CIRCULAR X-RAY TUBE AND AN X-RAY INSTRUMENT COMPRISING THE CIRCULAR X-RAY TUBE

Abstract

The circular X-ray tube for the irradiation of the object (1) by X-radiation comprising the circular body (2) and at least two friction elements that rub together whereby forming a triboluminescent source of X-radiation. The one friction element comprises at least one circumferential element (3) arranged on the external circumferential side of the circular body (2) of the X-ray tube and the other friction element comprises at least one pressure element (4) that is pressed against the circumferential element (3), where the pressure element (4) is adapted for dragging upon the circumferential element (3), and/or at least one circumferential element (3) is adapted for pulling through under the pressure element (4). The X-ray instrument utilizes the circular X-ray tube and the imaging detectors (7) of ionizing radiation.

Claims

1. The circular X-ray tube for the irradiation of the object (1) by X-radiation generated during the triboluminescence effect comprising the circular body (2) and at least two friction elements rubbing against one another that form the triboluminescent source of X-radiation characterized in that one of the friction elements comprises at least one circumferential element (3) arranged at the external circumferential side of the circular body (2) of the X-ray tube, and the other friction element comprises at least one pressure element (4) that is pressed against the circumferential element (3), where the pressure element (4) is adapted for dragging upon the circumferential element (3), and/or at least one circumferential element (3) is adapted for pulling through under the pressure element (4).

2. The circular X-ray tube according to claim 1 characterized in that the circular body (2) is fitted with at least one shield (5) of ionizing radiation, where the shield (5) is equipped with at least one opening for the unshielded passage of X-radiation.

3. The circular X-ray tube according to claim 2 characterized in that the position of the opening in the shield (5) with regard to the circular body (2) and/or the size of the opening in the shield (5) is adjustable in a controlled manner.

4. The circular X-ray tube according to claim 2 characterized in that the shield (5) is movable with regard to the circular body (2).

5. The circular X-ray tube according to claim 1 characterized in that the circumferential element (3) comprises at least one friction belt whose free ends are fixed to wind-up spools (6).

6. The circular X-ray tube according to claim 1 characterized in that the circular body (2) is openable or dismountable into at least two parts.

7. The X-ray instrument for the acquisition of X-ray images of the object (1) comprising the circular X-ray tube according to claim 1 for the irradiation of the object (1) by X-radiation arranged in the region for the positioning of the object (1) that is found inside the space delimited by the circular body (2) of the circular X-ray tube, or under the space or above the space delimited by the circular body (2), and at least one detector (7) of ionizing radiation characterized in that the detector (7) of ionizing radiation is planar with an impact detection surface and is arranged inside the space delimited by the circular body (2) of the circular X-ray tube and/or under the space or above the space delimited by the circular body (2), where the detector (7) is aligned behind the region for the positioning of the irradiated object (1) with its impact detection surface facing the region for the positioning of the irradiated object (1).

8. The X-ray instrument according to claim 7 characterized in that at least three detectors (7) are arranged to form a polygonal detection field copying the ground plan of the circular body (2).

9. The X-ray instrument according to claim 7 characterized in that at least one detector (7) is fitted with a grid electrode (8) for shielding the X-radiation striking upon indirectly.

10. The X-ray instrument according to claim 7 characterized in that at least one detector (7) is tilting for the angular adjustment of its impact detection surface.

11. The X-ray instrument according to claim 7 characterized in that it is equipped with a shield (9) to shield at least one impact detection surface of the detector (7) from the direct impact of the X-radiation from the triboluminescent source.

12. The X-ray instrument according to claim 7 characterized in that it is fitted with at least one means for the rotational movement of the X-ray tube and the detector (7) around the object (1), where the detector (7) is fixed with regard to the circular X-ray tube, or with at least one means for the rotational movement of the object (1) in the region for the positioning of the irradiated object (1).

13. The X-ray instrument according to claim 7 characterized in that it is fitted with at least one means for the rotational movement of the X-ray tube around the object (1), where the detectors (7) are arranged in a circle and are fixed, and where the circular X-ray tube is rotary with regard to the object (1) and the detectors (7).

Description

EXPLANATION OF DRAWINGS

[0030] The present invention will be explained in detail by means of the following figures where:

[0031] FIG. 1 shows a schematic diagram of the use of the invention for X-ray laminography,

[0032] FIG. 2a shows a plan view of the schematic diagram of the invention with only one pressure element,

[0033] FIG. 2b shows a side view of the schematic diagram of the invention with only one pressure element,

[0034] FIG. 3a shows a plan view of the schematic diagram of the invention with three pressure elements and with a rotating shield,

[0035] FIG. 3b shows a side view of the schematic diagram of the invention with three pressure elements and with a rotating shield,

[0036] FIG. 4 shows a schematic diagram of the invention with unequally distant pressure elements,

[0037] FIG. 5a shows a plan view of the schematic diagram of the invention with rotating pressure elements and a rotating shield,

[0038] FIG. 5b shows a side view of the schematic diagram of the invention with rotating pressure elements and with a rotating shield,

[0039] FIG. 6 shows a side view of the schematic diagram of the invention with rotating pressure elements and with a static shield,

[0040] FIG. 7 shows a schematic diagram of the invention with detectors fitted with a grid electrode to shield X-ray beams with an undesirable angle of incidence,

[0041] FIG. 8a shows a plan view of the schematic diagram of the invention with wide shield collimation openings and with detectors fitted with a grid electrode to shield X-ray beams with an undesirable angle of incidence,

[0042] FIG. 8b shows a side view of the schematic diagram of the invention with wide shield collimation openings and with detectors fitted with a grid electrode to shield X-ray beams with an undesirable angle of incidence,

[0043] FIG. 9 shows a schematic diagram of the invention with a circumferential element comprising a friction belt wound on wind-up spools and pulled-through under pressure elements,

[0044] FIG. 10a shows a plan view of the schematic diagram of the invention with a circumferential element comprising a friction belt wound on wind-up spools and with movable pressure elements,

[0045] FIG. 10b shows a side view of the schematic diagram of the invention with a circumferential element comprising a friction belt wound on wind-up spools and with movable pressure elements,

[0046] FIG. 11 shows a schematic diagram of the use of the invention fitted with a secondary shield,

[0047] FIG. 12 shows a schematic diagram of the invention with a divided circular X-ray tube,

[0048] FIG. 13 shows a schematic diagram of the invention with two pressure elements.

AN EXAMPLE OF THE INVENTION EMBODIMENT

[0049] It shall be understood that the specific cases of the invention embodiments described and depicted below are provided for illustration only and do not limit the invention to the examples provided here. Persons skilled in the art will find or, based on routine experiments, will be able to provide a greater or lesser number of equivalents to the specific embodiments of the invention which are described here. Also such equivalents will be included in the scope of the following patent claims.

EXAMPLE 1

[0050] FIG. 1 shows a schematic diagram of an example of the application of the X-ray instrument with the circular X-ray tube that can be used for X-ray laminography. The planar irradiated object 1, for example a composite plate, is positioned under the circular X-ray tube, of which only the circular body 2 is visible in the schematic diagram. The circular X-ray tube emits an X-ray beam striking upon the irradiated object 1. Under the object 1, an imaging detector 7 of ionizing radiation, whose impact detection surface is struck upon by the X-ray beam penetrating the object 1, is provided. The imaging detector 7 can be, for example, the model known under the TimePix brand.

[0051] The X-ray beam is gradually radiated within the full range of 360, allowed by the circular X-ray tube, which results in the X-radiation passage through the exposed part of the irradiated object 1. The result of X-ray laminography is evaluated from a set of acquired images in a way known to a person skilled in the art that does not need to be described in detail to illustrate the example of the invention embodiment.

EXAMPLE 2

[0052] FIG. 2a and FIG. 2b provide a schematic diagram of an example of the embodiment of the X-ray instrument with the circular X-ray tube with an unshielded X-ray beam. For better clarity of the figures, the circular body 2 is not provided. The circumferential element 3, comprised by e.g. a piece of plastic material, is supported by the circular body 2, or, where applicable, is integrated in the circular body 2. One pressure element 4 manufactured from e.g. tungsten is dragged upon the circumferential element 3. Eleven detectors 7 form a polygonal circular detection field without gaps that allows, with the rotating pressure element 4, eleven direct X-ray images per one revolution of the circular body 2 to be acquired. The detection field is arranged under the space delimited by the circular body 2, as shown in FIG. 2b. The detectors 7 can be tilted with regard to the X-ray beam to improve the X-radiation incidence onto their impact detection surface.

[0053] In a modified Example 2, not provided in the figure, a plurality of pressure elements 4 can be dragged upon the circumferential element 3 at the same time, which results in n*11 of images per revolution of the pressure elements 4, where n is a substituent of the actual number of the pressure elements 4. The number of the pressure elements 4 cannot be increased unlimitedly as with a larger number of triboluminescent sources emitting at the same time, X-ray images become distorted.

EXAMPLE 3

[0054] FIG. 3a and FIG. 3b provide a schematic diagram of an example of the embodiment of the X-ray instrument with the circular X-ray tube with an X-ray beam collimated by a shield 5. For better clarity of the figures, the circular body 2 is not provided but only the shield 5 is provided in the figure. The shield 5 is comprised of for example lead. The schematic diagram shows three openings in the shield 5 that collimate X-ray beams from three neighbouring pressure elements 4. The pressure elements 4 have regular distances from one another. The detectors 7 are employed similarly as in Example 2.

[0055] The shield 5 rotates together with the rotating pressure elements 4, so that the openings in the shield 5 correspond with the pressure elements 4. The collimation of X-ray beams eliminates X-ray image distortion.

EXAMPLE 4

[0056] FIG. 4 shows a schematic diagram of an embodiment of the X-ray instrument where, unlike in Example 3, a plurality of collimators (openings in the shield 5), that do not rotate together with the pressure elements 4, are employed. The pressure elements 4 and/or collimators do not have to be at regular mutual distances. Due to the different mutual distance each pressure element 4 has a different irradiation angle with regard to the irradiated object 1. The detectors 7 can be arranged in the detection field in an irregular way with gaps between individual detectors 7. The mutual position of the openings in the shield 5 and the detectors 7 is selected in a manner minimizing the interference of acquired images by the neighbouring sources of X-radiation.

[0057] In the X-ray instrument provided in FIG. 4 the entire system can rotate within a limited range of angles to acquire tomographic projections from a plurality of angles.

EXAMPLE 5

[0058] FIG. 5a and FIG. 5b provide an embodiment of the X-ray instrument whose circular X-ray tube is fitted with the pressure elements 4 and the rotary shield 5 for the simultaneous rotational movement of the openings in the shield 5 and the pressure elements 4. The detection field comprises eleven detectors 7 with minimal gaps in between. FIG. 5a shows the beams of X-radiation penetrating the detectors 7 that are arranged in the space delimited by the circular body 2. The detectors 7 are silicon-based and therefore their effect on the passing the beams of X-radiation is minimal.

[0059] If the irradiation should not include X-radiation passing through the detectors 7, it is possible to arrange the detection field of the X-ray instrument under the space delimited by the circular body 2 of the circular X-ray tube as shown in FIG. 5b.

EXAMPLE 6

[0060] FIG. 6 shows a schematic diagram of an embodiment of the X-ray instrument whose circular X-ray tube has a high number of pressure elements 4 arranged along the circumferential element 3. The pressure elements 4 rotate around the circumferential element 3. The circular X-ray tube is fitted with the shield 5 with eleven collimation openings that are static. The circular X-ray tube is used in the X-ray instrument fitted with eleven detectors 7 arranged into a detection field.

[0061] The pressure elements 4 start rotating and whenever the pressure element 4 passes the opening of the shield 5 a flash of X-radiation from the beam is generated. It is possible to acquire eleven images at the same time per unit of time. A person skilled in the art can easily adjust the number of collimation openings in the circular X-ray tube and the number of the detectors 7 in the detection field of the X-ray instrument. A higher number of pressure elements 4 and the speed of their rotational movement affect the number of images per unit of time.

[0062] To increase the number of irradiation angles, the object 1 must rotate, or the circular X-ray tube with the detectors 7 must rotate in the X-ray instrument around the object 1.

EXAMPLE 7

[0063] FIG. 7 shows a schematic embodiment of the X-ray instrument whose circular X-ray tube is, unlike in Example 6, fitted with wider collimation openings in the shield 5. The X-ray instrument utilizing this circular X-ray tube is fitted with the detectors 7, whose impact detection surfaces are equipped with grid electrodes 8 to shield the beams of X-radiation striking upon the impact detection surface of the detectors 7 at an undesirable angle. The detection field comprises gaps between the detectors 7 adjacent to the collimation openings in the shield 5 allowing the beam of X-radiation to freely pass through to the irradiated object 1. The detection field is arranged in the space delimited by the circular body 2.

[0064] To increase the number of irradiation angles, the object 1 must rotate, or the circular X-ray tube with the detectors 7 must rotate in the X-ray instrument around the object 1.

EXAMPLE 8

[0065] FIG. 8a and FIG. 8b shows a schematic diagram of an embodiment of the X-ray instrument derived from the X-ray instrument provided in Example 7. The main difference of this embodiment of the invention rests in the fact that the field is arranged under the space delimited by the circular body 2. Due to the fact that the detectors 7 do not shield the beams of X-radiation coming from the shield 5 openings, no gaps are provided between the detectors 7.

EXAMPLE 9

[0066] FIG. 9 shows a schematic diagram of an embodiment of the X-ray instrument whose circular X-ray tube has a circumferential element 3 comprising a friction belt rewound by two wind-up spools 6. The wind-up spools 6 may be equipped, for example inside their drums, with a drive on the basis of electric motor. Tensioning pins 10 to tension the friction belt 3 prior to winding onto the wind-up spools 6 are arranged at the circumferential element 3. The friction belt is made of flexible plastic material and its contact surface, against which the pressure elements 4 are pressed, is fitted with microparticles increasing its sliding friction coefficient.

[0067] The illustrated embodiment of the invention shows a friction belt shared by all pressure elements 4. However, it is possible to equip the circular X-ray tube for each pressure element 4 with a separate friction belt with own wind-up spools 6.

[0068] The detection field of the X-ray instrument has gaps between individual detectors 7 to ensure the undisturbed passage of the beams of X-radiation.

[0069] To change irradiation angles when acquiring X-ray images it is possible to rotate the irradiated object 1 or turn the X-ray instrument around the object through an angle within a limited range of angles.

EXAMPLE 10

[0070] FIG. 10a and FIG. 10b show a schematic diagram of an embodiment of the X-ray instrument whose circular X-ray tube has a circumferential element 3 comprising a friction belt rewound by two wind-up spools 6. The difference from Example 9 is the position of the detector 7 outside the plane with the X-radiation sources 2, see FIG. 10b. This will enable a limited rotational movement of the X-radiation source to acquire a larger scope of projection angles. The friction belt comprising the circumferential element 3, pressure elements 4 and collimation openings in the shield 5 turns through an angle with regard to the detectors 7. To change irradiation angles when acquiring X-ray images it is also possible to rotate the irradiated object 1.

EXAMPLE 11

[0071] FIG. 11 shows a schematic diagram of an embodiment of the X-ray instrument that is fitted with a secondary shield 9 to shield the direct beams of X-radiation. The secondary shield 9 is equipped with collimation openings allowing the passage of scattered X-radiation and fluorescent X-radiation towards the detectors 7. In addition, the secondary shield 9 is fitted with openings for the passage of a direct beam of X-radiation penetrating the irradiated object 1 towards the detector 7. Due to this arrangement it is possible to measure in both the transmission mode (standard CT) and in the mode that creates images using scattered and/or fluorescent radiation and the technique of camera obscura. Information from all three modes of imaging can be combined.

[0072] The secondary shield 9 is stationary with regard to the X-ray tube and the entire instrument rotates with regard to the object 1 or the object 1 rotates with regard to the X-ray instrument.

EXAMPLE 12

[0073] FIG. 12 shows a schematic embodiment of the X-ray instrument whose circular X-ray tube is divisible into two halves according to division boundaries 11. Each half of the circular X-ray tube is fitted with its own circumferential element 3 in the form of the friction belt wound onto the wind-up spools 6.

EXAMPLE 13

[0074] FIG. 13 shows a schematic diagram of an embodiment of the X-ray instrument whose circular X-ray tube is fitted with two circumferential elements 3 in the form of two friction belts. Each circumferential element 3 has its own wind-up spools 6.

[0075] The pressure elements 4 form a point of tension situated at the collimation opening of the shield 5, where the pulled-through bottom circumferential element 3 rubs against the upper circumferential element 3 that forms a barrier protecting the pressure element 4 against wearing.

[0076] It applies to all the aforementioned examples that the means for rotational movement of the object 1 can be an adjustable table, or where applicable, a handling arm representing a technically feasible problem for a person skilled in the art. A means for the implementation of movements in the X-ray instrument is for example an electric motor whose rotational action is transferred by gears or belts to the movable parts of the X-ray instrument.

[0077] It is obvious that a person skilled in the art may combine other embodiments of the invention from the selected parameters of the aforementioned examples.

INDUSTRIAL APPLICABILITY

[0078] The circular X-ray tube and the X-ray instrument with the circular X-ray tube according to the invention will find application in the field of research and development, in industry, in particular for quality control, and also in the public health sector.

OVERVIEW OF THE POSITIONS

[0079] 1 object

[0080] 2 circular body

[0081] 3 circumferential element

[0082] 4 pressure element

[0083] 5 shield

[0084] 6 wind-up spools

[0085] 7 ionizing radiation detector

[0086] 8 detector grid electrode

[0087] 9 secondary shield

[0088] 10 tensioning pin

[0089] 11 division boundary