The present application is directed to an x-ray device and a method of applying x-ray radiation.
X-ray radiation is being used in a multitude of applications, ranging from medical imaging or therapy or security checks at airports to crystallography. The most common devices for generating x-ray radiation are x-ray tubes, which are vacuum tubes in which electrons are emitted by a cathode and accelerated towards an anode, where the electrons produce x-ray radiations through bremsstrahlung or other physical processes. X-ray tubes are generally simpler in construction and use than other ways of producing x-ray radiation like for example synchrotron radiation generated in particle accelerators.
U.S. Patent Application Publication No. 2018/0333591 A1 describes such an x-ray device, which further includes a converter to transform polychromatic x-ray radiation produced by bremsstrahlung into characteristic monochromatic radiation, which is desirable in particular in medical applications as results may be obtain with lower radiation dosages. In said x-ray device and other similar x-ray devices, as described for example in German Patent DE 19 639 241 C2, the x-ray radiation has to be directed from the anode to the converter, which leads complex beamlines for the x-ray radiation traveling from the anode to the point of application.
This leads to generally small angles of incidence of the x-ray radiation and accompanying lowered intensity of radiation as well as heating of other components of the x-ray device by x-ray photons which are not directed towards the point of application.
Against this background, an objective of the present disclosure is to simplify the beamlines of x-ray radiation in an x-ray device.
According to the present disclosure, this task is solved by an x-ray device and by a method of applying x-ray radiation.
The scope of the present disclosure is defined solely by the appended claims and is not affected to any degree by the statements within this summary. The present embodiments may obviate one or more of the drawbacks or limitations in the related art.
Consequently, an x-ray device is provided, which includes a housing configured to provide (or including) a vacuum therein, a cathode arranged inside the housing and configured to emit electrons, an anode arranged inside the housing and configured to produce x-ray radiation when impacted by electrons emitted by the cathode, and a converter configured to convert the x-ray radiation produced by the anode into monochromatic x-ray radiation. The anode is configured to produce x-ray radiation in transmission and is arranged between the cathode and the converter.
Furthermore, a method of applying x-ray radiation is provided. In this method electrons are emitted from a cathode. X-ray radiation is produced with an anode being impacted by the electrons emitted from the cathode, x-ray radiation produced by the anode is converted into monochromatic x-ray radiation with a converter, and the monochromatic x-ray radiation is applied. The anode is configured to produce x-ray radiation in transmission and is arranged between the cathode and the converter.
It is an idea of the present disclosure to combine an anode configured to produce x-ray radiation in transmission with converter for converting said x-ray radiation into monochromatic x-ray radiation. This greatly simplifies the beam path the x-ray radiation travels on from the anode to the region of application via the converter, compared to previously known x-ray devices. This simplified design further allows an improved provision of supplementary functions to the x-ray device, in particular an arrangement of ways for cooling the anode and/or the converter.
Advantageous configurations and further embodiments may be derived from the dependent claims as well as from the description with reference to the figures.
According to a further embodiment, the x-ray device includes a transmission body, wherein the transmission body includes a material transparent to x-ray radiation. Such a transmission body may be arranged as a way of dissipating heat away from the anode and/or the converter, advantageously prolonging the lifetime of the respective parts.
According to a further embodiment, the transmission body is arranged in contact with the anode. In that configuration, the transmission body may advantageously dissipate heat from the anode by heat conduction.
According to a further embodiment, the transmission body is arranged structurally separated from the converter. In that configuration, the converter may be easily exchangeable allowing improved advantageous adaptability of the x-ray device.
According to a further embodiment, the transmission body is arranged in contact with the converter. In that configuration, the transmission body may advantageously dissipate heat from the converter by heat conduction.
According to a further embodiment, the converter is arranged between the anode and the transmission body in contact with the anode and the transmission body. In that configuration, the transmission body may be formed especially large, advantageously improving its capacity to dissipate heat from both the anode and the converter by heat conduction.
According to a further embodiment, the x-ray device includes a cooling device configured to cool the converter. This allows even better dissipation of heat away from the converter, advantageously improving the lifetime of the converter.
According to a further embodiment, the converter is arranged inside the transmission body. In that configuration, the converter may be arranged especially close to the anode, advantageously increasing the amount of x-ray radiation produced by the anode converted into monochromatic x-ray radiation by the converter.
According to a further embodiment, the converter is arranged in a curved form such that at least one lateral edge of the converter is in contact with the anode. This advantageously increases the amount of x-ray radiation produced by the anode converted into monochromatic x-ray radiation by the converter even further.
According to a further embodiment, the x-ray device includes a cooling device configured to cool the transmission body. This allows even better dissipation of heat away from the transmission body, advantageously improving its capability of dissipating heat away from the anode and/or the converter.
According to further embodiment, the x-ray device includes a cooling device configured to cool the anode. This allows even better dissipation of heat away from the anode, advantageously improving the lifetime of the anode.
According to further embodiment, the anode, the converter and/or the transmission body are configured to be rotatable around an axis of rotation. Such a configuration enables a limitation of which parts of the respective components are heated during use of the x-ray device, which allows for an advantageously continuous dissipation of heat even when producing high intensities of x-ray radiation.
The above-mentioned configurations and further embodiments may be combined with each other, if it is reasonable. Further possible configurations, further embodiments and implementations of the disclosure also include combinations of features of the disclosure described before or in the following with regard to the examples of implementation not explicitly mentioned. In particular, the skilled person will also add individual aspects as improvements or additions to the respective fundamental form of the present disclosure.
This disclosure is explained in more detail below using the examples given in the schematic illustrations.
The following figures are intended to convey a further understanding of the forms in which the disclosure is carried out. They illustrate embodiments and serve in connection with the description to explain principles and concepts of the disclosure. Other embodiments and many of the above-mentioned advantages may be derived from the drawings. The elements of the drawings are not necessarily shown to scale.
In the figures of the drawings, identical elements, characteristics and components with the same function and effect are provided with the same reference signs, unless otherwise specified.
In use, the cathode 3 emits electrons into the vacuum inside the housing 2, for example, through the field emission effect, thermionic emission, or other well-known physical processes. Under effect of the electrical field between the cathode 3 and the anode 4, the electrons are accelerated towards the anode 4. Upon impacting on the anode 4, the electrons interact with the anode 4 and thereby produce x-ray radiation through bremsstrahlung, characteristic x-ray emission, or the like. The anode 4 is configured to produce x-ray radiation in transmission, which means that the produced x-ray radiation radiates onwards from the anode 4 in the direction of the converter 5. X-ray radiation impacting on the converter 5 is converted into monochromatic x-ray radiation, which in the embodiment shown in
As shown in
The x-ray device 1 functions essentially the same as the x-ray device 1 described in conjunction with
In use, the anode 4, the converter 5, the transmission body 6, and the heat conductor 7 rotate around the axis of rotation X. Therefore, only a part of the respective parts interacts with the electrons emitted by the cathode 3, which is not shown. As only the parts interacting with the electrons heat up, said heat may be continuously dissipated, which greatly increases the lifetime of the respective parts of the x-ray device.
In the embodiment shown in
The converter 5 is arranged separate from both the anode 4 and the transmission body 6. In this configuration, the converter 5 may be configured to be easily replaceable, which allows the x-ray device 1 to be configured to different intended purposes. For example, multiple converters may be arranged on a wheel and be exchanged by rotating said wheel.
The x-ray device 1 shown in
In the perspective shown in
Furthermore, the anode 4 shown in
The converter 5 shown in
The anodes shown in the preceding figures may include material suitable for producing x-ray radiation upon being impacted by high-energy electrons, for example electrons having an energy of 50 keV, such as tungsten, gold, or the like. In order to configure an anode to produce x-ray radiation in transmission, the anode may include a thin layer of such a material, including, for example, a thickness between 5 μm (micrometers) and 25 μm (micrometers). Other thicknesses are also possible.
The converters shown in the preceding figures may include materials suitable for converting x-ray radiation, for example x-ray radiation produced by bremsstrahlung, into monochromatic x-ray radiation, like silver, gallium-oxide, or the like. The converter may include thin layers of such materials, in particular in the embodiments where the converter is embedded in the transmission body. Such layers may be as thin as for example 5 μm (micrometers) or 10 μm (micrometers) and may be as thick as for example 25 μm (micrometers) or 100 μm (micrometers). Other thicknesses are also possible.
The transmission bodies shown in the preceding figures may include materials which are transparent to x-ray radiation, in particular to x-ray radiation above the absorption edge of the converter, and also possess high heat capacitance and heat conduction. Examples for such materials include copper, carbon, silicon-carbide, and the like.
Even though not shown in the preceding figures, any embodiment may further include a cooling device for the anode, the converter and/or the transmission body. One cooling device may be provided for all of these or for a plurality thereof, or one cooling device may be provided for each of these. Such cooling devices may include water cooling or air-convection cooling.
Although the disclosure was illustrated and described in more detail by the exemplary embodiments, the disclosure is not restricted by the disclosed examples and other variations may be derived herefrom by the person skilled in the art without departing from the scope of protection of the disclosure. It is therefore intended that the foregoing description be regarded as illustrative rather than limiting, and that it be understood that all equivalents and/or combinations of embodiments are intended to be included in this description.
It is to be understood that the elements and features recited in the appended claims may be combined in different ways to produce new claims that likewise fall within the scope of the present disclosure. Thus, whereas the dependent claims appended below depend from only a single independent or dependent claim, it is to be understood that these dependent claims may, alternatively, be made to depend in the alternative from any preceding or following claim, whether independent or dependent, and that such new combinations are to be understood as forming a part of the present specification.
Number | Date | Country | Kind |
---|---|---|---|
19195781 | Sep 2019 | EP | regional |
The present patent document claims the benefit of U.S. Provisional Patent Application No. 62/777,043, filed Dec. 7, 2018, which is hereby incorporated by reference in its entirety. The present patent document also claims the benefit of European Patent Application No. 19195781.0, filed Sep. 6, 2019, which is also hereby incorporated by reference.
Number | Name | Date | Kind |
---|---|---|---|
3867637 | Braun | Feb 1975 | A |
3983397 | Albert | Sep 1976 | A |
4382181 | Wang | May 1983 | A |
6041095 | Yokhin | Mar 2000 | A |
6295338 | Kuzniar | Sep 2001 | B1 |
9326744 | Silver | May 2016 | B2 |
20080084966 | Aoki | Apr 2008 | A1 |
20180333591 | Silver | Nov 2018 | A1 |
20200182806 | Kappler | Jun 2020 | A1 |
Number | Date | Country |
---|---|---|
2242521 | Dec 1996 | CN |
206002466 | Mar 2017 | CN |
19639241 | Jul 1998 | DE |
2008084853 | Apr 2008 | JP |
2009054562 | Mar 2009 | JP |
Entry |
---|
European Search Report for European Application No. 19195781.0-1212 dated Apr. 23, 2020. |
Jacobson, Bertil, and Lars Nordberg. “X-Ray Tube with a Built-In Secondary Target for Exciting K Lines.” Review of Scientific Instruments 34.4 (1963): 383-385. |
Tan, Dagang. “A novel X-ray source for diagnosis: K-fluorescent enhanced X-ray tube.” Proceedings of the 22nd Annual International Conference of the IEEE Engineering in Medicine and Biology Society (Cat. No. 00CH37143). vol. 4. IEEE, 2000. pp. 2506-2509. |
Baldelli, P. et al., “Development of a quasi-monochromatic source for mammography applications,” Nuclear Inst. and Methods in Physics Research, A; vol. 518, issue 1-2 (Frontier Detectors for Frontier Physics: Proceeding); pp. 386-388; 2004. |
Number | Date | Country | |
---|---|---|---|
20200187339 A1 | Jun 2020 | US |
Number | Date | Country | |
---|---|---|---|
62777043 | Dec 2018 | US |