Flat materials, for example plate glass or paintings, may also be examined by X-ray analysis which can be used to detect defects in materials or historical features of pictures.

[0014] Accordingly, there is a need to provide an improved X-ray analysis apparatus that allows easier access to the working parts of the apparatus.

[0015] SUMMARY

[0016] According to an aspect of the invention there is provided an X-ray analysis apparatus comprising: a first roller having a length; a second roller, the first roller and the second roller forming a sample plane along which a sample passes; an X-ray source for irradiating the sample with X-rays and configured, in operation, to project X-rays to a work area between the first and second rollers; a detector configured to detect X-rays; an enclosure extending at least the length of the first roller and comprising a first part and a second part, wherein the first part is arranged on a first side of the sample plane, opposite to the X- ray source, and has a first opening adjacent the sample plane and a base distal the sample plane, wherein the second part is arranged on a second side of the sample plane, the same side as the X-ray source, and has a second opening, wherein the first opening and the second opening are complementary, and wherein at least one of the second part and at least the base of the first part is movable between a first position, wherein the enclosure encloses the X-ray source and the detector, and a second position.

[0017] This arrangement allows the sample to pass between the first and second parts of the enclosure. The enclosure contains radiation but yet is splittable which enables the sample and working parts to be accessed easily.

[0018] The enclosure is thus formed by the first part with an opening and the second part with an opening. The first opening of the first part and the second opening of the second part are generally arranged opposite each other and have a small gap therebetween. This small gap allows the sample to pass from outside the enclosure, into the enclosure. Thus, the enclosure contains the X-rays but the sample can pass into and out of the enclosure. Advantageously, according to the invention the enclosure can easily be opened and then closed.

[0019] The first opening and the second opening have a coefficient of congruence, in planes parallel to the sample plane, of 0.95 or more. More specifically, the first and second openings may have congruent shapes in planes parallel to the sample plane.

[0020] In an example, the second part may be movable perpendicularly to the sample plane between the first position and the second position. Preferably, the second part is configured to move a minimum of 150mm between the first and second positions.

[0021] The entire first part may be movable perpendicularly to the sample plane between the first position and the second position. Preferably, the first part moves a minimum of 150mm between the first and second positions.

[0022] The first part may comprise a first side wall and a second side wall, the first side wall having a first end proximal the sample plane, corresponding to the first opening, and a second end distal the sample plane, coupled to the base.

[0023] The base may be configured to rotate, between the first position and the second position, around a pivot on the first side wall. The pivot may be adjacent the second end of the first side wall. Alternatively, the pivot may be adjacent the first end of the first side wall, and the base may be configured to rotate, together with the first side wall, around said pivot.

[0024] In an example, the base and at least a portion of the first side wall and at least a portion of the second side wall are configured to rotate, together with the first side wall, around the pivot. Preferably, the base, the portion of the first side wall and the portion of the second side wall are configured to rotate around the combined centre of mass of the base, the portion of the first side wall and the portion of the second side wall.

[0025] In the first position the first opening is preferably a maximum distance of 150mm from the sample plane and the second opening is a maximum distance of 50mm from the sample plane.

[0026] The first and second parts, forming the enclosure are designed to confine radiation. Each of the first and second parts, at each of the first and second ends, may comprise an end portion perpendicular to the length of the roller. In order to restrict the X-rays the first and second parts comprise metal, preferably steel. The first and second parts comprise leaded glass.

[0027] In the first position, the first opening and the second opening are directly opposite each other in a direction perpendicular to the sample plane.

[0028] BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Examples of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

[0030] Figure 1a is a schematic diagram illustrating a roll-to-roll X-ray analysis apparatus according to the prior art;

[0031] Figure 1b depicts an alternative roll-to-roll X-ray analysis apparatus according to the prior art;

[0032] Figure 2a is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a first position;

[0033] Figure 2b is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a second position;

[0034] Figure 3a is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a first position;

[0035] Figure 3b is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a second position (horizontally translated second part);

[0036] Figure 4 is a schematic diagram illustrating an X-ray analysis apparatus according to another example of the invention;

[0037] Figure 5 is a schematic diagram illustrating an X-ray analysis apparatus according to another example of the invention;

[0038] Figure 6a is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a first position; Figure 6b is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a second position;

[0039] Figure 7 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0040] Figure 8a is a schematic diagram illustrating an X-ray analysis apparatus according to an example of the invention in a first position;

[0041] Figures 8b and 8c are schematic diagrams illustrating an X-ray analysis apparatus according to an example of the invention in a second position;

[0042] Figure 9 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0043] Figure 10 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0044] Figure 11 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0045] Figure 12 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0046] Figure 13a depicts an X-ray analysis apparatus in a first position;

[0047] Figure 13b depicts an X-ray analysis apparatus in a second position;

[0048] Figure 14 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0049] Figure 15 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention;

[0050] Figure 16 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention; and

[0051] Figure 17 is a schematic diagram illustrating a portion of an X-ray analysis apparatus according to another example of the invention

[0052] Figure 18a is a side view illustrating an X-ray analysis system according to another example of the invention; and

[0053] Figure 18b is a plan view of the apparatus depicted in Figure 13a

[0054] It should be noted that these figures are diagrammatic and not drawn to scale. Relative dimensions and proportions of parts of these figures have been shown exaggerated or reduced in size, for the sake of clarity and convenience in the drawings.

[0055] DETAILED DESCRIPTION Figure 1 depicts a prior art roll-to-roll X-ray apparatus. As can be seen there is a thin film 10 which is extended across a first roller 2, a second roller 3, a third roller 4 and a fourth roller 5. The rollers can facilitate movement of the thin film 10 which is driven by a roller elsewhere. Alternatively, one or more of the rollers may be driving rollers which drive the thin film.

[0056] The apparatus comprises an X-ray source 1, which generates X-rays. The X-ray source includes a cathode and an anode enclosed in a sealed housing. In use, the cathode emits an electron beam which is incident on a target surface of the anode, thereby irradiating an irradiated area of the anode.

[0057] The anode is configured to emit X-rays. The housing includes a window arranged to allow some X-rays emitted by the anode to exit the housing as a beam of X-rays. The X-ray source may further comprise an X-ray optic arranged to receive X-rays from the X-ray source.

[0058] The apparatus comprises rollers 2, 3 which help to move the thin film or sample. X- rays emitted by the source 1 are incident upon a work area of the thin film. At the thin film the X-rays are scattered and / or reflected by and / or transmitted through the sample material (thin film). The scattered and / or reflected X-rays are then detected by a detector. The detected results can be analysed to determine, for example, the thickness of, or inconsistencies in, the material deposited on the thin film, any defect in the material, etc. The detector may be part of a single unit with the X-ray source.

[0059] The X-rays may operate continuously to obtain data about the sample continuously or they may operate periodically to obtain information from, for example, each distinct manufactured unit.

[0060] The X-ray source and the rollers are located in a housing 8, which serves to contain the X-rays. The thin film enters through a thin slit on one side of the housing and exits through a thin slit on the opposite side of the housing. The housing may have a door which can (when not in operation) be opened in order to arrange the thin film initially. However, this is cumbersome and difficult.

[0061] Figure 1b depicts an alternative prior art apparatus. As can be seen there are a plurality of rollers, around and / or over which the thin film passes. The plurality of rollers can serve to keep the thin film taut. In this example, the X-ray source 1 is arranged at the end of an articulated arm 11. On each side is a door 15 which slide vertically upwards to open. These doors constrain the X-rays but, as can be seen, the door is relatively small and accessing the various parts of the inside of the housing can be difficult and time consuming.

[0062] Figure 2 depicts an example of the invention in which the top side of the rollers 2 and 3 form a sample plane, along which a film passes. The width of the thin film 10 passes along the length of the rollers 2, 3. Figure 2a depicts an apparatus according to an example of the invention with an enclosure formed of two parts: a first part 21 and a second part 22. The enclosure encloses the first and second rollers, the X-ray source and the detector and therefore forms an enclosed space in which radiation is contained. In Figures 2-11 the X-ray source and the detector are depicted as a single unit 1. However, they may be separate units Although the X-ray source and detector are, in this example, depicted on the same side of the thin film (suitable for both X-ray diffraction and X-ray fluorescence) they could equally be positioned on opposite sides of the thin film (e.g. for X-ray transmission measurements).

[0063] The first part and the second part are both made of metal, in particular a metal which does not allow X-rays to pass. However, as will be appreciated by those skilled in the art, any material which provides a barrier to the X-rays may be utilised.

[0064] The first part has an opening 21a (also referred to as the first opening) and the second part has an opening 22a (also referred to as the second opening). The opening of the first part and the opening of the second part are shown in this example having the same size and shape and are therefore complementary. In the example of Figure 2a the opening 21a of the first part and the opening 22a of the second part are both adjacent to the third and fourth rollers. There is preferably a maximum distance between the opening of the first part and the bottom of each of the third and fourth rollers of 50mm. There is preferably a maximum distance between the opening of the second part and the sample plane of 50mm.

[0065] In Figure 2a the second part 22 is in a first position, namely forming an enclosure with the first part 21. Figure 2b depicts a second position for the second part in which it is away from the work area and the work area can therefore be accessed. The second part preferably moves a minimum of 150mm between the first and second positions. In the second position the second part is preferably a minimum of 20cm from the work area. In the example of Figure 2b the second part has been moved vertically.

[0066] The first opening is complementary to the second opening and arranged directly opposite (in a direction perpendicular to the sample plane). Consequently, the enclosure, while allowing the sample to pass through, constrains X-rays. As an example of the complementary shape and size of the first and second openings, they may have a coefficient of congruence of 0.95 in planes parallel to the sample plane. Put another way, the area of the first and second parts facing the sample plane are substantially congruent. The first and second openings preferably have a coefficient of congruence of 0.98 or more.

[0067] Figure 3a depicts a plan view of an example of the invention and the arrangement is similar to that depicted in Figure 2a. However, 3b depicts the second part in a second position after a horizontal translation. Again, the work area is exposed for easy access.

[0068] Figure 4 depicts an alternative example in which the opening of the first part 21 and the opening of the second part 22 are not adjacent to the third and fourth rollers but rather are directly opposite each other. In this example the third 4 and fourth 5 rollers are outside the enclosure formed by the first and second parts. However, Figure 5 depicts an alternative arrangement in which the third and fourth rollers (4 and 5, respectively) are inside the enclosure.

[0069] Figures 6a and 6b depict an example in which both the second 22 and first 21 parts are moveable. In the depicted example both the first and second parts are moved vertically. However, either or both of the first and second parts could equally be moved horizontally.

[0070] Figures 2 to 6 depict first and second parts with rectangular cross sections. However, the first and second parts need not have rectangular cross sections and Figure 7 depicts a second part 22 which more closely conforms to the path of the thin film.

[0071] Figure 8 depicts an alternative example in which the second part is formed of two sub-parts: a first sub-part 23 and a second sub-part 24. In this example the X-ray source 1 forms part of the enclosure (although it will be appreciated by those skilled in the art that it need not form part of the enclosure). Figure 8a depicts a first position of the second part, with the X-ray source 1, the first part 21, the first sub-part 23 and the second sub-part 24 forming the enclosure. Figure 8b depicts the second part in a second position, with first subpart 23 and second sub-part 24 shown moved away from the work area. Figure 8c depicts a further arrangement in which the X-ray source is also moved away from the work area.

[0072] Figures 9 and 10 depict alternative examples in which the openings of the first and second parts are slightly different sizes. In particular, in Figure 9 the opening 21a of the first part is slightly smaller than the opening 22a of the second part. In the first position the opening of the first part is within the second part. However, the degree of congruence is greater than 0.95 which helps to contain the X-rays. In Figure 10, the opening of the second part is smaller than the opening of the first part. In the first position the opening of the second part is within the first part.

[0073] Figure 11 depicts an example with a grating 80 arranged within the first part 21. The metal grating scatters radiation to prevent it from being reflected directly back to the detector and therefore compromising the collected data.

[0074] Figures 2-11 depict analysis apparatus used to detect diffracted X-rays i.e. with the detector on the same side of the thin film as the X-ray source. The X-rays are reflected from the thin film and then detected by the detector. Figures 2-11 could also be used to detect fluorescent (emitted) X-rays. Figure 12 depicts an analysis apparatus used in X-ray fluorescence (but not diffraction) i.e. in a transmissive mode. Here, the detector 120 is on the opposite side of the sample plane to the X-ray source 1 and X-rays which are transmitted through the thin film are detected. As will be appreciated, this arrangement of the X-ray source 1 and detector 120 could be incorporated into any of the arrangements of Figures 2- 11 and 13-18. Figure 13a depicts an X-ray apparatus used for non-flexible samples, for example plate glass or paintings. The apparatus has a first part 21 and a second part 22 forming an enclosure. These are arranged either side of a sample plane, along which a sample may be moved. The sample plane is formed by a plurality of rollers 131, 132, some of which may be driven rollers and some passive rollers.

[0075] The first part 21 and the second part 22 each extend the full length of the rollers 131, 132 and each have a first end 133, 135 and a second end 134, 136 arranged perpendicularly to the rollers. Within the second part 22 is an X-ray source which projects X- rays towards the sample and a detector is arranged either within the first part or within the second part.

[0076] The first and second part comprise metal, preferably steel which restricts the X-rays. There may be one or more windows 138 formed of leaded glass. The first part has a first opening 21a and the second part has a second opening 22a which are congruent shapes in planes parallel to the sample plane, i.e. along planes parallel to the sample plane they are the same shape and size. As can be seen in Figure 13a, the second part may comprise additional shoulders at either end, but the shape in planes parallel to the sample plane are the same. Furthermore, the first and second openings are arranged directly opposite each other. The first part and the second part together form the enclosure and therefore restrict X-rays from being transmitted outside the enclosure.

[0077] The second part 22 is movable between a first position, depicted in Figure 13a and a second position depicted in Figure 13b. In the first position the second opening is a maximum of 50mm from the sample plane which acts to restrict and confine the X-rays. Similarly, the first opening is a maximum of 150mm, and preferably a maximum of 50mm from the sample plane.

[0078] Figure 13a depicts a second position, in which the second part has been moved in a direction perpendicular to the sample plane. This allows easy access to the work area when the X-ray source is not in operation. In the second position the second opening is a minimum of 200mm from the sample plane.

[0079] Although the Figure 13 is depicted as having congruent first and second openings there may be some variation. For example, they should have a coefficient of congruence of at least 0.95 and preferably 0.98. The more congruent the shapes the more the X-rays will be restricted.

[0080] The arrangement described in conjunction with Figure 13 allows access to the work area, but also restricts the X-rays to a safe limit, preferably less than 1mSv at a distance of 1m, and preferably less than 0.1 mSv at a distance of 1m and preferably less than 0.01 mSv at a distance of 1m. Figure 14 depicts an enclosure having a first part 141 and a second part 142. The first part has side walls 51 , 52 and a base 83. The first part has a first opening and the second part has a second opening. A sample plane is defined by a plurality of rollers 85. Figure 14 depicts an example in which the first part is movable between a first position (depicted in Figure 14a) and a second position (depicted in Figure 14b). In the first position, the first part is close to the sample plane and there is a maximum distance between the opening and the sample plane of 150mm. The first part is configured to move perpendicularly to the sample plane and can be moved to a second position depicted in Figure 14b. The first part moves a minimum of 150mm between the first and second positions.

[0081] The first side wall has a first end proximal the sample plane and a second end distal the sample plane. Figure 15 depicts an example in which the base is movable between a first position, depicted in Figure 15a, in which the base extends between the first and second side walls and a second position, depicted in Figure 15b. The base is rotatable around a pivot 81 at the second end of the first side wall. When the sample is being irradiated the base is in the first position but can be rotatable to a second position when there is no radiation. When in the first position there is a seal between the base 83 and the second wall 52.

[0082] The ability to open the enclosure is particularly useful for applications where debris may accrue in the enclosure as the enclosure can be opened to remove the debris.

[0083] Figure 16 depicts an alternative enclosure to that depicted in Figure 15. Similar to the arrangement of Figure 15, the base 93 is movable between a first position (depicted in Figure 16a) and a second position (depicted in Figure 16b). However, both the base 93 and the first side wall 51 rotate, as a single unit, around a pivot 91 at the first end of the first side wall.

[0084] Although Figures 15 and 16 depict either none of the first side wall being rotated (Figure 15) or all of the first side wall being rotated (Figure 16), as an alternative just a portion of the first side wall could be rotated together with the base.

[0085] Figure 17 depicts an arrangement in which a portion of the first side wall 51 , a portion of the second side wall 52 and the base 103 all rotate together. They all rotate around the combined centre of mass 101 of the portion of the first side wall, the portion of the second side wall and base. Rotating around the centre of mass 101 means that it is easy to rotate between the first position and the second position.

[0086] Although Figure 17 depicts rotation of a portion of the first side wall and a portion of the second side wall together with the base a different portion of the first and second side walls could be rotated: for example, more or less of the side walls could be rotated. Figure 17 also depicts a grating 125 which can be used to scatter X-rays so that fewer are reflected back to the detector. Whilst the grating 125 is shown integral with base 103, the grating may be positioned at a different located within the first and second walls. In each of the examples of Figures 15, 16 and 17, the base is substantially parallel to the inspection plane in the first position. This enables debris to be collected. In the second position, the base is not parallel to the inspection plane such that base can be cleaned and / or emptied.

[0087] Figures 2-13 depict the second part being moved whereas figures 14-17 depict the first part being moved. However, both the first and the second part may both be movable.

[0088] Figure 18a depicts a side view of a system with a first X-ray analysis apparatus 100 and a second X-ray analysis apparatus 200 arranged adjacent to each other. Each of the X- ray analysis apparatuses has an X-ray source 1, 201, a first part 21 , 221 and a second part 22, 222. The rollers 5 and 205 are parallel to each other and their lengths overlap for at least a portion, and preferably all, thereof. As can be seen, the thin film 10 is passed directly from the first apparatus 100 to the second apparatus 200. The thin film passes perpendicularly to the length of the rollers 5, 205 between the two apparatuses. Although the two apparatuses are depicted at the same vertical height it will be appreciated that they could equally be at different heights. Although the first apparatus 100 and the second apparatus 200 are depicted as identical they could be different arrangements. As an example, the first apparatus could be a diffraction apparatus with the detector on the same side as the X-ray source whereas the second apparatus could be a transmissive apparatus with the detector on the opposite side of the thin film to the X-ray source.

[0089] Figure 18b depicts a plan view of portions of the system depicted in Figure 18a. The thin film 10 passes between the first apparatus 100 and the second apparatus 200. The X- ray source (and detector) 1 of the first apparatus is at a first position along the length of the apparatus, or rollers, whereas the X-ray source (and detector) 201 of the second apparatus is at a second, different, position along the length of the apparatus, or rollers. This allows different portions along the width of the thin film to be examined. The two detectors 1 , 201 may perform the same measurement on different portions of the film or alternatively could perform different measurements. Advantageously, by using multiple apparatus in a system, the X-ray source / detector in each apparatus can be moved without any vibrations affecting the X-ray source / detector in the other apparatus. Thus, the sources and detectors in the respective apparatuses are more independent from each other.

[0090] Although Figure 18 depicts two apparatus adjacent to each other there could be more apparatus, with a single thin film being passed between all the apparatus.

[0091] As will be appreciated, features from different examples can be combined so, for example, the grating depicted in Figure 11 can be combined with other depicted examples and the movement(s) described in conjunction with various examples can be combined with other examples. “and / or” where used herein is to be taken as specific disclosure of each of the two specified features or components with or without the other. For example “A and / or B” is to be taken as specific disclosure of each of (i) A, (ii) B and (iii) A and B, just as if each is set out individually herein. Unless context dictates otherwise, the descriptions and definitions of the features set out above are not limited to any particular aspect or example of the invention and apply equally to all aspects and examples which are described.

[0092] It will further be appreciated by those skilled in the art that although the invention has been described by way of example with reference to several examples, it is not limited to the disclosed examples and that alternative examples could be constructed without departing from the scope of the invention as defined in the appended claims.

Claims

CLAIMS1 . An X-ray analysis apparatus comprising: a first roller having a length; a second roller, the first roller and the second roller forming a sample plane along which a sample passes; an X-ray source for irradiating the sample with X-rays and configured, in operation, to project X-rays to a work area between the first and second rollers; a detector configured to detect X-rays; an enclosure extending at least the length of the first roller and comprising a first part and a second part, wherein the first part is arranged on a first side of the sample plane, opposite to the X- ray source, and has a first opening adjacent the sample plane and a base distal the sample plane, wherein the second part is arranged on a second side of the sample plane, the same side as the X-ray source, and has a second opening, wherein the first opening and the second opening are complementary, and wherein at least one of the second part and at least the base of the first part is movable between a first position, wherein the enclosure encloses the X-ray source and the detector, and a second position.

2. The X-ray analysis apparatus according to claim 1 wherein the first opening and the second opening have a coefficient of congruence, in planes parallel to the sample plane, of 0.95 or more.

3. The X-ray analysis apparatus according to claim 2 wherein the first and second openings have congruent shapes in planes parallel to the sample plane.

4. The X-ray analysis apparatus according to any one of the preceding claims wherein the second part is movable perpendicularly to the sample plane between the first position and the second position.

5. The X-ray analysis apparatus according to claim 4 wherein the second part is configured to move a minimum of 150mm between the first and second positions.

6. The X-ray analysis apparatus according to any one of the preceding claims wherein the entire first part is movable perpendicularly to the sample plane between the first position and the second position.

7. The X-ray analysis apparatus according to claim 6 wherein the first part moves a minimum of 150mm between the first and second positions.

8. The X-ray analysis apparatus according to any one of the preceding claims wherein the first part comprises a first side wall and a second side wall, the first side wall having a first end proximal the sample plane, corresponding to the first opening, and a second end distal the sample plane, coupled to the base.

9. The X-ray analysis apparatus according to claim 8 wherein the base is configured to rotate, between the first position and the second position, around a pivot on the first side wall.

10. The X-ray analysis apparatus according to claim 9 wherein the pivot is adjacent the second end of the first side wall.

11. The X-ray analysis apparatus according to claim 9 wherein the pivot is adjacent the first end of the first side wall, and the base is configured to rotate, together with the first side wall, around said pivot.

12. The X-ray analysis apparatus according to claim 9 wherein the base and at least a portion of the first side wall and at least a portion of the second side wall are configured to rotate together as a unit.

13. The X-ray analysis apparatus according to claim 12 wherein the base, the portion of the first side wall and the portion of the second side wall are configured to rotate around the combined centre of mass of the base, the portion of the first side wall and the portion of the second side wall.

14. The X-ray analysis apparatus according to any one of the preceding claims wherein, in the first position the first opening is a maximum distance of 150mm from the sample plane and the second opening is a maximum distance of 50mm from the sample plane.

15. The X-ray analysis apparatus according to any one of the preceding claims wherein, each of the first and second parts, at the ends of each of their respective lengths, comprises an end portion perpendicular to the length of the roller.

16. The X-ray analysis apparatus according to any one of the preceding claims wherein the first and / or second parts comprise metal.

17. The X-ray analysis apparatus according to claim 16 wherein the first and / or second parts comprise steel.

18. The X-ray analysis apparatus according to any one of the preceding claims wherein the first and / or second parts comprise leaded glass.

19. The X-ray analysis apparatus according to any one of the preceding claims wherein, in the first position, the first opening and the second opening are directly opposite each other in a direction perpendicular to the sample plane.

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